Merge pull request 'bugfix/15-docker-deployment' (#21) from bugfix/15-docker-deployment into main

Reviewed-on: #21

.gitea/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,24 @@
+---
+name: "Bug Report"
+about: Report an error or unexpected behavior in MiauInv
+title: "[BUG] "
+labels: ["Kind/Bug"]
+---
+
+### Description
+A clear and concise description of what the bug is.
+
+### Steps to Reproduce
+1. Go to '...'
+2. Click on '...'
+3. Scroll down to '...'
+4. See error
+
+### Expected Behavior
+A clear and concise description of what you expected to happen.
+
+### Logs and Error Messages
+If applicable, add server logs or browser console outputs here:
+```text
+Insert logs here
+```

.gitea/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,18 @@
+---
+name: "Feature Request"
+about: Suggest an idea or enhancement for MiauInv
+title: "[FEATURE] "
+labels: ["Kind/Feature"]
+---
+
+### Problem Statement
+Is your feature request related to a problem? Please describe. (e.g., I am frustrated when...)
+
+### Proposed Solution
+A clear and concise description of what you want to happen.
+
+### Alternative Solutions
+A clear and concise description of any alternative solutions or features you have considered.
+
+### Additional Context
+Add any other context, screenshots, or mockup ideas about the feature request here.

.gitea/pull_request_template.md

@@ -0,0 +1,14 @@
+## Description
+Please include a summary of the changes and which issue is fixed.
+
+Closes # (Issue Number)
+
+## Type of Change
+- [ ] Bug fix (non-breaking change which fixes an issue)
+- [ ] New feature (non-breaking change which adds functionality)
+- [ ] Chore / Refactoring (code cleanup or configuration updates)
+
+## Testing Environment
+- [ ] Verified via local development server
+- [ ] Verified compilation inside the Docker container
+- [ ] All unit tests passing successfully

.gitea/workflows/release-docker.yaml

@@ -0,0 +1,43 @@
+name: Build and Push Docker Image on Release
+
+on:
+  release:
+    types: [published]
+
+jobs:
+  build-and-push:
+    runs-on: docker-builder
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Enable QEMU for multi-arch builds
+        run: |
+          docker run --privileged --rm tonistiigi/binfmt --install all
+
+      - name: Create and use Docker Buildx builder
+        run: |
+          docker buildx create --name miauinv-builder --use || docker buildx use miauinv-builder
+          docker buildx inspect --bootstrap
+
+      - name: Log in to Gitea Container Registry
+        run: |
+          echo "${{ secrets.REGISTRY_TOKEN }}" | docker login git.miaurizius.de \
+            --username "${{ secrets.REGISTRY_USER }}" \
+            --password-stdin
+
+      - name: Prepare Docker image tags
+        run: |
+          IMAGE_REPO="$(echo "git.miaurizius.de/${{ gitea.repository }}" | tr '[:upper:]' '[:lower:]')"
+          echo "IMAGE_REPO=$IMAGE_REPO" >> "$GITHUB_ENV"
+
+      - name: Build and push multi-arch Docker image
+        run: |
+          docker buildx build \
+            --platform linux/amd64,linux/arm64 \
+            --file ./Dockerfile \
+            --tag "$IMAGE_REPO:latest" \
+            --tag "$IMAGE_REPO:${{ gitea.event.release.tag_name }}" \
+            --push \
+            .

.gitea/workflows/test-and-lint.yaml

@@ -0,0 +1,33 @@
+name: test-and-lint
+
+on:
+  pull_request:
+    branches: [main]
+  push:
+    branches: [main]
+
+jobs:
+  test-and-lint:
+    runs-on: go-1.26
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Check formatting
+        run: |
+          files="$(gofmt -l .)"
+          if [ -n "$files" ]; then
+            echo "$files"
+            exit 1
+          fi
+
+      - name: Check modules
+        run: |
+          go mod tidy
+          git diff --exit-code go.mod go.sum
+
+      - name: Vet
+        run: go vet ./...
+
+      - name: Test
+        run: go test ./...

.gitignore

@@ -3,3 +3,4 @@ appdata
 *.exe
 *.cmd
 .run
+*.out

CONTRIBUTING.md

@@ -0,0 +1,238 @@
+# Contributing to MiauInv
+
+Thank you for considering a contribution to MiauInv.
+
+MiauInv is a self-hosted/private inventory management system. Contributions are accepted through pull requests only. Direct pushes to the `main` branch are not allowed.
+
+## Contribution Model
+
+All changes must be submitted through pull requests.
+
+This applies to:
+
+- new features,
+- bug fixes,
+- refactoring,
+- documentation updates,
+- CI/CD changes,
+- security improvements,
+- release preparation work.
+
+Contributors should work from a fork of the repository. Changes should be developed in a dedicated branch in the fork and then submitted as a pull request to the upstream repository.
+
+Code snippets, patches, or implementation ideas are only accepted into the project if they are submitted through a pull request.
+
+## Protected Main Branch
+
+The `main` branch is protected.
+
+The following rules apply:
+
+- nobody may push directly to `main`,
+- all changes must go through pull requests,
+- pull requests must target `main` unless a maintainer explicitly requests a different target,
+- every commit in a pull request must be signed,
+- unsigned commits will not be accepted.
+
+## Signed Commits
+
+All commits must be signed.
+
+This is mandatory for:
+
+- commits on feature branches,
+- commits on bugfix branches,
+- commits on chore/refactoring branches,
+- commits in pull requests,
+- release preparation commits.
+
+Pull requests containing unsigned commits must be fixed before they can be merged.
+
+Example:
+
+```bash
+git commit -S -m "feat(auth): add account recovery flow"
+```
+
+To check whether commits are signed:
+
+```bash
+git log --show-signature
+```
+
+If a commit was created without a signature, rewrite or recreate it before opening the pull request.
+
+## Branch Naming
+
+Branches should use lowercase, hyphen-separated descriptions and include the related issue ID where possible.
+
+Recommended format:
+
+```text
+<type>/<issue-id>-<lowercase-description>
+```
+
+Examples:
+
+```text
+feature/5-mfa-support
+bugfix/12-fix-refresh-token-rotation
+chore/18-update-ci-workflow
+docs/21-update-authentication-docs
+refactor/24-clean-up-storage-layer
+```
+
+Common branch types:
+
+| Type | Usage |
+| --- | --- |
+| `feature` | New functionality. |
+| `bugfix` | Bug fixes. |
+| `chore` | Maintenance work, tooling, dependency updates, CI changes. |
+| `docs` | Documentation-only changes. |
+| `refactor` | Code restructuring without functional behavior changes. |
+| `release` | Release preparation branches. |
+
+## Feature and Bugfix Workflow
+
+When working on a feature, bugfix, or other change:
+
+1. Create or choose the related issue.
+2. Fork the repository.
+3. Create a branch in your fork using the branch naming scheme.
+4. Implement the change.
+5. Keep commits signed.
+6. Push the branch to your fork.
+7. Open a pull request against the upstream `main` branch.
+8. Use the pull request template.
+9. Ensure the pull request describes the change and links the issue.
+
+When a feature, bugfix, or chore branch is complete, a pull request may be created from that branch into `main`.
+
+## Pull Requests
+
+Pull requests must:
+
+- use the repository pull request template,
+- describe the change clearly,
+- link the related issue where applicable,
+- contain signed commits only,
+- avoid unrelated changes,
+- keep documentation updated when behavior changes,
+- keep the implementation consistent with the existing code structure.
+
+Pull requests should be focused. A pull request should usually address one feature, one bug, or one maintenance task.
+
+If a pull request changes authentication, authorization, account security, database schema, or deployment behavior, the relevant documentation should be updated in the same pull request.
+
+## Issues
+
+Issues should use the available issue templates whenever possible.
+
+A good issue should include:
+
+- a clear description,
+- expected behavior,
+- actual behavior, if reporting a bug,
+- reproduction steps, if applicable,
+- relevant logs, screenshots, or configuration snippets,
+- the affected version or branch, if known.
+
+Feature requests should describe the use case and the expected behavior instead of only describing an implementation detail.
+
+## Releases
+
+Release preparation work should happen on release branches.
+
+Release branch format:
+
+```text
+release/vX.Y.Z
+```
+
+Example:
+
+```text
+release/v1.0.1
+```
+
+Version identifiers follow the `vX.Y.Z` format, for example:
+
+```text
+v1.0.1
+```
+
+When the changes for a version are complete:
+
+1. finalize the release branch,
+2. open a pull request from the release branch into `main`,
+3. merge the release changes into `main`,
+4. create the release,
+5. update and publish Docker images.
+
+Release branches should only contain changes intended for that release.
+
+## Documentation
+
+Documentation should be updated when a change affects:
+
+- setup,
+- configuration,
+- deployment,
+- API behavior,
+- authentication,
+- authorization,
+- database schema,
+- security behavior,
+- CI/CD behavior.
+
+Documentation should be technical, accurate, and written in English.
+
+## Code Style
+
+Follow the existing project structure and style.
+
+General expectations:
+
+- keep handlers in `handlers/`,
+- keep database access in `storage/`,
+- keep shared types in `models/`,
+- keep authentication helpers in `auth/`,
+- keep frontend behavior in `frontend/assets/js/`,
+- keep server route wiring in `server/`,
+- use clear names,
+- avoid unrelated rewrites,
+- keep changes as small as reasonably possible.
+
+Go code must be formatted with:
+
+```bash
+gofmt -w .
+```
+
+## Validation
+
+Before opening a pull request, run the checks that are relevant to the change.
+
+Recommended commands:
+
+```bash
+gofmt -w .
+go test ./...
+go vet ./...
+```
+
+If the change affects Docker deployment, also verify that the Docker image builds successfully.
+
+## Security-Relevant Changes
+
+Changes affecting authentication, authorization, session handling, 2FA, recovery codes, cookies, rate limiting, or database security should be kept especially focused.
+
+Security-sensitive pull requests should clearly explain:
+
+- what behavior changed,
+- what threat or issue is addressed,
+- whether sessions, tokens, or stored secrets are affected,
+- whether existing users or deployments need migration steps.
+
+Do not include secrets, private keys, real tokens, production database files, or private configuration values in commits or pull requests.

Dockerfile

@@ -11,9 +11,15 @@ COPY . .
 ARG TARGETOS
 ARG TARGETARCH
 
+LABEL org.opencontainers.image.source="https://git.miaurizius.de/miaurizius/miauinv"
+
 RUN CGO_ENABLED=0 GOOS=$TARGETOS GOARCH=$TARGETARCH \
     go build -ldflags "-s -w" -o MiauInv .
 
 FROM scratch
+
 COPY --from=builder /app/MiauInv /MiauInv
+
+COPY --from=builder /app/frontend /frontend
+
 ENTRYPOINT ["/MiauInv"]

README.md

@@ -0,0 +1,344 @@
+# MiauInv
+
+MiauInv is a lightweight inventory, stock, and project allocation management system written in Go. It provides a server-rendered dashboard with HTMX-style page composition, vanilla JavaScript for API interactions, SQLite for persistence, JWT-based sessions, refresh-token rotation, account settings, and optional TOTP-based two-factor authentication and WebAuthn passkey authentication.
+
+The project is designed for self-hosted/private deployments. It is not a full enterprise asset-management platform, but it already covers the main workflows needed for tracking items, locations, stock distribution, and project allocations.
+
+## Contents
+
+- [Features](#features)
+- [Current Status](#current-status)
+- [Technical Stack](#technical-stack)
+- [Architecture](#architecture)
+- [Documentation](#documentation)
+- [Configuration](#configuration)
+- [Routes and API Endpoints](#routes-and-api-endpoints)
+- [Setup](#setup)
+- [Docker Deployment](#docker-deployment)
+- [Reverse Proxy Deployment](#reverse-proxy-deployment)
+- [Security Notes](#security-notes)
+- [Screenshots](#screenshots)
+
+## Features
+
+### Inventory and allocation
+
+- Item management with name, category, description, and total quantity.
+- Location management for physical or logical storage places.
+- Stock mapping between items and locations.
+- Project management for allocating items to projects.
+- Association tracking between projects and item quantities.
+- Dashboard statistics for items, locations, and projects.
+
+### Account and authentication
+
+- User registration, if enabled in the configuration.
+- Password hashing with bcrypt.
+- Signed JWT access tokens.
+- Database-backed refresh tokens with rotation.
+- HTTP-only secure cookies for access and refresh tokens.
+- Account settings page at `/profile/settings`.
+- Passkey registration, login, removal, and full passkey disable from account settings.
+- Username change with password confirmation.
+- Password change with old-password verification and session refresh.
+
+### Two-factor authentication
+
+- Optional TOTP 2FA using authenticator apps.
+- QR-code based setup from the account settings page.
+- Manual setup key fallback if QR scanning is not available.
+- Two-step login flow for accounts with 2FA enabled.
+- Recovery codes generated when 2FA is enabled.
+- Recovery codes are stored only as hashes.
+- Recovery codes can be downloaded as a text file after generation.
+- Recovery codes can be regenerated from account settings.
+- Recovery-code count warnings in account settings.
+- Recovery codes are one-time use.
+- The setup secret is only stored after the first valid authenticator code.
+- Existing refresh sessions are revoked when 2FA is enabled or disabled.
+
+### Passkeys
+
+- WebAuthn-based passkey registration from account settings.
+- Passkey login from the normal sign-in page.
+- Discoverable passkey login without entering a username first.
+- User-verification required for registration and login.
+- Server-side challenge storage using opaque one-time challenge tokens.
+- Passkey removal with current-password confirmation.
+- Full passkey disable with current-password confirmation.
+- Existing refresh sessions are revoked when passkeys are added, removed, or disabled.
+
+## Current Status
+
+MiauInv is an active private project. The current version supports core inventory workflows and account-level security settings. Some areas are intentionally still basic:
+
+- There is no dedicated admin panel yet.
+- Basic in-memory rate limiting protects login, 2FA, refresh, registration, and sensitive account endpoints.
+- Automated testing is currently limited and will be expanded in future releases.
+- The application currently uses native TLS. If deployed behind a reverse proxy, the proxy must connect to the backend over HTTPS or the backend TLS behavior must be adjusted intentionally.
+
+## Technical Stack
+
+| Area | Technology |
+| --- | --- |
+| Backend | Go 1.26 |
+| Routing | Go standard library `net/http` |
+| Database | SQLite via `github.com/glebarez/go-sqlite` |
+| Authentication | JWT via `github.com/golang-jwt/jwt/v5` |
+| Password hashing | bcrypt via `golang.org/x/crypto/bcrypt` |
+| 2FA | TOTP via `github.com/pquerna/otp/totp` |
+| Passkeys | WebAuthn via `github.com/go-webauthn/webauthn` |
+| Frontend | Server-rendered HTML, HTMX-style structure, vanilla JavaScript |
+| Styling | Custom CSS with dark theme variables |
+| Deployment | Docker / Docker Compose |
+
+## Architecture
+
+The codebase is split into small packages with mostly direct responsibilities:
+
+| Path | Responsibility |
+| --- | --- |
+| `main.go` | Application entrypoint. Initializes configuration, database, and server startup. |
+| `server/` | HTTP route registration, TLS listener, and server-level configuration. |
+| `config/` | Runtime configuration file creation and loading. |
+| `auth/` | JWT generation, JWT validation, middleware, role middleware, and password helpers. |
+| `handlers/` | JSON API handlers for authentication, account settings, inventory, locations, projects, stock, and associations. |
+| `storage/` | SQLite schema setup, migrations, and database access helpers. |
+| `models/` | Shared data structures and constants. |
+| `frontend/` | HTML template rendering and static asset serving. |
+| `frontend/assets/js/` | Frontend API client, login flow, token refresh logic, account settings logic, and dashboard actions. |
+| `frontend/htmx/` | HTML views and dashboard content templates. |
+
+## Documentation
+
+More detailed documentation is available in:
+
+- [Authentication](docs/AUTHENTICATION.md)
+- [Database](docs/DATABASE.md)
+- [Security](docs/SECURITY.md)
+- [Contributing](CONTRIBUTING.md)
+
+## Configuration
+
+MiauInv reads `./appdata/config.yaml`. If the file does not exist, the application creates a default configuration on startup.
+
+```yaml
+port: "8080"
+database_path: ./appdata/database.db
+certificate_path: ./appdata/cert.pem
+private_key_path: ./appdata/key.pem
+allow_registration: true
+```
+
+### Configuration fields
+
+| Field | Description |
+| --- | --- |
+| `port` | HTTPS listen port. |
+| `database_path` | SQLite database path. |
+| `certificate_path` | TLS certificate path. |
+| `private_key_path` | TLS private key path. |
+| `allow_registration` | Enables or disables public registration. If false, `/register` renders a blocked-registration page and `/api/register` is not registered. |
+
+### Environment variables
+
+| Variable | Required | Description |
+| --- | --- | --- |
+| `JWT_SECRET` | Yes | Symmetric signing secret for JWTs. Must be at least 32 characters. |
+
+Generate a local development secret with:
+
+```bash
+openssl rand -base64 48
+```
+
+## Routes and API Endpoints
+
+### Frontend routes
+
+| Route | Method | Auth required | Description |
+| --- | --- | --- | --- |
+| `/` | `GET` | No | Landing page. |
+| `/login` | `GET` | No | Login page. Supports password login and the second 2FA step. |
+| `/register` | `GET` | No | Registration page or blocked-registration page, depending on configuration. |
+| `/dashboard` | `GET` | Yes | Dashboard overview. |
+| `/inventory` | `GET` | Yes | Stock and inventory overview. |
+| `/items` | `GET` | Yes | Item management view. |
+| `/locations` | `GET` | Yes | Location management view. |
+| `/projects` | `GET` | Yes | Project management view. |
+| `/profile/settings` | `GET` | Yes | Account settings, password changes, passkey management, 2FA setup, 2FA disable, and recovery-code management. |
+| `/profile/` | `GET` | No | Placeholder page for unfinished profile subpages. |
+| `/assets/*` | `GET` | No | Static CSS/JS assets. Minified CSS/JS variants are generated on request. |
+
+### Authentication and account API
+
+| Endpoint | Method | Auth required | Description |
+| --- | --- | --- | --- |
+| `/api/register` | `POST` | No | Creates a user if registration is enabled. |
+| `/api/login` | `POST` | No | Validates username/password. Returns a full session if 2FA is disabled; otherwise returns a short-lived 2FA challenge token. |
+| `/api/login/2fa` | `POST` | No | Completes login using the 2FA challenge token plus either a TOTP code or a recovery code. |
+| `/api/refresh` | `POST` | No | Rotates a refresh token. Accepts the token from JSON or the `refresh_token` cookie. |
+| `/api/logout` | `POST` | Yes | Revokes refresh tokens for the current user and clears auth cookies. |
+| `/api/profile` | `GET` | Yes | Returns current user metadata, 2FA state, and unused recovery-code count. |
+| `/api/userinfo` | `GET` | Yes | Same user information handler as `/api/profile`. |
+| `/api/account/username` | `POST` | Yes | Changes the current username after password confirmation. |
+| `/api/account/password` | `POST` | Yes | Changes the current password, revokes old refresh tokens, and issues a new session. |
+| `/api/2fa/setup` | `POST` | Yes | Creates a pending TOTP secret and returns `secret`, `setup_token`, `otpauth_url`, and a base64 PNG QR code. |
+| `/api/2fa/enable` | `POST` | Yes | Enables 2FA after validating the temporary setup token and a TOTP code. Replaces recovery codes and revokes old sessions. |
+| `/api/2fa/disable` | `POST` | Yes | Disables 2FA after password and TOTP confirmation. Revokes sessions and clears auth cookies. |
+| `/api/2fa/recovery-codes/regenerate` | `POST` | Yes | Invalidates existing recovery codes and returns a new set after password and TOTP confirmation. |
+| `/api/passkeys` | `GET` | Yes | Lists passkeys registered for the current user. |
+| `/api/passkeys` | `DELETE` | Yes | Removes one passkey after current-password confirmation. |
+| `/api/passkeys/register/options` | `POST` | Yes | Creates a server-side passkey registration challenge after current-password confirmation. |
+| `/api/passkeys/register/finish` | `POST` | Yes | Verifies and stores a new passkey credential. Revokes old sessions and issues a new current session. |
+| `/api/passkeys/login/options` | `POST` | No | Creates a discoverable passkey login challenge. |
+| `/api/passkeys/login/finish` | `POST` | No | Verifies passkey login and issues a full session. |
+| `/api/passkeys/disable` | `POST` | Yes | Deletes all passkeys after current-password confirmation. Revokes old sessions and issues a new current session. |
+
+### Inventory API
+
+| Endpoint | Method | Auth required | Query parameters | Description |
+| --- | --- | --- | --- | --- |
+| `/api/item` | `GET` | Yes | `id` optional | Returns all items with aggregate quantities, or one item by ID. |
+| `/api/item` | `POST` | Yes | None | Creates an item. |
+| `/api/item` | `PUT` | Yes | `id` required | Updates item fields. |
+| `/api/item` | `DELETE` | Yes | `id` required | Deletes an item if no dependent rows block it. |
+| `/api/location` | `GET` | Yes | `id`, `content` optional | Returns all locations, one location, or location contents with `content=true`. |
+| `/api/location` | `POST` | Yes | None | Creates a location. |
+| `/api/location` | `PUT` | Yes | `id` required | Renames a location. |
+| `/api/location` | `DELETE` | Yes | `id` required | Deletes a location if no dependent rows block it. |
+| `/api/project` | `GET` | Yes | `id`, `details` optional | Returns all projects, one project, or project allocations with `details=true`. |
+| `/api/project` | `POST` | Yes | None | Creates a project. |
+| `/api/project` | `PUT` | Yes | `id` required | Updates a project. |
+| `/api/project` | `DELETE` | Yes | `id` required | Deletes a project if no dependent rows block it. |
+| `/api/stock` | `GET` | Yes | `id` optional | Returns stock entries. |
+| `/api/stock` | `POST` | Yes | None | Creates a stock entry. |
+| `/api/stock` | `PUT` | Yes | `id` required | Updates a stock entry. |
+| `/api/stock` | `DELETE` | Yes | `id` required | Deletes a stock entry. |
+| `/api/association` | `GET` | Yes | `id`, `project_id` optional | Returns project-item associations. |
+| `/api/association` | `POST` | Yes | None | Allocates item quantity to a project. |
+| `/api/association` | `PUT` | Yes | `id` required | Updates a project allocation. |
+| `/api/association` | `DELETE` | Yes | `id` required | Removes a project allocation. |
+
+## Setup
+
+### Prerequisites
+
+- Go 1.26.
+- SQLite-compatible environment.
+- OpenSSL or another way to generate TLS certificates for local development.
+- A `JWT_SECRET` with at least 32 characters.
+
+### Generate development TLS files
+
+The server uses `http.ListenAndServeTLS`, so TLS files must exist before startup.
+
+```bash
+mkdir -p appdata
+openssl req -x509 -newkey rsa:4096 \
+  -keyout appdata/key.pem \
+  -out appdata/cert.pem \
+  -days 365 \
+  -nodes \
+  -subj "/CN=localhost"
+```
+
+### Native local run
+
+```bash
+export JWT_SECRET="replace-this-with-a-random-secret-of-at-least-32-chars"
+go mod tidy
+go build -o miauinv .
+./miauinv
+```
+
+Then open:
+
+```text
+https://localhost:8080
+```
+
+## Docker Deployment
+
+The repository contains a multi-stage Dockerfile. The final image is based on `scratch` and contains the compiled binary plus frontend assets.
+
+Example `docker-compose.yaml`:
+
+```yaml
+services:
+  miauinv:
+    image: git.miaurizius.de/miaurizius/miauinv:latest
+    container_name: MiauInv
+    restart: unless-stopped
+    ports:
+      - "8080:8080"
+    environment:
+      - JWT_SECRET=replace-this-with-a-random-secret-of-at-least-32-chars
+    volumes:
+      - ./appdata:/appdata
+```
+
+Start the container:
+
+```bash
+docker compose up -d
+```
+
+View logs:
+
+```bash
+docker compose logs -f
+```
+
+## Reverse Proxy Deployment
+
+MiauInv currently listens with native TLS. If it is deployed behind Caddy or another reverse proxy, the proxy must connect to the backend using HTTPS unless the server code is changed to listen without TLS.
+
+Example Caddy configuration with a self-signed backend certificate:
+
+```caddy
+inv.example.com {
+        encode zstd gzip
+
+        reverse_proxy https://miauinv:8080 {
+                transport http {
+                        tls_insecure_skip_verify
+                }
+        }
+
+        header {
+                X-Content-Type-Options nosniff
+                Referrer-Policy strict-origin-when-cross-origin
+        }
+}
+```
+
+For Docker deployments, place Caddy and MiauInv on the same Docker network and reverse proxy to the service name.
+
+## Security Notes
+
+- JWTs are signed, not encrypted. Normal access and purpose tokens must not contain secrets. The temporary 2FA setup token is a narrow exception because it carries the not-yet-enabled TOTP secret back to the authenticated browser until confirmation.
+- `JWT_SECRET` must be random and private.
+- Access tokens expire after 15 minutes.
+- Refresh tokens expire after 7 days and are rotated on refresh.
+- Refresh tokens and recovery codes are stored in the database as hashes.
+- Passkey credentials store public-key credential data, not private keys. Private keys remain in the authenticator or platform passkey provider.
+- TOTP secrets are currently stored in the database because the server must validate codes. Protect the database file accordingly.
+- Recovery codes are only shown when generated. Users should download or copy them immediately. The UI warns when few unused codes remain.
+- 2FA disable and recovery-code regeneration require both the current password and a valid TOTP code.
+- Basic in-memory rate limiting is enabled for login, passkey ceremonies, 2FA, refresh, registration, and sensitive account endpoints. Use persistent or distributed rate limiting for multi-instance deployments.
+- Automated testing is currently limited. Authentication, 2FA, recovery codes, rate limiting, account settings, and inventory handlers should be covered before production use.
+
+## Screenshots
+
+#### Dashboard
+<img src="docs/img/dashboard.png">
+
+#### Inventory
+<img src="docs/img/inventory.png">
+
+#### Locations
+<img src="docs/img/locations.png">
+
+#### Projects
+<img src="docs/img/projects.png">

ad.html

@@ -0,0 +1,407 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>MiauInv - Modern Inventory & Project Management</title>
+    <style>
+        :root {
+            --bg: #0b0f19;
+            --card: #111827;
+            --border: #1f2937;
+            --text: #f9fafb;
+            --text-muted: #9ca3af;
+            --accent: #3b82f6;
+            --accent-hover: #2563eb;
+            --success: #10b981;
+            --code-bg: #1f2937;
+        }
+
+        * {
+            box-sizing: border-box;
+            margin: 0;
+            padding: 0;
+        }
+
+        body {
+            background-color: var(--bg);
+            color: var(--text);
+            font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+            line-height: 1.6;
+            padding: 0;
+            margin: 0;
+        }
+
+        .navbar {
+            display: flex;
+            justify-content: flex-end;
+            padding: 1rem 2rem;
+            max-width: 1000px;
+            margin: 0 auto;
+        }
+
+        .lang-switch {
+            background: var(--card);
+            border: 1px solid var(--border);
+            color: var(--text);
+            padding: 0.5rem 1rem;
+            border-radius: 8px;
+            font-weight: 600;
+            cursor: pointer;
+            transition: all 0.2s ease;
+        }
+
+        .lang-switch:hover {
+            border-color: var(--accent);
+            color: var(--accent);
+        }
+
+        .container {
+            max-width: 1000px;
+            margin: 0 auto;
+            padding: 0 1.5rem 4rem 1.5rem;
+        }
+
+        header {
+            text-align: center;
+            padding: 3rem 0 3rem 0;
+        }
+
+        .brand {
+            font-size: 3.5rem;
+            font-weight: 800;
+            letter-spacing: -0.04em;
+            margin-bottom: 1rem;
+        }
+
+        .brand span {
+            color: var(--accent);
+        }
+
+        .tagline {
+            font-size: 1.25rem;
+            color: var(--text-muted);
+            max-width: 600px;
+            margin: 0 auto 2.5rem auto;
+        }
+
+        .badge-container {
+            display: flex;
+            justify-content: center;
+            gap: 0.75rem;
+            margin-bottom: 3rem;
+            flex-wrap: wrap;
+        }
+
+        .badge {
+            background: rgba(59, 130, 246, 0.1);
+            color: var(--accent);
+            border: 1px solid rgba(59, 130, 246, 0.2);
+            padding: 0.35rem 0.75rem;
+            border-radius: 999px;
+            font-size: 0.85rem;
+            font-weight: 600;
+        }
+
+        .badge.green {
+            background: rgba(16, 185, 129, 0.1);
+            color: var(--success);
+            border-color: rgba(16, 185, 129, 0.2);
+        }
+
+        .grid {
+            display: grid;
+            grid-template-columns: 1fr;
+            gap: 2rem;
+            margin-bottom: 4rem;
+        }
+
+        @media (min-width: 768px) {
+            .grid {
+                grid-template-columns: 1fr 1fr;
+            }
+        }
+
+        .card {
+            background: var(--card);
+            border: 1px solid var(--border);
+            border-radius: 16px;
+            padding: 2.5rem;
+            box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
+        }
+
+        .card h2 {
+            font-size: 1.5rem;
+            font-weight: 700;
+            margin-bottom: 1.25rem;
+            letter-spacing: -0.02em;
+        }
+
+        .features-list {
+            list-style: none;
+            text-align: left;
+        }
+
+        .features-list li {
+            margin-bottom: 1rem;
+            display: flex;
+            align-items: flex-start;
+            gap: 0.75rem;
+            color: var(--text-muted);
+        }
+
+        .features-list li strong {
+            color: var(--text);
+        }
+
+        .features-list svg {
+            flex-shrink: 0;
+            margin-top: 0.2rem;
+            color: var(--success);
+        }
+
+        .install-section {
+            background: var(--card);
+            border: 1px solid var(--border);
+            border-radius: 16px;
+            padding: 3rem 2rem;
+            text-align: left;
+            box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
+            margin-bottom: 4rem;
+        }
+
+        .install-section h2 {
+            font-size: 1.75rem;
+            margin-bottom: 0.5rem;
+            letter-spacing: -0.02em;
+        }
+
+        .install-section p {
+            color: var(--text-muted);
+            margin-bottom: 2rem;
+        }
+
+        .step {
+            margin-bottom: 2rem;
+        }
+
+        .step h3 {
+            font-size: 1.1rem;
+            margin-bottom: 0.75rem;
+            color: var(--text);
+            display: flex;
+            align-items: center;
+            gap: 0.5rem;
+        }
+
+        .step-num {
+            background: var(--border);
+            width: 24px;
+            height: 24px;
+            border-radius: 50%;
+            display: inline-flex;
+            align-items: center;
+            justify-content: center;
+            font-size: 0.8rem;
+            font-weight: bold;
+        }
+
+        pre {
+            background: var(--bg);
+            border: 1px solid var(--border);
+            padding: 1rem 1.25rem;
+            border-radius: 10px;
+            font-family: monospace;
+            font-size: 0.9rem;
+            color: #e5e7eb;
+            overflow-x: auto;
+            white-space: pre;
+            margin-bottom: 1rem;
+        }
+
+        footer {
+            text-align: center;
+            padding: 3rem 0;
+            color: var(--text-muted);
+            font-size: 0.9rem;
+            border-top: 1px solid var(--border);
+        }
+
+        /* Sprach-Sichtbarkeitsregeln */
+        [lang="de"] { display: none; }
+        html[data-lang="de"] [lang="de"] { display: block; }
+        html[data-lang="de"] [lang="en"] { display: none; }
+
+        html[data-lang="de"] span[lang="de"],
+        html[data-lang="de"] strong[lang="de"] {
+            display: inline;
+        }
+        html[data-lang="en"] span[lang="en"],
+        html[data-lang="en"] strong[lang="en"] {
+            display: inline;
+        }
+    </style>
+</head>
+<body class="lang-en">
+
+<div class="navbar">
+    <button class="lang-switch" id="langBtn" onclick="toggleLanguage()">DE</button>
+</div>
+
+<div class="container">
+    <header>
+        <div class="brand">Miau<span>Inv</span></div>
+        <p class="tagline" lang="en">A secure, light-weight, and minimalistic management system for tracking your inventory stock and project allocations.</p>
+        <p class="tagline" lang="de">Ein sicheres, pfeilschnelles und minimalistisches System für deine Lagerbestände und Projekt-Zuweisungen.</p>
+
+        <div class="badge-container">
+            <span class="badge">Go Backend</span>
+            <span class="badge">HTMX Frontend</span>
+            <span class="badge">SQLite Inside</span>
+            <span class="badge green">Docker Ready</span>
+        </div>
+    </header>
+
+    <div class="grid">
+        <div class="card">
+            <h2 lang="en">Why MiauInv?</h2>
+            <h2 lang="de">Warum MiauInv?</h2>
+            <ul class="features-list">
+                <li>
+                    <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"><polyline points="20 6 9 17 4 12"></polyline></svg>
+                    <span>
+                            <strong lang="en">Zero JS-Overhead:</strong><strong lang="de">Kein JS-Overhead:</strong>
+                            <span lang="en"> Powered by HTMX for an ultra-reactive, dynamic SPA experience without heavy client-side bundles.</span>
+                            <span lang="de"> Dank HTMX extrem reaktiv und dynamisch wie eine SPA, aber ohne tonnenweise schweres JavaScript.</span>
+                        </span>
+                </li>
+                <li>
+                    <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"><polyline points="20 6 9 17 4 12"></polyline></svg>
+                    <span>
+                            <strong lang="en">Live Quantities:</strong><strong lang="de">Live-Verfügbarkeit:</strong>
+                            <span lang="en"> See overall totals, allocated project metrics, and remaining available counts instantly.</span>
+                            <span lang="de"> Siehst sofort den Gesamtbestand, was in Projekten verplant ist und was noch frei zur Verfügung steht.</span>
+                        </span>
+                </li>
+                <li>
+                    <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"><polyline points="20 6 9 17 4 12"></polyline></svg>
+                    <span>
+                            <strong lang="en">Unified Dashboards:</strong><strong lang="de">Orte & Projekte im Blick:</strong>
+                            <span lang="en"> Drill straight down into site boundaries or project lists to inspect stock components with one click.</span>
+                            <span lang="de"> Klicke auf Lagerorte oder aktive Projekte im Dashboard, um direkt den aktuellen Inhalt einzusehen.</span>
+                        </span>
+                </li>
+            </ul>
+        </div>
+
+        <div class="card">
+            <h2 lang="en">Security & Tech Stack</h2>
+            <h2 lang="de">Sicherheit & Tech</h2>
+            <ul class="features-list">
+                <li>
+                    <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"><polyline points="20 6 9 17 4 12"></polyline></svg>
+                    <span>
+                            <strong lang="en">Dual-Token Security:</strong><strong lang="de">Dual-Token Security:</strong>
+                            <span lang="en"> Uses robust cryptographically signed JWT cookies combined with seamless backend refresh token rotations.</span>
+                            <span lang="de"> Zugriffsschutz über sichere, verschlüsselte JWT-Cookies inkl. Refresh-Token-Rotation.</span>
+                        </span>
+                </li>
+                <li>
+                    <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"><polyline points="20 6 9 17 4 12"></polyline></svg>
+                    <span>
+                            <strong lang="en">Native TLS Listener:</strong><strong lang="de">Native TLS Listener:</strong>
+                            <span lang="en"> Out-of-the-box enforced HTTPS transport layer security powered directly by Go's core networking.</span>
+                            <span lang="de"> Enforcierte HTTPS-Verschlüsselung direkt aus dem Go-Core heraus.</span>
+                        </span>
+                </li>
+                <li>
+                    <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"><polyline points="20 6 9 17 4 12"></polyline></svg>
+                    <span>
+                            <strong lang="en">Ultra Lightweight:</strong><strong lang="de">Leichtgewicht:</strong>
+                            <span lang="en"> Runs on absolute minimal system footprint resource margins using an embedded optimized SQLite model.</span>
+                            <span lang="de"> Minimaler Ressourcenverbrauch dank kompilierter Go-Binary und eingebetteter SQLite-Datenbank.</span>
+                        </span>
+                </li>
+            </ul>
+        </div>
+    </div>
+
+    <div class="install-section">
+        <h2 lang="en">Install Your Server</h2>
+        <h2 lang="de">Server installieren</h2>
+
+        <p lang="en">Deploy MiauInv to your server infrastructure or local machine in less than a minute utilizing our streamlined container configurations.</p>
+        <p lang="de">MiauInv lässt sich dank vorkonfiguriertem Docker-Setup innerhalb weniger Sekunden auf deinem Server oder lokalen System starten.</p>
+
+        <div class="step">
+            <h3>
+                <span class="step-num">1</span>
+                <span lang="en">Setup Asset Directories and TLS</span>
+                <span lang="de">Ordner und Zertifikate vorbereiten</span>
+            </h3>
+            <p lang="en">Since MiauInv natively enforces encrypted communication channels, initialize your tracking asset directory and place your TLS files there (or generate a self-signed keypair for testing targets):</p>
+            <p lang="de">Da MiauInv standardmäßig verschlüsseltes HTTPS erzwingt, erstelle den Appdata-Ordner und lege deine SSL-Zertifikate ab (oder generiere ein Self-Signed Cert für Tests):</p>
+            <pre>mkdir -p appdata
+openssl req -x509 -newkey rsa:4096 -keyout appdata/key.pem -out appdata/cert.pem -sha256 -days 365 -nodes -subj "/CN=localhost"</pre>
+        </div>
+
+        <div class="step">
+            <h3>
+                <span class="step-num">2</span>
+                <span lang="en">Configure Docker Compose</span>
+                <span lang="de">Docker Compose Datei anlegen</span>
+            </h3>
+            <p lang="en">Create a <code>docker-compose.yaml</code> layout file in the parent folder, and inject the orchestration service blocks. Ensure your <code>JWT_SECRET</code> environment variable meets the minimum security threshold length requirements:</p>
+            <p lang="de">Erstelle eine <code>docker-compose.yaml</code> im selben Verzeichnis und füge folgenden Inhalt ein. Passe den <code>JWT_SECRET</code>-String an:</p>
+            <pre>services:
+  miauinv:
+    image: git.miaurizius.de/miaurizius/miauinv:latest
+    container_name: MiauInv
+    restart: unless-stopped
+    ports:
+      - "8080:8080"
+    environment:
+      - JWT_SECRET=SECURE_RANDOM_STRING_HERE_MIN_32_CHARS
+    volumes:
+      - ./appdata:/appdata</pre>
+        </div>
+
+        <div class="step">
+            <h3>
+                <span class="step-num">3</span>
+                <span lang="en">Boot the Environment</span>
+                <span lang="de">Container starten</span>
+            </h3>
+            <p lang="en">Fire up the production background workers by executing your infrastructure controls daemon tasks:</p>
+            <p lang="de">Führe nun einfach den Start-Befehl aus, um das Image zu ziehen und im Hintergrund zu starten:</p>
+            <pre>docker-compose up -d</pre>
+
+            <p style="margin-top: 0.5rem;" lang="en">Everything is set up! Your instance is running and fully accessible at <strong>https://localhost:8080</strong>.</p>
+            <p style="margin-top: 0.5rem;" lang="de">Fertig! Dein Server läuft und ist sofort unter <strong>https://localhost:8080</strong> erreichbar.</p>
+        </div>
+    </div>
+
+    <footer>
+        <p lang="en">&copy; 2026 Maurice Larivière.</p>
+        <p lang="de">&copy; 2026 Maurice Larivière.</p>
+    </footer>
+</div>
+
+<script>
+    function setLanguage(lang) {
+        document.documentElement.setAttribute('data-lang', lang);
+        document.getElementById('langBtn').innerText = lang === 'en' ? 'DE' : 'EN';
+        localStorage.setItem('miauinv-lang', lang);
+    }
+
+    function toggleLanguage() {
+        const currentLang = document.documentElement.getAttribute('data-lang') || 'en';
+        const nextLang = currentLang === 'en' ? 'de' : 'en';
+        setLanguage(nextLang);
+    }
+
+    const savedLang = localStorage.getItem('miauinv-lang') || 'en';
+    setLanguage(savedLang);
+</script>
+</body>
+</html>

auth/jwt.go

@@ -1,17 +1,36 @@
 package auth
 
 import (
+	"errors"
 	"time"
 
 	"github.com/golang-jwt/jwt/v5"
 )
 
+const (
+	PurposeTwoFactorLogin = "2fa_login"
+	PurposeTwoFactorSetup = "2fa_setup"
+)
+
 type Claims struct {
 	UserID string `json:"user_id"`
 	Role   string `json:"role"`
 	jwt.RegisteredClaims
 }
 
+type PurposeClaims struct {
+	UserID  string `json:"user_id"`
+	Purpose string `json:"purpose"`
+	jwt.RegisteredClaims
+}
+
+type TwoFactorSetupClaims struct {
+	UserID  string `json:"user_id"`
+	Purpose string `json:"purpose"`
+	Secret  string `json:"secret"`
+	jwt.RegisteredClaims
+}
+
 func GenerateJWT(userID, role string, secret []byte) (string, error) {
 	claims := Claims{
 		UserID: userID,
@@ -25,8 +44,41 @@ func GenerateJWT(userID, role string, secret []byte) (string, error) {
 	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
 	return token.SignedString(secret)
 }
+
+func GeneratePurposeJWT(userID, purpose string, secret []byte, ttl time.Duration) (string, error) {
+	claims := PurposeClaims{
+		UserID:  userID,
+		Purpose: purpose,
+		RegisteredClaims: jwt.RegisteredClaims{
+			ExpiresAt: jwt.NewNumericDate(time.Now().Add(ttl)),
+			IssuedAt:  jwt.NewNumericDate(time.Now()),
+		},
+	}
+
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
+	return token.SignedString(secret)
+}
+
+func GenerateTwoFactorSetupJWT(userID, twoFactorSecret string, secret []byte, ttl time.Duration) (string, error) {
+	claims := TwoFactorSetupClaims{
+		UserID:  userID,
+		Purpose: PurposeTwoFactorSetup,
+		Secret:  twoFactorSecret,
+		RegisteredClaims: jwt.RegisteredClaims{
+			ExpiresAt: jwt.NewNumericDate(time.Now().Add(ttl)),
+			IssuedAt:  jwt.NewNumericDate(time.Now()),
+		},
+	}
+
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
+	return token.SignedString(secret)
+}
+
 func ValidateJWT(tokenStr string, secret []byte) (*Claims, error) {
 	token, err := jwt.ParseWithClaims(tokenStr, &Claims{}, func(token *jwt.Token) (interface{}, error) {
+		if token.Method != jwt.SigningMethodHS256 {
+			return nil, errors.New("unexpected signing method")
+		}
 		return secret, nil
 	})
 	if err != nil {
@@ -35,7 +87,54 @@ func ValidateJWT(tokenStr string, secret []byte) (*Claims, error) {
 
 	claims, ok := token.Claims.(*Claims)
 	if !ok || !token.Valid {
-		return nil, err
+		return nil, errors.New("invalid token")
+	}
+
+	return claims, nil
+}
+
+func ValidatePurposeJWT(tokenStr, expectedPurpose string, secret []byte) (*PurposeClaims, error) {
+	token, err := jwt.ParseWithClaims(tokenStr, &PurposeClaims{}, func(token *jwt.Token) (interface{}, error) {
+		if token.Method != jwt.SigningMethodHS256 {
+			return nil, errors.New("unexpected signing method")
+		}
+		return secret, nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	claims, ok := token.Claims.(*PurposeClaims)
+	if !ok || !token.Valid {
+		return nil, errors.New("invalid token")
+	}
+	if claims.Purpose != expectedPurpose {
+		return nil, errors.New("invalid token purpose")
+	}
+
+	return claims, nil
+}
+
+func ValidateTwoFactorSetupJWT(tokenStr string, secret []byte) (*TwoFactorSetupClaims, error) {
+	token, err := jwt.ParseWithClaims(tokenStr, &TwoFactorSetupClaims{}, func(token *jwt.Token) (interface{}, error) {
+		if token.Method != jwt.SigningMethodHS256 {
+			return nil, errors.New("unexpected signing method")
+		}
+		return secret, nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	claims, ok := token.Claims.(*TwoFactorSetupClaims)
+	if !ok || !token.Valid {
+		return nil, errors.New("invalid token")
+	}
+	if claims.Purpose != PurposeTwoFactorSetup {
+		return nil, errors.New("invalid token purpose")
+	}
+	if claims.Secret == "" {
+		return nil, errors.New("missing 2FA setup secret")
 	}
 
 	return claims, nil

auth/middleware.go

@@ -10,27 +10,58 @@ type contextKey string
 
 const UserContextKey contextKey = contextKey("user")
 
+// middleware.go
 func AuthMiddleware(secret []byte) func(http.Handler) http.Handler {
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 
-			authHeader := r.Header.Get("Authorization")
-			if authHeader == "" {
-				http.Error(w, "Missing token", http.StatusUnauthorized)
+			if r.URL.Path == "/login" || r.URL.Path == "/register" || r.URL.Path == "/" {
+				next.ServeHTTP(w, r)
 				return
 			}
 
-			tokenStr := strings.TrimPrefix(authHeader, "Bearer ")
+			tokenStr := ""
+			authHeader := r.Header.Get("Authorization")
+
+			if strings.HasPrefix(authHeader, "Bearer ") {
+				tokenStr = strings.TrimPrefix(authHeader, "Bearer ")
+			}
+
+			if tokenStr == "" {
+				cookie, err := r.Cookie("access_token")
+				if err == nil {
+					tokenStr = cookie.Value
+				}
+			}
+
+			if tokenStr == "" {
+				if strings.HasPrefix(r.URL.Path, "/api/") {
+					http.Error(w, "Missing token", http.StatusUnauthorized)
+				} else {
+					http.Redirect(w, r, "/login", http.StatusSeeOther)
+				}
+				return
+			}
 
 			claims, err := ValidateJWT(tokenStr, secret)
 			if err != nil {
+				if strings.HasPrefix(r.URL.Path, "/api/") {
 					http.Error(w, "Invalid token", http.StatusUnauthorized)
+				} else {
+					http.SetCookie(w, &http.Cookie{
+						Name:     "access_token",
+						Value:    "",
+						Path:     "/",
+						MaxAge:   -1,
+						HttpOnly: false,
+					})
+					http.Redirect(w, r, "/login", http.StatusSeeOther)
+				}
 				return
 			}
 
 			ctx := context.WithValue(r.Context(), UserContextKey, claims)
 			next.ServeHTTP(w, r.WithContext(ctx))
-
 		})
 	}
 }

config/config.go

@@ -13,6 +13,7 @@ type Config struct {
 	DatabasePath      string `yaml:"database_path"`
 	CertificatePath   string `yaml:"certificate_path"`
 	PrivateKeyPath    string `yaml:"private_key_path"`
+	AllowRegistration bool   `yaml:"allow_registration"`
 }
 
 const configPath = "./appdata/config.yaml"
@@ -38,6 +39,7 @@ func CheckIfExists() error {
 		DatabasePath:      "./appdata/database.db",
 		CertificatePath:   "./appdata/cert.pem",
 		PrivateKeyPath:    "./appdata/key.pem",
+		AllowRegistration: true,
 	}
 
 	data, err := yaml.Marshal(defaultConfig)

docs/AUTHENTICATION.md

@@ -0,0 +1,265 @@
+# Authentication Architecture
+
+MiauInv uses signed JWT access tokens, database-backed refresh tokens, optional TOTP-based two-factor authentication, and optional WebAuthn passkey authentication. The authentication flow is implemented in the `auth/`, `handlers/`, `storage/`, and `frontend/assets/js/` packages.
+
+JWTs are signed with a symmetric secret from the `JWT_SECRET` environment variable. They are not encrypted. Access tokens and normal purpose tokens should therefore contain identity and authorization metadata only, not secrets. The short-lived 2FA setup token intentionally carries the not-yet-enabled TOTP secret because the same secret is already returned to the authenticated browser for QR/manual setup and is not stored server-side until confirmation.
+
+## Components
+
+| Component | Location | Responsibility |
+| --- | --- | --- |
+| JWT helpers | `auth/jwt.go` | Access-token and purpose-token generation/validation. |
+| Middleware | `auth/middleware.go` | Extracts access tokens from bearer headers or cookies and injects claims into the request context. |
+| Password helpers | `auth/password.go` | bcrypt hashing and verification. |
+| Login/account handlers | `handlers/account.go` | Register, login, 2FA, refresh, logout, account settings, and user metadata. |
+| Passkey handlers | `handlers/passkeys.go` | WebAuthn/passkey registration, login, removal, and disable flows. |
+| Persistent session storage | `storage/storage.go`, `storage/passkeys.go` | Refresh tokens, 2FA state, TOTP secret, recovery-code hashes, passkey credentials, and WebAuthn challenge state. |
+| Frontend auth logic | `frontend/assets/js/auth.js`, `frontend/assets/js/login.js`, `frontend/assets/js/api.js` | Login UI, passkey login, token refresh, account settings, 2FA UI interactions, and passkey UI interactions. |
+
+## Token Types
+
+| Token | Storage/Transport | Lifetime | Purpose |
+| --- | --- | --- | --- |
+| Access token | `access_token` HTTP-only secure cookie and JSON response body | 15 minutes | Authenticates normal API and page requests. |
+| Refresh token | `refresh_token` HTTP-only secure cookie and JSON response body | 7 days | Rotates sessions after access-token expiry. Stored in the database only as a hash. |
+| 2FA challenge token | JSON response from `/api/login` | 5 minutes | Allows `/api/login/2fa` to complete login after password verification. It is purpose-bound to `2fa_login`. |
+| 2FA setup token | JSON response from `/api/2fa/setup` | 10 minutes | Carries the not-yet-enabled TOTP secret until `/api/2fa/enable` validates the first code. It is purpose-bound to `2fa_setup`. |
+| Passkey ceremony token | JSON response from `/api/passkeys/*/options` | 5 minutes | Opaque server-side reference to WebAuthn session data stored in `passkey_challenges`. Used for passkey registration and login. |
+
+## Normal Login Flow Without 2FA
+
+1. Client sends `POST /api/login` with `username` and `password`.
+2. Server loads the user by username.
+3. Server verifies the bcrypt password hash.
+4. If 2FA is disabled, the server issues:
+   - a signed access token,
+   - a high-entropy refresh token,
+   - HTTP-only secure cookies for both tokens,
+   - a JSON response containing the same token values and user metadata.
+5. The refresh token is hashed before being stored in the `refresh_tokens` table.
+
+## Login Flow With 2FA Enabled
+
+1. Client sends `POST /api/login` with `username` and `password`.
+2. Server verifies the password.
+3. If `two_factor_enabled` is true, the server does not issue a full session.
+4. Instead, the server returns:
+
+```json
+{
+  "requires_2fa": true,
+  "two_factor_token": "..."
+}
+```
+
+5. The frontend shows the second login step.
+6. Client sends `POST /api/login/2fa` with:
+
+```json
+{
+  "two_factor_token": "...",
+  "code": "123456"
+}
+```
+
+7. The server validates the purpose token against the expected purpose `2fa_login`.
+8. The server loads the user from the purpose-token claim.
+9. The supplied code is checked as a TOTP code first.
+10. If the TOTP check fails, the supplied value is normalized and checked as a recovery code.
+11. If either check succeeds, the server issues the normal access/refresh token session.
+12. If a recovery code was used, it is marked as used and cannot be used again.
+
+
+## Passkey Registration Flow
+
+Passkeys are managed from `/profile/settings`. Registration requires an authenticated session and current-password confirmation.
+
+1. Client sends `POST /api/passkeys/register/options` with a passkey name and the current password.
+2. Server verifies the password.
+3. Server creates WebAuthn registration options with resident-key and user-verification requirements.
+4. Server stores the WebAuthn session data in `passkey_challenges` and returns only an opaque `session_token` plus the public registration options.
+5. Browser calls `navigator.credentials.create()` with the returned public-key options.
+6. Client sends the browser credential response to `POST /api/passkeys/register/finish`.
+7. Server consumes the one-time challenge, verifies the WebAuthn response, stores the credential, revokes existing refresh sessions, and issues a new current session.
+
+The server stores credential metadata and public-key credential data. It does not store private keys.
+
+## Passkey Login Flow
+
+Passkey login is available from the normal login page.
+
+1. Client sends `POST /api/passkeys/login/options`.
+2. Server creates a discoverable passkey login challenge without requiring a username.
+3. Server stores the WebAuthn session data in `passkey_challenges` and returns an opaque `session_token` plus assertion options.
+4. Browser calls `navigator.credentials.get()` with the returned public-key options.
+5. Client sends the browser assertion response to `POST /api/passkeys/login/finish`.
+6. Server consumes the one-time challenge and verifies the WebAuthn assertion.
+7. The stored credential data is updated after successful login.
+8. Server issues a normal access/refresh session.
+
+Passkey login is treated as a complete phishing-resistant sign-in method. The application requires WebAuthn user verification for passkey registration and login, so a valid passkey assertion is not followed by a separate TOTP challenge.
+
+## Passkey Management
+
+The account settings page supports:
+
+- listing registered passkeys,
+- adding a passkey,
+- removing a single passkey,
+- disabling all passkeys.
+
+Adding, removing, or disabling passkeys revokes existing refresh sessions and issues a fresh session for the current browser. Removing or disabling passkeys requires current-password confirmation.
+
+## TOTP Setup Flow
+
+The account settings page at `/profile/settings` exposes the UI for TOTP setup.
+
+1. Authenticated user calls `POST /api/2fa/setup`.
+2. Server creates a TOTP secret using issuer `MiauInv` and the current username as the account name.
+3. Server creates a short-lived setup token containing the not-yet-enabled TOTP secret.
+4. The secret is not written to `users.two_factor_secret` during setup.
+5. Server returns:
+
+```json
+{
+  "secret": "BASE32SECRET",
+  "setup_token": "...",
+  "otpauth_url": "otpauth://totp/...",
+  "qr_code": "data:image/png;base64,..."
+}
+```
+
+6. The frontend displays the QR code and the manual setup key.
+7. User scans the QR code or enters the secret manually into an authenticator app.
+8. User submits the setup token and a current TOTP code to `POST /api/2fa/enable`.
+9. Server validates the setup token and the TOTP code.
+10. Server stores the TOTP secret, enables 2FA, invalidates any previous recovery codes, and generates a fresh recovery-code set.
+11. Server revokes existing refresh sessions and issues a new current session.
+12. Recovery codes are returned once to the client for download/copying.
+
+## Recovery Codes
+
+Recovery codes are generated when 2FA is enabled and when the user regenerates them. Enabling 2FA deletes any old recovery-code rows before inserting the new set.
+
+Properties:
+
+- Generated with cryptographically secure randomness.
+- Formatted as four groups of five hexadecimal characters.
+- Normalized before hashing by removing spaces and hyphens and lowercasing the value.
+- Stored only as hashes in `two_factor_recovery_codes`.
+- Single-use only.
+- Displayed only immediately after generation/regeneration.
+- Downloaded client-side from the account settings page as `miauinv-recovery-codes.txt`.
+
+Recovery-code login flow:
+
+1. User enters a recovery code in the same field as the TOTP code during the second login step.
+2. Server first attempts normal TOTP validation.
+3. If TOTP validation fails, server hashes the normalized recovery code.
+4. Server updates the matching unused row with `used_at = now`.
+5. If exactly one row was updated, the recovery-code login succeeds.
+
+## Recovery-Code Regeneration
+
+`POST /api/2fa/recovery-codes/regenerate` requires:
+
+```json
+{
+  "password": "current-password",
+  "code": "123456"
+}
+```
+
+The server verifies the current password and a current TOTP code. If both are valid, all previous recovery codes are deleted and a new set is inserted. The new plaintext codes are returned once. The account settings UI warns the user when the number of unused recovery codes is low.
+
+## Disabling 2FA
+
+`POST /api/2fa/disable` requires:
+
+```json
+{
+  "password": "current-password",
+  "code": "123456"
+}
+```
+
+If the password and TOTP code are valid, the server:
+
+1. Sets `two_factor_enabled = 0`.
+2. Clears `two_factor_secret`.
+3. Deletes recovery codes for the user.
+4. Revokes refresh tokens for the user.
+5. Clears authentication cookies.
+
+The frontend redirects the user to `/login` after disabling 2FA because existing sessions are revoked.
+
+## Refresh Token Rotation
+
+`POST /api/refresh` accepts the refresh token either from JSON:
+
+```json
+{
+  "refresh_token": "..."
+}
+```
+
+or from the `refresh_token` cookie.
+
+The server:
+
+1. Hashes the supplied token.
+2. Looks it up in `refresh_tokens`.
+3. Rejects revoked or expired tokens.
+4. Marks the used refresh token as revoked.
+5. Issues a new access token and refresh token.
+6. Stores the new refresh token hash.
+7. Updates the auth cookies.
+
+## Account Settings Security
+
+The account settings page currently supports:
+
+- username changes,
+- password changes,
+- passkey registration,
+- passkey removal,
+- passkey disable,
+- TOTP 2FA setup,
+- TOTP 2FA disable,
+- recovery-code download after generation,
+- recovery-code regeneration.
+
+Username changes require the current password.
+
+Password changes require the current password, reject passwords longer than bcrypt's 72-byte effective limit, revoke existing refresh tokens, and issue a new session.
+
+2FA activation also revokes existing refresh tokens and issues a new session for the current browser. Passkey changes also revoke existing refresh tokens and issue a new current session. Other devices must log in again and complete the configured authentication flow.
+
+## Middleware Behavior
+
+Protected routes use `AuthMiddleware`.
+
+The middleware checks tokens in this order:
+
+1. `Authorization: Bearer <token>` header.
+2. `access_token` cookie.
+
+If no token is found:
+
+- `/api/*` routes receive `401 Unauthorized`.
+- non-API routes redirect to `/login`.
+
+If token validation fails:
+
+- `/api/*` routes receive `401 Unauthorized`.
+- non-API routes clear the access cookie and redirect to `/login`.
+
+## Security Limitations and Follow-up Work
+
+The current implementation is usable for private/self-hosted deployments, but these improvements should be prioritized before exposing it to untrusted public traffic:
+
+- Replace the current in-memory rate limiter with persistent or distributed rate limiting if the app is deployed across multiple instances.
+- Add audit logging for account security changes.
+- Add optional session/device management UI.
+- Consider encrypting TOTP secrets and passkey credential data at rest if the deployment threat model includes database disclosure.
+- Expand tests for all authentication and account settings handlers.

docs/DATABASE.md

@@ -0,0 +1,257 @@
+# Database Documentation
+
+MiauInv uses SQLite for persistent storage. The schema is initialized in `storage.InitDB` and foreign-key enforcement is explicitly enabled with:
+
+```sql
+PRAGMA foreign_keys = ON;
+```
+
+The database stores users, refresh tokens, 2FA recovery codes, passkey credentials, passkey challenge state, inventory items, locations, projects, stock mappings, and project allocations.
+
+## Entity Overview
+
+```text
+[users] 1 ──── N [refresh_tokens]
+[users] 1 ──── N [two_factor_recovery_codes]
+[users] 1 ──── N [passkey_credentials]
+
+[passkey_challenges] stores short-lived WebAuthn ceremony state
+
+[items] 1 ──── N [stock] N ──── 1 [locations]
+[items] 1 ──── N [project_items] N ──── 1 [projects]
+```
+
+## Tables
+
+### `users`
+
+Stores account credentials, roles, and 2FA state.
+
+| Column | Type | Constraints | Description |
+| --- | --- | --- | --- |
+| `id` | `TEXT` | Primary key | User UUID. |
+| `username` | `TEXT` | Not null, unique | Lowercased account name. |
+| `password` | `TEXT` | Not null | bcrypt password hash. |
+| `role` | `TEXT` | Not null | User role, for example `user` or `admin`. |
+| `two_factor_enabled` | `INTEGER` | Not null, default `0` | Boolean flag for TOTP 2FA state. |
+| `two_factor_secret` | `TEXT` | Not null, default `''` | TOTP secret used to validate authenticator codes. Empty when 2FA is disabled. During setup the secret is held in a short-lived signed setup token and is only stored after the first valid TOTP code. |
+
+Migration note: existing databases are migrated with `ALTER TABLE` statements for `two_factor_enabled` and `two_factor_secret` if those columns do not exist yet.
+
+### `refresh_tokens`
+
+Stores refresh-token sessions. Tokens are stored as hashes, not plaintext.
+
+| Column | Type | Constraints | Description |
+| --- | --- | --- | --- |
+| `id` | `TEXT` | Primary key | Refresh-token row UUID. |
+| `user_id` | `TEXT` | Not null, foreign key to `users(id)` | Owning user. |
+| `token_hash` | `TEXT` | Not null | Hash of the refresh token. |
+| `expires_at` | `INTEGER` | Not null | Unix timestamp for expiry. |
+| `created_at` | `INTEGER` | Not null | Unix timestamp for creation. |
+| `revoked` | `INTEGER` | Not null, default `0` | Boolean revocation flag. |
+| `device_info` | `TEXT` | Optional | User-Agent string recorded when the session is created. |
+
+Refresh-token rotation revokes the used refresh token and inserts a new row for the next token.
+
+### `two_factor_recovery_codes`
+
+Stores recovery-code hashes for 2FA fallback login.
+
+| Column | Type | Constraints | Description |
+| --- | --- | --- | --- |
+| `id` | `TEXT` | Primary key | Recovery-code row UUID. |
+| `user_id` | `TEXT` | Not null, foreign key to `users(id)` with `ON DELETE CASCADE` | Owning user. |
+| `code_hash` | `TEXT` | Not null, unique with `user_id` | Hash of the normalized recovery code. |
+| `created_at` | `INTEGER` | Not null | Unix timestamp for creation. |
+| `used_at` | `INTEGER` | Nullable | Unix timestamp when the code was consumed. `NULL` means unused. |
+
+Recovery codes are deleted and replaced when the user regenerates them. A recovery code is consumed with an atomic update that only matches unused codes.
+
+### `passkey_credentials`
+
+Stores WebAuthn passkey credentials for account login. Private keys are not stored by MiauInv; they remain in the authenticator, platform passkey provider, browser, or security key.
+
+| Column | Type | Constraints | Description |
+| --- | --- | --- | --- |
+| `id` | `TEXT` | Primary key | Passkey row UUID. |
+| `user_id` | `TEXT` | Not null, foreign key to `users(id)` with `ON DELETE CASCADE` | Owning user. |
+| `credential_id` | `TEXT` | Not null, unique | Base64url-encoded WebAuthn credential ID. |
+| `name` | `TEXT` | Not null | User-visible passkey name. |
+| `credential_data` | `TEXT` | Not null | Serialized WebAuthn credential data, including public-key material and authenticator metadata. |
+| `created_at` | `INTEGER` | Not null | Unix timestamp for creation. |
+| `last_used_at` | `INTEGER` | Nullable | Unix timestamp when the passkey was last used successfully. |
+
+### `passkey_challenges`
+
+Stores short-lived server-side WebAuthn session data for registration and login ceremonies. The browser receives only an opaque `session_token`.
+
+| Column | Type | Constraints | Description |
+| --- | --- | --- | --- |
+| `token` | `TEXT` | Primary key | Opaque challenge token returned to the client. |
+| `user_id` | `TEXT` | Not null, default `''` | Owning user for registration challenges. Empty for discoverable login challenges. |
+| `ceremony` | `TEXT` | Not null | Challenge type, for example `register` or `login`. |
+| `session_data` | `TEXT` | Not null | Serialized WebAuthn session data. |
+| `expires_at` | `INTEGER` | Not null | Unix timestamp after which the challenge is rejected. |
+
+Challenge rows are consumed once during the finish step and expired rows are cleaned up opportunistically.
+
+### `items`
+
+Stores tracked inventory items.
+
+| Column | Type | Constraints | Description |
+| --- | --- | --- | --- |
+| `id` | `INTEGER` | Primary key, autoincrement | Item ID. |
+| `name` | `TEXT` | Not null | Item name. |
+| `category` | `TEXT` | Optional | Category label. |
+| `description` | `TEXT` | Optional | Item description. |
+| `total_quantity` | `INTEGER` | Not null, default `0` | Global quantity baseline. |
+
+### `locations`
+
+Stores physical or logical storage locations.
+
+| Column | Type | Constraints | Description |
+| --- | --- | --- | --- |
+| `id` | `INTEGER` | Primary key, autoincrement | Location ID. |
+| `name` | `TEXT` | Not null, unique | Location name. |
+
+### `projects`
+
+Stores project contexts for item allocation.
+
+| Column | Type | Constraints | Description |
+| --- | --- | --- | --- |
+| `id` | `INTEGER` | Primary key, autoincrement | Project ID. |
+| `name` | `TEXT` | Not null, unique | Project name. |
+| `description` | `TEXT` | Optional | Project description. |
+
+### `stock`
+
+Maps item quantities to locations.
+
+| Column | Type | Constraints | Description |
+| --- | --- | --- | --- |
+| `id` | `INTEGER` | Primary key, autoincrement | Stock row ID. |
+| `item_id` | `INTEGER` | Not null, foreign key to `items(id)` | Item reference. |
+| `location_id` | `INTEGER` | Not null, foreign key to `locations(id)` | Location reference. |
+| `quantity` | `INTEGER` | Not null | Quantity at this location. |
+
+### `project_items`
+
+Maps item quantities to projects.
+
+| Column | Type | Constraints | Description |
+| --- | --- | --- | --- |
+| `id` | `INTEGER` | Primary key, autoincrement | Association row ID. |
+| `item_id` | `INTEGER` | Not null, foreign key to `items(id)` | Item reference. |
+| `project_id` | `INTEGER` | Not null, foreign key to `projects(id)` | Project reference. |
+| `quantity` | `INTEGER` | Not null | Quantity allocated to the project. |
+
+## Data Integrity
+
+### Foreign keys
+
+Foreign keys are enabled per connection. Because most inventory foreign keys do not define explicit cascade behavior, SQLite blocks deletion of referenced items, locations, or projects while dependent rows exist.
+
+`two_factor_recovery_codes.user_id` and `passkey_credentials.user_id` use `ON DELETE CASCADE`, so deleting a user also deletes their recovery-code and passkey rows.
+
+### Uniqueness
+
+The following values are unique:
+
+- `users.username`
+- `locations.name`
+- `projects.name`
+- `two_factor_recovery_codes(user_id, code_hash)`
+- `passkey_credentials.credential_id`
+
+### Current schema limitations
+
+The current schema does not yet enforce all business rules at the database level. In particular:
+
+- `items.total_quantity` has no explicit `CHECK(total_quantity >= 0)` constraint.
+- `stock.quantity` has no explicit `CHECK(quantity >= 0)` constraint.
+- `project_items.quantity` has no explicit `CHECK(quantity >= 0)` constraint.
+- Duplicate stock rows for the same `(item_id, location_id)` pair are not prevented by a unique constraint.
+- Duplicate project allocations for the same `(item_id, project_id)` pair are not prevented by a unique constraint.
+
+These constraints should be added in a future migration once the desired application behavior is finalized.
+
+## Important Queries and Behaviors
+
+### User lookup
+
+Users can be loaded by lowercased username or ID. Username updates store the new username lowercased.
+
+### Password update
+
+When the password is updated:
+
+1. The new password is bcrypt-hashed.
+2. The `users.password` field is updated.
+3. Existing refresh tokens for that user are revoked.
+4. A new session is issued.
+
+### Passkey registration
+
+When a passkey is registered:
+
+1. The current password is verified.
+2. A WebAuthn registration challenge is stored in `passkey_challenges`.
+3. The finish step consumes the challenge.
+4. The WebAuthn credential is verified.
+5. A row is inserted into `passkey_credentials`.
+6. Existing refresh tokens for the user are revoked.
+7. A new session is issued for the current browser.
+
+### Passkey login
+
+When passkey login completes:
+
+1. A discoverable WebAuthn login challenge is consumed from `passkey_challenges`.
+2. The credential assertion is verified against the stored credential data.
+3. The stored credential data and `last_used_at` value are updated.
+4. A normal access/refresh session is issued.
+
+### Passkey removal
+
+When a passkey is removed or all passkeys are disabled:
+
+1. The current password is verified.
+2. The matching passkey row, or all rows for the user, are deleted.
+3. Existing refresh tokens for the user are revoked.
+4. A new session is issued for the current browser.
+
+### 2FA enable
+
+When 2FA is enabled:
+
+1. The temporary setup token is validated.
+2. The supplied TOTP code is validated against the setup secret.
+3. Existing recovery codes are deleted.
+4. New recovery-code hashes are inserted.
+5. `users.two_factor_enabled` is set to `1` and `users.two_factor_secret` is set to the confirmed secret.
+6. Existing refresh tokens are revoked and a new session is issued for the current browser.
+
+### 2FA disable
+
+When 2FA is disabled:
+
+1. `two_factor_enabled` is set to `0`.
+2. `two_factor_secret` is cleared.
+3. Recovery-code rows for the user are deleted.
+4. Refresh tokens for the user are revoked.
+
+### Recovery-code use
+
+A recovery code is consumed with an update equivalent to:
+
+```sql
+UPDATE two_factor_recovery_codes
+SET used_at = ?
+WHERE user_id = ? AND code_hash = ? AND used_at IS NULL;
+```
+
+The login succeeds only if exactly one row is updated.

docs/SECURITY.md

@@ -0,0 +1,97 @@
+# Security Notes
+
+This document summarizes the current security-relevant behavior of MiauInv. It is intended as implementation documentation, not as a guarantee that the application is production-ready for untrusted public deployments.
+
+## Authentication
+
+MiauInv uses signed JWT access tokens, database-backed refresh tokens, optional TOTP-based two-factor authentication, and optional WebAuthn passkeys.
+
+JWTs are signed with `JWT_SECRET`. They are not encrypted. Normal access tokens and purpose tokens should therefore contain only identity and authorization metadata.
+
+The short-lived 2FA setup token is a narrow exception: it carries the not-yet-enabled TOTP secret until the first authenticator code is validated. This avoids storing the setup secret in the database before 2FA is confirmed.
+
+## Passwords
+
+Passwords are hashed with bcrypt. Password updates require the current password. New passwords longer than bcrypt's effective 72-byte limit are rejected.
+
+When a password is changed:
+
+1. The new password is bcrypt-hashed.
+2. The stored password hash is updated.
+3. Existing refresh tokens for the user are revoked.
+4. A new session is issued for the current browser.
+
+## Sessions
+
+Access tokens expire after 15 minutes. Refresh tokens expire after 7 days.
+
+Refresh tokens are stored only as hashes in the database. Refresh-token rotation revokes the used refresh token and inserts a new token hash.
+
+Security-sensitive account changes revoke existing refresh-token sessions.
+
+## Cookies
+
+Authentication cookies are set as HTTP-only secure cookies using `SameSite=Lax`.
+
+Because the cookies are marked `Secure`, local development should use HTTPS. If the application is placed behind a reverse proxy, the deployment should preserve HTTPS semantics between the user and the proxy.
+
+## Two-Factor Authentication
+
+TOTP 2FA is optional per account.
+
+The setup flow returns a QR code, a manual setup key, and a short-lived setup token. The TOTP secret is stored only after the user submits a valid code from their authenticator app.
+
+When 2FA is enabled:
+
+1. Any previous recovery codes are deleted.
+2. A new recovery-code set is generated.
+3. The TOTP secret is stored.
+4. Existing refresh sessions are revoked.
+5. A new current session is issued.
+
+When 2FA is disabled:
+
+1. The TOTP secret is cleared.
+2. Recovery codes are deleted.
+3. Existing refresh sessions are revoked.
+4. Authentication cookies are cleared.
+
+## Recovery Codes
+
+Recovery codes are generated with cryptographically secure randomness and stored only as hashes.
+
+They are displayed only immediately after generation or regeneration. They cannot be recovered later because the plaintext values are not stored.
+
+Recovery codes are single-use. During login, a submitted value is first checked as a TOTP code. If that fails, the value is normalized, hashed, and matched against unused recovery-code hashes.
+
+The account settings UI warns the user when the remaining unused recovery-code count is low.
+
+## Passkeys
+
+Passkeys use WebAuthn public-key credentials. The server stores credential metadata and public-key material, but not private keys. Private keys remain controlled by the authenticator, browser, operating system, or security key.
+
+Passkey registration requires the current account password. Registration uses a server-side challenge stored in `passkey_challenges` and returned to the browser only as an opaque challenge token. The browser response is verified before the credential is stored.
+
+Passkey login creates a one-time server-side challenge. The login flow uses discoverable passkeys and does not require entering a username first. User verification is required for passkey registration and login.
+
+Passkey login is treated as a complete phishing-resistant sign-in method. Because passkey registration and login require WebAuthn user verification, the server issues a normal session after a valid passkey assertion instead of asking for an additional TOTP code.
+
+When passkeys are added, removed, or disabled, existing refresh sessions are revoked and a fresh current session is issued.
+
+Passkey ceremonies require HTTPS except for localhost. Reverse proxy deployments must preserve the correct public `Host`, `X-Forwarded-Host`, and `X-Forwarded-Proto` information so that the relying party origin and ID match the browser-visible origin.
+
+## Rate Limiting
+
+Basic in-memory rate limiting protects login, passkey ceremonies, 2FA, refresh, registration, and sensitive account endpoints.
+
+This is suitable for a single-instance private deployment. It is not sufficient for multi-instance deployments because limiter state is process-local. A public or multi-instance deployment should use persistent or distributed rate limiting at the application, reverse proxy, or infrastructure layer.
+
+## Known Limitations
+
+- Automated testing is currently limited.
+- TOTP secrets are stored in the database after confirmation because the server must validate future codes.
+- Passkey credential metadata and public-key data are stored in the database after registration.
+- TOTP secrets are not encrypted at rest.
+- There is no dedicated session/device management UI yet.
+- There is no audit log for account security changes yet.
+- The current rate limiter is process-local and memory-only.

frontend/assets/css/dashboard.css

@@ -0,0 +1,344 @@
+.dashboard-layout {
+    justify-content: flex-start;
+    align-items: stretch;
+    padding: 0;
+}
+
+main {
+    max-width: 1400px;
+    width: 100%;
+    margin: 0 auto;
+    padding: 2rem;
+    flex: 1;
+}
+
+.page-header h1 {
+    font-size: 2.2rem;
+    font-weight: 700;
+    letter-spacing: -0.03em;
+    margin-bottom: 2rem;
+    color: var(--text);
+}
+
+header {
+    width: 100%;
+    border-bottom: 1px solid var(--border);
+    background: rgba(31, 41, 55, 0.8);
+    backdrop-filter: blur(12px);
+    position: sticky;
+    top: 0;
+    z-index: 50;
+}
+
+.nav-container {
+    max-width: 1400px;
+    margin: 0 auto;
+    padding: 0 2rem;
+    height: 4.5rem;
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+}
+
+.nav-left {
+    display: flex;
+    align-items: center;
+    gap: 3rem;
+    height: 100%;
+}
+
+.brand {
+    font-weight: 800;
+    font-size: 1.4rem;
+    letter-spacing: -0.03em;
+}
+
+.brand span {
+    color: var(--accent);
+}
+
+nav {
+    display: flex;
+    gap: 1.5rem;
+    height: 100%;
+}
+
+nav a {
+    color: var(--text-muted);
+    text-decoration: none;
+    font-size: 0.95rem;
+    font-weight: 500;
+    display: inline-flex;
+    align-items: center;
+    border-bottom: 2px solid transparent;
+    padding: 0 0.25rem;
+    transition: color 0.2s ease, border-color 0.2s ease;
+}
+
+nav a:hover, nav a.active {
+    color: var(--text);
+    border-color: var(--accent);
+}
+
+.profile-dropdown {
+    position: relative;
+    display: flex;
+    align-items: center;
+    height: 100%;
+}
+
+.profile-trigger {
+    background: none;
+    border: none;
+    display: flex;
+    align-items: center;
+    gap: 0.75rem;
+    color: var(--text);
+    cursor: pointer;
+    padding: 0.5rem;
+    border-radius: 8px;
+    transition: background-color 0.2s ease;
+}
+
+.profile-trigger:hover {
+    background-color: rgba(255, 255, 255, 0.05);
+}
+
+.avatar {
+    width: 2.2rem;
+    height: 2.2rem;
+    background-color: var(--accent);
+    color: #ffffff;
+    border-radius: 50%;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    font-weight: 600;
+    font-size: 0.9rem;
+}
+
+.username {
+    font-size: 0.95rem;
+    font-weight: 500;
+    display: none;
+}
+
+@media (min-width: 640px) {
+    .username {
+        display: block;
+    }
+}
+
+.dropdown-menu {
+    position: absolute;
+    top: calc(100% - 0.5rem);
+    right: 0;
+    width: 220px;
+    background: #1f2937;
+    border: 1px solid var(--border);
+    border-radius: 12px;
+    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.5);
+    display: none;
+    flex-direction: column;
+    padding: 0.5rem 0;
+    z-index: 100;
+}
+
+.profile-dropdown:hover .dropdown-menu,
+.dropdown-menu.show {
+    display: flex;
+}
+
+.dropdown-menu a, .logout-btn {
+    width: 100%;
+    padding: 0.75rem 1.25rem;
+    font-size: 0.95rem;
+    color: var(--text-muted);
+    text-decoration: none;
+    text-align: left;
+    background: none;
+    border: none;
+    cursor: pointer;
+    transition: background-color 0.15s ease, color 0.15s ease;
+    box-sizing: border-box;
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+}
+
+.dropdown-menu a:hover {
+    background-color: rgba(255, 255, 255, 0.05);
+    color: var(--text);
+}
+
+.dropdown-divider {
+    border: 0;
+    border-top: 1px solid var(--border);
+    margin: 0.5rem 0;
+}
+
+.logout-btn {
+    color: #ef4444;
+    font-weight: 500;
+}
+
+.logout-btn:hover {
+    background-color: rgba(239, 68, 68, 0.1);
+    color: #f87171;
+}
+
+.stats-grid {
+    display: grid;
+    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
+    gap: 1.5rem;
+    margin-bottom: 2rem;
+}
+
+.stat-card {
+    background: var(--card);
+    border: 1px solid var(--border);
+    border-radius: 16px;
+    padding: 1.75rem;
+    display: flex;
+    align-items: center;
+    gap: 1.5rem;
+    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
+    transition: transform 0.2s ease, box-shadow 0.2s ease;
+}
+
+.stat-card:hover {
+    transform: translateY(-2px);
+    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.2);
+}
+
+.stat-icon {
+    width: 3.5rem;
+    height: 3.5rem;
+    border-radius: 12px;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+}
+
+.stat-info h2 {
+    font-size: 2rem;
+    font-weight: 700;
+    letter-spacing: -0.03em;
+    margin: 0;
+    color: var(--text);
+    line-height: 1.2;
+}
+
+.stat-info p {
+    color: var(--text-muted);
+    font-size: 0.9rem;
+    font-weight: 500;
+    text-transform: uppercase;
+    letter-spacing: 0.05em;
+    margin: 0 0 0.25rem 0;
+}
+
+.action-bar {
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+    gap: 1rem;
+    margin-bottom: 1.5rem;
+}
+
+.search-input {
+    max-width: 320px;
+}
+
+.table-container {
+    width: 100%;
+    background: var(--card);
+    border: 1px solid var(--border);
+    border-radius: 16px;
+    overflow: hidden;
+    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
+}
+
+table {
+    width: 100%;
+    border-collapse: collapse;
+    text-align: left;
+    font-size: 0.95rem;
+}
+
+th {
+    background: #111827;
+    color: var(--text-muted);
+    font-weight: 600;
+    padding: 1.25rem 1.5rem;
+    font-size: 0.85rem;
+    text-transform: uppercase;
+    letter-spacing: 0.05em;
+    border-bottom: 1px solid var(--border);
+}
+
+td {
+    padding: 1.25rem 1.5rem;
+    border-bottom: 1px solid var(--border);
+    color: var(--text);
+}
+
+tr:last-child td {
+    border-bottom: none;
+}
+
+tr:hover td {
+    background: rgba(255, 255, 255, 0.02);
+}
+
+#modal {
+    position: fixed;
+    z-index: 100;
+}
+
+@media (max-width: 768px) {
+    .menu-trigger {
+        display: flex;
+        align-items: center;
+        justify-content: center;
+        background: none;
+        border: 1px solid var(--border);
+        color: var(--text);
+        padding: 0.5rem;
+        border-radius: 8px;
+        cursor: pointer;
+    }
+
+    #main-nav {
+        display: none;
+        flex-direction: column;
+        position: absolute;
+        top: 4.5rem;
+        left: 0;
+        width: 100%;
+        background: rgba(17, 24, 39, 0.95);
+        backdrop-filter: blur(12px);
+        padding: 1rem;
+        z-index: 1000;
+        border-bottom: 1px solid var(--border);
+    }
+
+    #main-nav.show {
+        display: flex;
+    }
+
+    #main-nav a {
+        padding: 1rem;
+        border-bottom: 1px solid var(--border);
+    }
+
+    #main-nav a:last-child {
+        border-bottom: none;
+    }
+}
+
+@media (min-width: 769px) {
+    .menu-trigger {
+        display: none;
+    }
+}

frontend/assets/css/error404.css

@@ -0,0 +1,14 @@
+/* error404.css */
+.error-code {
+    font-size: 6rem;
+    font-weight: 800;
+    color: var(--accent);
+    margin: 0;
+    line-height: 1;
+}
+
+@media(max-width:768px){
+    .error-code {
+        font-size: 4.5rem;
+    }
+}

frontend/assets/css/home.css

@@ -0,0 +1,16 @@
+/* home.css */
+.brand-title {
+    font-size: 2.25rem !important;
+    font-weight: 800 !important;
+    letter-spacing: -0.04em !important;
+}
+
+.brand-title span {
+    color: var(--accent);
+}
+
+.home-actions {
+    display: flex;
+    flex-direction: column;
+    gap: 0.85rem;
+}

frontend/assets/css/register-blocked.css

@@ -0,0 +1,108 @@
+:root {
+    --bg: #111827;
+    --card: #1f2937;
+    --border: #374151;
+    --text: #f9fafb;
+    --text-muted: #9ca3af;
+    --accent: #3b82f6;
+    --accent-hover: #2563eb;
+    --success: #10b981;
+    --error: #ef4444;
+}
+
+* {
+    box-sizing: border-box;
+    margin: 0;
+    padding: 0;
+}
+
+body {
+    min-height: 100vh;
+    background: var(--bg);
+    color: var(--text);
+    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+    display: flex;
+    flex-direction: column;
+}
+
+body:not(.dashboard-layout) {
+    justify-content: center;
+    align-items: center;
+    padding: 1rem;
+}
+
+.card {
+    width: 100%;
+    max-width: 400px;
+    background: var(--card);
+    border: 1px solid var(--border);
+    border-radius: 16px;
+    padding: 2.5rem 2rem;
+    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.3), 0 4px 6px -4px rgba(0, 0, 0, 0.3);
+    text-align: center;
+}
+
+.card h1 {
+    margin: 0 0 0.5rem 0;
+    font-size: 1.75rem;
+    font-weight: 700;
+    letter-spacing: -0.025em;
+}
+
+.card .subtitle {
+    color: var(--text-muted);
+    font-size: 0.95rem;
+    margin-bottom: 2rem;
+}
+
+.btn {
+    display: inline-flex;
+    justify-content: center;
+    align-items: center;
+    width: 100%;
+    padding: 0.85rem;
+    font-size: 1rem;
+    font-weight: 600;
+    border-radius: 10px;
+    border: none;
+    cursor: pointer;
+    text-decoration: none;
+    transition: background-color 0.15s ease, border-color 0.15s ease, transform 0.1s ease;
+}
+
+.btn:active {
+    transform: scale(0.98);
+}
+
+.btn-secondary {
+    background: #1f2937;
+    color: white;
+    border: 1px solid var(--border);
+}
+
+.btn-secondary:hover {
+    background: var(--accent);
+    border-color: var(--accent);
+}
+
+.footer-text {
+    margin-top: 1.5rem;
+    font-size: 0.9rem;
+    color: var(--text-muted);
+}
+
+.message {
+    margin-top: 1.25rem;
+    padding: 0.85rem 1rem;
+    border-radius: 10px;
+    font-size: 0.9rem;
+    line-height: 1.4;
+    text-align: left;
+}
+
+.message.error {
+    background: rgba(239, 68, 68, 0.1);
+    border: 1px solid rgba(239, 68, 68, 0.2);
+    color: var(--error);
+    display: block;
+}

frontend/assets/css/style.css

@@ -1,110 +0,0 @@
-:root {
-    --bg: #111827;
-    --card: #1f2937;
-    --border: #374151;
-    --text: #f9fafb;
-    --accent: #3b82f6;
-}
-
-* {
-    box-sizing: border-box;
-}
-
-body {
-    margin: 0;
-    background: var(--bg);
-    color: var(--text);
-    font-family: system-ui;
-}
-
-nav {
-    display: flex;
-    gap: 1rem;
-
-    padding: 1rem;
-
-    border-bottom: 1px solid var(--border);
-}
-
-nav a {
-    color: white;
-    text-decoration: none;
-}
-
-main {
-    max-width: 1400px;
-
-    margin: auto;
-
-    padding: 2rem;
-}
-
-.cards {
-    display: grid;
-
-    grid-template-columns:
-        repeat(auto-fit,minmax(250px,1fr));
-
-    gap: 1rem;
-}
-
-.card {
-    background: var(--card);
-
-    border: 1px solid var(--border);
-
-    border-radius: 12px;
-
-    padding: 1rem;
-}
-
-table {
-    width: 100%;
-    border-collapse: collapse;
-}
-
-th,
-td {
-    padding: 1rem;
-    text-align: left;
-}
-
-tr {
-    border-bottom: 1px solid var(--border);
-}
-
-input,
-select,
-button {
-
-    background: #1f2937;
-
-    color: white;
-
-    border: 1px solid var(--border);
-
-    border-radius: 8px;
-
-    padding: .8rem;
-}
-
-button {
-    cursor: pointer;
-}
-
-button:hover {
-    background: var(--accent);
-}
-
-@media(max-width:768px){
-
-    nav{
-        flex-wrap:wrap;
-    }
-
-    table{
-        display:block;
-        overflow:auto;
-    }
-
-}

frontend/assets/css/theme.css

@@ -0,0 +1,330 @@
+:root {
+    --bg: #111827;
+    --card: #1f2937;
+    --border: #374151;
+    --text: #f9fafb;
+    --text-muted: #9ca3af;
+    --accent: #3b82f6;
+    --accent-hover: #2563eb;
+    --success: #10b981;
+    --error: #ef4444;
+}
+
+* {
+    box-sizing: border-box;
+    margin: 0;
+    padding: 0;
+}
+
+body {
+    min-height: 100vh;
+    background: var(--bg);
+    color: var(--text);
+    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+    display: flex;
+    flex-direction: column;
+}
+
+body:not(.dashboard-layout) {
+    justify-content: center;
+    align-items: center;
+    padding: 1rem;
+}
+
+.card {
+    width: 100%;
+    max-width: 400px;
+    background: var(--card);
+    border: 1px solid var(--border);
+    border-radius: 16px;
+    padding: 2.5rem 2rem;
+    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.3), 0 4px 6px -4px rgba(0, 0, 0, 0.3);
+    text-align: center;
+}
+
+.card h1 {
+    margin: 0 0 0.5rem 0;
+    font-size: 1.75rem;
+    font-weight: 700;
+    letter-spacing: -0.025em;
+}
+
+.card .subtitle {
+    color: var(--text-muted);
+    font-size: 0.95rem;
+    margin-bottom: 2rem;
+}
+
+.btn {
+    display: inline-flex;
+    justify-content: center;
+    align-items: center;
+    width: 100%;
+    padding: 0.85rem;
+    font-size: 1rem;
+    font-weight: 600;
+    border-radius: 10px;
+    border: none;
+    cursor: pointer;
+    text-decoration: none;
+    transition: background-color 0.15s ease, border-color 0.15s ease, transform 0.1s ease;
+}
+
+.btn:active {
+    transform: scale(0.98);
+}
+
+.btn-primary {
+    background: var(--accent);
+    color: white;
+}
+
+.btn-primary:hover {
+    background: var(--accent-hover);
+}
+
+.btn-secondary {
+    background: #1f2937;
+    color: white;
+    border: 1px solid var(--border);
+}
+
+.btn-secondary:hover {
+    background: var(--accent);
+    border-color: var(--accent);
+}
+
+.form-group {
+    margin-bottom: 1.25rem;
+}
+
+.sr-only {
+    position: absolute;
+    width: 1px;
+    height: 1px;
+    padding: 0;
+    margin: -1px;
+    overflow: hidden;
+    clip: rect(0, 0, 0, 0);
+    border: 0;
+}
+
+input {
+    width: 100%;
+    background: #111827;
+    color: white;
+    border: 1px solid var(--border);
+    border-radius: 10px;
+    padding: 0.85rem 1rem;
+    font-size: 1rem;
+    outline: none;
+    transition: border-color 0.15s ease, box-shadow 0.15s ease;
+}
+
+input:focus {
+    border-color: var(--accent);
+    box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.15);
+}
+
+input::placeholder {
+    color: #4b5563;
+}
+
+
+.password-input-wrapper {
+    position: relative;
+    width: 100%;
+}
+
+.password-input-wrapper input {
+    padding-right: 3rem;
+}
+
+.password-toggle {
+    position: absolute;
+    top: 50%;
+    right: 0.45rem;
+    width: 2.25rem;
+    height: 2.25rem;
+    transform: translateY(-50%);
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
+    color: var(--text-muted);
+    background: transparent;
+    border: 1px solid transparent;
+    border-radius: 8px;
+    cursor: pointer;
+    transition: color 0.15s ease, background-color 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease;
+}
+
+.password-toggle:hover {
+    color: var(--text);
+    background: rgba(255, 255, 255, 0.06);
+}
+
+.password-toggle:focus-visible {
+    outline: none;
+    border-color: var(--accent);
+    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
+}
+
+.password-toggle svg {
+    width: 1.15rem;
+    height: 1.15rem;
+    pointer-events: none;
+}
+
+.footer-text {
+    margin-top: 1.5rem;
+    font-size: 0.9rem;
+    color: var(--text-muted);
+}
+
+.footer-text a {
+    color: var(--accent);
+    text-decoration: none;
+}
+
+.footer-text a:hover {
+    text-decoration: underline;
+}
+
+.message {
+    display: none;
+    margin-top: 1.25rem;
+    padding: 0.85rem 1rem;
+    border-radius: 10px;
+    font-size: 0.9rem;
+    line-height: 1.4;
+    text-align: left;
+}
+
+.message.error {
+    background: rgba(239, 68, 68, 0.1);
+    border: 1px solid rgba(239, 68, 68, 0.2);
+    color: var(--error);
+}
+
+.message.success {
+    background: rgba(16, 185, 129, 0.1);
+    border: 1px solid rgba(16, 185, 129, 0.2);
+    color: var(--success);
+}
+
+.modal {
+    position: fixed;
+    top: 0;
+    left: 0;
+    width: 100%;
+    height: 100%;
+    background: rgba(17, 24, 39, 0.7);
+    backdrop-filter: blur(4px);
+    display: none;
+    justify-content: center;
+    align-items: center;
+    z-index: 1000;
+}
+
+.modal.show {
+    display: flex;
+}
+
+.modal-content {
+    background: var(--card);
+    border: 1px solid var(--border);
+    border-radius: 16px;
+    padding: 2rem;
+    width: 90%;
+    max-width: 500px;
+    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.3);
+    position: relative;
+    transform: translateY(20px);
+    opacity: 0;
+    animation: modalSlideIn 0.3s forwards ease-out;
+}
+
+@keyframes modalSlideIn {
+    to {
+        transform: translateY(0);
+        opacity: 1;
+    }
+}
+
+.modal-content h2 {
+    margin-top: 0;
+    margin-bottom: 1.5rem;
+    font-size: 1.5rem;
+}
+
+.button-group {
+    display: flex;
+    gap: 1rem;
+    margin-top: 2rem;
+}
+
+.danger-btn {
+    background: rgba(239, 68, 68, 0.1) !important;
+    color: var(--error) !important;
+    border: 1px solid rgba(239, 68, 68, 0.2) !important;
+}
+
+.danger-btn:hover {
+    background: var(--error) !important;
+    color: white !important;
+}
+
+.table-loader {
+    padding: 3rem;
+    text-align: center;
+    color: var(--text-muted);
+}
+
+.modal-split {
+    display: grid;
+    grid-template-columns: 1fr;
+    gap: 2rem;
+    margin-top: 1.5rem;
+}
+
+@media (min-width: 768px) {
+    .modal-split {
+        grid-template-columns: 1fr 1fr;
+    }
+}
+
+.modal-content.large {
+    max-width: 800px;
+}
+
+.inner-table {
+    width: 100%;
+    margin-top: 1rem;
+    border: 1px solid var(--border);
+    border-radius: 8px;
+    overflow: hidden;
+}
+
+.inner-table th, .inner-table td {
+    padding: 0.75rem 1rem;
+    font-size: 0.85rem;
+}
+
+.inner-table th {
+    background: #111827;
+}
+
+.badge {
+    background: rgba(255, 255, 255, 0.05);
+    padding: 0.25rem 0.6rem;
+    border-radius: 999px;
+    font-size: 0.8rem;
+    color: var(--text-muted);
+    border: 1px solid var(--border);
+}
+
+.badge.success {
+    background: rgba(16, 185, 129, 0.1);
+    color: var(--success);
+    border-color: rgba(16, 185, 129, 0.2);
+}

frontend/assets/css/under-construction.css

@@ -0,0 +1,24 @@
+.construction-icon-wrapper {
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
+    width: 80px;
+    height: 80px;
+    background: rgba(59, 130, 246, 0.1); /* Nutzt die var(--accent) Transparenz */
+    border: 1px solid rgba(59, 130, 246, 0.2);
+    border-radius: 50%;
+    margin-bottom: 1.5rem;
+}
+
+.gear-icon {
+    animation: gearRotate 8s linear infinite;
+}
+
+@keyframes gearRotate {
+    0% {
+        transform: rotate(0deg);
+    }
+    100% {
+        transform: rotate(360deg);
+    }
+}

frontend/assets/js/auth.js

@@ -0,0 +1,128 @@
+// auth.js
+(() => {
+    const currentPath = window.location.pathname;
+
+    if (currentPath !== "/" && currentPath !== "/login" && currentPath !== "/register") {
+        return;
+    }
+
+    function getCookie(name) {
+        const value = `; ${document.cookie}`;
+        const parts = value.split(`; ${name}=`);
+        if (parts.length === 2) return parts.pop().split(';').shift();
+        return null;
+    }
+
+    function clearAllAuth() {
+        console.log("Clearing all auth remnants from everywhere...");
+        localStorage.removeItem("access_token");
+        localStorage.removeItem("refresh_token");
+        sessionStorage.removeItem("is_refreshing");
+        document.cookie = "access_token=; path=/; expires=Thu, 01 Jan 1970 00:00:00 UTC; Secure; SameSite=Lax;";
+        document.cookie = "refresh_token=; path=/; expires=Thu, 01 Jan 1970 00:00:00 UTC; Secure; SameSite=Lax;";
+    }
+
+    async function tryTokenRefresh(refreshToken) {
+        if (!refreshToken) return false;
+
+        try {
+            console.log("Sending refresh token to /api/refresh...");
+            const response = await fetch("/api/refresh", {
+                method: "POST",
+                headers: { "Content-Type": "application/json" },
+                body: JSON.stringify({ refresh_token: refreshToken })
+            });
+
+            if (response.ok) {
+                const data = await response.json();
+                localStorage.setItem("access_token", data.access_token);
+                localStorage.setItem("refresh_token", data.refresh_token);
+                document.cookie = `access_token=${data.access_token}; path=/; max-age=900; SameSite=Lax; Secure`;
+                document.cookie = `refresh_token=${data.refresh_token}; path=/; max-age=604800; SameSite=Lax; Secure`;
+                return true;
+            }
+        } catch (err) {
+            console.error("Refresh request failed:", err);
+        }
+
+        return false;
+    }
+
+    async function checkAuth() {
+        const cookieAccessToken = getCookie("access_token");
+        const cookieRefreshToken = getCookie("refresh_token");
+        const localAccessToken = localStorage.getItem("access_token");
+        const localRefreshToken = localStorage.getItem("refresh_token");
+
+        const accessToken = cookieAccessToken || localAccessToken;
+        const refreshToken = cookieRefreshToken || localRefreshToken;
+
+        console.log("Auth check started...");
+        console.log("AccessToken available (Cookie/Local):", !!cookieAccessToken, "/", !!localAccessToken);
+        console.log("RefreshToken available (Cookie/Local):", !!cookieRefreshToken, "/", !!localRefreshToken);
+
+        if (!accessToken && !refreshToken) {
+            console.log("No tokens found in cookies or localStorage. User is a guest.");
+            return;
+        }
+
+        if (accessToken) {
+            try {
+                console.log("Validating token against /api/userinfo...");
+
+                const response = await fetch("/api/userinfo", {
+                    method: "GET",
+                    headers: { "Authorization": `Bearer ${accessToken}` }
+                });
+
+                if (response.ok) {
+                    console.log("Token is perfectly valid!");
+                    sessionStorage.removeItem("is_refreshing");
+
+                    if (!cookieAccessToken) {
+                        document.cookie = `access_token=${accessToken}; path=/; max-age=900; SameSite=Lax; Secure`;
+                    }
+                    if (!cookieRefreshToken && localRefreshToken) {
+                        document.cookie = `refresh_token=${localRefreshToken}; path=/; max-age=604800; SameSite=Lax; Secure`;
+                    }
+
+                    console.log("Redirecting to dashboard...");
+                    window.location.href = "/dashboard";
+                    return;
+                } else {
+                    console.log("Token rejected by /api/userinfo. Status:", response.status);
+                }
+            } catch (err) {
+                console.error("Network error during token verification:", err);
+            }
+        }
+
+        if (sessionStorage.getItem("is_refreshing") === "true") {
+            console.warn("Loop protection triggered! Tokens appear to be corrupt. Clearing storage.");
+            clearAllAuth();
+            return;
+        }
+
+        if (refreshToken) {
+            console.log("Access token has expired. Starting refresh process...");
+            sessionStorage.setItem("is_refreshing", "true");
+
+            const refreshSuccessful = await tryTokenRefresh(refreshToken);
+
+            if (refreshSuccessful) {
+                console.log("Refresh successful! Reloading page to apply cookies...");
+                window.location.reload();
+                return;
+            } else {
+                console.log("Refresh failed. Refresh token has also expired.");
+            }
+        } else {
+            console.log("No refresh token available for recovery.");
+        }
+
+        clearAllAuth();
+        console.log("Authentication completely failed. User remains on login page.");
+    }
+
+    setTimeout(checkAuth, 50);
+})();

frontend/assets/js/login.js

@@ -0,0 +1,253 @@
+// login.js
+document.addEventListener("DOMContentLoaded", () => {
+    const form = document.getElementById("login-form");
+    const errorBox = document.getElementById("error");
+    const usernameInput = document.getElementById("username");
+    const passwordInput = document.getElementById("password");
+    const twoFactorInput = document.getElementById("two-factor-code");
+    const twoFactorGroup = document.getElementById("two-factor-group");
+    const submitButton = document.getElementById("login-submit");
+    const passkeyLoginButton = document.getElementById("passkey-login-button");
+    const passkeyLoginHint = document.getElementById("passkey-login-hint");
+
+    let pendingTwoFactorToken = null;
+
+    if (!form) return;
+
+    setupPasswordVisibilityToggles();
+
+    function showError(message) {
+        errorBox.textContent = message || "Login failed.";
+        errorBox.style.display = "block";
+    }
+
+    function clearError() {
+        errorBox.textContent = "";
+        errorBox.style.display = "none";
+    }
+
+    function setupPasswordVisibilityToggles(root = document) {
+        const eyeIcon = `
+            <svg viewBox="0 0 24 24" aria-hidden="true" focusable="false">
+                <path d="M2.25 12s3.5-6.75 9.75-6.75S21.75 12 21.75 12 18.25 18.75 12 18.75 2.25 12 2.25 12Z" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round"/>
+                <circle cx="12" cy="12" r="2.75" fill="none" stroke="currentColor" stroke-width="1.8"/>
+            </svg>`;
+        const eyeOffIcon = `
+            <svg viewBox="0 0 24 24" aria-hidden="true" focusable="false">
+                <path d="M3 3l18 18" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round"/>
+                <path d="M10.58 10.58A2.75 2.75 0 0 0 13.42 13.42" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round"/>
+                <path d="M7.1 7.7C3.95 9.55 2.25 12 2.25 12s3.5 6.75 9.75 6.75c1.65 0 3.08-.47 4.29-1.15" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round"/>
+                <path d="M9.8 5.55A9.2 9.2 0 0 1 12 5.25c6.25 0 9.75 6.75 9.75 6.75a15.3 15.3 0 0 1-2.3 2.95" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round"/>
+            </svg>`;
+
+        root.querySelectorAll('input[type="password"]').forEach((input) => {
+            if (input.dataset.visibilityToggleAttached === 'true') return;
+            input.dataset.visibilityToggleAttached = 'true';
+
+            let wrapper = input.closest('.password-input-wrapper');
+            if (!wrapper) {
+                wrapper = document.createElement('div');
+                wrapper.className = 'password-input-wrapper';
+                input.parentNode.insertBefore(wrapper, input);
+                wrapper.appendChild(input);
+            }
+
+            const toggle = document.createElement('button');
+            toggle.type = 'button';
+            toggle.className = 'password-toggle';
+            toggle.innerHTML = eyeIcon;
+            toggle.setAttribute('aria-label', `Show ${input.placeholder || 'password'}`);
+            toggle.setAttribute('title', 'Show password');
+
+            toggle.addEventListener('click', () => {
+                const show = input.type === 'password';
+                input.type = show ? 'text' : 'password';
+                toggle.innerHTML = show ? eyeOffIcon : eyeIcon;
+                toggle.setAttribute('aria-label', `${show ? 'Hide' : 'Show'} ${input.placeholder || 'password'}`);
+                toggle.setAttribute('title', show ? 'Hide password' : 'Show password');
+            });
+
+            wrapper.appendChild(toggle);
+        });
+    }
+
+    function storeTokens(data) {
+        localStorage.setItem("access_token", data.access_token);
+        localStorage.setItem("refresh_token", data.refresh_token);
+    }
+
+    function switchToTwoFactorMode(token) {
+        pendingTwoFactorToken = token;
+        usernameInput.disabled = true;
+        passwordInput.disabled = true;
+        if (passkeyLoginButton) passkeyLoginButton.disabled = true;
+        twoFactorGroup.style.display = "block";
+        twoFactorInput.required = true;
+        twoFactorInput.focus();
+        submitButton.textContent = "Verify code";
+    }
+
+    function webauthnSupported() {
+        return window.PublicKeyCredential && navigator.credentials;
+    }
+
+    function base64URLToBuffer(value) {
+        const base64 = value.replace(/-/g, "+").replace(/_/g, "/");
+        const padded = base64.padEnd(base64.length + (4 - base64.length % 4) % 4, "=");
+        const binary = atob(padded);
+        const bytes = new Uint8Array(binary.length);
+        for (let i = 0; i < binary.length; i++) {
+            bytes[i] = binary.charCodeAt(i);
+        }
+        return bytes.buffer;
+    }
+
+    function bufferToBase64URL(buffer) {
+        const bytes = new Uint8Array(buffer);
+        let binary = "";
+        for (const byte of bytes) {
+            binary += String.fromCharCode(byte);
+        }
+        return btoa(binary).replace(/\+/g, "-").replace(/\//g, "_").replace(/=+$/g, "");
+    }
+
+    function prepareCredentialRequestOptions(options) {
+        const publicKey = options.publicKey || options;
+        publicKey.challenge = base64URLToBuffer(publicKey.challenge);
+        if (Array.isArray(publicKey.allowCredentials)) {
+            publicKey.allowCredentials = publicKey.allowCredentials.map((credential) => ({
+                ...credential,
+                id: base64URLToBuffer(credential.id)
+            }));
+        }
+        return publicKey;
+    }
+
+    function credentialToJSON(credential) {
+        const response = credential.response;
+        return {
+            id: credential.id,
+            rawId: bufferToBase64URL(credential.rawId),
+            type: credential.type,
+            response: {
+                clientDataJSON: bufferToBase64URL(response.clientDataJSON),
+                authenticatorData: bufferToBase64URL(response.authenticatorData),
+                signature: bufferToBase64URL(response.signature),
+                userHandle: response.userHandle ? bufferToBase64URL(response.userHandle) : null
+            },
+            clientExtensionResults: credential.getClientExtensionResults()
+        };
+    }
+
+    async function handlePasskeyLogin() {
+        if (!webauthnSupported()) {
+            showError("Passkeys are not supported by this browser.");
+            return;
+        }
+
+        clearError();
+        if (passkeyLoginButton) passkeyLoginButton.disabled = true;
+        submitButton.disabled = true;
+
+        try {
+            const optionsResponse = await fetch("/api/passkeys/login/options", {
+                method: "POST",
+                headers: { "Content-Type": "application/json" },
+                body: JSON.stringify({})
+            });
+            if (!optionsResponse.ok) {
+                throw new Error(await optionsResponse.text());
+            }
+            const optionsData = await optionsResponse.json();
+            const publicKey = prepareCredentialRequestOptions(optionsData.options);
+            const assertion = await navigator.credentials.get({ publicKey });
+            if (!assertion) {
+                throw new Error("Passkey authentication was cancelled.");
+            }
+
+            const finishResponse = await fetch("/api/passkeys/login/finish", {
+                method: "POST",
+                headers: { "Content-Type": "application/json" },
+                body: JSON.stringify({
+                    session_token: optionsData.session_token,
+                    credential: credentialToJSON(assertion)
+                })
+            });
+            if (!finishResponse.ok) {
+                throw new Error(await finishResponse.text());
+            }
+            const data = await finishResponse.json();
+
+            if (data.requires_2fa) {
+                switchToTwoFactorMode(data.two_factor_token);
+                return;
+            }
+
+            storeTokens(data);
+            window.location.href = "/dashboard";
+        } catch (err) {
+            showError(err.message);
+        } finally {
+            if (!pendingTwoFactorToken && passkeyLoginButton) passkeyLoginButton.disabled = false;
+            submitButton.disabled = false;
+        }
+    }
+
+    if (passkeyLoginButton) {
+        if (!webauthnSupported()) {
+            passkeyLoginButton.disabled = true;
+            if (passkeyLoginHint) passkeyLoginHint.textContent = "Passkeys are not supported by this browser.";
+        } else {
+            passkeyLoginButton.addEventListener("click", handlePasskeyLogin);
+        }
+    }
+
+    form.addEventListener("submit", async (e) => {
+        e.preventDefault();
+        clearError();
+        submitButton.disabled = true;
+
+        try {
+            let response;
+
+            if (pendingTwoFactorToken) {
+                response = await fetch("/api/login/2fa", {
+                    method: "POST",
+                    headers: { "Content-Type": "application/json" },
+                    body: JSON.stringify({
+                        two_factor_token: pendingTwoFactorToken,
+                        code: twoFactorInput.value.trim()
+                    })
+                });
+            } else {
+                response = await fetch("/api/login", {
+                    method: "POST",
+                    headers: { "Content-Type": "application/json" },
+                    body: JSON.stringify({
+                        username: usernameInput.value,
+                        password: passwordInput.value
+                    })
+                });
+            }
+
+            if (!response.ok) {
+                const text = await response.text();
+                throw new Error(text);
+            }
+
+            const data = await response.json();
+
+            if (data.requires_2fa) {
+                switchToTwoFactorMode(data.two_factor_token);
+                return;
+            }
+
+            storeTokens(data);
+            window.location.href = "/dashboard";
+        } catch (err) {
+            showError(err.message);
+        } finally {
+            submitButton.disabled = false;
+        }
+    });
+});

frontend/assets/js/register.js

@@ -0,0 +1,43 @@
+// register.js
+document.addEventListener("DOMContentLoaded", () => {
+    const form = document.getElementById("register-form");
+    const msgBox = document.getElementById("message");
+
+    form.addEventListener("submit", async (e) => {
+        e.preventDefault();
+
+        msgBox.style.display = "none";
+        msgBox.className = "message";
+
+        const username = document.getElementById("username").value;
+        const password = document.getElementById("password").value;
+
+        try {
+            const response = await fetch("/api/register", {
+                method: "POST",
+                headers: { "Content-Type": "application/json" },
+                body: JSON.stringify({ username, password })
+            });
+
+            if (!response.ok) {
+                const text = await response.text();
+                throw new Error(text);
+            }
+
+            msgBox.textContent = "Registration successful! Redirecting...";
+            msgBox.classList.add("success");
+            msgBox.style.display = "block";
+
+            form.querySelector("button").disabled = true;
+
+            setTimeout(() => {
+                window.location.href = "/login";
+            }, 1500);
+
+        } catch (err) {
+            msgBox.textContent = err.message;
+            msgBox.classList.add("error");
+            msgBox.style.display = "block";
+        }
+    });
+});

frontend/handler.go

@@ -1,35 +1,205 @@
 package frontend
 
 import (
+	"MiauInv/storage"
 	"html/template"
 	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/tdewolff/minify/v2"
+	"github.com/tdewolff/minify/v2/css"
+	"github.com/tdewolff/minify/v2/js"
 )
 
-var dashbaord = template.Must(template.ParseFiles(
+var dashboard = template.Must(template.ParseFiles(
 	"frontend/htmx/contents/dash/base.html",
 	"frontend/htmx/contents/dash/dashboard.html"))
+
+var inventory = template.Must(template.ParseFiles(
+	"frontend/htmx/contents/dash/base.html",
+	"frontend/htmx/contents/dash/inventory.html"))
+
+var item = template.Must(template.ParseFiles(
+	"frontend/htmx/contents/dash/base.html",
+	"frontend/htmx/contents/dash/itemlist.html"))
+
+var locations = template.Must(template.ParseFiles(
+	"frontend/htmx/contents/dash/base.html",
+	"frontend/htmx/contents/dash/locations.html"))
+
+var projects = template.Must(template.ParseFiles(
+	"frontend/htmx/contents/dash/base.html",
+	"frontend/htmx/contents/dash/projects.html"))
+
+var accountSettings = template.Must(template.ParseFiles(
+	"frontend/htmx/contents/dash/base.html",
+	"frontend/htmx/contents/dash/account_settings.html"))
+
 var home = template.Must(template.ParseFiles("frontend/htmx/home.html"))
 
 func Home(w http.ResponseWriter, r *http.Request) {
+	if r.URL.Path != "/" {
+		http.ServeFile(w, r, "frontend/htmx/404.html")
+		return
+	}
+
 	w.Header().Set("Content-Type", "text/html")
 	err := home.Execute(w, struct {
 		Name string
 	}{
-		Name: "Miau",
+		Name: "Home",
+	})
+	if err != nil {
+		return
+	}
+}
+func Dashboard(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "text/html")
+
+	var itemHive, projectHive, locationHive int
+
+	err := storage.DB.QueryRow("SELECT COUNT(*) FROM items").Scan(&itemHive)
+	if err != nil {
+		http.Error(w, "Failed to count items", http.StatusInternalServerError)
+		return
+	}
+
+	err = storage.DB.QueryRow("SELECT COUNT(*) FROM projects").Scan(&projectHive)
+	if err != nil {
+		http.Error(w, "Failed to count projects", http.StatusInternalServerError)
+		return
+	}
+
+	err = storage.DB.QueryRow("SELECT COUNT(*) FROM locations").Scan(&locationHive)
+	if err != nil {
+		http.Error(w, "Failed to count locations", http.StatusInternalServerError)
+		return
+	}
+
+	err = dashboard.ExecuteTemplate(w, "base.html", struct {
+		Title string
+		Stats struct {
+			Items     int
+			Projects  int
+			Locations int
+		}
+	}{
+		Title: "Dashboard",
+		Stats: struct {
+			Items     int
+			Projects  int
+			Locations int
+		}{
+			Items:     itemHive,
+			Projects:  projectHive,
+			Locations: locationHive,
+		},
+	})
+	if err != nil {
+		return
+	}
+}
+func Inventory(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "text/html")
+	err := inventory.ExecuteTemplate(w, "base.html", struct {
+		Title string
+	}{
+		Title: "Inventory",
+	})
+	if err != nil {
+		return
+	}
+}
+func Items(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "text/html")
+	err := item.ExecuteTemplate(w, "base.html", struct {
+		Title string
+	}{
+		Title: "Items",
+	})
+	if err != nil {
+		return
+	}
+}
+func Locations(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "text/html")
+	err := locations.ExecuteTemplate(w, "base.html", struct {
+		Title string
+	}{
+		Title: "Locations",
+	})
+	if err != nil {
+		return
+	}
+}
+func Projects(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "text/html")
+	err := projects.ExecuteTemplate(w, "base.html", struct {
+		Title string
+	}{
+		Title: "Projects",
+	})
+	if err != nil {
+		return
+	}
+}
+func AccountSettings(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "text/html")
+	err := accountSettings.ExecuteTemplate(w, "base.html", struct {
+		Title string
+	}{
+		Title: "Account Settings",
 	})
 	if err != nil {
 		return
 	}
 }
 
-func Dashboard(w http.ResponseWriter, r *http.Request) {
-	w.Header().Set("Content-Type", "text/html")
-	err := dashbaord.Execute(w, struct {
-		Title string
-	}{
-		Title: "Miau",
-	})
+var minifier *minify.M
+
+func init() {
+	minifier = minify.New()
+	// Füge die Minifier für CSS und JS hinzu
+	minifier.AddFunc("text/css", css.Minify)
+	minifier.AddFunc("text/javascript", js.Minify)
+}
+func Assets(w http.ResponseWriter, r *http.Request) {
+	path := strings.TrimPrefix(r.URL.Path, "/assets/")
+	fullPath := filepath.Join("frontend/assets", path)
+
+	w.Header().Set("Cache-Control", "public, max-age=3600")
+
+	var mimeType string
+	if strings.HasSuffix(path, ".min.js") {
+		mimeType = "text/javascript"
+		fullPath = strings.Replace(fullPath, ".min.js", ".js", 1)
+	} else if strings.HasSuffix(path, ".min.css") {
+		mimeType = "text/css"
+		fullPath = strings.Replace(fullPath, ".min.css", ".css", 1)
+	}
+
+	info, err := os.Stat(fullPath)
+	if err != nil || info.IsDir() {
+		http.Error(w, "Asset not found", http.StatusNotFound)
+		return
+	}
+
+	if mimeType != "" {
+		content, err := os.ReadFile(fullPath)
 		if err != nil {
+			http.Error(w, "Internal server error", http.StatusInternalServerError)
+			return
+		}
+
+		minifiedContent, err := minifier.Bytes(mimeType, content)
+		if err == nil {
+			w.Header().Set("Content-Type", mimeType)
+			w.Write(minifiedContent)
 			return
 		}
 	}
+
+	http.ServeFile(w, r, fullPath)
+}

frontend/htmx/404.html

@@ -0,0 +1,23 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>404 - Page Not Found | MiauInv</title>
+    <link rel="stylesheet" href="/assets/css/theme.min.css">
+    <link rel="stylesheet" href="/assets/css/error404.min.css">
+</head>
+<body>
+
+<main class="card">
+    <div class="error-code">404</div>
+    <h1>Page Not Found</h1>
+    <p class="subtitle" style="margin-bottom: 2rem;">The page you are looking for does not exist or has been moved to another address.</p>
+
+    <a href="/dashboard" class="btn btn-secondary">
+        Back to Dashboard
+    </a>
+</main>
+
+</body>
+</html>

frontend/htmx/contents/dash/account_settings.html

@@ -0,0 +1,172 @@
+{{ define "content" }}
+<div class="page-header">
+    <h1>Account Settings</h1>
+</div>
+
+<div id="account-settings-content">
+    <div id="account-settings-message" class="message" style="display: none; margin-bottom: 1.5rem;"></div>
+
+    <div class="modal-split" style="align-items: start;">
+        <div class="card" style="max-width: 100%; text-align: left; padding: 1.5rem;">
+            <h2 style="font-size: 1.25rem; margin-bottom: 0.5rem; color: var(--text);">Profile</h2>
+            <p style="color: var(--text-muted); margin-bottom: 1.5rem;">Change your username.</p>
+
+            <form id="username-form" onsubmit="saveAccountUsername(event)">
+                <div class="form-group">
+                    <label for="settings-username" style="display:block; color: var(--text-muted); font-size: 0.9rem; margin-bottom: 0.5rem;">Username</label>
+                    <input type="text" id="settings-username" placeholder="Username" required>
+                </div>
+                <div class="form-group">
+                    <label for="settings-username-password" style="display:block; color: var(--text-muted); font-size: 0.9rem; margin-bottom: 0.5rem;">Current password</label>
+                    <input type="password" id="settings-username-password" placeholder="Confirm with current password" required autocomplete="current-password">
+                </div>
+                <button type="submit" class="btn btn-primary">Save username</button>
+            </form>
+        </div>
+
+        <div class="card" style="max-width: 100%; text-align: left; padding: 1.5rem;">
+            <h2 style="font-size: 1.25rem; margin-bottom: 0.5rem; color: var(--text);">Password</h2>
+            <p style="color: var(--text-muted); margin-bottom: 1.5rem;">Change your password. You will receive a fresh session afterwards.</p>
+
+            <form id="password-form" onsubmit="saveAccountPassword(event)">
+                <div class="form-group">
+                    <label for="settings-current-password" style="display:block; color: var(--text-muted); font-size: 0.9rem; margin-bottom: 0.5rem;">Current password</label>
+                    <input type="password" id="settings-current-password" placeholder="Current password" required autocomplete="current-password">
+                </div>
+                <div class="form-group">
+                    <label for="settings-new-password" style="display:block; color: var(--text-muted); font-size: 0.9rem; margin-bottom: 0.5rem;">New password</label>
+                    <input type="password" id="settings-new-password" placeholder="New password" required autocomplete="new-password">
+                </div>
+                <div class="form-group">
+                    <label for="settings-confirm-password" style="display:block; color: var(--text-muted); font-size: 0.9rem; margin-bottom: 0.5rem;">Confirm new password</label>
+                    <input type="password" id="settings-confirm-password" placeholder="Confirm new password" required autocomplete="new-password">
+                </div>
+                <button type="submit" class="btn btn-primary">Change password</button>
+            </form>
+        </div>
+    </div>
+
+    <div class="card" style="max-width: 100%; text-align: left; padding: 1.5rem; margin-top: 1.5rem;">
+        <div style="display: flex; justify-content: space-between; align-items: flex-start; gap: 1rem; flex-wrap: wrap;">
+            <div>
+                <h2 style="font-size: 1.25rem; margin-bottom: 0.5rem; color: var(--text);">Two-factor authentication</h2>
+                <p id="two-factor-status" style="color: var(--text-muted); margin-bottom: 1rem;">Loading 2FA status...</p>
+            </div>
+            <span id="two-factor-badge" class="badge">Unknown</span>
+        </div>
+
+        <div id="two-factor-disabled-panel" style="display: none;">
+            <p style="color: var(--text-muted); margin-bottom: 1rem;">Use an authenticator app. You can scan the QR code or enter the setup key manually.</p>
+            <button type="button" class="btn btn-primary" style="width: auto; padding: 0.6rem 1.2rem;" onclick="startTwoFactorSetup()">Start 2FA setup</button>
+
+            <div id="two-factor-setup-panel" style="display: none; margin-top: 1.5rem; padding-top: 1.5rem; border-top: 1px solid var(--border);">
+                <div class="modal-split" style="align-items: start;">
+                    <div>
+                        <h3 style="font-size: 1rem; margin-bottom: 0.75rem; color: var(--text);">Scan QR code</h3>
+                        <img id="two-factor-qr" alt="2FA QR code" style="display: none; width: 220px; height: 220px; background: white; padding: 0.5rem; border-radius: 12px;">
+                    </div>
+                    <div>
+                        <h3 style="font-size: 1rem; margin-bottom: 0.75rem; color: var(--text);">Manual setup</h3>
+                        <p style="color: var(--text-muted); margin-bottom: 0.75rem;">If you do not want to scan the QR code, enter this key manually in your authenticator app.</p>
+                        <code id="two-factor-secret" style="display:block; word-break: break-all; background:#111827; border:1px solid var(--border); border-radius:10px; padding:0.85rem; color:var(--text);"></code>
+                        <a id="two-factor-otpauth" href="#" style="display:block; color: var(--accent); margin-top:0.75rem; word-break: break-all;">Open otpauth URL</a>
+                    </div>
+                </div>
+
+                <form id="two-factor-enable-form" onsubmit="enableTwoFactor(event)" style="margin-top: 1.5rem;">
+                    <div class="form-group">
+                        <label for="two-factor-enable-code" style="display:block; color: var(--text-muted); font-size: 0.9rem; margin-bottom: 0.5rem;">Authenticator code</label>
+                        <input type="text" id="two-factor-enable-code" inputmode="numeric" placeholder="123456" required autocomplete="one-time-code">
+                    </div>
+                    <button type="submit" class="btn btn-primary" style="width: auto; padding: 0.6rem 1.2rem;">Enable 2FA</button>
+                </form>
+            </div>
+        </div>
+
+        <div id="two-factor-enabled-panel" style="display: none;">
+            <p style="color: var(--text-muted); margin-bottom: 0.5rem;">Recovery codes remaining: <strong id="recovery-codes-remaining">0</strong></p>
+            <p id="recovery-codes-warning" class="message error" style="display: none; margin-bottom: 1rem;">You are running low on recovery codes. Generate and download new codes soon.</p>
+
+            <div id="recovery-codes-panel" style="display: none; margin-bottom: 1.5rem; padding: 1rem; border: 1px solid var(--border); border-radius: 12px; background: #111827;">
+                <h3 style="font-size: 1rem; margin-bottom: 0.75rem; color: var(--text);">Recovery codes</h3>
+                <p style="color: var(--text-muted); margin-bottom: 1rem;">Save these now. They are shown only once.</p>
+                <pre id="recovery-codes-list" style="white-space: pre-wrap; word-break: break-word; color: var(--text); background: rgba(255,255,255,0.03); border: 1px solid var(--border); border-radius: 10px; padding: 1rem; margin-bottom: 1rem;"></pre>
+                <button type="button" class="btn btn-primary" style="width: auto; padding: 0.6rem 1.2rem;" onclick="downloadRecoveryCodes()">Download recovery codes</button>
+            </div>
+
+            <div class="modal-split" style="align-items: start;">
+                <div>
+                    <h3 style="font-size: 1rem; margin-bottom: 0.75rem; color: var(--text);">Regenerate recovery codes</h3>
+                    <p style="color: var(--text-muted); margin-bottom: 1rem;">This invalidates all existing recovery codes.</p>
+                    <form id="recovery-regenerate-form" onsubmit="regenerateRecoveryCodes(event)">
+                        <div class="form-group">
+                            <input type="password" id="recovery-password" placeholder="Current password" required autocomplete="current-password">
+                        </div>
+                        <div class="form-group">
+                            <input type="text" id="recovery-code" inputmode="numeric" placeholder="Authenticator code" required autocomplete="one-time-code">
+                        </div>
+                        <button type="submit" class="btn btn-secondary">Generate new recovery codes</button>
+                    </form>
+                </div>
+
+                <div>
+                    <h3 style="font-size: 1rem; margin-bottom: 0.75rem; color: var(--text);">Disable 2FA</h3>
+                    <p style="color: var(--text-muted); margin-bottom: 1rem;">Disabling 2FA revokes your active refresh sessions.</p>
+                    <form id="two-factor-disable-form" onsubmit="disableTwoFactor(event)">
+                        <div class="form-group">
+                            <input type="password" id="two-factor-disable-password" placeholder="Current password" required autocomplete="current-password">
+                        </div>
+                        <div class="form-group">
+                            <input type="text" id="two-factor-disable-code" inputmode="numeric" placeholder="Authenticator code" required autocomplete="one-time-code">
+                        </div>
+                        <button type="submit" class="btn btn-secondary danger-btn">Disable 2FA</button>
+                    </form>
+                </div>
+            </div>
+        </div>
+    </div>
+
+    <div class="card" style="max-width: 100%; text-align: left; padding: 1.5rem; margin-top: 1.5rem;">
+        <div style="display: flex; justify-content: space-between; align-items: flex-start; gap: 1rem; flex-wrap: wrap;">
+            <div>
+                <h2 style="font-size: 1.25rem; margin-bottom: 0.5rem; color: var(--text);">Passkeys</h2>
+                <p id="passkey-status" style="color: var(--text-muted); margin-bottom: 1rem;">Loading passkey status...</p>
+            </div>
+            <span id="passkey-badge" class="badge">Unknown</span>
+        </div>
+
+        <p style="color: var(--text-muted); margin-bottom: 1rem;">Use device-bound or synced passkeys for phishing-resistant sign-in. Passkeys are protected by your browser, operating system, or security key.</p>
+
+        <div id="passkey-unsupported-message" class="message error" style="display: none; margin-bottom: 1rem;">This browser does not support passkeys.</div>
+
+        <div id="passkey-list" style="display: grid; gap: 0.75rem; margin-bottom: 1.5rem;"></div>
+
+        <div class="modal-split" style="align-items: start;">
+            <div>
+                <h3 style="font-size: 1rem; margin-bottom: 0.75rem; color: var(--text);">Add passkey</h3>
+                <p style="color: var(--text-muted); margin-bottom: 1rem;">Confirm with your current password, then follow your browser's passkey prompt.</p>
+                <form id="passkey-add-form" onsubmit="addPasskey(event)">
+                    <div class="form-group">
+                        <input type="text" id="passkey-name" placeholder="Passkey name" autocomplete="off">
+                    </div>
+                    <div class="form-group">
+                        <input type="password" id="passkey-add-password" placeholder="Current password" required autocomplete="current-password">
+                    </div>
+                    <button type="submit" class="btn btn-primary" style="width: auto; padding: 0.6rem 1.2rem;">Add passkey</button>
+                </form>
+            </div>
+
+            <div>
+                <h3 style="font-size: 1rem; margin-bottom: 0.75rem; color: var(--text);">Disable passkeys</h3>
+                <p style="color: var(--text-muted); margin-bottom: 1rem;">This removes all stored passkeys and revokes active refresh sessions.</p>
+                <form id="passkey-disable-form" onsubmit="disablePasskeys(event)">
+                    <div class="form-group">
+                        <input type="password" id="passkey-disable-password" placeholder="Current password" required autocomplete="current-password">
+                    </div>
+                    <button type="submit" class="btn btn-secondary danger-btn">Disable all passkeys</button>
+                </form>
+            </div>
+        </div>
+    </div>
+</div>
+{{ end }}

frontend/htmx/contents/dash/base.html

@@ -1,23 +1,52 @@
-<!DOCTYPE html>
-<html lang="de">
+{{ define "base.html" }}
+<html lang="en">
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <title>{{ .Title }}</title>
-
+    <title>{{ .Title }} | MiauInv</title>
     <script src="https://unpkg.com/htmx.org@2.0.4"></script>
-
-    <link rel="stylesheet" href="/static/css/app.css">
+    <script src="/assets/js/api.min.js"></script>
+    <link rel="stylesheet" href="/assets/css/theme.min.css">
+    <link rel="stylesheet" href="/assets/css/dashboard.min.css">
 </head>
+<body class="dashboard-layout">
 
-<body>
+<header>
+    <div class="nav-container">
+        <div class="nav-left">
+            <div class="brand">Miau<span>Inv</span></div>
 
-<nav>
+            <button class="menu-trigger" id="menu-btn" aria-label="Menu">
+                <svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><line x1="3" y1="12" x2="21" y2="12"></line><line x1="3" y1="6" x2="21" y2="6"></line><line x1="3" y1="18" x2="21" y2="18"></line></svg>
+            </button>
+
+            <nav id="main-nav">
                 <a href="/dashboard">Dashboard</a>
-    <a href="/items">Inventar</a>
-    <a href="/projects">Projekte</a>
-    <a href="/locations">Orte</a>
+                <a href="/inventory">Inventory</a>
+                <a href="/projects">Projects</a>
+                <a href="/locations">Locations</a>
             </nav>
+        </div>
+
+        <div class="profile-dropdown">
+            <button class="profile-trigger" id="profile-btn">
+                <div id="avatar" class="avatar">M</div>
+                <span id="username" class="username">Loading...</span>
+                <svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><polyline points="6 9 12 15 18 9"></polyline></svg>
+            </button>
+            <div class="dropdown-menu" id="dropdown-menu">
+                <a href="/profile/settings">Account Settings</a>
+                <a href="/profile/activity">Activity Log</a>
+                <hr class="dropdown-divider">
+                <button id="logout-btn" class="logout-btn"
+                        hx-post="/api/logout"
+                        hx-on::after-request="window.location.href='/login'">
+                    Log Out
+                </button>
+            </div>
+        </div>
+    </div>
+</header>
 
 <main>
     {{ template "content" . }}
@@ -25,3 +54,4 @@
 
 </body>
 </html>
+{{ end }}

frontend/htmx/contents/dash/dashboard.html

@@ -1,24 +1,110 @@
 {{ define "content" }}
-
-<h1>Dashboard</h1>
-
-<div class="cards">
-
-    <div class="card">
-        <h2>{{ .Stats.Items }}</h2>
-        <p>Items</p>
+<div class="page-header">
+    <h1>Dashboard Overview</h1>
 </div>
 
-    <div class="card">
-        <h2>{{ .Stats.Projects }}</h2>
-        <p>Projekte</p>
+<div class="stats-grid" style="margin-bottom: 2rem; display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 1.5rem;">
+    <div class="stat-card" style="background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 1.5rem; display: flex; align-items: center; gap: 1rem;">
+        <div class="stat-icon" style="background: rgba(59, 130, 246, 0.1); color: var(--accent); padding: 0.75rem; border-radius: 10px; display: flex; align-items: center; justify-content: center;">
+            <svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><polygon points="12 2 2 7 12 12 22 7 12 2"></polygon><polyline points="2 17 12 22 22 17"></polyline><polyline points="2 12 12 17 22 12"></polyline></svg>
+        </div>
+        <div class="stat-info">
+            <p style="color: var(--text-muted); font-size: 0.9rem; margin: 0;">Total Items</p>
+            <h2 style="font-size: 1.5rem; font-weight: 700; margin: 0;">
+                {{ if .Stats }}{{ .Stats.Items }}{{ else }}0{{ end }}
+            </h2>
+        </div>
     </div>
 
-    <div class="card">
-        <h2>{{ .Stats.Locations }}</h2>
-        <p>Orte</p>
+    <div class="stat-card" style="background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 1.5rem; display: flex; align-items: center; gap: 1rem;">
+        <div class="stat-icon" style="background: rgba(16, 185, 129, 0.1); color: var(--success); padding: 0.75rem; border-radius: 10px; display: flex; align-items: center; justify-content: center;">
+            <svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M22 19a2 2 0 0 1-2 2H4a2 2 0 0 1-2-2V5a2 2 0 0 1 2-2h5l2 3h9a2 2 0 0 1 2 2z"></path></svg>
+        </div>
+        <div class="stat-info">
+            <p style="color: var(--text-muted); font-size: 0.9rem; margin: 0;">Active Projects</p>
+            <h2 style="font-size: 1.5rem; font-weight: 700; margin: 0;">
+                {{ if .Stats }}{{ .Stats.Projects }}{{ else }}0{{ end }}
+            </h2>
+        </div>
     </div>
 
+    <div class="stat-card" style="background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 1.5rem; display: flex; align-items: center; gap: 1rem;">
+        <div class="stat-icon" style="background: rgba(245, 158, 11, 0.1); color: #f59e0b; padding: 0.75rem; border-radius: 10px; display: flex; align-items: center; justify-content: center;">
+            <svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M21 10c0 7-9 13-9 13s-9-6-9-13a9 9 0 0 1 18 0z"></path><circle cx="12" cy="10" r="3"></circle></svg>
+        </div>
+        <div class="stat-info">
+            <p style="color: var(--text-muted); font-size: 0.9rem; margin: 0;">Locations</p>
+            <h2 style="font-size: 1.5rem; font-weight: 700; margin: 0;">
+                {{ if .Stats }}{{ .Stats.Locations }}{{ else }}0{{ end }}
+            </h2>
+        </div>
+    </div>
 </div>
 
+<div class="modal-split">
+    <div class="card" style="max-width: 100%; text-align: left; padding: 1.5rem;">
+        <h2 style="font-size: 1.25rem; margin-bottom: 1rem; color: var(--text);">Locations</h2>
+        <div class="table-container">
+            <table class="inner-table" style="margin-top: 0; border-radius: 8px; width: 100%;">
+                <thead>
+                <tr>
+                    <th style="text-align: left; padding: 0.75rem 1rem; background: #111827;">Name</th>
+                </tr>
+                </thead>
+                <tbody id="dash-locations-body">
+                <tr><td class="table-loader" style="padding: 1.5rem; text-align: center; color: var(--text-muted);">Loading locations...</td></tr>
+                </tbody>
+            </table>
+        </div>
+    </div>
+
+    <div class="card" style="max-width: 100%; text-align: left; padding: 1.5rem;">
+        <h2 style="font-size: 1.25rem; margin-bottom: 1rem; color: var(--text);">Active Projects</h2>
+        <div class="table-container">
+            <table class="inner-table" style="margin-top: 0; border-radius: 8px; width: 100%;">
+                <thead>
+                <tr>
+                    <th style="text-align: left; padding: 0.75rem 1rem; background: #111827;">Project Name</th>
+                </tr>
+                </thead>
+                <tbody id="dash-projects-body">
+                <tr><td class="table-loader" style="padding: 1.5rem; text-align: center; color: var(--text-muted);">Loading projects...</td></tr>
+                </tbody>
+            </table>
+        </div>
+    </div>
+</div>
+
+<div id="dash-details-modal" class="modal">
+    <div class="modal-content">
+        <h2 id="dash-modal-title">Details</h2>
+        <div class="table-container">
+            <table class="inner-table" style="width: 100%;">
+                <thead>
+                <tr>
+                    <th style="text-align: left; padding: 0.75rem 1rem;">Item</th>
+                    <th style="text-align: right; width: 100px; padding: 0.75rem 1rem;">Quantity</th>
+                </tr>
+                </thead>
+                <tbody id="dash-modal-body"></tbody>
+            </table>
+        </div>
+        <div class="button-group">
+            <button type="button" class="btn btn-secondary" onclick="document.getElementById('dash-details-modal').classList.remove('show')">Close</button>
+        </div>
+    </div>
+</div>
+
+<script>
+    if (typeof handleDashboardView === "function") {
+        handleDashboardView();
+    }
+    if (window.htmx) {
+        htmx.on("htmx:afterOnLoad", function() {
+            if (typeof handleDashboardView === "function") {
+                handleDashboardView();
+            }
+        });
+    }
+</script>
 {{ end }}

frontend/htmx/contents/dash/inventory.html

@@ -1,21 +1,88 @@
 {{ define "content" }}
-
-<h1>Inventar</h1>
-
-<input
-        type="search"
-        name="q"
-        placeholder="Suchen..."
-        hx-get="/api/items/search"
-        hx-trigger="keyup changed delay:300ms"
-        hx-target="#items"
->
-
-<div
-        id="items"
-        hx-get="/api/items"
-        hx-trigger="load"
->
+<div class="page-header action-bar">
+    <h1>Inventory</h1>
+    <button class="btn btn-primary" style="width: auto; padding: 0.6rem 1.2rem; font-size: 0.95rem;" onclick="openItemModal()">
+        Add Item
+    </button>
 </div>
 
+<div class="table-container">
+    <table>
+        <thead>
+        <tr>
+            <th>Name</th>
+            <th>Category</th>
+            <th>Total Quantity</th>
+            <th style="text-align: right;">Actions</th>
+        </tr>
+        </thead>
+        <tbody id="items-table-body">
+        <tr><td colspan="4" class="table-loader">Loading inventory...</td></tr>
+        </tbody>
+    </table>
+</div>
+
+<div id="item-modal" class="modal">
+    <div class="modal-content">
+        <h2 id="item-modal-title">New Item</h2>
+        <form id="item-form" onsubmit="saveItem(event)">
+            <input type="hidden" id="item-id">
+            <div class="form-group">
+                <input type="text" id="item-name" placeholder="Item Name" required>
+            </div>
+            <div class="form-group">
+                <input type="text" id="item-category" placeholder="Category" required>
+            </div>
+            <div class="form-group">
+                <input type="text" id="item-desc" placeholder="Description">
+            </div>
+            <div class="button-group">
+                <button type="submit" class="btn btn-primary">Save Item</button>
+                <button type="button" class="btn btn-secondary" onclick="closeModal('item-modal')">Cancel</button>
+            </div>
+        </form>
+    </div>
+</div>
+
+<div id="stock-modal" class="modal">
+    <div class="modal-content large">
+        <h2 id="stock-modal-title">Manage Stock</h2>
+        <div class="modal-split">
+            <div>
+                <h3>Current Locations</h3>
+                <div class="inner-table">
+                    <table>
+                        <thead>
+                        <tr>
+                            <th>Location</th>
+                            <th>Quantity</th>
+                            <th></th>
+                        </tr>
+                        </thead>
+                        <tbody id="stock-table-body">
+                        </tbody>
+                    </table>
+                </div>
+            </div>
+            <div>
+                <h3>Update Stock</h3>
+                <form id="stock-form" onsubmit="saveStock(event)" style="margin-top: 1rem;">
+                    <input type="hidden" id="stock-item-id">
+                    <div class="form-group">
+                        <select id="stock-location" class="search-input" style="width: 100%; padding: 0.85rem 1rem; background: #111827; color: white; border: 1px solid var(--border); border-radius: 10px;" required>
+                            <option value="">Select Location...</option>
+                        </select>
+                    </div>
+                    <div class="form-group">
+                        <input type="number" id="stock-qty" placeholder="Quantity to add/set" required>
+                    </div>
+                    <div class="button-group">
+                        <button type="submit" class="btn btn-primary">Update Stock</button>
+                        <button type="button" class="btn btn-secondary" onclick="closeModal('stock-modal')">Done</button>
+                    </div>
+                </form>
+            </div>
+        </div>
+    </div>
+</div>
 {{ end }}

frontend/htmx/contents/dash/itemlist.html

@@ -1,32 +1,28 @@
 <table>
-
     <thead>
     <tr>
         <th>Name</th>
-        <th>Kategorie</th>
-        <th>Gesamt</th>
-        <th>Frei</th>
+        <th>Category</th>
+        <th>Total</th>
+        <th>Free</th>
+        <th style="text-align: right;">Actions</th>
     </tr>
     </thead>
-
     <tbody>
-
     {{ range . }}
-
     <tr>
-
-        <td>{{ .Name }}</td>
-
-        <td>{{ .Category }}</td>
-
-        <td>{{ .TotalQuantity }}</td>
-
-        <td>{{ .FreeQuantity }}</td>
-
+        <td style="font-weight: 600;">{{ .Name }}</td>
+        <td>
+            <span style="background: rgba(255,255,255,0.05); padding: 0.25rem 0.6rem; border-radius: 999px; font-size: 0.8rem; color: var(--text-muted); border: 1px solid var(--border);">
+                {{ .Category }}
+            </span>
+        </td>
+        <td style="font-family: monospace; font-size: 1.05rem;">{{ .TotalQuantity }}</td>
+        <td style="font-family: monospace; font-size: 1.05rem; color: var(--success);">{{ .FreeQuantity }}</td>
+        <td style="text-align: right;">
+            <button class="btn btn-secondary" style="width: auto; padding: 0.4rem 0.8rem; font-size: 0.85rem;">Edit</button>
+        </td>
     </tr>
-
     {{ end }}
-
     </tbody>
-
 </table>

frontend/htmx/contents/dash/locations.html

@@ -1,11 +1,38 @@
 {{ define "content" }}
-
-<h1>Lagerorte</h1>
-
-<div
-        hx-get="/api/locations"
-        hx-trigger="load"
->
+<div class="page-header action-bar">
+    <h1>Locations</h1>
+    <button class="btn btn-primary" style="width: auto; padding: 0.6rem 1.2rem; font-size: 0.95rem;" onclick="openLocationModal()">
+        Add Location
+    </button>
 </div>
 
+<div class="table-container">
+    <table>
+        <thead>
+        <tr>
+            <th>Name</th>
+            <th style="text-align: right;">Actions</th>
+        </tr>
+        </thead>
+        <tbody id="locations-table-body">
+        <tr><td colspan="2" class="table-loader">Loading locations...</td></tr>
+        </tbody>
+    </table>
+</div>
+
+<div id="location-modal" class="modal">
+    <div class="modal-content">
+        <h2 id="location-modal-title">New Location</h2>
+        <form id="location-form" onsubmit="saveLocation(event)">
+            <input type="hidden" id="location-id">
+            <div class="form-group">
+                <input type="text" id="location-name" placeholder="Location Name" required>
+            </div>
+            <div class="button-group">
+                <button type="submit" class="btn btn-primary">Save Location</button>
+                <button type="button" class="btn btn-secondary" onclick="closeModal('location-modal')">Cancel</button>
+            </div>
+        </form>
+    </div>
+</div>
 {{ end }}

frontend/htmx/contents/dash/projects.html

@@ -1,21 +1,84 @@
 {{ define "content" }}
-
-<h1>Projekte</h1>
-
-<button
-        hx-get="/projects/new"
-        hx-target="#modal"
->
-    Neues Projekt
+<div class="page-header action-bar">
+    <h1>Projects</h1>
+    <button class="btn btn-primary" style="width: auto; padding: 0.6rem 1.2rem; font-size: 0.95rem;" onclick="openProjectModal()">
+        New Project
     </button>
-
-<div
-        hx-get="/api/projects"
-        hx-trigger="load"
-        hx-target="this"
->
 </div>
 
-<div id="modal"></div>
+<div class="table-container">
+    <table>
+        <thead>
+        <tr>
+            <th>Name</th>
+            <th>Description</th>
+            <th style="text-align: right;">Actions</th>
+        </tr>
+        </thead>
+        <tbody id="projects-table-body">
+        <tr><td colspan="3" class="table-loader">Loading projects...</td></tr>
+        </tbody>
+    </table>
+</div>
 
+<div id="project-modal" class="modal">
+    <div class="modal-content">
+        <h2 id="project-modal-title">New Project</h2>
+        <form id="project-form" onsubmit="saveProject(event)">
+            <input type="hidden" id="project-id">
+            <div class="form-group">
+                <input type="text" id="project-name" placeholder="Project Name" required>
+            </div>
+            <div class="form-group">
+                <input type="text" id="project-desc" placeholder="Description">
+            </div>
+            <div class="button-group">
+                <button type="submit" class="btn btn-primary">Save Project</button>
+                <button type="button" class="btn btn-secondary" onclick="closeModal('project-modal')">Cancel</button>
+            </div>
+        </form>
+    </div>
+</div>
+
+<div id="association-modal" class="modal">
+    <div class="modal-content large">
+        <h2 id="association-modal-title">Manage Project Items</h2>
+        <div class="modal-split">
+            <div>
+                <h3>Allocated Items</h3>
+                <div class="inner-table">
+                    <table>
+                        <thead>
+                        <tr>
+                            <th>Item</th>
+                            <th>Quantity</th>
+                            <th></th>
+                        </tr>
+                        </thead>
+                        <tbody id="association-table-body">
+                        </tbody>
+                    </table>
+                </div>
+            </div>
+            <div>
+                <h3>Allocate New Item</h3>
+                <form id="association-form" onsubmit="saveAssociation(event)" style="margin-top: 1rem;">
+                    <input type="hidden" id="assoc-project-id">
+                    <div class="form-group">
+                        <select id="assoc-item" class="search-input" style="width: 100%; padding: 0.85rem 1rem; background: #111827; color: white; border: 1px solid var(--border); border-radius: 10px;" required>
+                            <option value="">Select Item...</option>
+                        </select>
+                    </div>
+                    <div class="form-group">
+                        <input type="number" id="assoc-qty" placeholder="Quantity needed" required>
+                    </div>
+                    <div class="button-group">
+                        <button type="submit" class="btn btn-primary">Allocate</button>
+                        <button type="button" class="btn btn-secondary" onclick="closeModal('association-modal')">Done</button>
+                    </div>
+                </form>
+            </div>
+        </div>
+    </div>
+</div>
 {{ end }}

frontend/htmx/home.html

@@ -1,6 +1,26 @@
 <!DOCTYPE html>
-<html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>MiauInv | Private Instance</title>
+    <script src="/assets/js/auth.js"></script>
+    <link rel="stylesheet" href="/assets/css/theme.min.css">
+    <link rel="stylesheet" href="/assets/css/home.min.css">
+</head>
 <body>
-        <h1>Hallo, {{.Name}}!</h1>
+
+<main class="card">
+    <div class="header">
+        <h1 class="brand-title">Miau<span>Inv</span></h1>
+        <p class="subtitle">Private Instance</p>
+    </div>
+
+    <div class="home-actions">
+        <a href="/login" class="btn btn-primary">Sign In</a>
+        <a href="/register" class="btn btn-secondary">Create Account</a>
+    </div>
+</main>
+
 </body>
 </html>

frontend/htmx/login.html

@@ -0,0 +1,51 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Sign In | MiauInv</title>
+
+    <script src="/assets/js/auth.min.js" defer></script>
+    <script src="/assets/js/login.min.js" defer></script>
+
+    <link rel="stylesheet" href="/assets/css/theme.min.css">
+</head>
+<body>
+
+<main class="card">
+    <div class="header">
+        <h1>Welcome back</h1>
+        <p class="subtitle">Sign in to your account</p>
+    </div>
+
+    <form id="login-form">
+        <div class="form-group">
+            <label for="username" class="sr-only">Username</label>
+            <input type="text" id="username" placeholder="Username" autocomplete="username" required>
+        </div>
+
+        <div class="form-group" id="password-group">
+            <label for="password" class="sr-only">Password</label>
+            <input type="password" id="password" placeholder="Password" autocomplete="current-password" required>
+        </div>
+
+        <div class="form-group" id="two-factor-group" style="display: none;">
+            <label for="two-factor-code" class="sr-only">2FA code</label>
+            <input type="text" id="two-factor-code" placeholder="Authenticator or recovery code" autocomplete="one-time-code" inputmode="text" pattern="[0-9A-Za-z\- ]*">
+            <p class="subtitle" style="margin-top: 0.75rem;">Enter your 6-digit authenticator code or one recovery code.</p>
+        </div>
+
+        <button type="submit" id="login-submit" class="btn btn-primary">Sign In</button>
+        <button type="button" id="passkey-login-button" class="btn btn-secondary" style="margin-top: 0.75rem;">Sign in with passkey</button>
+        <p id="passkey-login-hint" class="subtitle" style="margin-top: 0.75rem;">Use a saved passkey from this device, your browser, or a security key. No username is required for passkey sign-in.</p>
+    </form>
+
+    <div id="error" class="message error"></div>
+
+    <p class="footer-text">
+        Don't have an account yet? <a href="/register">Create account</a>
+    </p>
+</main>
+
+</body>
+</html>

frontend/htmx/register-blocked.html

@@ -0,0 +1,26 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Registration Disabled - MiauInv</title>
+    <link rel="stylesheet" href="/assets/css/register-blocked.min.css">
+
+</head>
+<body>
+
+<div class="card">
+    <h1>Registration</h1>
+    <div class="subtitle">Create a new account</div>
+
+    <div class="message error">
+        <strong>Access Denied:</strong> Public registration is currently disabled for this system. Please contact your system administrator to request an account.
+    </div>
+
+    <div class="footer-text">
+        <a class="btn btn-secondary" href="/login" style="margin-top: 1.5rem;">Back to Login</a>
+    </div>
+</div>
+
+</body>
+</html>

frontend/htmx/register.html

@@ -0,0 +1,41 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Register | MiauInv</title>
+    <script src="/assets/js/auth.min.js"></script>
+    <script src="/assets/js/register.min.js"></script>
+    <link rel="stylesheet" href="/assets/css/theme.min.css">
+</head>
+<body>
+
+<main class="card">
+    <div class="header">
+        <h1>Create Account</h1>
+        <p class="subtitle">Register to continue</p>
+    </div>
+
+    <form id="register-form">
+        <div class="form-group">
+            <label for="username" class="sr-only">Username</label>
+            <input type="text" id="username" placeholder="Username" autocomplete="username" required>
+        </div>
+
+        <div class="form-group">
+            <label for="password" class="sr-only">Password</label>
+            <input type="password" id="password" placeholder="Password" autocomplete="new-password" required>
+        </div>
+
+        <button type="submit" class="btn btn-primary">Register</button>
+    </form>
+
+    <div id="message" class="message"></div>
+
+    <p class="footer-text">
+        Already have an account? <a href="/login">Sign in here</a>
+    </p>
+</main>
+
+</body>
+</html>

frontend/htmx/under-construction.html

@@ -0,0 +1,39 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Feature Under Development | MiauInv</title>
+    <link rel="stylesheet" href="/assets/css/theme.min.css">
+    <link rel="stylesheet" href="/assets/css/under-construction.min.css">
+</head>
+<body>
+
+<div class="card">
+    <div class="construction-icon-wrapper">
+        <svg class="gear-icon" width="48" height="48" viewBox="0 0 24 24" fill="none" stroke="var(--accent)" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
+            <circle cx="12" cy="12" r="3"></circle>
+            <path d="M19.4 15a1.65 1.65 0 0 0 .33 1.82l.06.06a2 2 0 1 1-2.83 2.83l-.06-.06a1.65 1.65 0 0 0-1.82-.33 1.65 1.65 0 0 0-1 1.51V21a2 2 0 0 1-4 0v-.09A1.65 1.65 0 0 0 9 19.4a1.65 1.65 0 0 0-1.82.33l-.06.06a2 2 0 1 1-2.83-2.83l.06-.06a1.65 1.65 0 0 0 .33-1.82 1.65 1.65 0 0 0-1.51-1H3a2 2 0 0 1 0-4h.09A1.65 1.65 0 0 0 4.6 9a1.65 1.65 0 0 0-.33-1.82l-.06-.06a2 2 0 1 1 2.83-2.83l.06.06a1.65 1.65 0 0 0 1.82.33H9a1.65 1.65 0 0 0 1-1.51V3a2 2 0 0 1 4 0v.09a1.65 1.65 0 0 0 1 1.51 1.65 1.65 0 0 0 1.82-.33l.06-.06a2 2 0 1 1 2.83 2.83l-.06.06a1.65 1.65 0 0 0-.33 1.82V9a1.65 1.65 0 0 0 1.51 1H21a2 2 0 0 1 0 4h-.09a1.65 1.65 0 0 0-1.51 1z"></path>
+        </svg>
+    </div>
+
+    <h1>Coming Soon</h1>
+    <div class="subtitle">Feature Under Development</div>
+
+    <div class="message success" style="display: block; margin-bottom: 2rem;">
+        <strong>Development in progress!</strong><br>
+        Our team is actively working on this feature to bring you the best experience possible.
+    </div>
+
+    <a href="/dashboard" class="btn btn-secondary">
+        <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" style="margin-right: 8px;"><line x1="19" y1="12" x2="5" y2="12"></line><polyline points="12 19 5 12 12 5"></polyline></svg>
+        Back to Dashboard
+    </a>
+
+    <div class="footer-text">
+        Need urgent assistance? <a href="mailto:maurice@miaurizius.de">Contact Developer</a>
+    </div>
+</div>
+
+</body>
+</html>

go.mod

@@ -4,19 +4,32 @@ go 1.26
 
 require (
 	github.com/glebarez/go-sqlite v1.22.0
+	github.com/go-webauthn/webauthn v0.17.4
 	github.com/golang-jwt/jwt/v5 v5.3.1
-	golang.org/x/crypto v0.52.0
+	github.com/google/uuid v1.6.0
+	github.com/pquerna/otp v1.5.0
+	github.com/tdewolff/minify/v2 v2.24.13
+	golang.org/x/crypto v0.53.0
 	gopkg.in/yaml.v3 v3.0.1
 )
 
 require (
+	github.com/boombuler/barcode v1.1.0 // indirect
 	github.com/dustin/go-humanize v1.0.1 // indirect
-	github.com/google/uuid v1.5.0 // indirect
-	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/fxamacker/cbor/v2 v2.9.2 // indirect
+	github.com/go-viper/mapstructure/v2 v2.5.0 // indirect
+	github.com/go-webauthn/x v0.2.6 // indirect
+	github.com/google/go-tpm v0.9.8 // indirect
+	github.com/mattn/go-isatty v0.0.22 // indirect
+	github.com/ncruces/go-strftime v1.0.0 // indirect
+	github.com/philhofer/fwd v1.2.0 // indirect
 	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
-	golang.org/x/sys v0.45.0 // indirect
-	modernc.org/libc v1.37.6 // indirect
-	modernc.org/mathutil v1.6.0 // indirect
-	modernc.org/memory v1.7.2 // indirect
-	modernc.org/sqlite v1.28.0 // indirect
+	github.com/tdewolff/parse/v2 v2.8.13 // indirect
+	github.com/tinylib/msgp v1.6.4 // indirect
+	github.com/x448/float16 v0.8.4 // indirect
+	golang.org/x/sys v0.46.0 // indirect
+	modernc.org/libc v1.73.0 // indirect
+	modernc.org/mathutil v1.7.1 // indirect
+	modernc.org/memory v1.11.0 // indirect
+	modernc.org/sqlite v1.52.0 // indirect
 )

go.sum

@@ -1,31 +1,100 @@
+github.com/boombuler/barcode v1.0.1-0.20190219062509-6c824513bacc/go.mod h1:paBWMcWSl3LHKBqUq+rly7CNSldXjb2rDl3JlRe0mD8=
+github.com/boombuler/barcode v1.1.0 h1:ChaYjBR63fr4LFyGn8E8nt7dBSt3MiU3zMOZqFvVkHo=
+github.com/boombuler/barcode v1.1.0/go.mod h1:paBWMcWSl3LHKBqUq+rly7CNSldXjb2rDl3JlRe0mD8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
 github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=
+github.com/fxamacker/cbor/v2 v2.9.2 h1:X4Ksno9+x3cz0TZv69ec1hxP/+tymuR8PXQJyDwfh78=
+github.com/fxamacker/cbor/v2 v2.9.2/go.mod h1:vM4b+DJCtHn+zz7h3FFp/hDAI9WNWCsZj23V5ytsSxQ=
 github.com/glebarez/go-sqlite v1.22.0 h1:uAcMJhaA6r3LHMTFgP0SifzgXg46yJkgxqyuyec+ruQ=
 github.com/glebarez/go-sqlite v1.22.0/go.mod h1:PlBIdHe0+aUEFn+r2/uthrWq4FxbzugL0L8Li6yQJbc=
+github.com/go-viper/mapstructure/v2 v2.5.0 h1:vM5IJoUAy3d7zRSVtIwQgBj7BiWtMPfmPEgAXnvj1Ro=
+github.com/go-viper/mapstructure/v2 v2.5.0/go.mod h1:oJDH3BJKyqBA2TXFhDsKDGDTlndYOZ6rGS0BRZIxGhM=
+github.com/go-webauthn/webauthn v0.17.4 h1:KFTSz3R2RYDiUn/0cDi3XTJgFenSG74eKTTHlqWhlxk=
+github.com/go-webauthn/webauthn v0.17.4/go.mod h1:pZk63EE/BdztlmyS4Yc+9H5g4a8blNlbtGmdHQHbZX8=
+github.com/go-webauthn/x v0.2.6 h1:TEyDuQAIiEgYpx60nKiBJIX/5nSUC8LxNbH+uf5U9uk=
+github.com/go-webauthn/x v0.2.6/go.mod h1:45bA7YEqyQhRcQJ/TiBb46Ww8yqHBGvgEhQ3WWF0aDo=
 github.com/golang-jwt/jwt/v5 v5.3.1 h1:kYf81DTWFe7t+1VvL7eS+jKFVWaUnK9cB1qbwn63YCY=
 github.com/golang-jwt/jwt/v5 v5.3.1/go.mod h1:fxCRLWMO43lRc8nhHWY6LGqRcf+1gQWArsqaEUEa5bE=
-github.com/google/pprof v0.0.0-20221118152302-e6195bd50e26 h1:Xim43kblpZXfIBQsbuBVKCudVG457BR2GZFIz3uw3hQ=
-github.com/google/pprof v0.0.0-20221118152302-e6195bd50e26/go.mod h1:dDKJzRmX4S37WGHujM7tX//fmj1uioxKzKxz3lo4HJo=
-github.com/google/uuid v1.5.0 h1:1p67kYwdtXjb0gL0BPiP1Av9wiZPo5A8z2cWkTZ+eyU=
-github.com/google/uuid v1.5.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
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handlers/account.go

@@ -2,20 +2,27 @@ package handlers
 
 import (
 	"MiauInv/auth"
-	"MiauInv/config"
 	"MiauInv/models"
 	"MiauInv/storage"
-	"MiauInv/util"
+	utils "MiauInv/util"
+	"bytes"
+	"crypto/rand"
+	"encoding/base64"
+	"encoding/hex"
 	"encoding/json"
+	"image/png"
 	"log"
 	"net/http"
 	"os"
+	"strings"
 	"time"
+
+	"github.com/pquerna/otp/totp"
 )
 
-var cfg, _ = config.LoadConfig()
+const recoveryCodeWarningThreshold = 3
 
-func Register(w http.ResponseWriter, r *http.Request) {
+func APIRegister(w http.ResponseWriter, r *http.Request) {
 	var user models.User
 	if err := json.NewDecoder(r.Body).Decode(&user); err != nil {
 		log.Println("POST [api/register] " + r.RemoteAddr + ": " + err.Error())
@@ -29,6 +36,12 @@ func Register(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	if len(user.Password) > 72 {
+		log.Println("POST [api/register] User password too long")
+		http.Error(w, "Password exceeds the maximum allowed length of 72 characters", http.StatusUnprocessableEntity)
+		return
+	}
+
 	hashed, err := auth.HashPassword(user.Password)
 	if err != nil {
 		log.Println("POST [api/register] " + r.RemoteAddr + ": " + err.Error())
@@ -48,7 +61,8 @@ func Register(w http.ResponseWriter, r *http.Request) {
 	w.WriteHeader(http.StatusCreated)
 	log.Println("POST [api/register] " + r.RemoteAddr + ": Successfully created user")
 }
-func Login(w http.ResponseWriter, r *http.Request) {
+
+func APILogin(w http.ResponseWriter, r *http.Request) {
 	var creds struct {
 		Username string `json:"username"`
 		Password string `json:"password"`
@@ -79,59 +93,453 @@ func Login(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	accessToken, err := auth.GenerateJWT(user.ID, user.Role, secret)
+	if user.TwoFactorEnabled {
+		twoFactorToken, err := auth.GeneratePurposeJWT(user.ID, auth.PurposeTwoFactorLogin, secret, 5*time.Minute)
 		if err != nil {
 			log.Println("POST [api/login] " + r.RemoteAddr + ": " + err.Error())
-		http.Error(w, "Could not generate token", http.StatusInternalServerError)
+			http.Error(w, "Could not generate 2FA challenge", http.StatusInternalServerError)
 			return
 		}
 
-	refreshTokenPlain, err := utils.GenerateRefreshToken()
-	if err != nil {
-		log.Println("POST [api/login] " + r.RemoteAddr + ": " + err.Error())
-		http.Error(w, "could not generate refresh token", http.StatusInternalServerError)
-		return
-	}
-	refreshHash := utils.HashToken(refreshTokenPlain)
-	refreshID := utils.GenerateUUID()
-	refreshExpires := time.Now().Add(7 * 24 * time.Hour).Unix() // expiry: 7 days
-
-	deviceInfo := r.Header.Get("User-Agent")
-
-	if err := storage.AddRefreshToken(&models.RefreshToken{
-		ID:         refreshID,
-		UserID:     user.ID,
-		Token:      refreshHash,
-		ExpiresAt:  refreshExpires,
-		DeviceInfo: deviceInfo,
-		CreatedAt:  time.Now().Unix(),
-		Revoked:    false,
-	}); err != nil {
-		log.Println("POST [api/login] " + r.RemoteAddr + ": " + err.Error())
-		http.Error(w, "could not save refresh token", http.StatusInternalServerError)
+		writeJSON(w, http.StatusOK, map[string]interface{}{
+			"requires_2fa":     true,
+			"two_factor_token": twoFactorToken,
+		})
+		log.Println("POST [api/login] " + r.RemoteAddr + ": Password accepted, 2FA required")
 		return
 	}
 
-	// Return access + refresh token (refresh in plain for client to store securely)
-	resp := map[string]interface{}{
-		"access_token":  accessToken,
-		"refresh_token": refreshTokenPlain,
-		"user": map[string]interface{}{
-			"id":       user.ID,
-			"username": user.Username,
-			"role":     user.Role,
-		},
-	}
-
-	w.Header().Set("Content-Type", "application/json")
-	err = json.NewEncoder(w).Encode(resp)
-	if err != nil {
-		log.Println("POST [api/login] " + r.RemoteAddr + ": " + err.Error())
-		http.Error(w, "Something went wrong", http.StatusInternalServerError)
-		return
-	}
+	issueLoginSession(w, r, user)
 	log.Println("POST [api/login] " + r.RemoteAddr + ": Successfully logged in")
 }
+
+func APILoginTwoFactor(w http.ResponseWriter, r *http.Request) {
+	var req struct {
+		TwoFactorToken string `json:"two_factor_token"`
+		Code           string `json:"code"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		log.Println("POST [api/login/2fa] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid request", http.StatusBadRequest)
+		return
+	}
+
+	secret := []byte(os.Getenv("JWT_SECRET"))
+	claims, err := auth.ValidatePurposeJWT(req.TwoFactorToken, auth.PurposeTwoFactorLogin, secret)
+	if err != nil {
+		log.Println("POST [api/login/2fa] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid or expired 2FA challenge", http.StatusUnauthorized)
+		return
+	}
+
+	user, err := storage.GetUserById(claims.UserID)
+	if err != nil || !user.TwoFactorEnabled || user.TwoFactorSecret == "" {
+		log.Println("POST [api/login/2fa] " + r.RemoteAddr + ": 2FA not available for user")
+		http.Error(w, "Invalid 2FA state", http.StatusUnauthorized)
+		return
+	}
+
+	code := strings.TrimSpace(req.Code)
+	validTOTP := totp.Validate(code, user.TwoFactorSecret)
+	usedRecoveryCode := false
+
+	if !validTOTP {
+		recoveryCodeHash := utils.HashToken(normalizeRecoveryCode(code))
+		usedRecoveryCode, err = storage.UseUserRecoveryCode(user.ID, recoveryCodeHash)
+		if err != nil {
+			log.Println("POST [api/login/2fa] " + r.RemoteAddr + ": " + err.Error())
+			http.Error(w, "Could not validate recovery code", http.StatusInternalServerError)
+			return
+		}
+	}
+
+	if !validTOTP && !usedRecoveryCode {
+		log.Println("POST [api/login/2fa] " + r.RemoteAddr + ": Invalid 2FA or recovery code")
+		http.Error(w, "Invalid 2FA or recovery code", http.StatusUnauthorized)
+		return
+	}
+
+	issueLoginSession(w, r, user)
+	if usedRecoveryCode {
+		log.Println("POST [api/login/2fa] " + r.RemoteAddr + ": Successfully logged in with recovery code")
+		return
+	}
+	log.Println("POST [api/login/2fa] " + r.RemoteAddr + ": Successfully logged in with 2FA")
+}
+
+func AccountUpdateUsername(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	var req struct {
+		Username string `json:"username"`
+		Password string `json:"password"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		log.Println("POST [api/account/username] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid request", http.StatusBadRequest)
+		return
+	}
+
+	username := strings.TrimSpace(req.Username)
+	if username == "" || req.Password == "" {
+		http.Error(w, "Username and password required", http.StatusBadRequest)
+		return
+	}
+
+	claims := r.Context().Value(auth.UserContextKey).(*auth.Claims)
+	user, err := storage.GetUserById(claims.UserID)
+	if err != nil {
+		log.Println("POST [api/account/username] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "User not found", http.StatusNotFound)
+		return
+	}
+
+	if !auth.CheckPasswordHash(req.Password, user.Password) {
+		http.Error(w, "Invalid password", http.StatusUnauthorized)
+		return
+	}
+
+	if err := storage.UpdateUserUsername(user.ID, username); err != nil {
+		log.Println("POST [api/account/username] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Username already exists or could not be saved", http.StatusConflict)
+		return
+	}
+
+	writeJSON(w, http.StatusOK, map[string]interface{}{
+		"username": strings.ToLower(username),
+	})
+	log.Println("POST [api/account/username] " + r.RemoteAddr + ": Updated username")
+}
+
+func AccountUpdatePassword(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	var req struct {
+		CurrentPassword string `json:"current_password"`
+		NewPassword     string `json:"new_password"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		log.Println("POST [api/account/password] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid request", http.StatusBadRequest)
+		return
+	}
+
+	if req.CurrentPassword == "" || req.NewPassword == "" {
+		http.Error(w, "Current and new password required", http.StatusBadRequest)
+		return
+	}
+	if len(req.NewPassword) > 72 {
+		http.Error(w, "Password exceeds the maximum allowed length of 72 characters", http.StatusUnprocessableEntity)
+		return
+	}
+	if req.CurrentPassword == req.NewPassword {
+		http.Error(w, "New password must be different", http.StatusBadRequest)
+		return
+	}
+
+	claims := r.Context().Value(auth.UserContextKey).(*auth.Claims)
+	user, err := storage.GetUserById(claims.UserID)
+	if err != nil {
+		log.Println("POST [api/account/password] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "User not found", http.StatusNotFound)
+		return
+	}
+
+	if !auth.CheckPasswordHash(req.CurrentPassword, user.Password) {
+		http.Error(w, "Invalid password", http.StatusUnauthorized)
+		return
+	}
+
+	hashed, err := auth.HashPassword(req.NewPassword)
+	if err != nil {
+		log.Println("POST [api/account/password] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not hash password", http.StatusInternalServerError)
+		return
+	}
+
+	if err := storage.UpdateUserPassword(user.ID, hashed); err != nil {
+		log.Println("POST [api/account/password] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not update password", http.StatusInternalServerError)
+		return
+	}
+
+	if err := storage.RevokeAllRefreshTokensForUser(user.ID); err != nil {
+		log.Println("POST [api/account/password] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not revoke old sessions", http.StatusInternalServerError)
+		return
+	}
+
+	user.Password = hashed
+	issueLoginSession(w, r, user)
+	log.Println("POST [api/account/password] " + r.RemoteAddr + ": Updated password")
+}
+
+func TwoFactorSetup(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	claims := r.Context().Value(auth.UserContextKey).(*auth.Claims)
+	user, err := storage.GetUserById(claims.UserID)
+	if err != nil {
+		log.Println("POST [api/2fa/setup] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "User not found", http.StatusNotFound)
+		return
+	}
+
+	if user.TwoFactorEnabled {
+		http.Error(w, "2FA is already enabled", http.StatusConflict)
+		return
+	}
+
+	key, err := totp.Generate(totp.GenerateOpts{
+		Issuer:      "MiauInv",
+		AccountName: user.Username,
+		SecretSize:  20,
+	})
+	if err != nil {
+		log.Println("POST [api/2fa/setup] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not generate 2FA secret", http.StatusInternalServerError)
+		return
+	}
+
+	secret := []byte(os.Getenv("JWT_SECRET"))
+	if len(secret) == 0 {
+		log.Println("POST [api/2fa/setup] " + r.RemoteAddr + ": Server misconfiguration")
+		http.Error(w, "Server misconfiguration", http.StatusInternalServerError)
+		return
+	}
+
+	setupToken, err := auth.GenerateTwoFactorSetupJWT(user.ID, key.Secret(), secret, 10*time.Minute)
+	if err != nil {
+		log.Println("POST [api/2fa/setup] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not create 2FA setup challenge", http.StatusInternalServerError)
+		return
+	}
+
+	img, err := key.Image(220, 220)
+	if err != nil {
+		log.Println("POST [api/2fa/setup] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not generate QR code", http.StatusInternalServerError)
+		return
+	}
+
+	var qr bytes.Buffer
+	if err := png.Encode(&qr, img); err != nil {
+		log.Println("POST [api/2fa/setup] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not encode QR code", http.StatusInternalServerError)
+		return
+	}
+
+	writeJSON(w, http.StatusOK, map[string]interface{}{
+		"secret":      key.Secret(),
+		"setup_token": setupToken,
+		"otpauth_url": key.URL(),
+		"qr_code":     "data:image/png;base64," + base64.StdEncoding.EncodeToString(qr.Bytes()),
+	})
+	log.Println("POST [api/2fa/setup] " + r.RemoteAddr + ": Created 2FA setup challenge")
+}
+
+func TwoFactorEnable(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	var req struct {
+		Code       string `json:"code"`
+		SetupToken string `json:"setup_token"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		log.Println("POST [api/2fa/enable] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid request", http.StatusBadRequest)
+		return
+	}
+
+	claims := r.Context().Value(auth.UserContextKey).(*auth.Claims)
+	user, err := storage.GetUserById(claims.UserID)
+	if err != nil {
+		log.Println("POST [api/2fa/enable] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "User not found", http.StatusNotFound)
+		return
+	}
+
+	setupSecret := ""
+	secret := []byte(os.Getenv("JWT_SECRET"))
+	if req.SetupToken != "" {
+		setupClaims, err := auth.ValidateTwoFactorSetupJWT(req.SetupToken, secret)
+		if err != nil {
+			log.Println("POST [api/2fa/enable] " + r.RemoteAddr + ": " + err.Error())
+			http.Error(w, "Invalid or expired 2FA setup challenge", http.StatusUnauthorized)
+			return
+		}
+		if setupClaims.UserID != user.ID {
+			http.Error(w, "Invalid 2FA setup challenge", http.StatusUnauthorized)
+			return
+		}
+		setupSecret = setupClaims.Secret
+	} else if !user.TwoFactorEnabled && user.TwoFactorSecret != "" {
+		// Compatibility for accounts that started setup before temporary setup tokens existed.
+		setupSecret = user.TwoFactorSecret
+	}
+
+	if setupSecret == "" {
+		http.Error(w, "2FA setup has not been started", http.StatusBadRequest)
+		return
+	}
+
+	if !totp.Validate(strings.TrimSpace(req.Code), setupSecret) {
+		http.Error(w, "Invalid 2FA code", http.StatusUnauthorized)
+		return
+	}
+
+	recoveryCodes, recoveryCodeHashes, err := generateRecoveryCodes(10)
+	if err != nil {
+		log.Println("POST [api/2fa/enable] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not generate recovery codes", http.StatusInternalServerError)
+		return
+	}
+
+	if err := storage.EnableUserTwoFactorWithSecretAndRecoveryCodes(user.ID, setupSecret, recoveryCodeHashes); err != nil {
+		log.Println("POST [api/2fa/enable] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not enable 2FA", http.StatusInternalServerError)
+		return
+	}
+
+	if err := storage.RevokeAllRefreshTokensForUser(user.ID); err != nil {
+		log.Println("POST [api/2fa/enable] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not revoke old sessions", http.StatusInternalServerError)
+		return
+	}
+
+	user.TwoFactorEnabled = true
+	user.TwoFactorSecret = setupSecret
+	issueLoginSessionWithExtra(w, r, user, map[string]interface{}{
+		"two_factor_enabled":        true,
+		"recovery_codes":            recoveryCodes,
+		"recovery_codes_remaining":  len(recoveryCodes),
+		"recovery_codes_warning":    false,
+		"recovery_codes_warning_at": recoveryCodeWarningThreshold,
+	})
+	log.Println("POST [api/2fa/enable] " + r.RemoteAddr + ": Enabled 2FA, replaced recovery codes, and revoked old sessions")
+}
+
+func TwoFactorDisable(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	var req struct {
+		Password string `json:"password"`
+		Code     string `json:"code"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		log.Println("POST [api/2fa/disable] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid request", http.StatusBadRequest)
+		return
+	}
+
+	claims := r.Context().Value(auth.UserContextKey).(*auth.Claims)
+	user, err := storage.GetUserById(claims.UserID)
+	if err != nil {
+		log.Println("POST [api/2fa/disable] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "User not found", http.StatusNotFound)
+		return
+	}
+
+	if !auth.CheckPasswordHash(req.Password, user.Password) {
+		http.Error(w, "Invalid password", http.StatusUnauthorized)
+		return
+	}
+
+	if user.TwoFactorEnabled && !totp.Validate(strings.TrimSpace(req.Code), user.TwoFactorSecret) {
+		http.Error(w, "Invalid 2FA code", http.StatusUnauthorized)
+		return
+	}
+
+	if err := storage.DisableUserTwoFactor(user.ID); err != nil {
+		log.Println("POST [api/2fa/disable] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not disable 2FA", http.StatusInternalServerError)
+		return
+	}
+
+	if err := storage.RevokeAllRefreshTokensForUser(user.ID); err != nil {
+		log.Println("POST [api/2fa/disable] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not revoke sessions", http.StatusInternalServerError)
+		return
+	}
+
+	clearAuthCookies(w)
+	writeJSON(w, http.StatusOK, map[string]interface{}{"two_factor_enabled": false})
+	log.Println("POST [api/2fa/disable] " + r.RemoteAddr + ": Disabled 2FA")
+}
+
+func TwoFactorRegenerateRecoveryCodes(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	var req struct {
+		Password string `json:"password"`
+		Code     string `json:"code"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		log.Println("POST [api/2fa/recovery-codes/regenerate] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid request", http.StatusBadRequest)
+		return
+	}
+
+	claims := r.Context().Value(auth.UserContextKey).(*auth.Claims)
+	user, err := storage.GetUserById(claims.UserID)
+	if err != nil {
+		log.Println("POST [api/2fa/recovery-codes/regenerate] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "User not found", http.StatusNotFound)
+		return
+	}
+
+	if !user.TwoFactorEnabled || user.TwoFactorSecret == "" {
+		http.Error(w, "2FA is not enabled", http.StatusBadRequest)
+		return
+	}
+
+	if !auth.CheckPasswordHash(req.Password, user.Password) {
+		http.Error(w, "Invalid password", http.StatusUnauthorized)
+		return
+	}
+
+	if !totp.Validate(strings.TrimSpace(req.Code), user.TwoFactorSecret) {
+		http.Error(w, "Invalid 2FA code", http.StatusUnauthorized)
+		return
+	}
+
+	recoveryCodes, recoveryCodeHashes, err := generateRecoveryCodes(10)
+	if err != nil {
+		log.Println("POST [api/2fa/recovery-codes/regenerate] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not generate recovery codes", http.StatusInternalServerError)
+		return
+	}
+
+	if err := storage.ReplaceUserRecoveryCodes(user.ID, recoveryCodeHashes); err != nil {
+		log.Println("POST [api/2fa/recovery-codes/regenerate] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not save recovery codes", http.StatusInternalServerError)
+		return
+	}
+
+	writeJSON(w, http.StatusOK, map[string]interface{}{
+		"recovery_codes": recoveryCodes,
+	})
+	log.Println("POST [api/2fa/recovery-codes/regenerate] " + r.RemoteAddr + ": Regenerated recovery codes")
+}
+
 func Logout(w http.ResponseWriter, r *http.Request) {
 	claims := r.Context().Value(auth.UserContextKey).(*auth.Claims)
 	err := storage.RevokeAllRefreshTokensForUser(claims.UserID)
@@ -140,8 +548,10 @@ func Logout(w http.ResponseWriter, r *http.Request) {
 		http.Error(w, "Internal server error", http.StatusInternalServerError)
 		return
 	}
-	w.WriteHeader(204)
+	clearAuthCookies(w)
+	w.WriteHeader(http.StatusNoContent)
 }
+
 func TestHandler(w http.ResponseWriter, r *http.Request) {
 	claims, _ := utils.IsLoggedIn(w, r)
 
@@ -155,15 +565,26 @@ func TestHandler(w http.ResponseWriter, r *http.Request) {
 		log.Println("GET [api/ping] " + r.RemoteAddr + ": " + err.Error())
 		return
 	}
-	log.Println("GET [api/login] " + r.RemoteAddr + ": Successfully tested connection")
+	log.Println("GET [api/ping] " + r.RemoteAddr + ": Successfully tested connection")
 }
+
 func RefreshToken(w http.ResponseWriter, r *http.Request) {
 	var req struct {
 		RefreshToken string `json:"refresh_token"`
 	}
-	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
-		log.Println("POST [api/refresh] " + r.RemoteAddr + ": " + err.Error())
-		http.Error(w, "Invalid request", http.StatusBadRequest)
+
+	if r.Body != nil {
+		_ = json.NewDecoder(r.Body).Decode(&req)
+	}
+	if req.RefreshToken == "" {
+		cookie, err := r.Cookie("refresh_token")
+		if err == nil {
+			req.RefreshToken = cookie.Value
+		}
+	}
+	if req.RefreshToken == "" {
+		log.Println("POST [api/refresh] " + r.RemoteAddr + ": Missing refresh token")
+		http.Error(w, "Invalid refresh token", http.StatusUnauthorized)
 		return
 	}
 
@@ -180,43 +601,17 @@ func RefreshToken(w http.ResponseWriter, r *http.Request) {
 		log.Println(err)
 	}
 
-	newToken, _ := utils.GenerateRefreshToken()
-	newHash := utils.HashToken(newToken)
-	newExpires := time.Now().Add(7 * 24 * time.Hour).Unix() //7 days
-	newID := utils.GenerateUUID()
-	deviceInfo := r.Header.Get("User-Agent")
-	if err = storage.AddRefreshToken(&models.RefreshToken{
-		ID:         newID,
-		UserID:     tokenRow.UserID,
-		Token:      newHash,
-		ExpiresAt:  newExpires,
-		CreatedAt:  time.Now().Unix(),
-		Revoked:    false,
-		DeviceInfo: deviceInfo,
-	}); err != nil {
-		log.Println("POST [api/refresh] " + r.RemoteAddr + ": " + err.Error())
-		http.Error(w, "Could not generate new refresh token", http.StatusInternalServerError)
-		return
-	}
-
 	user, err := storage.GetUserById(tokenRow.UserID)
 	if err != nil {
 		log.Println("POST [api/refresh] " + r.RemoteAddr + ": " + err.Error())
 		http.Error(w, "Internal server error", http.StatusInternalServerError)
 		return
 	}
-	accessToken, _ := auth.GenerateJWT(tokenRow.UserID, user.Role, []byte(os.Getenv("JWT_SECRET")))
 
-	if err = json.NewEncoder(w).Encode(map[string]string{
-		"access_token":  accessToken,
-		"refresh_token": newToken,
-	}); err != nil {
-		log.Println("POST [api/refresh] " + r.RemoteAddr + ": " + err.Error())
-		http.Error(w, "Internal server error", http.StatusInternalServerError)
-		return
-	}
+	issueLoginSession(w, r, user)
 	log.Println("POST [api/refresh] " + r.RemoteAddr + ": Successfully refreshed token")
 }
+
 func UserInfo(w http.ResponseWriter, r *http.Request) {
 	if r.Method != http.MethodGet {
 		log.Println("GET [api/userinfo] " + r.RemoteAddr + ": Method " + r.Method + " not allowed")
@@ -225,21 +620,228 @@ func UserInfo(w http.ResponseWriter, r *http.Request) {
 	}
 	query := r.URL.Query()
 	idParam := query.Get("id")
+
+	if idParam == "" {
+		tokenStr := ""
+		authHeader := r.Header.Get("Authorization")
+
+		if strings.HasPrefix(authHeader, "Bearer ") {
+			tokenStr = strings.TrimPrefix(authHeader, "Bearer ")
+		}
+
+		if tokenStr == "" {
+			cookie, err := r.Cookie("access_token")
+			if err == nil {
+				tokenStr = cookie.Value
+			}
+		}
+
+		if tokenStr == "" {
+			http.Error(w, "Missing token", http.StatusUnauthorized)
+			return
+		}
+
+		claims, err := auth.ValidateJWT(tokenStr, models.JWTSecret)
+
+		if err != nil {
+			log.Println("GET [api/userinfo] " + r.RemoteAddr + ": " + err.Error())
+			http.Error(w, "Unauthorized: Invalid or expired token", http.StatusUnauthorized)
+			return
+		}
+
+		idParam = claims.UserID
+	}
+
 	user, err := storage.GetUserById(idParam)
 	if err != nil {
 		log.Println("GET [api/userinfo] " + r.RemoteAddr + ": User " + idParam + " not found")
 		http.Error(w, "User not found", http.StatusNotFound)
 		return
 	}
+
+	recoveryCodesRemaining := 0
+	if user.TwoFactorEnabled {
+		if count, err := storage.CountUnusedRecoveryCodes(user.ID); err == nil {
+			recoveryCodesRemaining = count
+		}
+	}
+	twoFactorStatus := "disabled"
+	if user.TwoFactorEnabled {
+		twoFactorStatus = "enabled"
+	} else if user.TwoFactorSecret != "" {
+		twoFactorStatus = "setup_pending"
+	}
+	recoveryCodesWarning := user.TwoFactorEnabled && recoveryCodesRemaining <= recoveryCodeWarningThreshold
+	passkeyCount := 0
+	if count, err := storage.CountPasskeyCredentials(user.ID); err == nil {
+		passkeyCount = count
+	}
+
 	w.Header().Set("Content-Type", "application/json")
 	err = json.NewEncoder(w).Encode(map[string]interface{}{
 		"id":                        user.ID,
-		"name":       user.Username,
+		"username":                  user.Username,
 		"avatar_url":                "",
+		"two_factor_enabled":        user.TwoFactorEnabled,
+		"two_factor_status":         twoFactorStatus,
+		"recovery_codes_remaining":  recoveryCodesRemaining,
+		"recovery_codes_warning":    recoveryCodesWarning,
+		"recovery_codes_warning_at": recoveryCodeWarningThreshold,
+		"passkeys_enabled":          passkeyCount > 0,
+		"passkey_count":             passkeyCount,
 	})
 	if err != nil {
 		log.Println("GET [api/userinfo] " + r.RemoteAddr + ": " + err.Error())
 		return
 	}
-	log.Println("GET [api/userinfo] " + r.RemoteAddr + ": Successfully retrieved user info")
+	log.Println("GET [api/userinfo] " + r.RemoteAddr + ": Successfully retrieved user info of " + user.Username + " (" + user.ID + ")")
+}
+
+func issueLoginSession(w http.ResponseWriter, r *http.Request, user models.User) {
+	issueLoginSessionWithExtra(w, r, user, nil)
+}
+
+func issueLoginSessionWithExtra(w http.ResponseWriter, r *http.Request, user models.User, extra map[string]interface{}) {
+	secret := []byte(os.Getenv("JWT_SECRET"))
+	if len(secret) == 0 {
+		log.Println("AUTH " + r.RemoteAddr + ": Server misconfiguration")
+		http.Error(w, "Server misconfiguration", http.StatusInternalServerError)
+		return
+	}
+
+	accessToken, err := auth.GenerateJWT(user.ID, user.Role, secret)
+	if err != nil {
+		log.Println("AUTH " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not generate token", http.StatusInternalServerError)
+		return
+	}
+
+	refreshTokenPlain, err := utils.GenerateRefreshToken()
+	if err != nil {
+		log.Println("AUTH " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "could not generate refresh token", http.StatusInternalServerError)
+		return
+	}
+
+	refreshExpires := time.Now().Add(7 * 24 * time.Hour).Unix()
+	if err := storage.AddRefreshToken(&models.RefreshToken{
+		ID:         utils.GenerateUUID(),
+		UserID:     user.ID,
+		Token:      utils.HashToken(refreshTokenPlain),
+		ExpiresAt:  refreshExpires,
+		DeviceInfo: r.Header.Get("User-Agent"),
+		CreatedAt:  time.Now().Unix(),
+		Revoked:    false,
+	}); err != nil {
+		log.Println("AUTH " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "could not save refresh token", http.StatusInternalServerError)
+		return
+	}
+
+	passkeyCount := 0
+	if count, err := storage.CountPasskeyCredentials(user.ID); err == nil {
+		passkeyCount = count
+	}
+
+	setAuthCookies(w, accessToken, refreshTokenPlain)
+	response := map[string]interface{}{
+		"access_token":  accessToken,
+		"refresh_token": refreshTokenPlain,
+		"user": map[string]interface{}{
+			"id":                 user.ID,
+			"username":           user.Username,
+			"role":               user.Role,
+			"two_factor_enabled": user.TwoFactorEnabled,
+			"passkeys_enabled":   passkeyCount > 0,
+			"passkey_count":      passkeyCount,
+		},
+	}
+	for key, value := range extra {
+		response[key] = value
+	}
+	writeJSON(w, http.StatusOK, response)
+}
+
+func generateRecoveryCodes(count int) ([]string, []string, error) {
+	codes := make([]string, 0, count)
+	hashes := make([]string, 0, count)
+	seen := make(map[string]struct{}, count)
+
+	for len(codes) < count {
+		code, err := generateRecoveryCode()
+		if err != nil {
+			return nil, nil, err
+		}
+
+		normalized := normalizeRecoveryCode(code)
+		if _, exists := seen[normalized]; exists {
+			continue
+		}
+		seen[normalized] = struct{}{}
+
+		codes = append(codes, code)
+		hashes = append(hashes, utils.HashToken(normalized))
+	}
+
+	return codes, hashes, nil
+}
+
+func generateRecoveryCode() (string, error) {
+	bytes := make([]byte, 10)
+	if _, err := rand.Read(bytes); err != nil {
+		return "", err
+	}
+
+	raw := hex.EncodeToString(bytes)
+	return raw[0:5] + "-" + raw[5:10] + "-" + raw[10:15] + "-" + raw[15:20], nil
+}
+
+func normalizeRecoveryCode(code string) string {
+	code = strings.TrimSpace(code)
+	code = strings.ReplaceAll(code, "-", "")
+	code = strings.ReplaceAll(code, " ", "")
+	return strings.ToLower(code)
+}
+
+func setAuthCookies(w http.ResponseWriter, accessToken, refreshToken string) {
+	http.SetCookie(w, &http.Cookie{
+		Name:     "access_token",
+		Value:    accessToken,
+		Path:     "/",
+		MaxAge:   15 * 60,
+		HttpOnly: true,
+		Secure:   true,
+		SameSite: http.SameSiteLaxMode,
+	})
+	http.SetCookie(w, &http.Cookie{
+		Name:     "refresh_token",
+		Value:    refreshToken,
+		Path:     "/",
+		MaxAge:   7 * 24 * 60 * 60,
+		HttpOnly: true,
+		Secure:   true,
+		SameSite: http.SameSiteLaxMode,
+	})
+}
+
+func clearAuthCookies(w http.ResponseWriter) {
+	for _, name := range []string{"access_token", "refresh_token"} {
+		http.SetCookie(w, &http.Cookie{
+			Name:     name,
+			Value:    "",
+			Path:     "/",
+			MaxAge:   -1,
+			HttpOnly: true,
+			Secure:   true,
+			SameSite: http.SameSiteLaxMode,
+		})
+	}
+}
+
+func writeJSON(w http.ResponseWriter, status int, data interface{}) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(status)
+	if err := json.NewEncoder(w).Encode(data); err != nil {
+		log.Println("JSON response error: " + err.Error())
+	}
 }

handlers/api.go

@@ -0,0 +1,676 @@
+package handlers
+
+import (
+	"MiauInv/models"
+	"MiauInv/storage"
+	"database/sql"
+	"encoding/json"
+	"log"
+	"net/http"
+	"strconv"
+	"strings"
+)
+
+func Location(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+
+	switch r.Method {
+
+	case http.MethodGet:
+		idStr := r.URL.Query().Get("id")
+		contentMode := r.URL.Query().Get("content")
+
+		if idStr != "" && contentMode == "true" {
+			locationID, err := strconv.Atoi(idStr)
+			if err != nil {
+				http.Error(w, "Invalid location ID", http.StatusBadRequest)
+				return
+			}
+
+			query := `
+				SELECT s.item_id, i.name, s.quantity 
+				FROM stock s
+				JOIN items i ON s.item_id = i.id
+				WHERE s.location_id = ? AND s.quantity > 0
+			`
+
+			rows, err := storage.DB.Query(query, locationID)
+			if err != nil {
+				http.Error(w, "Database error", http.StatusInternalServerError)
+				return
+			}
+			defer rows.Close()
+
+			var contents []models.LocationContent
+			for rows.Next() {
+				var c models.LocationContent
+				if err := rows.Scan(&c.ItemID, &c.ItemName, &c.Quantity); err != nil {
+					http.Error(w, "Row scan error", http.StatusInternalServerError)
+					return
+				}
+				contents = append(contents, c)
+			}
+
+			json.NewEncoder(w).Encode(map[string]interface{}{"contents": contents})
+			return
+		}
+
+		if idStr != "" {
+			id, err := strconv.Atoi(idStr)
+			if err != nil {
+				http.Error(w, "Invalid ID parameter", http.StatusBadRequest)
+				return
+			}
+
+			var loc models.Location
+			err = storage.DB.QueryRow("SELECT id, name FROM locations WHERE id = ?", id).Scan(&loc.ID, &loc.Name)
+			if err != nil {
+				if err == sql.ErrNoRows {
+					log.Println("GET [api/locations] " + r.RemoteAddr + ": Location not found (ID " + idStr + ")")
+					http.Error(w, "Location not found", http.StatusNotFound)
+					return
+				}
+				log.Println("GET [api/locations] DB Error: " + err.Error())
+				http.Error(w, "Internal server error", http.StatusInternalServerError)
+				return
+			}
+
+			json.NewEncoder(w).Encode(loc)
+			log.Println("GET [api/locations] " + r.RemoteAddr + ": Successfully retrieved location ID " + idStr)
+			return
+		}
+
+		rows, err := storage.DB.Query("SELECT id, name FROM locations ORDER BY name ASC")
+		if err != nil {
+			log.Println("GET [api/locations] " + r.RemoteAddr + ": " + err.Error())
+			http.Error(w, "Internal server error", http.StatusInternalServerError)
+			return
+		}
+		defer rows.Close()
+
+		var locations []models.Location
+		for rows.Next() {
+			var loc models.Location
+			if err := rows.Scan(&loc.ID, &loc.Name); err != nil {
+				log.Println("GET [api/locations] Scan Error: " + err.Error())
+				continue
+			}
+			locations = append(locations, loc)
+		}
+
+		if locations == nil {
+			locations = []models.Location{}
+		}
+
+		json.NewEncoder(w).Encode(map[string]interface{}{
+			"locations": locations,
+		})
+		log.Println("GET [api/locations] " + r.RemoteAddr + ": Successfully retrieved all locations")
+
+	case http.MethodPost:
+		var body struct {
+			Name string `json:"name"`
+		}
+
+		if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
+			log.Println("POST [api/locations] Decode Error: " + err.Error())
+			http.Error(w, "Invalid request body", http.StatusBadRequest)
+			return
+		}
+
+		if strings.TrimSpace(body.Name) == "" {
+			http.Error(w, "Location name cannot be empty", http.StatusBadRequest)
+			return
+		}
+
+		res, err := storage.DB.Exec("INSERT INTO locations(name) VALUES(?)", body.Name)
+		if err != nil {
+			log.Println("POST [api/locations] DB Error: " + err.Error())
+			http.Error(w, "Location already exists or database error", http.StatusConflict)
+			return
+		}
+
+		lastID, _ := res.LastInsertId()
+
+		w.WriteHeader(http.StatusCreated)
+		json.NewEncoder(w).Encode(models.Location{
+			ID:   int(lastID),
+			Name: body.Name,
+		})
+		log.Println("POST [api/locations] " + r.RemoteAddr + ": Successfully created location " + body.Name)
+
+	case http.MethodPut:
+		idStr := r.URL.Query().Get("id")
+		if idStr == "" {
+			http.Error(w, "Missing ID parameter for update", http.StatusBadRequest)
+			return
+		}
+
+		id, err := strconv.Atoi(idStr)
+		if err != nil {
+			http.Error(w, "Invalid ID parameter", http.StatusBadRequest)
+			return
+		}
+
+		var body struct {
+			Name string `json:"name"`
+		}
+
+		if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
+			log.Println("PUT [api/locations] Decode Error: " + err.Error())
+			http.Error(w, "Invalid request body", http.StatusBadRequest)
+			return
+		}
+
+		if strings.TrimSpace(body.Name) == "" {
+			http.Error(w, "Location name cannot be empty", http.StatusBadRequest)
+			return
+		}
+
+		res, err := storage.DB.Exec("UPDATE locations SET name = ? WHERE id = ?", body.Name, id)
+		if err != nil {
+			log.Println("PUT [api/locations] DB Error: " + err.Error())
+			http.Error(w, "Location name unique constraint failed or database error", http.StatusConflict)
+			return
+		}
+
+		rowsAffected, _ := res.RowsAffected()
+		if rowsAffected == 0 {
+			http.Error(w, "Location not found", http.StatusNotFound)
+			return
+		}
+
+		json.NewEncoder(w).Encode(models.Location{
+			ID:   id,
+			Name: body.Name,
+		})
+		log.Println("PUT [api/locations] " + r.RemoteAddr + ": Successfully updated location ID " + idStr)
+
+	case http.MethodDelete:
+		idStr := r.URL.Query().Get("id")
+		if idStr == "" {
+			http.Error(w, "Missing ID parameter for deletion", http.StatusBadRequest)
+			return
+		}
+
+		id, err := strconv.Atoi(idStr)
+		if err != nil {
+			http.Error(w, "Invalid ID parameter", http.StatusBadRequest)
+			return
+		}
+
+		res, err := storage.DB.Exec("DELETE FROM locations WHERE id = ?", id)
+		if err != nil {
+			log.Println("DELETE [api/locations] DB Error: " + err.Error())
+			http.Error(w, "Cannot delete location. It might still be in use by inventory stock.", http.StatusConflict)
+			return
+		}
+
+		rowsAffected, _ := res.RowsAffected()
+		if rowsAffected == 0 {
+			http.Error(w, "Location not found", http.StatusNotFound)
+			return
+		}
+
+		w.WriteHeader(http.StatusNoContent)
+		log.Println("DELETE [api/locations] " + r.RemoteAddr + ": Successfully deleted location ID " + idStr)
+
+	default:
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+	}
+}
+func Item(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+
+	switch r.Method {
+	case http.MethodGet:
+
+		idStr := r.URL.Query().Get("id")
+
+		if idStr != "" {
+			id, err := strconv.Atoi(idStr)
+			if err != nil {
+				http.Error(w, "Invalid ID parameter", http.StatusBadRequest)
+				return
+			}
+
+			var item models.Item
+			err = storage.DB.QueryRow("SELECT id, name, category, description, total_quantity FROM items WHERE id = ?", id).Scan(&item.ID, &item.Name, &item.Category, &item.Description, &item.TotalQuantity)
+			if err != nil {
+				if err == sql.ErrNoRows {
+					log.Println("GET [api/locations] " + r.RemoteAddr + ": Location not found (ID " + idStr + ")")
+					http.Error(w, "Location not found", http.StatusNotFound)
+					return
+				}
+				log.Println("GET [api/item] DB Error: " + err.Error())
+				http.Error(w, "Internal server error", http.StatusInternalServerError)
+				return
+			}
+
+			json.NewEncoder(w).Encode(item)
+			log.Println("GET [api/item] " + r.RemoteAddr + ": Successfully retrieved item ID " + idStr)
+			return
+		}
+
+		query := `
+		SELECT 
+			i.id, i.name, i.category, i.description,
+			COALESCE((SELECT SUM(quantity) FROM stock WHERE item_id = i.id), 0) as total_qty,
+			COALESCE((SELECT SUM(quantity) FROM project_items WHERE item_id = i.id), 0) as allocated_qty
+		FROM items i
+		ORDER BY i.name ASC
+	`
+		rows, err := storage.DB.Query(query)
+		if err != nil {
+			http.Error(w, "Database error", http.StatusInternalServerError)
+			return
+		}
+		defer rows.Close()
+
+		var itemsExtended []models.ItemExtended
+		for rows.Next() {
+			var ie models.ItemExtended
+			err := rows.Scan(&ie.ID, &ie.Name, &ie.Category, &ie.Description, &ie.TotalQuantity, &ie.AllocatedQty)
+			if err != nil {
+				continue
+			}
+			ie.AvailableQty = ie.TotalQuantity - ie.AllocatedQty
+			itemsExtended = append(itemsExtended, ie)
+		}
+		json.NewEncoder(w).Encode(map[string]interface{}{"items": itemsExtended})
+		return
+
+	case http.MethodPost:
+		var body models.Item
+		if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
+			http.Error(w, "Invalid request body", http.StatusBadRequest)
+			return
+		}
+
+		res, err := storage.DB.Exec("INSERT INTO items(name, category, description, total_quantity) VALUES(?, ?, ?, ?)",
+			body.Name, body.Category, body.Description, body.TotalQuantity)
+		if err != nil {
+			http.Error(w, "Database error", http.StatusInternalServerError)
+			return
+		}
+
+		lastID, _ := res.LastInsertId()
+		body.ID = int(lastID)
+		w.WriteHeader(http.StatusCreated)
+		json.NewEncoder(w).Encode(body)
+
+	case http.MethodPut:
+		idStr := r.URL.Query().Get("id")
+		if idStr == "" {
+			http.Error(w, "Missing ID parameter", http.StatusBadRequest)
+			return
+		}
+		id, _ := strconv.Atoi(idStr)
+
+		var body models.Item
+		json.NewDecoder(r.Body).Decode(&body)
+
+		res, err := storage.DB.Exec("UPDATE items SET name = ?, category = ?, description = ?, total_quantity = ? WHERE id = ?",
+			body.Name, body.Category, body.Description, body.TotalQuantity, id)
+		if err != nil {
+			http.Error(w, "Database error", http.StatusInternalServerError)
+			return
+		}
+
+		rowsAffected, _ := res.RowsAffected()
+		if rowsAffected == 0 {
+			http.Error(w, "Item not found", http.StatusNotFound)
+			return
+		}
+
+		body.ID = id
+		json.NewEncoder(w).Encode(body)
+
+	case http.MethodDelete:
+		idStr := r.URL.Query().Get("id")
+		id, _ := strconv.Atoi(idStr)
+
+		// SQLite blockiert dank FK, falls Item noch im Stock oder Projekten ist
+		res, err := storage.DB.Exec("DELETE FROM items WHERE id = ?", id)
+		if err != nil {
+			http.Error(w, "Cannot delete item. Still referenced in stock or projects.", http.StatusConflict)
+			return
+		}
+
+		rowsAffected, _ := res.RowsAffected()
+		if rowsAffected == 0 {
+			http.Error(w, "Item not found", http.StatusNotFound)
+			return
+		}
+		w.WriteHeader(http.StatusNoContent)
+
+	default:
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+	}
+}
+func Project(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+
+	switch r.Method {
+	case http.MethodGet:
+		idStr := r.URL.Query().Get("id")
+
+		detailsMode := r.URL.Query().Get("details")
+
+		if idStr != "" && detailsMode == "true" {
+			projectID, err := strconv.Atoi(idStr)
+			if err != nil {
+				http.Error(w, "Invalid project ID", http.StatusBadRequest)
+				return
+			}
+
+			query := `
+				SELECT pi.item_id, i.name, pi.quantity 
+				FROM project_items pi
+				JOIN items i ON pi.item_id = i.id
+				WHERE pi.project_id = ?
+			`
+
+			rows, err := storage.DB.Query(query, projectID)
+			if err != nil {
+				http.Error(w, "Database error", http.StatusInternalServerError)
+				return
+			}
+			defer rows.Close()
+
+			var details []models.ProjectDetailItem
+			for rows.Next() {
+				var d models.ProjectDetailItem
+				if err := rows.Scan(&d.ItemID, &d.ItemName, &d.Quantity); err != nil {
+					http.Error(w, "Row scan error", http.StatusInternalServerError)
+					return
+				}
+				details = append(details, d)
+			}
+
+			json.NewEncoder(w).Encode(map[string]interface{}{"items": details})
+			return
+		}
+
+		if idStr != "" {
+			id, _ := strconv.Atoi(idStr)
+			var p models.Project
+			err := storage.DB.QueryRow("SELECT id, name, description FROM projects WHERE id = ?", id).Scan(&p.ID, &p.Name, &p.Description)
+			if err == sql.ErrNoRows {
+				http.Error(w, "Project not found", http.StatusNotFound)
+				return
+			}
+			json.NewEncoder(w).Encode(p)
+			return
+		}
+
+		rows, err := storage.DB.Query("SELECT id, name, description FROM projects ORDER BY name ASC")
+		if err != nil {
+			http.Error(w, "Internal server error", http.StatusInternalServerError)
+			return
+		}
+		defer rows.Close()
+
+		projects := []models.Project{}
+		for rows.Next() {
+			var p models.Project
+			rows.Scan(&p.ID, &p.Name, &p.Description)
+			projects = append(projects, p)
+		}
+		json.NewEncoder(w).Encode(map[string]interface{}{"projects": projects})
+
+	case http.MethodPost:
+		var body models.Project
+		json.NewDecoder(r.Body).Decode(&body)
+
+		res, err := storage.DB.Exec("INSERT INTO projects(name, description) VALUES(?, ?)", body.Name, body.Description)
+		if err != nil {
+			http.Error(w, "Project name already exists", http.StatusConflict)
+			return
+		}
+
+		lastID, _ := res.LastInsertId()
+		body.ID = int(lastID)
+		w.WriteHeader(http.StatusCreated)
+		json.NewEncoder(w).Encode(body)
+
+	case http.MethodPut:
+		idStr := r.URL.Query().Get("id")
+		id, _ := strconv.Atoi(idStr)
+
+		var body models.Project
+		json.NewDecoder(r.Body).Decode(&body)
+
+		res, err := storage.DB.Exec("UPDATE projects SET name = ?, description = ? WHERE id = ?", body.Name, body.Description, id)
+		if err != nil {
+			http.Error(w, "Project name constraint violation", http.StatusConflict)
+			return
+		}
+
+		rowsAffected, _ := res.RowsAffected()
+		if rowsAffected == 0 {
+			http.Error(w, "Project not found", http.StatusNotFound)
+			return
+		}
+		body.ID = id
+		json.NewEncoder(w).Encode(body)
+
+	case http.MethodDelete:
+		idStr := r.URL.Query().Get("id")
+		id, _ := strconv.Atoi(idStr)
+
+		res, err := storage.DB.Exec("DELETE FROM projects WHERE id = ?", id)
+		if err != nil {
+			http.Error(w, "Cannot delete project. Clear active item assignments first.", http.StatusConflict)
+			return
+		}
+
+		rowsAffected, _ := res.RowsAffected()
+		if rowsAffected == 0 {
+			http.Error(w, "Project not found", http.StatusNotFound)
+			return
+		}
+		w.WriteHeader(http.StatusNoContent)
+
+	default:
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+	}
+}
+func Stock(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+
+	switch r.Method {
+	case http.MethodGet:
+		idStr := r.URL.Query().Get("id")
+
+		if idStr != "" {
+			id, _ := strconv.Atoi(idStr)
+			var s models.Stock
+			err := storage.DB.QueryRow("SELECT id, item_id, location_id, quantity FROM stock WHERE id = ?", id).
+				Scan(&s.ID, &s.ItemID, &s.LocationID, &s.Quantity)
+			if err == sql.ErrNoRows {
+				http.Error(w, "Stock entry not found", http.StatusNotFound)
+				return
+			}
+			json.NewEncoder(w).Encode(s)
+			return
+		}
+
+		rows, err := storage.DB.Query("SELECT id, item_id, location_id, quantity FROM stock")
+		if err != nil {
+			http.Error(w, "Internal server error", http.StatusInternalServerError)
+			return
+		}
+		defer rows.Close()
+
+		stocks := []models.Stock{}
+		for rows.Next() {
+			var s models.Stock
+			rows.Scan(&s.ID, &s.ItemID, &s.LocationID, &s.Quantity)
+			stocks = append(stocks, s)
+		}
+		json.NewEncoder(w).Encode(map[string]interface{}{"stock": stocks})
+
+	case http.MethodPost:
+		var body models.Stock
+		json.NewDecoder(r.Body).Decode(&body)
+
+		res, err := storage.DB.Exec("INSERT INTO stock(item_id, location_id, quantity) VALUES(?, ?, ?)",
+			body.ItemID, body.LocationID, body.Quantity)
+		if err != nil {
+			http.Error(w, "Failed to link stock. Ensure Item and Location exist.", http.StatusBadRequest)
+			return
+		}
+
+		lastID, _ := res.LastInsertId()
+		body.ID = int(lastID)
+		w.WriteHeader(http.StatusCreated)
+		json.NewEncoder(w).Encode(body)
+
+	case http.MethodPut:
+		idStr := r.URL.Query().Get("id")
+		id, _ := strconv.Atoi(idStr)
+
+		var body models.Stock
+		json.NewDecoder(r.Body).Decode(&body)
+
+		res, err := storage.DB.Exec("UPDATE stock SET item_id = ?, location_id = ?, quantity = ? WHERE id = ?",
+			body.ItemID, body.LocationID, body.Quantity, id)
+		if err != nil {
+			http.Error(w, "Failed to update stock. Verify Foreign Keys.", http.StatusBadRequest)
+			return
+		}
+
+		rowsAffected, _ := res.RowsAffected()
+		if rowsAffected == 0 {
+			http.Error(w, "Stock entry not found", http.StatusNotFound)
+			return
+		}
+		body.ID = id
+		json.NewEncoder(w).Encode(body)
+
+	case http.MethodDelete:
+		idStr := r.URL.Query().Get("id")
+		id, _ := strconv.Atoi(idStr)
+
+		res, _ := storage.DB.Exec("DELETE FROM stock WHERE id = ?", id)
+		rowsAffected, _ := res.RowsAffected()
+		if rowsAffected == 0 {
+			http.Error(w, "Stock entry not found", http.StatusNotFound)
+			return
+		}
+		w.WriteHeader(http.StatusNoContent)
+
+	default:
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+	}
+}
+func Associations(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+
+	switch r.Method {
+	case http.MethodGet:
+		idStr := r.URL.Query().Get("id")
+		projectIDStr := r.URL.Query().Get("project_id")
+
+		if projectIDStr != "" {
+			pID, _ := strconv.Atoi(projectIDStr)
+			rows, err := storage.DB.Query("SELECT id, item_id, project_id, quantity FROM project_items WHERE project_id = ?", pID)
+			if err != nil {
+				http.Error(w, "Internal server error", http.StatusInternalServerError)
+				return
+			}
+			defer rows.Close()
+
+			list := []models.ProjectItem{}
+			for rows.Next() {
+				var pi models.ProjectItem
+				rows.Scan(&pi.ID, &pi.ItemID, &pi.ProjectID, &pi.Quantity)
+				list = append(list, pi)
+			}
+			json.NewEncoder(w).Encode(map[string]interface{}{"associations": list})
+			return
+		}
+
+		if idStr != "" {
+			id, _ := strconv.Atoi(idStr)
+			var pi models.ProjectItem
+			err := storage.DB.QueryRow("SELECT id, item_id, project_id, quantity FROM project_items WHERE id = ?", id).
+				Scan(&pi.ID, &pi.ItemID, &pi.ProjectID, &pi.Quantity)
+			if err == sql.ErrNoRows {
+				http.Error(w, "Association not found", http.StatusNotFound)
+				return
+			}
+			json.NewEncoder(w).Encode(pi)
+			return
+		}
+
+		rows, err := storage.DB.Query("SELECT id, item_id, project_id, quantity FROM project_items")
+		if err != nil {
+			http.Error(w, "Internal server error", http.StatusInternalServerError)
+			return
+		}
+		defer rows.Close()
+
+		all := []models.ProjectItem{}
+		for rows.Next() {
+			var pi models.ProjectItem
+			rows.Scan(&pi.ID, &pi.ItemID, &pi.ProjectID, &pi.Quantity)
+			all = append(all, pi)
+		}
+		json.NewEncoder(w).Encode(map[string]interface{}{"associations": all})
+
+	case http.MethodPost:
+		var body models.ProjectItem
+		json.NewDecoder(r.Body).Decode(&body)
+
+		res, err := storage.DB.Exec("INSERT INTO project_items(item_id, project_id, quantity) VALUES(?, ?, ?)",
+			body.ItemID, body.ProjectID, body.Quantity)
+		if err != nil {
+			http.Error(w, "Link failed. Check item_id and project_id.", http.StatusBadRequest)
+			return
+		}
+
+		lastID, _ := res.LastInsertId()
+		body.ID = int(lastID)
+		w.WriteHeader(http.StatusCreated)
+		json.NewEncoder(w).Encode(body)
+
+	case http.MethodPut:
+		idStr := r.URL.Query().Get("id")
+		id, _ := strconv.Atoi(idStr)
+
+		var body models.ProjectItem
+		json.NewDecoder(r.Body).Decode(&body)
+
+		res, err := storage.DB.Exec("UPDATE project_items SET item_id = ?, project_id = ?, quantity = ? WHERE id = ?",
+			body.ItemID, body.ProjectID, body.Quantity, id)
+		if err != nil {
+			http.Error(w, "Update failed. Check Constraints.", http.StatusBadRequest)
+			return
+		}
+
+		rowsAffected, _ := res.RowsAffected()
+		if rowsAffected == 0 {
+			http.Error(w, "Association not found", http.StatusNotFound)
+			return
+		}
+		body.ID = id
+		json.NewEncoder(w).Encode(body)
+
+	case http.MethodDelete:
+		idStr := r.URL.Query().Get("id")
+		id, _ := strconv.Atoi(idStr)
+
+		res, _ := storage.DB.Exec("DELETE FROM project_items WHERE id = ?", id)
+		rowsAffected, _ := res.RowsAffected()
+		if rowsAffected == 0 {
+			http.Error(w, "Association not found", http.StatusNotFound)
+			return
+		}
+		w.WriteHeader(http.StatusNoContent)
+
+	default:
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+	}
+}

handlers/items.go

@@ -1,41 +0,0 @@
-package handlers
-
-import (
-	"MiauInv/models"
-	"MiauInv/storage"
-	"encoding/json"
-	"net/http"
-)
-
-func GetItems(w http.ResponseWriter, r *http.Request) {
-
-	items, err := storage.GetItems()
-
-	if err != nil {
-		http.Error(w, err.Error(), 500)
-		return
-	}
-
-	json.NewEncoder(w).Encode(items)
-}
-
-func CreateItem(w http.ResponseWriter, r *http.Request) {
-
-	var item models.Item
-
-	err := json.NewDecoder(r.Body).Decode(&item)
-
-	if err != nil {
-		http.Error(w, err.Error(), 400)
-		return
-	}
-
-	err = storage.AddItem(item)
-
-	if err != nil {
-		http.Error(w, err.Error(), 500)
-		return
-	}
-
-	w.WriteHeader(http.StatusCreated)
-}

handlers/locations.go

@@ -1,20 +0,0 @@
-package handlers
-
-import (
-	"MiauInv/storage"
-	"net/http"
-)
-
-func CreateLocation(w http.ResponseWriter, r *http.Request) {
-	name := r.FormValue("name")
-
-	_, err := storage.DB.Exec(
-		"INSERT INTO locations(name) VALUES(?)",
-		name,
-	)
-
-	if err != nil {
-		http.Error(w, err.Error(), 500)
-		return
-	}
-}

handlers/passkeys.go

@@ -0,0 +1,580 @@
+package handlers
+
+import (
+	"MiauInv/auth"
+	"MiauInv/models"
+	"MiauInv/storage"
+	utils "MiauInv/util"
+	"bytes"
+	"encoding/json"
+	"errors"
+	"io"
+	"log"
+	"net"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+
+	"github.com/go-webauthn/webauthn/protocol"
+	"github.com/go-webauthn/webauthn/webauthn"
+)
+
+const passkeyChallengeTTL = 5 * time.Minute
+
+type passkeyWebAuthnUser struct {
+	user        models.User
+	credentials []webauthn.Credential
+}
+
+func (user passkeyWebAuthnUser) WebAuthnID() []byte {
+	return []byte(user.user.ID)
+}
+
+func (user passkeyWebAuthnUser) WebAuthnName() string {
+	return user.user.Username
+}
+
+func (user passkeyWebAuthnUser) WebAuthnDisplayName() string {
+	return user.user.Username
+}
+
+func (user passkeyWebAuthnUser) WebAuthnCredentials() []webauthn.Credential {
+	return user.credentials
+}
+
+func Passkeys(w http.ResponseWriter, r *http.Request) {
+	switch r.Method {
+	case http.MethodGet:
+		listPasskeys(w, r)
+	case http.MethodDelete:
+		deletePasskey(w, r)
+	default:
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+	}
+}
+
+func PasskeyRegisterOptions(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	var req struct {
+		Name     string `json:"name"`
+		Password string `json:"password"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		log.Println("POST [api/passkeys/register/options] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid request", http.StatusBadRequest)
+		return
+	}
+
+	if strings.TrimSpace(req.Password) == "" {
+		http.Error(w, "Current password required", http.StatusBadRequest)
+		return
+	}
+
+	claims := r.Context().Value(auth.UserContextKey).(*auth.Claims)
+	user, err := storage.GetUserById(claims.UserID)
+	if err != nil {
+		log.Println("POST [api/passkeys/register/options] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "User not found", http.StatusNotFound)
+		return
+	}
+
+	if !auth.CheckPasswordHash(req.Password, user.Password) {
+		http.Error(w, "Invalid password", http.StatusUnauthorized)
+		return
+	}
+
+	waUser, err := loadPasskeyWebAuthnUser(user)
+	if err != nil {
+		log.Println("POST [api/passkeys/register/options] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not load passkeys", http.StatusInternalServerError)
+		return
+	}
+
+	wa, err := webAuthnForRequest(r)
+	if err != nil {
+		log.Println("POST [api/passkeys/register/options] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid WebAuthn origin", http.StatusBadRequest)
+		return
+	}
+
+	creation, sessionData, err := wa.BeginRegistration(waUser,
+		webauthn.WithResidentKeyRequirement(protocol.ResidentKeyRequirementRequired),
+		webauthn.WithAuthenticatorSelection(protocol.AuthenticatorSelection{
+			RequireResidentKey: protocol.ResidentKeyRequired(),
+			ResidentKey:        protocol.ResidentKeyRequirementRequired,
+			UserVerification:   protocol.VerificationRequired,
+		}),
+		webauthn.WithExclusions(webauthn.Credentials(waUser.WebAuthnCredentials()).CredentialDescriptors()),
+		webauthn.WithExtensions(map[string]any{"credProps": true}),
+	)
+	if err != nil {
+		log.Println("POST [api/passkeys/register/options] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not create passkey registration challenge", http.StatusInternalServerError)
+		return
+	}
+
+	sessionToken, err := utils.GenerateOpaqueToken()
+	if err != nil {
+		log.Println("POST [api/passkeys/register/options] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not create passkey challenge", http.StatusInternalServerError)
+		return
+	}
+	if err := storage.SavePasskeyChallenge(sessionToken, user.ID, storage.PasskeyCeremonyRegister, *sessionData, passkeyChallengeTTL); err != nil {
+		log.Println("POST [api/passkeys/register/options] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not save passkey challenge", http.StatusInternalServerError)
+		return
+	}
+	_ = storage.CleanupExpiredPasskeyChallenges()
+
+	writeJSON(w, http.StatusOK, map[string]interface{}{
+		"session_token": sessionToken,
+		"options":       creation,
+	})
+	log.Println("POST [api/passkeys/register/options] " + r.RemoteAddr + ": Created passkey registration challenge")
+}
+
+func PasskeyRegisterFinish(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	var req struct {
+		SessionToken string          `json:"session_token"`
+		Name         string          `json:"name"`
+		Credential   json.RawMessage `json:"credential"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		log.Println("POST [api/passkeys/register/finish] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid request", http.StatusBadRequest)
+		return
+	}
+	if req.SessionToken == "" || len(req.Credential) == 0 {
+		http.Error(w, "Session token and credential required", http.StatusBadRequest)
+		return
+	}
+
+	claims := r.Context().Value(auth.UserContextKey).(*auth.Claims)
+	user, err := storage.GetUserById(claims.UserID)
+	if err != nil {
+		log.Println("POST [api/passkeys/register/finish] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "User not found", http.StatusNotFound)
+		return
+	}
+
+	challenge, sessionData, err := storage.ConsumePasskeyChallenge(req.SessionToken, storage.PasskeyCeremonyRegister)
+	if err != nil {
+		log.Println("POST [api/passkeys/register/finish] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid or expired passkey registration challenge", http.StatusUnauthorized)
+		return
+	}
+	if challenge.UserID != user.ID {
+		http.Error(w, "Invalid passkey registration challenge", http.StatusUnauthorized)
+		return
+	}
+
+	waUser, err := loadPasskeyWebAuthnUser(user)
+	if err != nil {
+		log.Println("POST [api/passkeys/register/finish] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not load passkeys", http.StatusInternalServerError)
+		return
+	}
+
+	wa, err := webAuthnForRequest(r)
+	if err != nil {
+		log.Println("POST [api/passkeys/register/finish] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid WebAuthn origin", http.StatusBadRequest)
+		return
+	}
+
+	credentialRequest := cloneRequestWithJSONBody(r, req.Credential)
+	credential, err := wa.FinishRegistration(waUser, sessionData, credentialRequest)
+	if err != nil {
+		log.Println("POST [api/passkeys/register/finish] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not verify passkey registration", http.StatusUnauthorized)
+		return
+	}
+
+	name := strings.TrimSpace(req.Name)
+	if name == "" {
+		name = "Passkey"
+	}
+	if _, err := storage.AddPasskeyCredential(user.ID, name, credential); err != nil {
+		log.Println("POST [api/passkeys/register/finish] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not save passkey", http.StatusInternalServerError)
+		return
+	}
+
+	if err := storage.RevokeAllRefreshTokensForUser(user.ID); err != nil {
+		log.Println("POST [api/passkeys/register/finish] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not revoke old sessions", http.StatusInternalServerError)
+		return
+	}
+
+	passkeys, _ := storage.ListPasskeyCredentials(user.ID)
+	issueLoginSessionWithExtra(w, r, user, map[string]interface{}{
+		"passkeys_enabled": true,
+		"passkey_count":    len(passkeys),
+		"passkeys":         publicPasskeys(passkeys),
+	})
+	log.Println("POST [api/passkeys/register/finish] " + r.RemoteAddr + ": Registered passkey and revoked old sessions")
+}
+
+func PasskeyLoginOptions(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	wa, err := webAuthnForRequest(r)
+	if err != nil {
+		log.Println("POST [api/passkeys/login/options] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid WebAuthn origin", http.StatusBadRequest)
+		return
+	}
+
+	assertion, sessionData, err := wa.BeginDiscoverableLogin(webauthn.WithUserVerification(protocol.VerificationRequired))
+	if err != nil {
+		log.Println("POST [api/passkeys/login/options] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not create passkey login challenge", http.StatusInternalServerError)
+		return
+	}
+
+	sessionToken, err := utils.GenerateOpaqueToken()
+	if err != nil {
+		log.Println("POST [api/passkeys/login/options] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not create passkey challenge", http.StatusInternalServerError)
+		return
+	}
+	if err := storage.SavePasskeyChallenge(sessionToken, "", storage.PasskeyCeremonyLogin, *sessionData, passkeyChallengeTTL); err != nil {
+		log.Println("POST [api/passkeys/login/options] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not save passkey challenge", http.StatusInternalServerError)
+		return
+	}
+	_ = storage.CleanupExpiredPasskeyChallenges()
+
+	writeJSON(w, http.StatusOK, map[string]interface{}{
+		"session_token": sessionToken,
+		"options":       assertion,
+	})
+	log.Println("POST [api/passkeys/login/options] " + r.RemoteAddr + ": Created passkey login challenge")
+}
+
+func PasskeyLoginFinish(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	var req struct {
+		SessionToken string          `json:"session_token"`
+		Credential   json.RawMessage `json:"credential"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		log.Println("POST [api/passkeys/login/finish] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid request", http.StatusBadRequest)
+		return
+	}
+	if req.SessionToken == "" || len(req.Credential) == 0 {
+		http.Error(w, "Session token and credential required", http.StatusBadRequest)
+		return
+	}
+
+	challenge, sessionData, err := storage.ConsumePasskeyChallenge(req.SessionToken, storage.PasskeyCeremonyLogin)
+	if err != nil {
+		log.Println("POST [api/passkeys/login/finish] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid or expired passkey login challenge", http.StatusUnauthorized)
+		return
+	}
+
+	wa, err := webAuthnForRequest(r)
+	if err != nil {
+		log.Println("POST [api/passkeys/login/finish] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid WebAuthn origin", http.StatusBadRequest)
+		return
+	}
+
+	credentialRequest := cloneRequestWithJSONBody(r, req.Credential)
+
+	var user models.User
+	var credential *webauthn.Credential
+	if challenge.UserID == "" {
+		var webAuthnUser webauthn.User
+		webAuthnUser, credential, err = wa.FinishPasskeyLogin(passkeyDiscoverableUserHandler, sessionData, credentialRequest)
+		if err == nil {
+			resolvedUser, ok := webAuthnUser.(passkeyWebAuthnUser)
+			if !ok {
+				err = errors.New("invalid passkey user type")
+			} else {
+				user = resolvedUser.user
+			}
+		}
+	} else {
+		user, err = storage.GetUserById(challenge.UserID)
+		if err == nil {
+			waUser, loadErr := loadPasskeyWebAuthnUser(user)
+			if loadErr != nil {
+				err = loadErr
+			} else {
+				credential, err = wa.FinishLogin(waUser, sessionData, credentialRequest)
+			}
+		}
+	}
+	if err != nil {
+		log.Println("POST [api/passkeys/login/finish] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not verify passkey login", http.StatusUnauthorized)
+		return
+	}
+
+	if err := storage.UpdatePasskeyCredentialAfterLogin(user.ID, credential); err != nil {
+		log.Println("POST [api/passkeys/login/finish] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not update passkey", http.StatusInternalServerError)
+		return
+	}
+
+	issueLoginSession(w, r, user)
+	log.Println("POST [api/passkeys/login/finish] " + r.RemoteAddr + ": Successfully logged in with passkey")
+}
+
+func PasskeyDisable(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	var req struct {
+		Password string `json:"password"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		log.Println("POST [api/passkeys/disable] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid request", http.StatusBadRequest)
+		return
+	}
+
+	claims := r.Context().Value(auth.UserContextKey).(*auth.Claims)
+	user, err := storage.GetUserById(claims.UserID)
+	if err != nil {
+		log.Println("POST [api/passkeys/disable] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "User not found", http.StatusNotFound)
+		return
+	}
+	if !auth.CheckPasswordHash(req.Password, user.Password) {
+		http.Error(w, "Invalid password", http.StatusUnauthorized)
+		return
+	}
+
+	if err := storage.DeleteAllPasskeyCredentials(user.ID); err != nil {
+		log.Println("POST [api/passkeys/disable] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not disable passkeys", http.StatusInternalServerError)
+		return
+	}
+	if err := storage.RevokeAllRefreshTokensForUser(user.ID); err != nil {
+		log.Println("POST [api/passkeys/disable] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not revoke old sessions", http.StatusInternalServerError)
+		return
+	}
+
+	issueLoginSessionWithExtra(w, r, user, map[string]interface{}{
+		"passkeys_enabled": false,
+		"passkey_count":    0,
+		"passkeys":         []map[string]interface{}{},
+	})
+	log.Println("POST [api/passkeys/disable] " + r.RemoteAddr + ": Disabled passkeys and revoked old sessions")
+}
+
+func listPasskeys(w http.ResponseWriter, r *http.Request) {
+	claims := r.Context().Value(auth.UserContextKey).(*auth.Claims)
+	passkeys, err := storage.ListPasskeyCredentials(claims.UserID)
+	if err != nil {
+		log.Println("GET [api/passkeys] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not load passkeys", http.StatusInternalServerError)
+		return
+	}
+
+	writeJSON(w, http.StatusOK, map[string]interface{}{
+		"passkeys":         publicPasskeys(passkeys),
+		"passkeys_enabled": len(passkeys) > 0,
+		"passkey_count":    len(passkeys),
+	})
+}
+
+func deletePasskey(w http.ResponseWriter, r *http.Request) {
+	var req struct {
+		ID       string `json:"id"`
+		Password string `json:"password"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		log.Println("DELETE [api/passkeys] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Invalid request", http.StatusBadRequest)
+		return
+	}
+	if req.ID == "" || req.Password == "" {
+		http.Error(w, "Passkey ID and password required", http.StatusBadRequest)
+		return
+	}
+
+	claims := r.Context().Value(auth.UserContextKey).(*auth.Claims)
+	user, err := storage.GetUserById(claims.UserID)
+	if err != nil {
+		log.Println("DELETE [api/passkeys] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "User not found", http.StatusNotFound)
+		return
+	}
+	if !auth.CheckPasswordHash(req.Password, user.Password) {
+		http.Error(w, "Invalid password", http.StatusUnauthorized)
+		return
+	}
+
+	if _, err := storage.GetPasskeyCredentialByID(user.ID, req.ID); err != nil {
+		http.Error(w, "Passkey not found", http.StatusNotFound)
+		return
+	}
+	if err := storage.DeletePasskeyCredential(user.ID, req.ID); err != nil {
+		log.Println("DELETE [api/passkeys] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not delete passkey", http.StatusInternalServerError)
+		return
+	}
+	if err := storage.RevokeAllRefreshTokensForUser(user.ID); err != nil {
+		log.Println("DELETE [api/passkeys] " + r.RemoteAddr + ": " + err.Error())
+		http.Error(w, "Could not revoke old sessions", http.StatusInternalServerError)
+		return
+	}
+
+	passkeys, _ := storage.ListPasskeyCredentials(user.ID)
+	issueLoginSessionWithExtra(w, r, user, map[string]interface{}{
+		"passkeys_enabled": len(passkeys) > 0,
+		"passkey_count":    len(passkeys),
+		"passkeys":         publicPasskeys(passkeys),
+	})
+	log.Println("DELETE [api/passkeys] " + r.RemoteAddr + ": Deleted passkey and revoked old sessions")
+}
+
+func loadPasskeyWebAuthnUser(user models.User) (passkeyWebAuthnUser, error) {
+	rows, err := storage.ListPasskeyCredentials(user.ID)
+	if err != nil {
+		return passkeyWebAuthnUser{}, err
+	}
+	credentials, err := storage.DecodeWebAuthnCredentials(rows)
+	if err != nil {
+		return passkeyWebAuthnUser{}, err
+	}
+	return passkeyWebAuthnUser{user: user, credentials: credentials}, nil
+}
+
+func passkeyDiscoverableUserHandler(rawID, userHandle []byte) (webauthn.User, error) {
+	row, err := storage.GetPasskeyCredentialByCredentialID(utils.EncodeBase64URL(rawID))
+	if err != nil {
+		return nil, err
+	}
+	if row.UserID != string(userHandle) {
+		return nil, errors.New("passkey user handle mismatch")
+	}
+	user, err := storage.GetUserById(row.UserID)
+	if err != nil {
+		return nil, err
+	}
+	return loadPasskeyWebAuthnUser(user)
+}
+
+func publicPasskeys(passkeys []models.PasskeyCredential) []map[string]interface{} {
+	out := make([]map[string]interface{}, 0, len(passkeys))
+	for _, passkey := range passkeys {
+		item := map[string]interface{}{
+			"id":            passkey.ID,
+			"name":          passkey.Name,
+			"credential_id": passkey.CredentialID,
+			"created_at":    passkey.CreatedAt,
+		}
+		if passkey.LastUsedAt > 0 {
+			item["last_used_at"] = passkey.LastUsedAt
+		}
+		out = append(out, item)
+	}
+	return out
+}
+
+func webAuthnForRequest(r *http.Request) (*webauthn.WebAuthn, error) {
+	origin, rpID, err := passkeyOriginAndRPID(r)
+	if err != nil {
+		return nil, err
+	}
+
+	return webauthn.New(&webauthn.Config{
+		RPID:                        rpID,
+		RPDisplayName:               "MiauInv",
+		RPOrigins:                   []string{origin},
+		RPTopOrigins:                []string{origin},
+		RPTopOriginVerificationMode: protocol.TopOriginExplicitVerificationMode,
+		AuthenticatorSelection: protocol.AuthenticatorSelection{
+			RequireResidentKey: protocol.ResidentKeyRequired(),
+			ResidentKey:        protocol.ResidentKeyRequirementRequired,
+			UserVerification:   protocol.VerificationRequired,
+		},
+	})
+}
+
+func passkeyOriginAndRPID(r *http.Request) (string, string, error) {
+	origin := strings.TrimSpace(r.Header.Get("Origin"))
+	if origin == "" {
+		scheme := strings.TrimSpace(r.Header.Get("X-Forwarded-Proto"))
+		if scheme == "" {
+			scheme = "https"
+		}
+		host := requestHost(r)
+		if host == "" {
+			return "", "", errors.New("missing request host")
+		}
+		origin = scheme + "://" + host
+	}
+
+	parsedOrigin, err := url.Parse(origin)
+	if err != nil || parsedOrigin.Scheme == "" || parsedOrigin.Host == "" {
+		return "", "", errors.New("invalid origin")
+	}
+	if parsedOrigin.Scheme != "https" && parsedOrigin.Hostname() != "localhost" {
+		return "", "", errors.New("passkeys require HTTPS except for localhost")
+	}
+
+	originHost := strings.ToLower(parsedOrigin.Hostname())
+	allowedHost := strings.ToLower(stripPort(requestHost(r)))
+	if allowedHost != "" && originHost != allowedHost {
+		return "", "", errors.New("origin host does not match request host")
+	}
+
+	return parsedOrigin.Scheme + "://" + parsedOrigin.Host, originHost, nil
+}
+
+func requestHost(r *http.Request) string {
+	if forwardedHost := strings.TrimSpace(r.Header.Get("X-Forwarded-Host")); forwardedHost != "" {
+		parts := strings.Split(forwardedHost, ",")
+		return strings.TrimSpace(parts[0])
+	}
+	return strings.TrimSpace(r.Host)
+}
+
+func stripPort(host string) string {
+	if host == "" {
+		return ""
+	}
+	if parsedHost, _, err := net.SplitHostPort(host); err == nil {
+		return parsedHost
+	}
+	if strings.Count(host, ":") == 0 {
+		return host
+	}
+	return host
+}
+
+func cloneRequestWithJSONBody(r *http.Request, raw json.RawMessage) *http.Request {
+	clone := r.Clone(r.Context())
+	clone.Body = io.NopCloser(bytes.NewReader(raw))
+	clone.ContentLength = int64(len(raw))
+	clone.Header = r.Header.Clone()
+	clone.Header.Set("Content-Type", "application/json")
+	return clone
+}

handlers/project_items.go

@@ -1,34 +0,0 @@
-package handlers
-
-import (
-	"MiauInv/storage"
-	"encoding/json"
-	"net/http"
-)
-
-type ProjectItemRequest struct {
-	ItemID    int `json:"item_id"`
-	ProjectID int `json:"project_id"`
-	Quantity  int `json:"quantity"`
-}
-
-func AllocateToProject(w http.ResponseWriter, r *http.Request) {
-
-	var req ProjectItemRequest
-
-	json.NewDecoder(r.Body).Decode(&req)
-
-	_, err := storage.DB.Exec(`
-		INSERT INTO project_items(item_id,project_id,quantity)
-		VALUES(?,?,?)
-	`,
-		req.ItemID,
-		req.ProjectID,
-		req.Quantity,
-	)
-
-	if err != nil {
-		http.Error(w, err.Error(), 500)
-		return
-	}
-}

handlers/projects.go

@@ -1,21 +0,0 @@
-package handlers
-
-import (
-	"MiauInv/storage"
-	"net/http"
-)
-
-func CreateProject(w http.ResponseWriter, r *http.Request) {
-
-	name := r.FormValue("name")
-
-	_, err := storage.DB.Exec(
-		"INSERT INTO projects(name) VALUES(?)",
-		name,
-	)
-
-	if err != nil {
-		http.Error(w, err.Error(), 500)
-		return
-	}
-}

handlers/stock.go

@@ -1,34 +0,0 @@
-package handlers
-
-import (
-	"MiauInv/storage"
-	"encoding/json"
-	"net/http"
-)
-
-type StockRequest struct {
-	ItemID     int `json:"item_id"`
-	LocationID int `json:"location_id"`
-	Quantity   int `json:"quantity"`
-}
-
-func AddStock(w http.ResponseWriter, r *http.Request) {
-
-	var req StockRequest
-
-	json.NewDecoder(r.Body).Decode(&req)
-
-	_, err := storage.DB.Exec(`
-		INSERT INTO stock(item_id,location_id,quantity)
-		VALUES(?,?,?)
-	`,
-		req.ItemID,
-		req.LocationID,
-		req.Quantity,
-	)
-
-	if err != nil {
-		http.Error(w, err.Error(), 500)
-		return
-	}
-}

models/constants.go

@@ -1,5 +1,7 @@
 package models
 
+var JWTSecret []byte
+
 // Roles
 const (
 	RoleUser  = "user"

models/dbmodels.go

@@ -5,4 +5,6 @@ type User struct {
 	Username         string `json:"username"`
 	Password         string `json:"password"`
 	Role             string `json:"role"`
+	TwoFactorEnabled bool   `json:"two_factor_enabled"`
+	TwoFactorSecret  string `json:"-"`
 }

models/inventory.go

@@ -5,7 +5,8 @@ type Item struct {
 	Name          string `json:"name"`
 	Category      string `json:"category"`
 	Description   string `json:"description"`
-	TotalQuantity int    `json:"total_quantity"`
+	TotalQuantity int    `json:"total_quantity"` // Berechnet aus der Summe aller Stocks
+	FreeQuantity  int    `json:"free_quantity"`  // TotalQuantity minus Summe aller Projekt-Zuweisungen
 }
 
 type Location struct {
@@ -24,6 +25,15 @@ type Stock struct {
 	ItemID       int    `json:"item_id"`
 	LocationID   int    `json:"location_id"`
 	Quantity     int    `json:"quantity"`
+	LocationName string `json:"location_name"` // Used to display the location in the modal table
+}
+
+type Association struct {
+	ID        int    `json:"id"`
+	ProjectID int    `json:"project_id"`
+	ItemID    int    `json:"item_id"`
+	Quantity  int    `json:"quantity"`
+	ItemName  string `json:"item_name"` // Used to display the item name in the modal table
 }
 
 type ProjectItem struct {
@@ -32,3 +42,25 @@ type ProjectItem struct {
 	ProjectID int `json:"project_id"`
 	Quantity  int `json:"quantity"`
 }
+
+type ItemExtended struct {
+	ID            int    `json:"id"`
+	Name          string `json:"name"`
+	Category      string `json:"category"`
+	Description   string `json:"description"`
+	TotalQuantity int    `json:"total_quantity"`     // Summe aus allen Stock-Einträgen
+	AllocatedQty  int    `json:"allocated_quantity"` // Summe aus allen Projekt-Zuweisungen
+	AvailableQty  int    `json:"available_quantity"` // Total - Allocated
+}
+
+type LocationContent struct {
+	ItemID   int    `json:"item_id"`
+	ItemName string `json:"item_name"`
+	Quantity int    `json:"quantity"`
+}
+
+type ProjectDetailItem struct {
+	ItemID   int    `json:"item_id"`
+	ItemName string `json:"item_name"`
+	Quantity int    `json:"quantity"`
+}

models/passkeys.go

@@ -0,0 +1,19 @@
+package models
+
+type PasskeyCredential struct {
+	ID             string `json:"id"`
+	UserID         string `json:"user_id"`
+	CredentialID   string `json:"credential_id"`
+	Name           string `json:"name"`
+	CredentialData string `json:"-"`
+	CreatedAt      int64  `json:"created_at"`
+	LastUsedAt     int64  `json:"last_used_at,omitempty"`
+}
+
+type PasskeyChallenge struct {
+	Token       string `json:"token"`
+	UserID      string `json:"user_id"`
+	Ceremony    string `json:"ceremony"`
+	SessionData string `json:"-"`
+	ExpiresAt   int64  `json:"expires_at"`
+}

server/ratelimit.go

@@ -0,0 +1,101 @@
+package server
+
+import (
+	"log"
+	"net"
+	"net/http"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+)
+
+type rateLimitState struct {
+	count        int
+	resetAt      time.Time
+	blockedUntil time.Time
+}
+
+type rateLimiter struct {
+	mu          sync.Mutex
+	states      map[string]*rateLimitState
+	maxRequests int
+	window      time.Duration
+	blockFor    time.Duration
+}
+
+func newRateLimiter(maxRequests int, window, blockFor time.Duration) *rateLimiter {
+	return &rateLimiter{
+		states:      make(map[string]*rateLimitState),
+		maxRequests: maxRequests,
+		window:      window,
+		blockFor:    blockFor,
+	}
+}
+
+func (limiter *rateLimiter) Middleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if !limiter.allow(r) {
+			w.Header().Set("Retry-After", strconvSeconds(limiter.blockFor))
+			http.Error(w, "Too many requests", http.StatusTooManyRequests)
+			return
+		}
+		next.ServeHTTP(w, r)
+	})
+}
+
+func (limiter *rateLimiter) allow(r *http.Request) bool {
+	key := clientIP(r) + ":" + r.URL.Path
+	now := time.Now()
+
+	limiter.mu.Lock()
+	defer limiter.mu.Unlock()
+
+	state, ok := limiter.states[key]
+	if ok && now.Before(state.blockedUntil) {
+		return false
+	}
+
+	if !ok || now.After(state.resetAt) {
+		limiter.states[key] = &rateLimitState{
+			count:   1,
+			resetAt: now.Add(limiter.window),
+		}
+		return true
+	}
+
+	state.count++
+	if state.count > limiter.maxRequests {
+		state.blockedUntil = now.Add(limiter.blockFor)
+		state.resetAt = now.Add(limiter.window)
+		state.count = 0
+		log.Printf("Rate limit triggered for %s on %s", clientIP(r), r.URL.Path)
+		return false
+	}
+
+	return true
+}
+
+func clientIP(r *http.Request) string {
+	if forwardedFor := r.Header.Get("X-Forwarded-For"); forwardedFor != "" {
+		parts := strings.Split(forwardedFor, ",")
+		if ip := strings.TrimSpace(parts[0]); ip != "" {
+			return ip
+		}
+	}
+	if realIP := strings.TrimSpace(r.Header.Get("X-Real-IP")); realIP != "" {
+		return realIP
+	}
+	if host, _, err := net.SplitHostPort(r.RemoteAddr); err == nil {
+		return host
+	}
+	return r.RemoteAddr
+}
+
+func strconvSeconds(duration time.Duration) string {
+	seconds := int(duration.Seconds())
+	if seconds < 1 {
+		seconds = 1
+	}
+	return strconv.Itoa(seconds)
+}

server/server.go

@@ -1,12 +1,16 @@
 package server
 
 import (
+	"MiauInv/auth"
 	"MiauInv/config"
 	"MiauInv/frontend"
 	"MiauInv/handlers"
+	"MiauInv/models"
+	utils "MiauInv/util"
 	"log"
 	"net/http"
 	"os"
+	"time"
 )
 
 type Server struct {
@@ -15,6 +19,7 @@ type Server struct {
 	DatabasePath      string
 	CertificatePath   string
 	PrivateKeyPath    string
+	AllowRegistration bool
 }
 
 func InitServer() *Server {
@@ -41,12 +46,15 @@ func InitServer() *Server {
 		return nil
 	}
 
+	models.JWTSecret = []byte(jwtSecret)
+
 	return &Server{
 		Port:              cfg.Port,
 		JWTSecret:         []byte(jwtSecret),
 		DatabasePath:      cfg.DatabasePath,
 		CertificatePath:   cfg.CertificatePath,
 		PrivateKeyPath:    cfg.PrivateKeyPath,
+		AllowRegistration: cfg.AllowRegistration,
 	}
 }
 
@@ -58,28 +66,56 @@ func (this *Server) Run() {
 	// FRONTEND
 	//
 	mux.HandleFunc("/", frontend.Home)
-	mux.HandleFunc("/dashboard", frontend.Dashboard)
+	mux.HandleFunc("/login", utils.RenderFile("frontend/htmx/login.html"))
+	mux.Handle("/dashboard", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(frontend.Dashboard)))
+	mux.Handle("/inventory", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(frontend.Inventory)))
+	mux.Handle("/items", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(frontend.Items)))
+	mux.Handle("/locations", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(frontend.Locations)))
+	mux.Handle("/projects", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(frontend.Projects)))
+	mux.Handle("/profile/settings", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(frontend.AccountSettings)))
+	mux.HandleFunc("/profile/", utils.RenderFile("frontend/htmx/under-construction.html"))
+	if this.AllowRegistration {
+		mux.HandleFunc("/register", utils.RenderFile("frontend/htmx/register.html"))
+	} else {
+		mux.HandleFunc("/register", utils.RenderFile("frontend/htmx/register-blocked.html"))
+	}
 
 	//
 	// API
 	//
+	loginLimiter := newRateLimiter(10, time.Minute, 5*time.Minute)
+	accountLimiter := newRateLimiter(20, time.Minute, 2*time.Minute)
 
-	// Public
-	mux.HandleFunc("/api/login", handlers.Login)
-	mux.HandleFunc("/api/register", handlers.Register)
-	mux.HandleFunc("/api/refresh", handlers.RefreshToken)
-	mux.HandleFunc("/api/logout", handlers.Logout)
+	mux.Handle("/api/login", loginLimiter.Middleware(http.HandlerFunc(handlers.APILogin)))
+	mux.Handle("/api/login/2fa", loginLimiter.Middleware(http.HandlerFunc(handlers.APILoginTwoFactor)))
+	mux.Handle("/api/refresh", loginLimiter.Middleware(http.HandlerFunc(handlers.RefreshToken)))
+	mux.Handle("/api/logout", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.Logout)))
+	mux.Handle("/api/profile", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.UserInfo)))
+	mux.Handle("/api/2fa/setup", accountLimiter.Middleware(auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.TwoFactorSetup))))
+	mux.Handle("/api/2fa/enable", loginLimiter.Middleware(auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.TwoFactorEnable))))
+	mux.Handle("/api/2fa/disable", loginLimiter.Middleware(auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.TwoFactorDisable))))
+	mux.Handle("/api/2fa/recovery-codes/regenerate", loginLimiter.Middleware(auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.TwoFactorRegenerateRecoveryCodes))))
+	mux.Handle("/api/userinfo", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.UserInfo)))
+	mux.Handle("/api/account/username", accountLimiter.Middleware(auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.AccountUpdateUsername))))
+	mux.Handle("/api/account/password", loginLimiter.Middleware(auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.AccountUpdatePassword))))
+	mux.Handle("/api/passkeys", accountLimiter.Middleware(auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.Passkeys))))
+	mux.Handle("/api/passkeys/register/options", accountLimiter.Middleware(auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.PasskeyRegisterOptions))))
+	mux.Handle("/api/passkeys/register/finish", accountLimiter.Middleware(auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.PasskeyRegisterFinish))))
+	mux.Handle("/api/passkeys/disable", loginLimiter.Middleware(auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.PasskeyDisable))))
+	mux.Handle("/api/passkeys/login/options", loginLimiter.Middleware(http.HandlerFunc(handlers.PasskeyLoginOptions)))
+	mux.Handle("/api/passkeys/login/finish", loginLimiter.Middleware(http.HandlerFunc(handlers.PasskeyLoginFinish)))
+	if this.AllowRegistration {
+		mux.Handle("/api/register", loginLimiter.Middleware(http.HandlerFunc(handlers.APIRegister)))
+	}
 
-	mux.HandleFunc("/api/items", handlers.GetItems)
-	mux.HandleFunc("/api/items/create", handlers.CreateItem)
-	mux.HandleFunc("/api/locations/create", handlers.CreateLocation)
-	mux.HandleFunc("/api/projects/create", handlers.CreateProject)
-	mux.HandleFunc("/api/stock/add", handlers.AddStock)
-	mux.HandleFunc("/api/project-items/add", handlers.AllocateToProject)
+	mux.Handle("/api/item", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.Item)))
+	mux.Handle("/api/location", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.Location)))
+	mux.Handle("/api/project", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.Project)))
+	mux.Handle("/api/stock", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.Stock)))
+	mux.Handle("/api/association", auth.AuthMiddleware(this.JWTSecret)(http.HandlerFunc(handlers.Associations)))
 
-	// Login required
-
-	// Admin-only
+	// Assets
+	mux.HandleFunc("/assets/", frontend.Assets)
 
 	log.Printf("Listening on port %s", this.Port)
 	log.Fatal(http.ListenAndServeTLS(":"+this.Port, this.CertificatePath, this.PrivateKeyPath, mux))

storage/passkeys.go

@@ -0,0 +1,262 @@
+package storage
+
+import (
+	"MiauInv/models"
+	utils "MiauInv/util"
+	"database/sql"
+	"encoding/json"
+	"errors"
+	"time"
+
+	"github.com/go-webauthn/webauthn/webauthn"
+)
+
+const (
+	PasskeyCeremonyRegister = "register"
+	PasskeyCeremonyLogin    = "login"
+)
+
+func AddPasskeyCredential(userID, name string, credential *webauthn.Credential) (models.PasskeyCredential, error) {
+	if DB == nil {
+		return models.PasskeyCredential{}, errors.New("db not initialized")
+	}
+
+	credentialJSON, err := json.Marshal(credential)
+	if err != nil {
+		return models.PasskeyCredential{}, err
+	}
+
+	row := models.PasskeyCredential{
+		ID:             utils.GenerateUUID(),
+		UserID:         userID,
+		CredentialID:   utils.EncodeBase64URL(credential.ID),
+		Name:           name,
+		CredentialData: string(credentialJSON),
+		CreatedAt:      time.Now().Unix(),
+	}
+	if row.Name == "" {
+		row.Name = "Passkey"
+	}
+
+	_, err = DB.Exec(`
+		INSERT INTO passkey_credentials(id, user_id, credential_id, name, credential_data, created_at, last_used_at)
+		VALUES (?, ?, ?, ?, ?, ?, NULL)
+	`, row.ID, row.UserID, row.CredentialID, row.Name, row.CredentialData, row.CreatedAt)
+	if err != nil {
+		return models.PasskeyCredential{}, err
+	}
+
+	return row, nil
+}
+
+func ListPasskeyCredentials(userID string) ([]models.PasskeyCredential, error) {
+	if DB == nil {
+		return nil, errors.New("db not initialized")
+	}
+
+	rows, err := DB.Query(`
+		SELECT id, user_id, credential_id, name, credential_data, created_at, COALESCE(last_used_at, 0)
+		FROM passkey_credentials
+		WHERE user_id = ?
+		ORDER BY created_at DESC
+	`, userID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	credentials := make([]models.PasskeyCredential, 0)
+	for rows.Next() {
+		var credential models.PasskeyCredential
+		if err := rows.Scan(&credential.ID, &credential.UserID, &credential.CredentialID, &credential.Name, &credential.CredentialData, &credential.CreatedAt, &credential.LastUsedAt); err != nil {
+			return nil, err
+		}
+		credentials = append(credentials, credential)
+	}
+	return credentials, rows.Err()
+}
+
+func CountPasskeyCredentials(userID string) (int, error) {
+	if DB == nil {
+		return 0, errors.New("db not initialized")
+	}
+
+	var count int
+	err := DB.QueryRow("SELECT COUNT(*) FROM passkey_credentials WHERE user_id = ?", userID).Scan(&count)
+	return count, err
+}
+
+func GetPasskeyCredentialByCredentialID(credentialID string) (models.PasskeyCredential, error) {
+	if DB == nil {
+		return models.PasskeyCredential{}, errors.New("db not initialized")
+	}
+
+	row := DB.QueryRow(`
+		SELECT id, user_id, credential_id, name, credential_data, created_at, COALESCE(last_used_at, 0)
+		FROM passkey_credentials
+		WHERE credential_id = ?
+	`, credentialID)
+	return scanPasskeyCredential(row)
+}
+
+func GetPasskeyCredentialByID(userID, id string) (models.PasskeyCredential, error) {
+	if DB == nil {
+		return models.PasskeyCredential{}, errors.New("db not initialized")
+	}
+
+	row := DB.QueryRow(`
+		SELECT id, user_id, credential_id, name, credential_data, created_at, COALESCE(last_used_at, 0)
+		FROM passkey_credentials
+		WHERE user_id = ? AND id = ?
+	`, userID, id)
+	return scanPasskeyCredential(row)
+}
+
+func scanPasskeyCredential(row *sql.Row) (models.PasskeyCredential, error) {
+	var credential models.PasskeyCredential
+	err := row.Scan(&credential.ID, &credential.UserID, &credential.CredentialID, &credential.Name, &credential.CredentialData, &credential.CreatedAt, &credential.LastUsedAt)
+	return credential, err
+}
+
+func DecodeWebAuthnCredential(row models.PasskeyCredential) (webauthn.Credential, error) {
+	var credential webauthn.Credential
+	err := json.Unmarshal([]byte(row.CredentialData), &credential)
+	return credential, err
+}
+
+func DecodeWebAuthnCredentials(rows []models.PasskeyCredential) ([]webauthn.Credential, error) {
+	credentials := make([]webauthn.Credential, 0, len(rows))
+	for _, row := range rows {
+		credential, err := DecodeWebAuthnCredential(row)
+		if err != nil {
+			return nil, err
+		}
+		credentials = append(credentials, credential)
+	}
+	return credentials, nil
+}
+
+func UpdatePasskeyCredentialAfterLogin(userID string, credential *webauthn.Credential) error {
+	if DB == nil {
+		return errors.New("db not initialized")
+	}
+
+	credentialID := utils.EncodeBase64URL(credential.ID)
+	credentialJSON, err := json.Marshal(credential)
+	if err != nil {
+		return err
+	}
+
+	res, err := DB.Exec(`
+		UPDATE passkey_credentials
+		SET credential_data = ?, last_used_at = ?
+		WHERE user_id = ? AND credential_id = ?
+	`, string(credentialJSON), time.Now().Unix(), userID, credentialID)
+	if err != nil {
+		return err
+	}
+	n, err := res.RowsAffected()
+	if err != nil {
+		return err
+	}
+	if n == 0 {
+		return ErrNotFound
+	}
+	return nil
+}
+
+func DeletePasskeyCredential(userID, id string) error {
+	if DB == nil {
+		return errors.New("db not initialized")
+	}
+
+	res, err := DB.Exec("DELETE FROM passkey_credentials WHERE user_id = ? AND id = ?", userID, id)
+	if err != nil {
+		return err
+	}
+	n, err := res.RowsAffected()
+	if err != nil {
+		return err
+	}
+	if n == 0 {
+		return ErrNotFound
+	}
+	return nil
+}
+
+func DeleteAllPasskeyCredentials(userID string) error {
+	if DB == nil {
+		return errors.New("db not initialized")
+	}
+
+	_, err := DB.Exec("DELETE FROM passkey_credentials WHERE user_id = ?", userID)
+	return err
+}
+
+func SavePasskeyChallenge(token, userID, ceremony string, sessionData webauthn.SessionData, ttl time.Duration) error {
+	if DB == nil {
+		return errors.New("db not initialized")
+	}
+
+	encodedSession, err := json.Marshal(sessionData)
+	if err != nil {
+		return err
+	}
+
+	_, err = DB.Exec(`
+		INSERT INTO passkey_challenges(token, user_id, ceremony, session_data, expires_at)
+		VALUES (?, ?, ?, ?, ?)
+	`, token, userID, ceremony, string(encodedSession), time.Now().Add(ttl).Unix())
+	return err
+}
+
+func ConsumePasskeyChallenge(token, ceremony string) (models.PasskeyChallenge, webauthn.SessionData, error) {
+	if DB == nil {
+		return models.PasskeyChallenge{}, webauthn.SessionData{}, errors.New("db not initialized")
+	}
+
+	tx, err := DB.Begin()
+	if err != nil {
+		return models.PasskeyChallenge{}, webauthn.SessionData{}, err
+	}
+	defer tx.Rollback()
+
+	row := tx.QueryRow(`
+		SELECT token, user_id, ceremony, session_data, expires_at
+		FROM passkey_challenges
+		WHERE token = ? AND ceremony = ?
+	`, token, ceremony)
+
+	var challenge models.PasskeyChallenge
+	if err := row.Scan(&challenge.Token, &challenge.UserID, &challenge.Ceremony, &challenge.SessionData, &challenge.ExpiresAt); err != nil {
+		return models.PasskeyChallenge{}, webauthn.SessionData{}, err
+	}
+
+	if _, err := tx.Exec("DELETE FROM passkey_challenges WHERE token = ?", token); err != nil {
+		return models.PasskeyChallenge{}, webauthn.SessionData{}, err
+	}
+
+	if challenge.ExpiresAt < time.Now().Unix() {
+		return models.PasskeyChallenge{}, webauthn.SessionData{}, errors.New("passkey challenge expired")
+	}
+
+	var sessionData webauthn.SessionData
+	if err := json.Unmarshal([]byte(challenge.SessionData), &sessionData); err != nil {
+		return models.PasskeyChallenge{}, webauthn.SessionData{}, err
+	}
+
+	if err := tx.Commit(); err != nil {
+		return models.PasskeyChallenge{}, webauthn.SessionData{}, err
+	}
+
+	return challenge, sessionData, nil
+}
+
+func CleanupExpiredPasskeyChallenges() error {
+	if DB == nil {
+		return errors.New("db not initialized")
+	}
+
+	_, err := DB.Exec("DELETE FROM passkey_challenges WHERE expires_at < ?", time.Now().Unix())
+	return err
+}

storage/storage.go

@@ -2,10 +2,12 @@ package storage
 
 import (
 	"MiauInv/models"
+	utils "MiauInv/util"
 	"database/sql"
 	"errors"
 	"log"
 	"strings"
+	"time"
 
 	_ "github.com/glebarez/go-sqlite"
 )
@@ -27,7 +29,9 @@ func InitDB(filepath string) error {
         id TEXT PRIMARY KEY,
         username TEXT NOT NULL UNIQUE,
         password TEXT NOT NULL,
-        role TEXT NOT NULL
+        role TEXT NOT NULL,
+        two_factor_enabled INTEGER NOT NULL DEFAULT 0,
+        two_factor_secret TEXT NOT NULL DEFAULT ''
     );
 
     CREATE TABLE IF NOT EXISTS refresh_tokens (
@@ -41,6 +45,35 @@ func InitDB(filepath string) error {
         FOREIGN KEY(user_id) REFERENCES users(id)
     );
 
+    CREATE TABLE IF NOT EXISTS two_factor_recovery_codes (
+        id TEXT PRIMARY KEY,
+        user_id TEXT NOT NULL,
+        code_hash TEXT NOT NULL,
+        created_at INTEGER NOT NULL,
+        used_at INTEGER DEFAULT NULL,
+        FOREIGN KEY(user_id) REFERENCES users(id) ON DELETE CASCADE,
+        UNIQUE(user_id, code_hash)
+    );
+
+    CREATE TABLE IF NOT EXISTS passkey_credentials (
+        id TEXT PRIMARY KEY,
+        user_id TEXT NOT NULL,
+        credential_id TEXT NOT NULL UNIQUE,
+        name TEXT NOT NULL,
+        credential_data TEXT NOT NULL,
+        created_at INTEGER NOT NULL,
+        last_used_at INTEGER DEFAULT NULL,
+        FOREIGN KEY(user_id) REFERENCES users(id) ON DELETE CASCADE
+    );
+
+    CREATE TABLE IF NOT EXISTS passkey_challenges (
+        token TEXT PRIMARY KEY,
+        user_id TEXT NOT NULL DEFAULT '',
+        ceremony TEXT NOT NULL,
+        session_data TEXT NOT NULL,
+        expires_at INTEGER NOT NULL
+    );
+
 	CREATE TABLE IF NOT EXISTS items (
 	    id INTEGER PRIMARY KEY AUTOINCREMENT,
 	    name TEXT NOT NULL,
@@ -84,27 +117,189 @@ func InitDB(filepath string) error {
 		log.Fatal(err)
 	}
 
+	if err := ensureUserTwoFactorColumns(); err != nil {
 		return err
 	}
 
+	return nil
+}
+
+func ensureUserTwoFactorColumns() error {
+	migrations := []string{
+		"ALTER TABLE users ADD COLUMN two_factor_enabled INTEGER NOT NULL DEFAULT 0",
+		"ALTER TABLE users ADD COLUMN two_factor_secret TEXT NOT NULL DEFAULT ''",
+	}
+
+	for _, migration := range migrations {
+		_, err := DB.Exec(migration)
+		if err != nil && !strings.Contains(strings.ToLower(err.Error()), "duplicate column") {
+			return err
+		}
+	}
+	return nil
+}
+
 // Users
 func AddUser(user *models.User) error {
 	_, err := DB.Exec("INSERT INTO users(id, username, password, role) VALUES (?, ?, ?, ?)", user.ID, strings.ToLower(user.Username), user.Password, user.Role)
 	return err
 }
 func GetUserByUsername(username string) (models.User, error) {
-	row := DB.QueryRow("SELECT * FROM users WHERE username = ?", strings.ToLower(username))
-	var user models.User
-	err := row.Scan(&user.ID, &user.Username, &user.Password, &user.Role)
-	return user, err
+	row := DB.QueryRow(`
+		SELECT id, username, password, role, two_factor_enabled, two_factor_secret
+		FROM users
+		WHERE username = ?
+	`, strings.ToLower(username))
+	return scanUser(row)
 }
 func GetUserById(id string) (models.User, error) {
-	row := DB.QueryRow("SELECT * FROM users WHERE id = ?", id)
+	row := DB.QueryRow(`
+		SELECT id, username, password, role, two_factor_enabled, two_factor_secret
+		FROM users
+		WHERE id = ?
+	`, id)
+	return scanUser(row)
+}
+
+func scanUser(row *sql.Row) (models.User, error) {
 	var user models.User
-	err := row.Scan(&user.ID, &user.Username, &user.Password, &user.Role)
+	var twoFactorEnabled int
+	err := row.Scan(&user.ID, &user.Username, &user.Password, &user.Role, &twoFactorEnabled, &user.TwoFactorSecret)
+	user.TwoFactorEnabled = twoFactorEnabled == 1
 	return user, err
 }
 
+func UpdateUserUsername(userID, username string) error {
+	res, err := DB.Exec("UPDATE users SET username = ? WHERE id = ?", strings.ToLower(username), userID)
+	if err != nil {
+		return err
+	}
+	n, err := res.RowsAffected()
+	if err != nil {
+		return err
+	}
+	if n == 0 {
+		return ErrNotFound
+	}
+	return nil
+}
+
+func UpdateUserPassword(userID, passwordHash string) error {
+	res, err := DB.Exec("UPDATE users SET password = ? WHERE id = ?", passwordHash, userID)
+	if err != nil {
+		return err
+	}
+	n, err := res.RowsAffected()
+	if err != nil {
+		return err
+	}
+	if n == 0 {
+		return ErrNotFound
+	}
+	return nil
+}
+
+func SetUserTwoFactorSecret(userID, secret string) error {
+	_, err := DB.Exec("UPDATE users SET two_factor_secret = ? WHERE id = ?", secret, userID)
+	return err
+}
+
+func EnableUserTwoFactorWithSecretAndRecoveryCodes(userID, twoFactorSecret string, recoveryCodeHashes []string) error {
+	tx, err := DB.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+
+	if _, err := tx.Exec("DELETE FROM two_factor_recovery_codes WHERE user_id = ?", userID); err != nil {
+		return err
+	}
+
+	now := time.Now().Unix()
+	for _, codeHash := range recoveryCodeHashes {
+		if _, err := tx.Exec(`
+			INSERT INTO two_factor_recovery_codes(id, user_id, code_hash, created_at)
+			VALUES (?, ?, ?, ?)
+		`, utils.GenerateUUID(), userID, codeHash, now); err != nil {
+			return err
+		}
+	}
+
+	if _, err := tx.Exec("UPDATE users SET two_factor_enabled = 1, two_factor_secret = ? WHERE id = ?", twoFactorSecret, userID); err != nil {
+		return err
+	}
+
+	return tx.Commit()
+}
+
+func DisableUserTwoFactor(userID string) error {
+	tx, err := DB.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+
+	if _, err := tx.Exec("UPDATE users SET two_factor_enabled = 0, two_factor_secret = '' WHERE id = ?", userID); err != nil {
+		return err
+	}
+	if _, err := tx.Exec("DELETE FROM two_factor_recovery_codes WHERE user_id = ?", userID); err != nil {
+		return err
+	}
+
+	return tx.Commit()
+}
+
+func ReplaceUserRecoveryCodes(userID string, recoveryCodeHashes []string) error {
+	tx, err := DB.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+
+	if _, err := tx.Exec("DELETE FROM two_factor_recovery_codes WHERE user_id = ?", userID); err != nil {
+		return err
+	}
+
+	now := time.Now().Unix()
+	for _, codeHash := range recoveryCodeHashes {
+		if _, err := tx.Exec(`
+			INSERT INTO two_factor_recovery_codes(id, user_id, code_hash, created_at)
+			VALUES (?, ?, ?, ?)
+		`, utils.GenerateUUID(), userID, codeHash, now); err != nil {
+			return err
+		}
+	}
+
+	return tx.Commit()
+}
+
+func UseUserRecoveryCode(userID, codeHash string) (bool, error) {
+	res, err := DB.Exec(`
+		UPDATE two_factor_recovery_codes
+		SET used_at = ?
+		WHERE user_id = ? AND code_hash = ? AND used_at IS NULL
+	`, time.Now().Unix(), userID, codeHash)
+	if err != nil {
+		return false, err
+	}
+
+	n, err := res.RowsAffected()
+	if err != nil {
+		return false, err
+	}
+	return n == 1, nil
+}
+
+func CountUnusedRecoveryCodes(userID string) (int, error) {
+	var count int
+	err := DB.QueryRow(`
+		SELECT COUNT(*)
+		FROM two_factor_recovery_codes
+		WHERE user_id = ? AND used_at IS NULL
+	`, userID).Scan(&count)
+	return count, err
+}
+
 // Refresh Tokens
 func AddRefreshToken(token *models.RefreshToken) error {
 	_, err := DB.Exec("INSERT INTO refresh_tokens(id, user_id, token_hash, expires_at, created_at, revoked, device_info) VALUES (?, ?, ?, ?, ?, ?, ?)",

util/util.go

@@ -23,12 +23,19 @@ func GenerateSecret() string {
 	return base64.StdEncoding.EncodeToString(b)
 }
 func GenerateRefreshToken() (string, error) {
+	return GenerateOpaqueToken()
+}
+
+func GenerateOpaqueToken() (string, error) {
 	b := make([]byte, 32)
 	if _, err := rand.Read(b); err != nil {
 		return "", err
 	}
 	return base64.RawURLEncoding.EncodeToString(b), nil
 }
+func EncodeBase64URL(data []byte) string {
+	return base64.RawURLEncoding.EncodeToString(data)
+}
 func HashToken(token string) string {
 	hash := sha256.Sum256([]byte(token))
 	return hex.EncodeToString(hash[:])
@@ -47,3 +54,8 @@ func IsLoggedIn(w http.ResponseWriter, r *http.Request) (*auth.Claims, bool) {
 	}
 	return claims, true
 }
+func RenderFile(path string) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		http.ServeFile(w, r, path)
+	}
+}