feat(chat): add /guilds/{id} and /guilds/@me endpoints

Foxchat.Chat/Controllers/Api/GuildsController.cs

@@ -5,6 +5,7 @@ using Foxchat.Chat.Services;
 using Foxchat.Core.Models;
 using Foxchat.Core.Models.Http;
 using Microsoft.AspNetCore.Mvc;
+using Microsoft.EntityFrameworkCore;
 using ApiError = Foxchat.Core.ApiError;
 
 namespace Foxchat.Chat.Controllers.Api;
@@ -16,10 +17,9 @@ public class GuildsController(ILogger logger, ChatContext db, UserResolverServic
     [HttpPost]
     public async Task<IActionResult> CreateGuild([FromBody] GuildsApi.CreateGuildRequest req)
     {
-        var (instance, sig) = HttpContext.GetSignatureOrThrow();
+        var (instance, _, userId) = HttpContext.GetSignatureWithUser();
-        if (sig.UserId == null) throw new ApiError.IncomingFederationError("This endpoint requires a user ID.");
 
-        var user = await userResolverService.ResolveUserAsync(instance, sig.UserId);
+        var user = await userResolverService.ResolveUserAsync(instance, userId);
 
         var guild = new Guild
         {
@@ -44,4 +44,41 @@ public class GuildsController(ILogger logger, ChatContext db, UserResolverServic
             [new Channels.PartialChannel(defaultChannel.Id.ToString(), defaultChannel.Name)])
         );
     }
+
+    [HttpGet("{id}")]
+    public async Task<IActionResult> GetGuild(Ulid id)
+    {
+        var (instance, _, userId) = HttpContext.GetSignatureWithUser();
+        var guild = await db.Guilds
+            .Include(g => g.Channels)
+            .FirstOrDefaultAsync(g =>
+                g.Id == id && g.Users.Any(u => u.RemoteUserId == userId && u.InstanceId == instance.Id));
+        if (guild == null) throw new ApiError.NotFound("Guild not found");
+
+        return Ok(new Guilds.Guild(
+            guild.Id.ToString(),
+            guild.Name,
+            [guild.OwnerId.ToString()],
+            guild.Channels.Select(c => new Channels.PartialChannel(c.Id.ToString(), c.Name))
+        ));
+    }
+
+    [HttpGet("@me")]
+    public async Task<IActionResult> GetUserGuilds()
+    {
+        var (instance, _, userId) = HttpContext.GetSignatureWithUser();
+        var guilds = await db.Guilds
+            .Include(g => g.Channels)
+            .Where(g => g.Users.Any(u => u.RemoteUserId == userId && u.InstanceId == instance.Id))
+            .ToListAsync();
+
+        var guildResponses = guilds.Select(g => new Guilds.Guild(
+            g.Id.ToString(),
+            g.Name,
+            [g.OwnerId.ToString()],
+            g.Channels.Select(c => new Channels.PartialChannel(c.Id.ToString(), c.Name))
+        ));
+
+        return Ok(guildResponses);
+    }
 }

Foxchat.Chat/Middleware/ServerAuthenticationMiddleware.cs

@@ -76,4 +76,11 @@ public static class HttpContextExtensions
 
         return ((IdentityInstance, SignatureData))obj!;
     }
+
+    public static (IdentityInstance, SignatureData, string) GetSignatureWithUser(this HttpContext ctx)
+    {
+        var (instance, sig) = ctx.GetSignatureOrThrow();
+        if (sig.UserId == null) throw new ApiError.IncomingFederationError("This endpoint requires a user ID.");
+        return (instance, sig, sig.UserId);
+    }
 }