feat(backend): start authentication controllers

Foxnouns.Backend/Services/AuthService.cs

@@ -3,6 +3,7 @@ using Foxnouns.Backend.Database;
 using Foxnouns.Backend.Database.Models;
 using Foxnouns.Backend.Utils;
 using Microsoft.AspNetCore.Identity;
+using Microsoft.EntityFrameworkCore;
 using NodaTime;
 
 namespace Foxnouns.Backend.Services;
@@ -30,6 +31,23 @@ public class AuthService(ILogger logger, DatabaseContext db, ISnowflakeGenerator
         return user;
     }
 
+    public async Task<User> AuthenticateUserAsync(string email, string password)
+    {
+        var user = await db.Users.FirstOrDefaultAsync(u => u.AuthMethods.Any(a => a.AuthType == AuthType.Email && a.RemoteId == email));
+        if (user == null) throw new ApiError.NotFound("No user with that email address found, or password is incorrect");
+        
+        var pwResult = await Task.Run(() => _passwordHasher.VerifyHashedPassword(user, user.Password!, password));
+        if (pwResult == PasswordVerificationResult.Failed)
+            throw new ApiError.NotFound("No user with that email address found, or password is incorrect");
+        if (pwResult == PasswordVerificationResult.SuccessRehashNeeded)
+        {
+            user.Password = await Task.Run(() => _passwordHasher.HashPassword(user, password));
+            await db.SaveChangesAsync();
+        }
+
+        return user;
+    }
+
     public (string, Token) GenerateToken(User user, Application application, string[] scopes, Instant expires)
     {
         if (!OauthUtils.ValidateScopes(application, scopes))

Foxnouns.Backend/Services/KeyCacheService.cs

@@ -0,0 +1,51 @@
+using Foxnouns.Backend.Database;
+using Foxnouns.Backend.Database.Models;
+using Foxnouns.Backend.Utils;
+using Microsoft.EntityFrameworkCore;
+using NodaTime;
+
+namespace Foxnouns.Backend.Services;
+
+public class KeyCacheService(DatabaseContext db, IClock clock, ILogger logger)
+{
+    public Task SetKeyAsync(string key, string value, Duration expireAfter) =>
+        db.SetKeyAsync(key, value, clock.GetCurrentInstant() + expireAfter);
+
+    public async Task SetKeyAsync(string key, string value, Instant expires)
+    {
+        db.TemporaryKeys.Add(new TemporaryKey
+        {
+            Expires = expires,
+            Key = key,
+            Value = value,
+        });
+        await db.SaveChangesAsync();
+    }
+
+    public async Task<string?> GetKeyAsync(string key, bool delete = false)
+    {
+        var value = await db.TemporaryKeys.FirstOrDefaultAsync(k => k.Key == key);
+        if (value == null) return null;
+
+        if (delete)
+        {
+            await db.TemporaryKeys.Where(k => k.Key == key).ExecuteDeleteAsync();
+            await db.SaveChangesAsync();
+        }
+
+        return value.Value;
+    }
+
+    public async Task DeleteExpiredKeysAsync()
+    {
+        var count = await db.TemporaryKeys.Where(k => k.Expires < clock.GetCurrentInstant()).ExecuteDeleteAsync();
+        if (count != 0) logger.Information("Removed {Count} expired keys from the database", count);
+    }
+
+    public async Task<string> GenerateAuthStateAsync()
+    {
+        var state = OauthUtils.RandomToken();
+        await SetKeyAsync($"oauth_state:{state}", "", Duration.FromMinutes(10));
+        return state;
+    }
+}

Foxnouns.Backend/Services/UserRendererService.cs

@@ -7,7 +7,7 @@ namespace Foxnouns.Backend.Services;
 
 public class UserRendererService(DatabaseContext db, MemberRendererService memberRendererService)
 {
-    public async Task<object> RenderUserAsync(User user, User? selfUser = null, bool renderMembers = true)
+    public async Task<UserResponse> RenderUserAsync(User user, User? selfUser = null, bool renderMembers = true)
     {
         renderMembers = renderMembers && (!user.ListHidden || selfUser?.Id == user.Id);