add: loyalty reward system

Backend/Features/Borrowing/BorrowingService.cs

@@ -1,5 +1,6 @@
 using Database.Models;
 using Microsoft.EntityFrameworkCore;
+using Backend.Features.Loyalty;
 
 namespace Backend.Features.Borrowings
 {
@@ -14,11 +15,13 @@ namespace Backend.Features.Borrowings
     public class BorrowingService : IBorrowingService
     {
         private readonly LibraryManagementContext _context;
+        private readonly ILoyaltyService _loyaltyService;
         private const decimal FinePerDay = 500;
 
-        public BorrowingService(LibraryManagementContext context)
+        public BorrowingService(LibraryManagementContext context, ILoyaltyService loyaltyService)
         {
             _context = context;
+            _loyaltyService = loyaltyService;
         }
 
         public async Task<BorrowingDto> BorrowBookAsync(int userId, int bookId)
@@ -86,6 +89,21 @@ namespace Backend.Features.Borrowings
             await _context.Entry(borrowing).Reference(b => b.Book).LoadAsync();
             await _context.Entry(borrowing).Reference(b => b.User).LoadAsync();
 
+            // Loyalty Integration: Send BORROW event
+            string externalUserId = userId.ToString();
+            string userMobile = borrowing.User?.PhoneNumber ?? "0000000000";
+            string userEmail = borrowing.User?.Email ?? "No Email";
+            
+            await _loyaltyService.ProcessEventAsync(
+                externalUserId: externalUserId,
+                eventKey: "BORROW",
+                eventValue: 0,
+                referenceId: $"BRW-{borrowing.Id}",
+                description: $"Borrowed Book: {borrowing.Book?.Title}",
+                email: userEmail,
+                mobile: userMobile
+            );
+
             return MapToDto(borrowing);
         }
 

Backend/Features/Loyalty/LoyaltyController.cs

@@ -0,0 +1,38 @@
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using System.Security.Claims;
+using System.Threading.Tasks;
+
+namespace Backend.Features.Loyalty
+{
+    [ApiController]
+    [Route("api/[controller]")]
+    [Authorize]
+    public class LoyaltyController : ControllerBase
+    {
+        private readonly ILoyaltyService _loyaltyService;
+
+        public LoyaltyController(ILoyaltyService loyaltyService)
+        {
+            _loyaltyService = loyaltyService;
+        }
+
+        [HttpGet("my-account")]
+        public async Task<IActionResult> GetMyAccount()
+        {
+            var userIdStr = User.FindFirst(ClaimTypes.NameIdentifier)?.Value;
+            if (string.IsNullOrEmpty(userIdStr))
+            {
+                return Unauthorized();
+            }
+
+            var account = await _loyaltyService.GetUserAccountAsync(userIdStr);
+            if (account == null)
+            {
+                return NotFound("Loyalty account not found.");
+            }
+
+            return Ok(account);
+        }
+    }
+}

Backend/Features/Loyalty/LoyaltyService.cs

@@ -0,0 +1,116 @@
+using System;
+using System.Net.Http;
+using System.Net.Http.Json;
+using System.Threading.Tasks;
+using Microsoft.Extensions.Logging;
+
+namespace Backend.Features.Loyalty
+{
+    public interface ILoyaltyService
+    {
+        Task<bool> RegisterUserAsync(string externalUserId, string email, string mobile);
+        Task<bool> ProcessEventAsync(string externalUserId, string eventKey, double eventValue, string referenceId, string description, string email, string mobile);
+        Task<AccountLookupResponse?> GetUserAccountAsync(string externalUserId);
+    }
+
+    public class LoyaltyService : ILoyaltyService
+    {
+        private readonly HttpClient _httpClient;
+        private readonly ILogger<LoyaltyService> _logger;
+        private const string SystemId = "THS-LMS";
+
+        public LoyaltyService(HttpClient httpClient, ILogger<LoyaltyService> logger)
+        {
+            _httpClient = httpClient;
+            _logger = logger;
+            _httpClient.DefaultRequestHeaders.Add("x-system-id", SystemId);
+        }
+
+        public async Task<bool> RegisterUserAsync(string externalUserId, string email, string mobile)
+        {
+            try
+            {
+                var payload = new
+                {
+                    systemId = SystemId,
+                    externalUserId = externalUserId,
+                    email = email,
+                    mobile = mobile,
+                    tier = "Member" // Default
+                };
+
+                var response = await _httpClient.PostAsJsonAsync("/api/v1/accounts", payload);
+                if (!response.IsSuccessStatusCode)
+                {
+                    var error = await response.Content.ReadAsStringAsync();
+                    _logger.LogWarning($"Failed to register user in loyalty system: {error}");
+                    return false;
+                }
+                return true;
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Error registering user in loyalty system.");
+                return false;
+            }
+        }
+
+        public async Task<bool> ProcessEventAsync(string externalUserId, string eventKey, double eventValue, string referenceId, string description, string email, string mobile)
+        {
+            try
+            {
+                var payload = new
+                {
+                    externalUserId = externalUserId,
+                    eventKey = eventKey,
+                    eventValue = eventValue,
+                    referenceId = referenceId,
+                    description = description,
+                    email = email,
+                    mobile = mobile
+                };
+
+                var response = await _httpClient.PostAsJsonAsync("/api/v1/events/process", payload);
+                if (!response.IsSuccessStatusCode)
+                {
+                    var error = await response.Content.ReadAsStringAsync();
+                    _logger.LogWarning($"Failed to process loyalty event {eventKey} for user {externalUserId}: {error}");
+                    return false;
+                }
+                return true;
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, $"Error processing loyalty event {eventKey}.");
+                return false;
+            }
+        }
+
+        public async Task<AccountLookupResponse?> GetUserAccountAsync(string externalUserId)
+        {
+            try
+            {
+                var response = await _httpClient.GetAsync($"/api/v1/accounts/lookup/{SystemId}/{externalUserId}");
+                if (response.IsSuccessStatusCode)
+                {
+                    return await response.Content.ReadFromJsonAsync<AccountLookupResponse>();
+                }
+                return null;
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, $"Error fetching loyalty account for user {externalUserId}.");
+                return null;
+            }
+        }
+    }
+
+    public class AccountLookupResponse
+    {
+        public string Id { get; set; } = string.Empty;
+        public string ExternalUserId { get; set; } = string.Empty;
+        public double CurrentBalance { get; set; }
+        public string Tier { get; set; } = string.Empty;
+        public double LifetimePoints { get; set; }
+    }
+}

Backend/Features/Subscriptions/SubscriptionService.cs

@@ -1,5 +1,6 @@
 using Database.Models;
 using Microsoft.EntityFrameworkCore;
+using Backend.Features.Loyalty;
 
 namespace Backend.Features.Subscriptions
 {
@@ -13,10 +14,12 @@ namespace Backend.Features.Subscriptions
     public class SubscriptionService : ISubscriptionService
     {
         private readonly LibraryManagementContext _context;
+        private readonly ILoyaltyService _loyaltyService;
 
-        public SubscriptionService(LibraryManagementContext context)
+        public SubscriptionService(LibraryManagementContext context, ILoyaltyService loyaltyService)
         {
             _context = context;
+            _loyaltyService = loyaltyService;
         }
 
         public async Task<IEnumerable<MembershipDto>> GetMembershipsAsync()
@@ -75,6 +78,22 @@ namespace Backend.Features.Subscriptions
 
             // Explicitly load the membership data for the DTO mapping
             await _context.Entry(subscription).Reference(s => s.Membership).LoadAsync();
+            await _context.Entry(subscription).Reference(s => s.User).LoadAsync();
+
+            // Loyalty Integration: Send SUBSCRIBE event
+            string externalUserId = userId.ToString();
+            string userMobile = subscription.User?.PhoneNumber ?? "0000000000";
+            string userEmail = subscription.User?.Email ?? "No Email";
+
+            await _loyaltyService.ProcessEventAsync(
+                externalUserId: externalUserId,
+                eventKey: "SUBSCRIBE",
+                eventValue: (double)membership.Price,
+                referenceId: $"SUB-{subscription.Id}",
+                description: $"Purchased Membership: {membership.Type}",
+                email: userEmail,
+                mobile: userMobile
+            );
 
             return MapToDto(subscription);
         }

Backend/Features/Users/UserService.cs

@@ -1,6 +1,7 @@
 using Database.Models;
 using Microsoft.EntityFrameworkCore;
 using Backend.Features.Subscriptions;
+using Backend.Features.Loyalty;
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -22,11 +23,13 @@ namespace Backend.Features.Users
     {
         private readonly LibraryManagementContext _context;
         private readonly ISubscriptionService _subscriptionService;
+        private readonly ILoyaltyService _loyaltyService;
 
-        public UserService(LibraryManagementContext context, ISubscriptionService subscriptionService)
+        public UserService(LibraryManagementContext context, ISubscriptionService subscriptionService, ILoyaltyService loyaltyService)
         {
             _context = context;
             _subscriptionService = subscriptionService;
+            _loyaltyService = loyaltyService;
         }
 
         public async Task<IEnumerable<UserDto>> GetAllUsersAsync()
@@ -69,6 +72,20 @@ namespace Backend.Features.Users
                 await _subscriptionService.SubscribeUserAsync(user.Id, 3); // 3 is "Basic Yearly"
             }
 
+            // Loyalty Integration: Register the new user and process SIGNUP event
+            string externalUserId = user.Id.ToString();
+            string userMobile = user.PhoneNumber ?? "0000000000";
+            await _loyaltyService.RegisterUserAsync(externalUserId, user.Email, userMobile);
+            await _loyaltyService.ProcessEventAsync(
+                externalUserId: externalUserId,
+                eventKey: "SIGNUP",
+                eventValue: 0,
+                referenceId: $"USR-{user.Id}",
+                description: "New User Registration",
+                email: user.Email,
+                mobile: userMobile
+            );
+
             return MapToDto(user);
         }
 

Backend/Program.cs

@@ -10,9 +10,11 @@ using Microsoft.OpenApi.Models;
 using Backend.Features.Subscriptions;
 using Backend.Features.Categories;
 using Backend.Features.Borrowings;
+using Backend.Features.Loyalty;
 
 var builder = WebApplication.CreateBuilder(args);
 
+
 builder.Services.AddControllers();
 builder.Services.AddAuthorization();
 builder.Services.AddEndpointsApiExplorer();
@@ -55,6 +57,12 @@ builder.Services.AddScoped<ISubscriptionService, SubscriptionService>();
 builder.Services.AddScoped<ICategoryService, CategoryService>();
 builder.Services.AddScoped<IBorrowingService, BorrowingService>();
 
+// Register Loyalty API Client
+builder.Services.AddHttpClient<ILoyaltyService, LoyaltyService>(client =>
+{
+    client.BaseAddress = new Uri("http://150.95.88.91:4100");
+});
+
 // Configure JWT Authentication
 var key = Encoding.ASCII.GetBytes(builder.Configuration["Jwt:Secret"] ?? "YourSuperSecretKeyForLibraryManagementSystem_AtLeast32CharsLong");
 builder.Services.AddAuthentication(x =>

Frontend/Controllers/HomeController.cs

@@ -24,6 +24,14 @@ namespace Frontend.Controllers
                 var borrowings = await _apiClient.GetMyBorrowingsAsync();
                 var members = await _apiClient.GetUsersAsync();
                 
+                // Fetch loyalty points (if user is logged in)
+                if (User.Identity?.IsAuthenticated == true)
+                {
+                    var loyaltyAccount = await _apiClient.GetMyLoyaltyAccountAsync();
+                    ViewBag.LoyaltyPoints = loyaltyAccount?.CurrentBalance ?? 0;
+                    ViewBag.LoyaltyTier = loyaltyAccount?.Tier ?? "Member";
+                }
+                
                 ViewBag.TotalBooks = books.Count();
                 ViewBag.ActiveLoans = borrowings.Count(b => !b.ReturnDate.HasValue);
                 ViewBag.OverdueLoans = borrowings.Count(b => !b.ReturnDate.HasValue && b.DueDate < DateTime.UtcNow);
@@ -37,9 +45,10 @@ namespace Frontend.Controllers
                 // Set default values if API fails
                 ViewBag.TotalBooks = 0;
                 ViewBag.ActiveLoans = 0;
-                ViewBag.OverdueLoans = 0;
                 ViewBag.TotalMembers = 0;
                 ViewBag.RecentBooks = Enumerable.Empty<Frontend.Models.Dtos.BookDto>();
+                ViewBag.LoyaltyPoints = 0;
+                ViewBag.LoyaltyTier = "Member";
             }
 
             return View();

Frontend/Frontend.csproj

@@ -7,3 +7,4 @@
   </PropertyGroup>
 
 </Project>
+ 

Frontend/Models/Dtos/LibraryDtos.cs

@@ -124,6 +124,16 @@ namespace Frontend.Models.Dtos
         public int MembershipId { get; set; }
     }
 
+    // Loyalty DTOs
+    public class LoyaltyAccountDto
+    {
+        public string Id { get; set; } = string.Empty;
+        public string ExternalUserId { get; set; } = string.Empty;
+        public double CurrentBalance { get; set; }
+        public string Tier { get; set; } = string.Empty;
+        public double LifetimePoints { get; set; }
+    }
+
     // User DTOs
     public class UserDto
     {

Frontend/Services/LibraryApiClient.cs

@@ -158,6 +158,15 @@ namespace Frontend.Services
         }
         #endregion
 
+        #region Loyalty
+        public async Task<LoyaltyAccountDto?> GetMyLoyaltyAccountAsync()
+        {
+            try {
+                return await _httpClient.GetFromJsonAsync<LoyaltyAccountDto>("api/loyalty/my-account");
+            } catch { return null; }
+        }
+        #endregion
+
         #region Users
         public async Task<IEnumerable<UserDto>> GetUsersAsync()
         {

Frontend/Views/Home/Index.cshtml

@@ -7,6 +7,30 @@
     <p class="text-slate-500 font-medium">Here's what's happening with the library today.</p>
 </div>
 
+@if (User.Identity?.IsAuthenticated == true)
+{
+    <!-- Loyalty Banner -->
+    <div class="bg-gradient-to-r from-amber-500 to-amber-700 rounded-2xl p-6 mb-10 text-white shadow-lg relative overflow-hidden group">
+        <div class="relative z-10 flex items-center justify-between">
+            <div>
+                <p class="text-amber-100 text-sm font-bold uppercase tracking-widest mb-1">Your Loyalty Status</p>
+                <div class="flex items-baseline gap-3">
+                    <h2 class="text-4xl font-extrabold">@ViewBag.LoyaltyPoints</h2>
+                    <span class="text-amber-200 font-medium tracking-wide">Points</span>
+                </div>
+            </div>
+            <div class="text-right">
+                <div class="inline-flex items-center gap-2 bg-black/20 backdrop-blur-sm px-4 py-2 rounded-full border border-white/10 shadow-inner">
+                    <svg class="w-5 h-5 text-amber-200" fill="none" stroke="currentColor" viewBox="0 0 24 24"><path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M5 3v4M3 5h4M6 17v4m-2-2h4m5-16l2.286 6.857L21 12l-5.714 2.143L13 21l-2.286-6.857L5 12l5.714-2.143L13 3z"></path></svg>
+                    <span class="font-bold text-lg">@ViewBag.LoyaltyTier</span>
+                </div>
+            </div>
+        </div>
+        <!-- Decorative Background -->
+        <div class="absolute -right-10 -top-10 w-48 h-48 bg-white/10 rounded-full blur-2xl transform group-hover:scale-110 transition-transform duration-700"></div>
+    </div>
+}
+
 <!-- Stats Grid -->
 <div class="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-4 gap-6 mb-12">
     <div class="card p-6 flex flex-col gap-3 group hover:border-slate-300">

LibraryManagement.slnx

@@ -1,5 +1,5 @@
 <Solution>
+  <Project Path="Backend/Backend.csproj" Id="82e311b1-ce76-4235-9d5f-0d06a942d038" />
   <Project Path="Database/Database.csproj" Id="1ec23dc7-355d-4456-a503-cfd0fb81cd5c" />
   <Project Path="Frontend/Frontend.csproj" Id="824d7fed-4fd3-41c5-8c5e-acd458ccbcdb" />
-  <Project Path="Backend/Backend.csproj" Id="82e311b1-ce76-4235-9d5f-0d06a942d038" />
 </Solution>