✨ Add afdian as OIDC provider

DysonNetwork.Sphere/Auth/AuthController.cs

@@ -97,7 +97,7 @@ public class AuthController(
             .FirstOrDefaultAsync();
         return challenge is null
             ? NotFound("Auth challenge was not found.")
-            : challenge.Account.AuthFactors.Where(e => e.EnabledAt != null).ToList();
+            : challenge.Account.AuthFactors.Where(e => e is { EnabledAt: not null, Trustworthy: >= 1 }).ToList();
     }
 
     [HttpPost("challenge/{id:guid}/factors/{factorId:guid}")]

DysonNetwork.Sphere/Auth/OpenId/AfdianOidcService.cs

@@ -0,0 +1,115 @@
+using System.Net.Http.Json;
+using System.Text.Json;
+using DysonNetwork.Sphere.Storage;
+
+namespace DysonNetwork.Sphere.Auth.OpenId;
+
+public class AfdianOidcService(
+    IConfiguration configuration,
+    IHttpClientFactory httpClientFactory,
+    AppDatabase db,
+    AuthService auth,
+    ICacheService cache
+)
+    : OidcService(configuration, httpClientFactory, db, auth, cache)
+{
+    public override string ProviderName => "Afdian";
+    protected override string DiscoveryEndpoint => ""; // Afdian doesn't have a standard OIDC discovery endpoint
+    protected override string ConfigSectionName => "Afdian";
+
+    public override string GetAuthorizationUrl(string state, string nonce)
+    {
+        var config = GetProviderConfig();
+        var queryParams = new Dictionary<string, string>
+        {
+            { "client_id", config.ClientId },
+            { "redirect_uri", config.RedirectUri },
+            { "response_type", "code" },
+            { "scope", "basic" },
+            { "state", state },
+        };
+
+        var queryString = string.Join("&", queryParams.Select(p => $"{p.Key}={Uri.EscapeDataString(p.Value)}"));
+        return $"https://afdian.com/oauth2/authorize?{queryString}";
+    }
+    
+    protected override Task<OidcDiscoveryDocument?> GetDiscoveryDocumentAsync()
+    {
+        return Task.FromResult(new OidcDiscoveryDocument
+        {
+            AuthorizationEndpoint = "https://afdian.com/oauth2/authorize",
+            TokenEndpoint = "https://afdian.com/api/oauth2/access_token",
+            UserinfoEndpoint = null,
+            JwksUri = null
+        })!;
+    }
+    
+    public override async Task<OidcUserInfo> ProcessCallbackAsync(OidcCallbackData callbackData)
+    {
+        var tokenResponse = await ExchangeCodeForTokensAsync(callbackData.Code);
+        if (tokenResponse?.AccessToken == null)
+        {
+            throw new InvalidOperationException("Failed to obtain access token from Afdian");
+        }
+
+        var userInfo = await GetUserInfoAsync(tokenResponse.AccessToken);
+
+        userInfo.AccessToken = tokenResponse.AccessToken;
+        userInfo.RefreshToken = tokenResponse.RefreshToken;
+
+        return userInfo;
+    }
+
+    protected override async Task<OidcTokenResponse?> ExchangeCodeForTokensAsync(string code,
+        string? codeVerifier = null)
+    {
+        var config = GetProviderConfig();
+        var client = HttpClientFactory.CreateClient();
+
+        var content = new FormUrlEncodedContent(new Dictionary<string, string>
+        {
+            { "client_id", config.ClientId },
+            { "client_secret", config.ClientSecret },
+            { "grant_type", "authorization_code" },
+            { "code", code },
+            { "redirect_uri", config.RedirectUri },
+        });
+
+        var response = await client.PostAsync("https://afdian.com/api/oauth2/access_token", content);
+        response.EnsureSuccessStatusCode();
+
+        return await response.Content.ReadFromJsonAsync<OidcTokenResponse>();
+    }
+
+    private async Task<OidcUserInfo> GetUserInfoAsync(string accessToken)
+    {
+        var client = HttpClientFactory.CreateClient();
+        var request = new HttpRequestMessage(HttpMethod.Get, "https://discord.com/api/users/@me");
+        request.Headers.Add("Authorization", $"Bearer {accessToken}");
+
+        var response = await client.SendAsync(request);
+        response.EnsureSuccessStatusCode();
+
+        var json = await response.Content.ReadAsStringAsync();
+        var discordUser = JsonDocument.Parse(json).RootElement;
+
+        var userId = discordUser.GetProperty("id").GetString() ?? "";
+        var avatar = discordUser.TryGetProperty("avatar", out var avatarElement) ? avatarElement.GetString() : null;
+
+        return new OidcUserInfo
+        {
+            UserId = userId,
+            Email = (discordUser.TryGetProperty("email", out var emailElement) ? emailElement.GetString() : null) ?? "",
+            EmailVerified = discordUser.TryGetProperty("verified", out var verifiedElement) &&
+                            verifiedElement.GetBoolean(),
+            DisplayName = (discordUser.TryGetProperty("global_name", out var globalNameElement)
+                ? globalNameElement.GetString()
+                : null) ?? "",
+            PreferredUsername = discordUser.GetProperty("username").GetString() ?? "",
+            ProfilePictureUrl = !string.IsNullOrEmpty(avatar)
+                ? $"https://cdn.discordapp.com/avatars/{userId}/{avatar}.png"
+                : "",
+            Provider = ProviderName
+        };
+    }
+}

DysonNetwork.Sphere/Auth/OpenId/OidcController.cs

@@ -120,6 +120,7 @@ public class OidcController(
             "microsoft" => serviceProvider.GetRequiredService<MicrosoftOidcService>(),
             "discord" => serviceProvider.GetRequiredService<DiscordOidcService>(),
             "github" => serviceProvider.GetRequiredService<GitHubOidcService>(),
+            "afdian" => serviceProvider.GetRequiredService<AfdianOidcService>(),
             _ => throw new ArgumentException($"Unsupported provider: {provider}")
         };
     }

DysonNetwork.Sphere/Startup/ServiceCollectionExtensions.cs

@@ -53,11 +53,13 @@ public static class ServiceCollectionExtensions
         services.AddScoped<OidcService, GitHubOidcService>();
         services.AddScoped<OidcService, MicrosoftOidcService>();
         services.AddScoped<OidcService, DiscordOidcService>();
+        services.AddScoped<OidcService, AfdianOidcService>();
         services.AddScoped<GoogleOidcService>();
         services.AddScoped<AppleOidcService>();
         services.AddScoped<GitHubOidcService>();
         services.AddScoped<MicrosoftOidcService>();
         services.AddScoped<DiscordOidcService>();
+        services.AddScoped<AfdianOidcService>();
 
         services.AddControllers().AddJsonOptions(options =>
         {