docs/technical/TECH-05-API-INTEGRATION.md

# 🔌 API، Protobuf و یکپارچه‌سازی خارجی

> **منابع ادغام‌شده:** `FRONTOFFICE-CMS-API-COMPATIBILITY.md`, `REMAINING-TASKS.md`, `chatika-integration.md`, `payment-gateway.md`, `club-feature-management-services.md`  
> **آخرین بروزرسانی:** اسفند ۱۴۰۴

---

## ۱. معماری ارتباطات

```
┌──────────────────────────────────────────────────────────────────┐
│                    External Services                              │
│  ┌─────────┐ ┌──────────┐ ┌─────────┐ ┌─────────┐              │
│  │ ZarinPal│ │ Kavenegar│ │ DayaLoan│ │ Chatika │              │
│  │ (IPG)   │ │ (SMS)    │ │ (Loan)  │ │ (AI)    │              │
│  └────┬────┘ └────┬─────┘ └────┬────┘ └────┬────┘              │
│       │           │            │            │                    │
│  ┌────▼───────────▼────────────▼────────────▼────┐              │
│  │              CMS Microservice                  │              │
│  │    (gRPC Server + Hangfire + EF Core)          │              │
│  └────────────────┬───────────────────────────────┘              │
│                   │ gRPC (Protobuf v3)                           │
│       ┌───────────┼───────────┐                                  │
│  ┌────▼────┐ ┌────▼────┐                                        │
│  │BackOffice│ │FrontOffice│                                      │
│  │(Blazor  │ │(Blazor   │                                       │
│  │ WASM)   │ │ Server)  │                                       │
│  └─────────┘ └──────────┘                                       │
└──────────────────────────────────────────────────────────────────┘
```

---

## ۲. gRPC Proto Definitions

### ۲.۱ لیست کامل سرویس‌ها

```protobuf
// ===== product.proto =====
service ProductService {
    rpc GetProducts (GetProductsRequest) returns (GetProductsResponse);
    rpc GetProductById (GetProductByIdRequest) returns (ProductMessage);
    rpc CreateProduct (CreateProductRequest) returns (CreateProductResponse);
    rpc UpdateProduct (UpdateProductRequest) returns (UpdateProductResponse);
    rpc DeleteProduct (DeleteProductRequest) returns (Empty);
    rpc GetProductsPaged (GetProductsPagedRequest) returns (GetProductsPagedResponse);
}

// ===== order.proto =====
service OrderService {
    rpc CreateOrder (CreateOrderRequest) returns (CreateOrderResponse);
    rpc GetOrders (GetOrdersRequest) returns (GetOrdersResponse);
    rpc GetOrderById (GetOrderByIdRequest) returns (OrderMessage);
    rpc UpdateOrderStatus (UpdateOrderStatusRequest) returns (Empty);
}

// ===== user.proto =====
service UserService {
    rpc Register (RegisterRequest) returns (AuthResponse);
    rpc Login (LoginRequest) returns (AuthResponse);
    rpc GetProfile (GetProfileRequest) returns (UserProfileMessage);
    rpc UpdateProfile (UpdateProfileRequest) returns (Empty);
    rpc SendOtp (SendOtpRequest) returns (SendOtpResponse);
    rpc VerifyOtp (VerifyOtpRequest) returns (VerifyOtpResponse);
}

// ===== club.proto =====
service ClubService {
    rpc GetNetworkTree (GetNetworkTreeRequest) returns (NetworkTreeResponse);
    rpc GetBalance (GetBalanceRequest) returns (BalanceResponse);
    rpc ReadContract (ReadContractRequest) returns (ContractResponse);
    rpc RequestContractOtp (RequestOtpRequest) returns (OtpResponse);
    rpc VerifyContractOtp (VerifyOtpRequest) returns (VerifyOtpResponse);
    rpc AcceptContract (AcceptContractRequest) returns (AcceptContractResponse);
    rpc GetClubFeatures (GetFeaturesRequest) returns (FeaturesResponse);
}

// ===== payment.proto =====
service PaymentService {
    rpc CreatePayment (CreatePaymentRequest) returns (CreatePaymentResponse);
    rpc VerifyPayment (VerifyPaymentRequest) returns (VerifyPaymentResponse);
    rpc GetPaymentStatus (PaymentStatusRequest) returns (PaymentStatusResponse);
}

// ===== blog.proto =====
service BlogService {
    rpc GetPosts (GetPostsRequest) returns (GetPostsResponse);
    rpc GetPostBySlug (GetPostBySlugRequest) returns (BlogPostMessage);
    rpc CreatePost (CreatePostRequest) returns (CreatePostResponse);
    rpc UpdatePost (UpdatePostRequest) returns (Empty);
    rpc DeletePost (DeletePostRequest) returns (Empty);
}

// ===== inventory.proto =====
service InventoryService {
    rpc GetInventory (GetInventoryRequest) returns (InventoryMessage);
    rpc UpdateStock (UpdateStockRequest) returns (Empty);
    rpc GetAllInventories (GetAllRequest) returns (InventoryListResponse);
}

// ===== sitepage.proto =====
service SitePageService {
    rpc GetPage (GetPageRequest) returns (SitePageMessage);
    rpc SaveSettings (SaveSettingsRequest) returns (Empty);
    rpc GetAllPages (Empty) returns (PageListResponse);
}

// ===== file.proto =====
service FileService {
    rpc Upload (stream UploadRequest) returns (UploadResponse);
    rpc Download (DownloadRequest) returns (stream DownloadResponse);
    rpc Delete (DeleteFileRequest) returns (Empty);
}

// ===== category.proto =====
service CategoryService {
    rpc GetCategories (GetCategoriesRequest) returns (CategoryListResponse);
    rpc CreateCategory (CreateCategoryRequest) returns (CreateCategoryResponse);
    rpc UpdateCategory (UpdateCategoryRequest) returns (Empty);
}

// ===== config.proto =====
service SystemConfigService {
    rpc GetConfig (GetConfigRequest) returns (ConfigResponse);
    rpc UpdateConfig (UpdateConfigRequest) returns (Empty);
    rpc GetAllConfigs (Empty) returns (ConfigListResponse);
}
```

### ۲.۲ Shared Messages

```protobuf
// ===== common.proto =====
message PaginationState {
    int32 skip = 1;
    int32 take = 2;
}

message PaginatedResponse {
    int32 totalCount = 1;
    int32 pageSize = 2;
    int32 currentPage = 3;
}

message Empty {}
```

---

## ۳. External Service Integration

### ۳.۱ ZarinPal (پرداخت)

```csharp
public class ZarinPalService : IPaymentGateway
{
    // Config
    private readonly string _merchantId;
    private readonly bool _isSandbox;
    
    // Endpoints
    const string PAYMENT_URL = "https://api.zarinpal.com/pg/v4/payment/request.json";
    const string VERIFY_URL = "https://api.zarinpal.com/pg/v4/payment/verify.json";
    const string SANDBOX_URL = "https://sandbox.zarinpal.com/pg/v4/payment/request.json";
    
    // Flow
    // 1. CreatePayment → Authority token
    // 2. Redirect → https://www.zarinpal.com/pg/StartPay/{Authority}
    // 3. Callback → VerifyPayment(Authority, Amount)
    // 4. Result → RefID (reference number)
}
```

### ۳.۲ Kavenegar (SMS)

```csharp
public class KavenegarService : ISmsService
{
    // Templates — فقط یک تمپلیت در کد موجود است
    const string OTP_TEMPLATE = "Afrino";  // تنها تمپلیت استفاده‌شده
    // Sender: "1000001110100"
    
    // Rate Limiting
    // ۱ SMS per phone per 60 seconds
    // ۵ SMS per phone per hour
    // ۲۰ SMS per phone per day
    
    public async Task SendOtpAsync(string phone, string code)
    {
        await _api.VerifyLookup(phone, code, OTP_TEMPLATE);
    }
}
```

### ۳.۳ Daya Loan (وام)

```csharp
public class DayaLoanService : ILoanService
{
    // Hangfire job — هر ۲۰ دقیقه (*/20 * * * *)
    // Polly retry: 3 attempts, exponential backoff (2s, 4s, 8s)
    // Mock mode for staging (auto-approve)
    
    public async Task<LoanResult> RequestLoanAsync(Guid userId, decimal amount)
    {
        if (_options.UseMock)
            return LoanResult.Approved(amount);
            
        var response = await _httpClient.PostAsync(
            $"{_baseUrl}/api/loans/request",
            new { UserId = userId, Amount = amount });
        
        return MapResponse(response);
    }
}
```

### ۳.۴ Chatika (AI)

```csharp
public class ChatikaService : IAiChatService
{
    // Hangfire job — هر ۵ دقیقه
    // Polly retry: 3 attempts
    // Only for active club members
    
    public async Task<string> GetResponseAsync(string userMessage)
    {
        var response = await _httpClient.PostAsync(
            $"{_baseUrl}/api/chat",
            new { Message = userMessage });
        
        return response.Content.ReadAsStringAsync();
    }
}
```

---

## ۴. API Compatibility Layer

### ۴.۱ FrontOffice Service Pattern

```csharp
// هر سرویس در FrontOffice یک wrapper بر gRPC client است
public class ProductService : IProductService
{
    private readonly ProductServiceClient _client;
    
    public ProductService(ProductServiceClient client)
    {
        _client = client;
    }
    
    public async Task<ProductListResult> GetProductsPagedAsync(
        int skip, int take, Guid? categoryId = null, string? search = null)
    {
        try
        {
            var request = new GetProductsPagedRequest {
                Pagination = new PaginationState { Skip = skip, Take = take },
                CategoryId = categoryId?.ToString() ?? "",
                SearchTerm = search ?? ""
            };
            
            var response = await _client.GetProductsPagedAsync(request);
            
            return new ProductListResult(
                response.Products.Select(MapToDto).ToList(),
                response.TotalCount);
        }
        catch (RpcException ex) when (ex.StatusCode == StatusCode.Unavailable)
        {
            // CMS is down — show cached data or error
            throw new ServiceUnavailableException("CMS service unavailable");
        }
    }
}
```

### ۴.۲ Error Handling

| gRPC Status | HTTP Equivalent | Handling |
|------------|-----------------|----------|
| `OK` | 200 | Return data |
| `NotFound` | 404 | Show "not found" message |
| `InvalidArgument` | 400 | Show validation errors |
| `Unauthenticated` | 401 | Redirect to login |
| `PermissionDenied` | 403 | Show "access denied" |
| `Unavailable` | 503 | Show "service down" |
| `Internal` | 500 | Show generic error |

---

## ۵. Proto Package Distribution

```
CMS/src/Protos/*.proto
    │
    ▼
pack-protos.sh
    │
    ▼
Foursat.CMSMicroservice.Protobuf.nupkg (v1.0.x)
    │
    ▼
Push to BaGet (http://localhost:5555) or Nexus
    │
    ▼
BackOffice: <PackageReference Include="Foursat.CMSMicroservice.Protobuf" />
FrontOffice: <PackageReference Include="Foursat.CMSMicroservice.Protobuf" />
```

---

## ۶. Remaining Tasks / Integration Gaps

| آیتم | اولویت | وضعیت |
|------|---------|--------|
| Product Bundle API | Medium | ⬜ Proto + Handler needed |
| Manual Payment API | Low | ⬜ Design only |
| SignalR for Chatika | Low | ⬜ Replace polling |
| File upload streaming | Done | ✅ |
| Blog search | Done | ✅ |
| Inventory autocomplete | Done | ✅ |
| Lazy load pagination | Done | ✅ |
| Rate limiting (API level) | Medium | ⬜ |
| API versioning | Low | ⬜ |