# Swagger API Documentation Setup

This document explains how to use and maintain the Swagger API documentation for the Tender Management Backend.

## 📚 Overview

The API documentation is generated using [Swag](https://github.com/swaggo/swag) and served using [echo-swagger](https://github.com/swaggo/echo-swagger). The documentation provides an interactive interface to explore and test all API endpoints.

## 🚀 Quick Start

### 1. Generate Documentation

```bash
# Generate Swagger documentation
make docs

# Or manually
swag init -g cmd/web/main.go -o cmd/web/docs
```

### 2. Start Server with Documentation

```bash
# Build and run with documentation
make run-docs

# Or manually
make build
./bin/web
```

### 3. Access Documentation

Open your browser and navigate to:
- **Swagger UI**: http://localhost:8081/swagger/index.html
- **Health Check**: http://localhost:8081/health

## 📋 Available Endpoints

### 🔐 Authentication
- `POST /api/customers/login` - Customer login
- `POST /api/customers/refresh-token` - Refresh access token

### 👤 Customer Profile (Protected)
- `GET /api/customers/profile` - Get customer profile
- `PUT /api/customers/profile` - Update customer profile
- `PUT /api/customers/change-password` - Change password

### 📱 Device Management (Protected)
- `POST /api/customers/device-token` - Add device token
- `DELETE /api/customers/device-token` - Remove device token

### 👥 Admin Operations (Admin Protected)
- `POST /api/admin/customers/register` - Register new customer
- `GET /api/admin/customers` - List customers
- `GET /api/admin/customers/{id}` - Get customer by ID
- `PUT /api/admin/customers/{id}/status` - Update customer status

## 🛠️ Development

### Adding New Endpoints

1. **Add Swagger Annotations** to your handler functions:

```go
// @Summary Endpoint summary
// @Description Detailed description
// @Tags tag-name
// @Accept json
// @Produce json
// @Security BearerAuth
// @Param param-name param-type param-required "param description"
// @Success 200 {object} response.APIResponse{data=YourResponseType} "Success description"
// @Failure 400 {object} response.APIResponse "Error description"
// @Router /api/endpoint [method]
func (h *Handler) YourHandler(c echo.Context) error {
    // Your handler implementation
}
```

2. **Regenerate Documentation**:

```bash
make docs
```

### Swagger Annotation Examples

#### Basic GET Endpoint
```go
// @Summary Get resource
// @Description Get a resource by ID
// @Tags resources
// @Accept json
// @Produce json
// @Param id path string true "Resource ID"
// @Success 200 {object} response.APIResponse{data=ResourceResponse}
// @Failure 404 {object} response.APIResponse
// @Router /api/resources/{id} [get]
```

#### POST with Request Body
```go
// @Summary Create resource
// @Description Create a new resource
// @Tags resources
// @Accept json
// @Produce json
// @Param resource body CreateResourceForm true "Resource data"
// @Success 201 {object} response.APIResponse{data=ResourceResponse}
// @Failure 400 {object} response.APIResponse
// @Router /api/resources [post]
```

#### Protected Endpoint
```go
// @Summary Protected endpoint
// @Description This endpoint requires authentication
// @Tags resources
// @Accept json
// @Produce json
// @Security BearerAuth
// @Success 200 {object} response.APIResponse
// @Failure 401 {object} response.APIResponse
// @Router /api/protected [get]
```

## 📁 File Structure

```
cmd/web/
├── main.go          # Main application entry point
├── bootstrap.go     # Server initialization
└── docs/           # Generated Swagger documentation
    ├── docs.go     # Generated docs
    ├── swagger.json # OpenAPI specification
    └── swagger.yaml # OpenAPI specification (YAML)

internal/customer/
├── handler.go      # HTTP handlers with Swagger annotations
├── form.go         # Request/response forms
└── ...

pkg/response/
└── response.go     # Standard API response types
```

## 🔧 Configuration

### Swagger Configuration

The main Swagger configuration is in `cmd/web/docs.go`:

```go
// @title Tender Management API
// @version 1.0.0
// @description This is the API documentation for the Tender Management System.
// @host localhost:8081
// @BasePath /api/v1
// @securityDefinitions.apikey BearerAuth
// @in header
// @name Authorization
```

### Server Configuration

The Swagger endpoint is registered in `cmd/web/bootstrap.go`:

```go
// Add Swagger documentation endpoint
e.GET("/swagger/*", echoSwagger.WrapHandler)
```

## 🧪 Testing

### Using the Test Script

```bash
# Run the test script
./test_swagger.sh
```

This script will:
1. Build the application
2. Start the server
3. Display all available endpoints
4. Provide access URLs

### Manual Testing

1. **Start the server**:
   ```bash
   make run-docs
   ```

2. **Access Swagger UI**:
   - Open http://localhost:8081/swagger/index.html
   - Explore and test endpoints interactively

3. **Test Health Check**:
   ```bash
   curl http://localhost:8081/health
   ```

## 📝 Response Types

### Standard Response Structure

All API responses follow this structure:

```json
{
  "success": true,
  "message": "Operation successful",
  "data": {
    // Response data
  },
  "meta": {
    // Pagination metadata (if applicable)
  },
  "error": {
    // Error details (if applicable)
  }
}
```

### Error Response

```json
{
  "success": false,
  "message": "Error message",
  "error": {
    "code": "ERROR_CODE",
    "message": "Detailed error message",
    "details": "Additional details"
  }
}
```

## 🔐 Authentication

### Bearer Token Authentication

Most endpoints require Bearer token authentication:

1. **Login** to get access token:
   ```bash
   curl -X POST http://localhost:8081/api/customers/login \
     -H "Content-Type: application/json" \
     -d '{"email": "user@example.com", "password": "password"}'
   ```

2. **Use the token** in subsequent requests:
   ```bash
   curl -X GET http://localhost:8081/api/customers/profile \
     -H "Authorization: Bearer YOUR_ACCESS_TOKEN"
   ```

## 🚨 Troubleshooting

### Common Issues

1. **Documentation not updating**:
   ```bash
   make clean
   make docs
   make build
   ```

2. **Swagger annotations not recognized**:
   - Ensure annotations are directly above the function
   - Check for syntax errors in annotations
   - Verify import paths are correct

3. **Server won't start**:
   - Check if port 8081 is available
   - Verify MongoDB connection
   - Check configuration files

### Debug Commands

```bash
# Check if swag is installed
swag --version

# Generate docs with verbose output
swag init -g cmd/web/main.go -o cmd/web/docs --parseDependency

# Check generated files
ls -la cmd/web/docs/
```

## 📚 Additional Resources

- [Swag Documentation](https://github.com/swaggo/swag)
- [Echo Swagger](https://github.com/swaggo/echo-swagger)
- [OpenAPI Specification](https://swagger.io/specification/)
- [Swagger UI](https://swagger.io/tools/swagger-ui/)

## 🤝 Contributing

When adding new endpoints:

1. Add comprehensive Swagger annotations
2. Include all possible response codes
3. Provide meaningful examples
4. Test the documentation in Swagger UI
5. Update this documentation if needed

## 📄 License

This documentation is part of the Tender Management Backend project.