# Phase 2: Product Management - COMPLETED ✅

## Overview
Phase 2 has been successfully completed. Product and variant management system is now fully functional.

---

## ✅ Completed Tasks

### 1. Product Service ✅
- ✅ `createProduct` - Create product with optional variants
- ✅ `getProductById` - Get product by ID (with optional variants)
- ✅ `updateProduct` - Update product information
- ✅ `deleteProduct` - Delete product (not allowed - kept for audit)
- ✅ `listProducts` - List products with pagination and filters
- ✅ `searchProducts` - Search products by name or SKU

**Location:** `modules/products/services/index.js`

**Features:**
- SKU uniqueness validation
- Product type validation (FG/RM)
- Pagination support
- Search functionality
- Filtering by product_type and track_inventory

---

### 2. Product Variant Service ✅
- ✅ `createVariant` - Create variant for a product
- ✅ `getVariantById` - Get variant by ID
- ✅ `updateVariant` - Update variant information
- ✅ `deleteVariant` - Delete variant
- ✅ `listVariantsByProduct` - List variants for a product

**Location:** `modules/products/services/variants.js`

**Features:**
- Variant SKU uniqueness validation
- Variant attributes as JSON (flexible structure)
- Cascade deletion support

---

### 3. Product Controllers ✅
- ✅ `createProduct` - Handle product creation
- ✅ `getProductById` - Handle product retrieval
- ✅ `updateProduct` - Handle product updates
- ✅ `deleteProduct` - Handle product deletion
- ✅ `listProducts` - Handle product listing
- ✅ `searchProducts` - Handle product search
- ✅ `createVariant` - Handle variant creation
- ✅ `updateVariant` - Handle variant updates
- ✅ `deleteVariant` - Handle variant deletion
- ✅ `listVariants` - Handle variant listing

**Location:** `modules/products/controllers/index.js`

**Features:**
- System logging for all operations
- Audit trail for all actions
- Proper error handling

---

### 4. Product Validations ✅
- ✅ `validateCreateProduct` - Validates product creation data
- ✅ `validateUpdateProduct` - Validates product update data
- ✅ `validateGetProduct` - Validates product ID parameter
- ✅ `validateDeleteProduct` - Validates product ID for deletion
- ✅ `validateListProducts` - Validates query parameters
- ✅ `validateSearchProducts` - Validates search parameters
- ✅ `validateCreateVariant` - Validates variant creation data
- ✅ `validateUpdateVariant` - Validates variant update data
- ✅ `validateDeleteVariant` - Validates variant ID for deletion
- ✅ `validateListVariants` - Validates product ID for listing variants

**Location:** `modules/products/validations/index.js`

**Validation Rules:**
- Product name: 1-150 characters, required
- SKU: Max 100 characters, optional but unique if provided
- Product type: Must be FG or RM, required
- Variant attributes: Must be non-empty object
- Pagination: Page and limit validation

---

### 5. Product Routes ✅
- ✅ `GET /api/products` - List products (with pagination and filters)
- ✅ `GET /api/products/search` - Search products
- ✅ `GET /api/products/:id` - Get product by ID
- ✅ `POST /api/products` - Create product (manager/admin only)
- ✅ `PUT /api/products/:id` - Update product (manager/admin only)
- ✅ `DELETE /api/products/:id` - Delete product (not allowed)
- ✅ `GET /api/products/:id/variants` - List product variants
- ✅ `POST /api/products/:id/variants` - Create variant (manager/admin only)
- ✅ `PUT /api/products/:productId/variants/:variantId` - Update variant (manager/admin only)
- ✅ `DELETE /api/products/:productId/variants/:variantId` - Delete variant (manager/admin only)

**Location:** `modules/products/routes/index.js`

**Swagger Documentation:** ✅ All endpoints documented

**Authorization:**
- Create/Update/Delete: Manager/Admin only
- List/Get: Any authenticated user

---

### 6. Product Search/Filtering ✅
- ✅ Search by name or SKU
- ✅ Filter by product_type (FG/RM)
- ✅ Filter by track_inventory (true/false)
- ✅ Pagination support
- ✅ Case-insensitive search

**Implementation:** Included in `listProducts` and `searchProducts` services

---

### 7. Seed Data for Sample Products ✅
- ✅ Product seeder created
- ✅ Sample products with variants
- ✅ Includes both FG (Finished Goods) and RM (Raw Materials)
- ✅ NPM script: `npm run seed:products`

**Location:** `scripts/seeders/seedProducts.js`

**Sample Products:**
- Cotton T-Shirt (FG) - 4 variants (sizes/colors)
- Jeans (FG) - 3 variants (waist/length)
- Laptop Computer (FG) - No variants
- Mobile Phone (FG) - 3 variants (storage/color)
- Cotton Fabric (RM) - No variants
- Electronic Components (RM) - No variants

---

### 8. Image Upload (Pending) ⚠️
- ⚠️ Basic image upload functionality not yet implemented
- **Note:** This can be added as an enhancement in a future phase
- Product model supports image fields (can be added later)

---

## 📁 Files Created/Modified

### New Files:
```
modules/products/
├── controllers/index.js          # Product controllers
├── services/index.js             # Product service
├── services/variants.js          # Variant service
├── validations/index.js          # Product validations
└── routes/index.js               # Product routes

scripts/seeders/
└── seedProducts.js               # Product seeder
```

### Modified Files:
- `routes/index.js` - Added product routes
- `scripts/seeders/index.js` - Added product seeding
- `package.json` - Added seed:products script

---

## 🔑 API Endpoints

### Product Endpoints

#### GET /api/products
**Description:** List products with pagination and filters
**Auth:** Required
**Query Parameters:**
- `page` - Page number (default: 1)
- `limit` - Items per page (default: 10)
- `search` - Search term (name or SKU)
- `product_type` - Filter by type (FG/RM)
- `track_inventory` - Filter by inventory tracking (true/false)

#### GET /api/products/search
**Description:** Search products by name or SKU
**Auth:** Required
**Query Parameters:**
- `q` or `search` - Search term (required)
- `limit` - Maximum results (default: 20)

#### GET /api/products/:id
**Description:** Get product by ID
**Auth:** Required
**Query Parameters:**
- `include_variants` - Include variants (default: true)

#### POST /api/products
**Description:** Create new product
**Auth:** Required (Manager/Admin only)
**Request Body:**
```json
{
  "name": "Product Name",
  "sku": "PROD-001",
  "product_type": "FG",
  "track_inventory": true,
  "description": "Product description",
  "default_vat_rate": 16,
  "variants": [
    {
      "sku": "PROD-001-V1",
      "attributes": {"size": "M", "color": "Red"}
    }
  ]
}
```

#### PUT /api/products/:id
**Description:** Update product
**Auth:** Required (Manager/Admin only)

#### DELETE /api/products/:id
**Description:** Delete product (returns error - products not deleted for audit)

---

### Variant Endpoints

#### GET /api/products/:id/variants
**Description:** List variants for a product
**Auth:** Required

#### POST /api/products/:id/variants
**Description:** Create variant for a product
**Auth:** Required (Manager/Admin only)
**Request Body:**
```json
{
  "sku": "VARIANT-001",
  "attributes": {"size": "M", "color": "Blue"}
}
```

#### PUT /api/products/:productId/variants/:variantId
**Description:** Update variant
**Auth:** Required (Manager/Admin only)

#### DELETE /api/products/:productId/variants/:variantId
**Description:** Delete variant
**Auth:** Required (Manager/Admin only)

---

## ✅ Acceptance Criteria Status

| Criteria | Status |
|----------|--------|
| Can create/read/update products | ✅ Pass |
| Product variants work correctly | ✅ Pass |
| SKU uniqueness enforced | ✅ Pass |
| Product search returns results | ✅ Pass |
| Product listing paginated | ✅ Pass |

---

## 🔐 Security Features

1. **Authorization:** Create/Update/Delete require Manager/Admin role
2. **Input Validation:** All inputs validated before processing
3. **SKU Uniqueness:** Enforced at both product and variant level
4. **Audit Trail:** All actions logged to SystemLog
5. **Data Integrity:** Products not deleted (kept for audit purposes)

---

## 📋 Phase 2 Checklist

- [x] Product service implementation
- [x] Product variant service
- [x] Product controllers
- [x] Product validations
- [x] Product routes
- [x] Product search/filtering
- [x] Seed data for sample products
- [ ] Image upload (deferred - can be added later)
- [x] Swagger documentation
- [x] System logging
- [x] Error handling

---

## 🚀 Next Steps

**Phase 2 is COMPLETE!** ✅ (except image upload)

Proceed to **Phase 3: Basic Inventory (Quantity-Based)**

The product management system is now fully functional and ready for use.

---

## 📝 Testing Notes

**To test products:**
1. Seed products: `npm run seed:products`
2. List products: `GET /api/products`
3. Search products: `GET /api/products/search?q=laptop`
4. Create product: `POST /api/products` (manager/admin token required)
5. Get product: `GET /api/products/:id`
6. Create variant: `POST /api/products/:id/variants` (manager/admin token required)

**Sample Product Data:**
- 6 sample products created
- Multiple variants for some products
- Mix of FG and RM product types

