Fixed quantity bug

handlers/api.go

@@ -18,6 +18,32 @@ func Location(w http.ResponseWriter, r *http.Request) {
 
 	case http.MethodGet:
 		idStr := r.URL.Query().Get("id")
+		contentMode := r.URL.Query().Get("content")
+
+		if idStr != "" && contentMode == "true" {
+			_, _ = strconv.Atoi(idStr)
+			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)
+			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
+				rows.Scan(&c.ItemID, &c.ItemName, &c.Quantity)
+				contents = append(contents, c)
+			}
+			json.NewEncoder(w).Encode(map[string]interface{}{"contents": contents})
+			return
+		}
 
 		if idStr != "" {
 			id, err := strconv.Atoi(idStr)
@@ -188,46 +214,33 @@ func Item(w http.ResponseWriter, r *http.Request) {
 
 	switch r.Method {
 	case http.MethodGet:
-		idStr := r.URL.Query().Get("id")
-
-		// Read One
-		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 {
-					http.Error(w, "Item not found", http.StatusNotFound)
-					return
-				}
-				http.Error(w, "Internal server error", http.StatusInternalServerError)
-				return
-			}
-			json.NewEncoder(w).Encode(item)
-			return
-		}
-
-		// Read All
-		rows, err := storage.DB.Query("SELECT id, name, category, description, total_quantity FROM items ORDER BY name ASC")
+		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, "Internal server error", http.StatusInternalServerError)
+			http.Error(w, "Database error", http.StatusInternalServerError)
 			return
 		}
 		defer rows.Close()
 
-		items := []models.Item{}
+		var itemsExtended []models.ItemExtended
 		for rows.Next() {
-			var item models.Item
-			rows.Scan(&item.ID, &item.Name, &item.Category, &item.Description, &item.TotalQuantity)
-			items = append(items, item)
+			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": items})
+		json.NewEncoder(w).Encode(map[string]interface{}{"items": itemsExtended})
+		return
 
 	case http.MethodPost:
 		var body models.Item
@@ -304,6 +317,33 @@ func Project(w http.ResponseWriter, r *http.Request) {
 	case http.MethodGet:
 		idStr := r.URL.Query().Get("id")
 
+		detailsMode := r.URL.Query().Get("details")
+
+		if idStr != "" && detailsMode == "true" {
+			_, _ = strconv.Atoi(idStr)
+			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)
+			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
+				rows.Scan(&d.ItemID, &d.ItemName, &d.Quantity)
+				details = append(details, d)
+			}
+			json.NewEncoder(w).Encode(map[string]interface{}{"items": details})
+			return
+		}
+
 		if idStr != "" {
 			id, _ := strconv.Atoi(idStr)
 			var p models.Project