fix: migrate to IDbContextFactory and remove direct AppDbContext from DI (#11)

Reviewed-on: #11
Co-authored-by: Marek Jasiński <jasins.marek@gmail.com>
Co-committed-by: Marek Jasiński <jasins.marek@gmail.com>

src/NexusReader.Infrastructure/Identity/TokenLimitHandler.cs

@@ -2,7 +2,8 @@ using System.Security.Claims;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Identity;
 using NexusReader.Domain.Entities;
-using NexusReader.Infrastructure.Persistence;
+using NexusReader.Data.Persistence;
+using Microsoft.EntityFrameworkCore;
 
 namespace NexusReader.Infrastructure.Identity;
 
@@ -11,12 +12,12 @@ namespace NexusReader.Infrastructure.Identity;
 /// </summary>
 public class TokenLimitHandler : AuthorizationHandler<TokenLimitRequirement>
 {
-    private readonly AppDbContext _dbContext;
+    private readonly IDbContextFactory<AppDbContext> _dbContextFactory;
     private readonly UserManager<NexusUser> _userManager;
 
-    public TokenLimitHandler(AppDbContext dbContext, UserManager<NexusUser> userManager)
+    public TokenLimitHandler(IDbContextFactory<AppDbContext> dbContextFactory, UserManager<NexusUser> userManager)
     {
-        _dbContext = dbContext;
+        _dbContextFactory = dbContextFactory;
         _userManager = userManager;
     }
 
@@ -30,14 +31,18 @@ public class TokenLimitHandler : AuthorizationHandler<TokenLimitRequirement>
             return;
         }
 
-        var user = await _userManager.FindByIdAsync(userId);
+        using var db = _dbContextFactory.CreateDbContext();
+        var user = await db.Users
+            .Include(u => u.SubscriptionPlan)
+            .FirstOrDefaultAsync(u => u.Id == userId);
+
         if (user == null)
         {
             return;
         }
 
-        // Check if user has available tokens
-        if (user.AITokensUsed < user.AITokenLimit)
+        // Check if user has available tokens or unlimited plan
+        if (user.SubscriptionPlan?.IsUnlimitedTokens == true || user.AITokensUsed < user.AITokenLimit)
         {
             context.Succeed(requirement);
         }