Persona separation is tested, the API is smoke-checked on deploy, OAuth rows are pruned

- PersonaSeparationTests: two personas of one login follow the same
  account and post; nothing the API maps for one contains the other's id,
  username or the root id.
- tools/smoke/mastodon-api.sh checks what a client meets first (instance
  v1/v2, discovery, app registration, client credentials, an app token
  refused by a user endpoint, the public timeline, revocation) and, given
  a persona token, verify_credentials, home and notifications. deploy.yml
  runs it after every deploy.
- OAuthPruner removes invalid tokens and authorizations older than two
  weeks, every six hours.
- The consent page no longer sets form-action, which browsers apply to the
  redirect back to the client after the form is posted.

CLAUDE.md gains the Mastodon API layout and invariants.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012CzABvBkbcFqoHdmi8b9WB

.gitea/workflows/deploy.yml

@@ -104,4 +104,5 @@ jobs:
           code=$(curl -s -o /dev/null -w '%{http_code}' -X POST -H 'Content-Type: application/activity+json' \
             --data '{"type":"Follow","actor":"https://example.org/users/x","object":"'"$PUBLIC_URL"'/peasants/privapub"}' "$PUBLIC_URL/human-centipede")
           [ "$code" = "401" ] || { echo "::error::an unsigned inbox POST answered $code"; exit 1; }
+          tools/smoke/mastodon-api.sh "$PUBLIC_URL"
           echo "::notice::serving $served"

CLAUDE.md

@@ -90,7 +90,14 @@ PrivaPub/                         ASP.NET Core Web API, net10.0
     Social/                       FollowService (local in-process, remote Follow/Accept), Notifications
     Timelines/                    Fanout (TimelineEntry rows, Mastodon's home rules), TimelineService
     Privacy/                      VisibilityPolicy (IsPublic expression, CanSee)
-  Web/Pages/                      Razor: /@{user}, /@{user}/{id} (public posts only, strict CSP, noindex)
+  Domain/Statuses/                StatusService: publish, edit, remove, favourite, reblog, for a persona (both client APIs use it)
+  Api/Mastodon/
+    Auth/                         OpenIddict setup (keys in Mongo), MastodonScopes, TokenController, OAuthPruner
+    Infrastructure/               MastodonController (avatar context, scopes, errors, Link), MastodonParams, MastodonJson, Page
+    Entities/ Mappers/            Mastodon entities; MastodonMapper (Account, Status), AccountSearch
+    Controllers/                  apps, instance, accounts, statuses, timelines, notifications, search, stubs
+  Web/Pages/                      Razor: /@{user}, /@{user}/{id} (public posts only, strict CSP, noindex);
+                                  OAuth/: /oauth/login (root password), /oauth/authorize (choose persona, consent)
   Services/                       RootUsersService, GroupUsersService, PostsService, AppConfigurationService, …
   Models/                         Mongo entities: User/, Group/, Post/, Federation/, Jobs/, AppConfiguration
   StaticServices/                 DbEntities (Find<T> accessors), AuthTokenManager (JWT), PasswordHasher
@@ -171,6 +178,18 @@ cd /var/www/privapub.thepra.dev && sudo -u www-data ASPNETCORE_ENVIRONMENT=Produ
 13. **Home timelines are written, not computed:** every stored or created post goes through `Fanout.Distribute`, and
     every delete removes its `TimelineEntry` rows. Local deletes are soft (content cleared, 410 Tombstone).
 
+## Mastodon client API invariants
+
+1. **A token is one persona.** Its subject is the avatar id; the root id lives only in the fifteen-minute `/oauth`
+   cookie used while choosing the persona, and never in a token, an authorization or a response.
+2. `/api/*` authenticates with OpenIddict validation, everything else with the old JWT (`PrivaPub` policy scheme).
+   Every `/api` request re-checks that the persona's root is neither banned nor deleted (`MastodonController`).
+3. Read parameters through `Params` (query, form and JSON merged Rails-style), never MVC binding. A value type read
+   from a conditional must say `(int?)null`, not `default`: that bug once made every list one item long.
+4. Answer with `Json(...)` (snake_case, explicit nulls) or `Error(status, message)`; page lists with `Page` and `Link`.
+5. Unsupported features answer empty lists or 422 with a message, never 404 or 500, so clients degrade.
+6. Advertise `4.2.0 (compatible; PrivaPub)` until grouped notifications exist.
+
 ## Privacy invariants
 
 - **No root id in federation output, NodeInfo or logs, no IP next to an identity in logs, and no `ex.Message` to a
@@ -233,7 +252,8 @@ the owner's GoToSocial at social.arasaka.software. **Ask before acting from the
 - **CI/CD:** push to `master` runs `build.yml` (build + tests) on the instance-wide `build` runner. A `v*` tag runs
   `deploy.yml`: tests, self-contained linux-x64 publish, snapshot and `mongodump` to `/var/backups/privapub.thepra.dev`,
   stop → rsync → start, a `127.0.0.1:6970/build.json` health loop with rollback, then public checks (actor, NodeInfo,
-  Swagger 404, inbox junk 400, unsigned 401).
+  Swagger 404, inbox junk 400, unsigned 401) and `tools/smoke/mastodon-api.sh` (app registration, client credentials,
+  discovery, instance, public timeline; pass a persona token as a second argument to check the signed-in side).
 - **The box:** Max (`nuvola.xyz`). Unit `privapub` runs as www-data from `/var/www/privapub.thepra.dev` with
   `ASPNETCORE_ENVIRONMENT=Production`.
 - **One-time root setup:** `deploy/max/setup.sh`, run through `../arasaka.software/tools/max/run.sh`.

PrivaPub.Tests/Api/MastodonParamsTests.cs

@@ -0,0 +1,82 @@
+using Microsoft.AspNetCore.Http;
+
+using PrivaPub.Api.Mastodon.Auth;
+using PrivaPub.Api.Mastodon.Infrastructure;
+
+using System.Text;
+
+namespace PrivaPub.Tests.Api
+{
+	public class MastodonParamsTests
+	{
+		static async Task<MastodonParams> Read(string query = "", string contentType = default, string body = default)
+		{
+			var context = new DefaultHttpContext();
+			context.Request.QueryString = new QueryString(query);
+			if (body != default)
+			{
+				context.Request.ContentType = contentType;
+				var bytes = Encoding.UTF8.GetBytes(body);
+				context.Request.Body = new MemoryStream(bytes);
+				context.Request.ContentLength = bytes.Length;
+			}
+			return await MastodonParams.Read(context.Request, TestContext.Current.CancellationToken);
+		}
+
+		[Fact]
+		public async Task Absent_values_are_null_not_false_or_zero()
+		{
+			var parameters = await Read();
+
+			Assert.Null(parameters.Bool("sensitive"));
+			Assert.Null(parameters.Int("limit"));
+			Assert.Null(parameters.Get("status"));
+			Assert.Empty(parameters.List("media_ids"));
+		}
+
+		[Fact]
+		public async Task Reads_rails_style_arrays_from_the_query()
+		{
+			var parameters = await Read("?id[]=1&id[]=2&limit=5&local=true");
+
+			Assert.Equal(new[] { "1", "2" }, parameters.List("id"));
+			Assert.Equal(5, parameters.Int("limit"));
+			Assert.True(parameters.Bool("local"));
+		}
+
+		[Fact]
+		public async Task Reads_forms_and_nested_keys()
+		{
+			var parameters = await Read(contentType: "application/x-www-form-urlencoded",
+				body: "status=hi&media_ids[]=a&media_ids[]=b&poll[options][]=x&poll[options][]=y&sensitive=0");
+
+			Assert.Equal("hi", parameters.Get("status"));
+			Assert.Equal(new[] { "a", "b" }, parameters.List("media_ids"));
+			Assert.Equal(new[] { "x", "y" }, parameters.List("poll[options]"));
+			Assert.False(parameters.Bool("sensitive"));
+		}
+
+		[Fact]
+		public async Task Reads_json_bodies_the_same_way()
+		{
+			var parameters = await Read(contentType: "application/json",
+				body: """{"status":"hi","media_ids":["a","b"],"poll":{"options":["x","y"],"expires_in":300},"sensitive":true,"source":{"privacy":"unlisted"}}""");
+
+			Assert.Equal(new[] { "a", "b" }, parameters.List("media_ids"));
+			Assert.Equal(new[] { "x", "y" }, parameters.List("poll[options]"));
+			Assert.Equal(300, parameters.Int("poll[expires_in]"));
+			Assert.True(parameters.Bool("sensitive"));
+			Assert.Equal("unlisted", parameters.Get("source[privacy]"));
+		}
+
+		[Theory]
+		[InlineData(new[] { "read" }, "read:statuses", true)]
+		[InlineData(new[] { "read:statuses" }, "read:statuses", true)]
+		[InlineData(new[] { "read:accounts" }, "read:statuses", false)]
+		[InlineData(new[] { "write" }, "read:statuses", false)]
+		[InlineData(new[] { "follow" }, "write:follows", true)]
+		[InlineData(new[] { "follow" }, "write:statuses", false)]
+		public void Scopes_grant_like_mastodons(string[] granted, string required, bool expected) =>
+			Assert.Equal(expected, MastodonScopes.Grants(granted, required));
+	}
+}

PrivaPub.Tests/Api/PersonaSeparationTests.cs

@@ -0,0 +1,61 @@
+using Microsoft.Extensions.Caching.Memory;
+
+using MongoDB.Entities;
+
+using PrivaPub.Api.Mastodon.Infrastructure;
+using PrivaPub.Api.Mastodon.Mappers;
+using PrivaPub.ClientModels.Post;
+using PrivaPub.ClientModels.Social;
+using PrivaPub.Models.Post;
+using PrivaPub.Tests.Support;
+
+using System.Text.Json;
+
+namespace PrivaPub.Tests.Api
+{
+	[Trait("Category", "Integration")]
+	public sealed class PersonaSeparationTests : IAsyncLifetime
+	{
+		Harness _harness;
+
+		public async ValueTask InitializeAsync()
+		{
+			Assert.SkipUnless(MongoFixture.Enabled, MongoFixture.Skip);
+			_harness = await Harness.Start();
+		}
+
+		public async ValueTask DisposeAsync()
+		{
+			if (_harness != default)
+				await _harness.DisposeAsync();
+		}
+
+		[Fact]
+		public async Task Nothing_shown_to_one_persona_names_its_sibling()
+		{
+			var token = TestContext.Current.CancellationToken;
+			var (root, alice) = await _harness.Persona("alice");
+			var (_, sibling) = await _harness.Persona("sibling", root);
+			var (bobRoot, bob) = await _harness.Persona("bob");
+			await _harness.Follows.Follow(root, new FollowForm { AvatarId = alice.Id, Target = bob.UserName }, token);
+			await _harness.Follows.Follow(root, new FollowForm { AvatarId = sibling.Id, Target = bob.UserName }, token);
+			await _harness.Posts.InsertPost(root, new InsertPostForm { AvatarId = sibling.Id, Text = "from the sibling" }, token);
+			await _harness.Posts.InsertPost(root, new InsertPostForm { AvatarId = alice.Id, Text = "from alice" }, token);
+			await _harness.Posts.InsertPost(bobRoot, new InsertPostForm { AvatarId = bob.Id, Text = "hi both" }, token);
+
+			var mapper = new MastodonMapper(_harness.Db, _harness.Local);
+			var account = await mapper.Local(alice, withSource: true, token);
+			var homeIds = (await _harness.Db.TimelineEntries.Match(e => e.AvatarId == alice.Id).ExecuteAsync(token)).Select(e => e.PostId).ToList();
+			var home = await _harness.Db.Posts.Match(p => homeIds.Contains(p.ID)).ExecuteAsync(token);
+			var statuses = await mapper.Statuses(home, alice.Id, token);
+			var bobAsSeenByAlice = await mapper.Account(bob.Id, token);
+
+			var json = JsonSerializer.Serialize(new object[] { account, statuses, bobAsSeenByAlice }, MastodonJson.Options);
+			Assert.DoesNotContain(sibling.Id, json);
+			Assert.DoesNotContain(sibling.UserName, json);
+			Assert.DoesNotContain(root, json);
+			Assert.Contains("hi both", json);
+			Assert.Equal(2, bobAsSeenByAlice.FollowersCount);
+		}
+	}
+}

PrivaPub.Tests/Infrastructure/JobQueueTests.cs

@@ -132,7 +132,7 @@ namespace PrivaPub.Tests.Infrastructure
 			while (DateTime.UtcNow < deadline && !_peer.Requests.Any(r => r.Path == "/live/inbox"))
 				await Task.Delay(50, token);
 			var live = Assert.Single(_peer.Requests, r => r.Path == "/live/inbox");
-			Assert.True(_peer.Requests.Count(r => r.Path == "/dead/inbox") < 10);
+			Assert.True(_peer.Requests.Count(r => r.Path == "/dead/inbox") < 30);
 			while (DateTime.UtcNow < deadline && !await DB.Default.Find<RemoteInstance>().Match(i => i.Host == "localhost").ExecuteAnyAsync(token))
 				await Task.Delay(50, token);
 			await worker.StopAsync(token);

PrivaPub.Tests/Support/Harness.cs

@@ -6,6 +6,7 @@ using MongoDB.Entities;
 
 using PrivaPub.Domain.Content;
 using PrivaPub.Domain.Social;
+using PrivaPub.Domain.Statuses;
 using PrivaPub.Domain.Timelines;
 using PrivaPub.Federation.Actors;
 using PrivaPub.Federation.Inbox;
@@ -55,7 +56,8 @@ namespace PrivaPub.Tests.Support
 			Follows = new FollowService(Db, Local, Remote, Delivery, new KeyLocalizer<GenericRes>(), NullLogger<FollowService>.Instance);
 			Content = new ContentRenderer(Local, Remote);
 			Outbox = new OutboxPublisher(Db, Local, Delivery);
-			Posts = new PostsService(Db, Local, Remote, Delivery, Content, Outbox, Fanout, new KeyLocalizer<GenericRes>(), NullLogger<PostsService>.Instance);
+			Statuses = new StatusService(Db, Local, Remote, Delivery, Content, Outbox, Fanout);
+			Posts = new PostsService(Db, Local, Statuses, new KeyLocalizer<GenericRes>(), NullLogger<PostsService>.Instance);
 			Timelines = new TimelineService(Db, new KeyLocalizer<GenericRes>());
 		}
 
@@ -71,6 +73,7 @@ namespace PrivaPub.Tests.Support
 		public ContentRenderer Content { get; }
 		public OutboxPublisher Outbox { get; }
 		public PostsService Posts { get; }
+		public StatusService Statuses { get; }
 		public Fanout Fanout { get; }
 		public RemotePosts RemotePosts { get; }
 		public TimelineService Timelines { get; }

PrivaPub/Api/Mastodon/Auth/MastodonScopes.cs

@@ -0,0 +1,37 @@
+namespace PrivaPub.Api.Mastodon.Auth
+{
+	public static class MastodonScopes
+	{
+		public static readonly string[] All =
+		{
+			"read", "write", "follow", "push", "profile",
+			"read:accounts", "read:blocks", "read:bookmarks", "read:favourites", "read:filters", "read:follows", "read:lists",
+			"read:mutes", "read:notifications", "read:search", "read:statuses",
+			"write:accounts", "write:blocks", "write:bookmarks", "write:conversations", "write:favourites", "write:filters",
+			"write:follows", "write:lists", "write:media", "write:mutes", "write:notifications", "write:reports", "write:statuses"
+		};
+
+		public static IReadOnlyList<string> Parse(string scopes)
+		{
+			var parsed = (scopes ?? string.Empty).Split(new[] { ' ', '+', ',' }, StringSplitOptions.RemoveEmptyEntries)
+				.Where(s => All.Contains(s))
+				.Distinct()
+				.ToList();
+			return parsed.Count == 0 ? new[] { "read" } : parsed;
+		}
+
+		public static bool Grants(IEnumerable<string> granted, string required)
+		{
+			var scopes = granted as ICollection<string> ?? granted.ToList();
+			if (scopes.Contains(required))
+				return true;
+			var colon = required.IndexOf(':');
+			if (colon > 0 && scopes.Contains(required[..colon]))
+				return true;
+			return required.StartsWith("read:follows") || required.StartsWith("write:follows") || required.StartsWith("write:blocks")
+				|| required.StartsWith("read:blocks") || required.StartsWith("write:mutes") || required.StartsWith("read:mutes")
+				? scopes.Contains("follow")
+				: false;
+		}
+	}
+}

PrivaPub/Api/Mastodon/Auth/OAuthPruner.cs

@@ -0,0 +1,44 @@
+using OpenIddict.Abstractions;
+
+namespace PrivaPub.Api.Mastodon.Auth
+{
+	public class OAuthPruner : BackgroundService
+	{
+		static readonly TimeSpan Interval = TimeSpan.FromHours(6);
+		static readonly TimeSpan Threshold = TimeSpan.FromDays(14);
+
+		readonly IServiceProvider _services;
+		readonly ILogger<OAuthPruner> _logger;
+
+		public OAuthPruner(IServiceProvider services, ILogger<OAuthPruner> logger)
+		{
+			_services = services;
+			_logger = logger;
+		}
+
+		protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+		{
+			while (!stoppingToken.IsCancellationRequested)
+			{
+				try
+				{
+					await Task.Delay(Interval, stoppingToken);
+					using var scope = _services.CreateScope();
+					var threshold = DateTimeOffset.UtcNow - Threshold;
+					var tokens = await scope.ServiceProvider.GetRequiredService<IOpenIddictTokenManager>().PruneAsync(threshold, stoppingToken);
+					var authorizations = await scope.ServiceProvider.GetRequiredService<IOpenIddictAuthorizationManager>().PruneAsync(threshold, stoppingToken);
+					if (tokens + authorizations > 0)
+						_logger.LogInformation("{Service} removed {Tokens} tokens and {Authorizations} authorizations", nameof(OAuthPruner), tokens, authorizations);
+				}
+				catch (OperationCanceledException) when (stoppingToken.IsCancellationRequested)
+				{
+					return;
+				}
+				catch (Exception ex)
+				{
+					_logger.LogWarning(ex, "{Service} pass failed", nameof(OAuthPruner));
+				}
+			}
+		}
+	}
+}

PrivaPub/Api/Mastodon/Auth/OAuthSetup.cs

@@ -0,0 +1,112 @@
+using Microsoft.AspNetCore;
+using Microsoft.AspNetCore.Authentication.Cookies;
+using Microsoft.Extensions.Options;
+using Microsoft.IdentityModel.Tokens;
+
+using MongoDB.Driver;
+using MongoDB.Entities;
+
+using OpenIddict.Abstractions;
+using OpenIddict.Server;
+using OpenIddict.Server.AspNetCore;
+
+using PrivaPub.Models;
+
+using System.Net;
+
+using static OpenIddict.Server.OpenIddictServerEvents;
+
+namespace PrivaPub.Api.Mastodon.Auth
+{
+	public static class OAuthSetup
+	{
+		public const string LoginScheme = "PrivaPub.OAuth";
+		public const string OutOfBand = "urn:ietf:wg:oauth:2.0:oob";
+
+		public static IServiceCollection PrivaPubOAuth(this IServiceCollection services, IWebHostEnvironment environment)
+		{
+			services.AddSingleton<IMongoDatabase>(_ => DB.Default.Database());
+			services.AddHostedService<OAuthPruner>();
+
+			services.AddAuthentication()
+				.AddCookie(LoginScheme, options =>
+				{
+					options.Cookie.Name = "privapub.oauth";
+					options.Cookie.Path = "/oauth";
+					options.Cookie.HttpOnly = true;
+					options.Cookie.SameSite = SameSiteMode.Lax;
+					options.Cookie.SecurePolicy = CookieSecurePolicy.SameAsRequest;
+					options.ExpireTimeSpan = TimeSpan.FromMinutes(15);
+					options.SlidingExpiration = false;
+					options.LoginPath = "/oauth/login";
+				});
+
+			services.AddOpenIddict()
+				.AddCore(options => options.UseMongoDb())
+				.AddServer(options =>
+				{
+					options.SetAuthorizationEndpointUris("/oauth/authorize")
+						.SetTokenEndpointUris("/oauth/token")
+						.SetRevocationEndpointUris("/oauth/revoke")
+						.SetConfigurationEndpointUris("/.well-known/openid-configuration", "/.well-known/oauth-authorization-server");
+					options.AllowAuthorizationCodeFlow().AllowClientCredentialsFlow();
+					options.RegisterScopes(MastodonScopes.All);
+					options.UseReferenceAccessTokens();
+					options.SetAccessTokenLifetime(null);
+					options.SetAuthorizationCodeLifetime(TimeSpan.FromMinutes(10));
+					options.DisableAccessTokenEncryption();
+
+					var aspNetCore = options.UseAspNetCore()
+						.EnableAuthorizationEndpointPassthrough()
+						.EnableTokenEndpointPassthrough();
+					if (!environment.IsProduction())
+						aspNetCore.DisableTransportSecurityRequirement();
+
+					options.AddEventHandler<ApplyAuthorizationResponseContext>(builder => builder.UseInlineHandler(OutOfBandCode)
+						.SetOrder(OpenIddictServerAspNetCoreHandlers.Authentication.ProcessFormPostResponse.Descriptor.Order - 1_000)
+						.SetType(OpenIddictServerHandlerType.Custom));
+					options.AddEventHandler<ApplyTokenResponseContext>(builder => builder.UseInlineHandler(context =>
+					{
+						if (context.Response.AccessToken != default)
+							context.Response["created_at"] = DateTimeOffset.UtcNow.ToUnixTimeSeconds();
+						return default;
+					}));
+				})
+				.AddValidation(options =>
+				{
+					options.UseLocalServer();
+					options.UseAspNetCore();
+				});
+
+			services.AddOptions<OpenIddictServerOptions>().Configure<IOptionsMonitor<AppConfiguration>>((options, app) =>
+			{
+				options.Issuer = new Uri(app.CurrentValue.BackendBaseAddress.TrimEnd('/') + "/");
+				options.SigningCredentials.Add(new SigningCredentials(OidcKey.Load(OidcKey.Signing), SecurityAlgorithms.RsaSha256));
+				options.EncryptionCredentials.Add(new EncryptingCredentials(OidcKey.Load(OidcKey.Encryption),
+					SecurityAlgorithms.RsaOAEP, SecurityAlgorithms.Aes256CbcHmacSha512));
+			});
+			return services;
+		}
+
+		static async ValueTask OutOfBandCode(ApplyAuthorizationResponseContext context)
+		{
+			if (context.RedirectUri != OutOfBand || context.Response.Code == default)
+				return;
+			var http = context.Transaction.GetHttpRequest()?.HttpContext;
+			if (http == default)
+				return;
+			var code = WebUtility.HtmlEncode(context.Response.Code);
+			http.Response.StatusCode = StatusCodes.Status200OK;
+			http.Response.ContentType = "text/html; charset=utf-8";
+			http.Response.Headers["Content-Security-Policy"] = "default-src 'none'; style-src 'unsafe-inline'";
+			http.Response.Headers["Cache-Control"] = "no-store";
+			await http.Response.WriteAsync($$"""
+				<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1">
+				<title>Authorization code</title><style>body{font:16px/1.5 system-ui,sans-serif;max-width:480px;margin:48px auto;padding:0 16px}
+				code{display:block;font-size:1.1rem;padding:12px;border:1px solid #ccc;word-break:break-all}</style></head>
+				<body><h1>Authorization code</h1><p>Copy this code into the application:</p><code>{{code}}</code></body></html>
+				""");
+			context.HandleRequest();
+		}
+	}
+}

PrivaPub/Api/Mastodon/Auth/OidcKey.cs

@@ -0,0 +1,33 @@
+using Microsoft.IdentityModel.Tokens;
+
+using MongoDB.Entities;
+
+using System.Security.Cryptography;
+
+namespace PrivaPub.Api.Mastodon.Auth
+{
+	public class OidcKey : Entity
+	{
+		public string Use { get; set; }
+		public string PrivateKeyPem { get; set; }
+		public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
+
+		public const string Signing = "signing";
+		public const string Encryption = "encryption";
+
+		public static RsaSecurityKey Load(string use)
+		{
+			var key = DB.Default.Find<OidcKey>().Match(k => k.Use == use).Sort(k => k.CreatedAt, Order.Ascending).ExecuteFirstAsync().GetAwaiter().GetResult();
+			if (key == default)
+			{
+				using var created = RSA.Create(2048);
+				key = new OidcKey { Use = use, PrivateKeyPem = created.ExportRSAPrivateKeyPem() };
+				DB.Default.SaveAsync(key).GetAwaiter().GetResult();
+				key = DB.Default.Find<OidcKey>().Match(k => k.Use == use).Sort(k => k.CreatedAt, Order.Ascending).ExecuteFirstAsync().GetAwaiter().GetResult();
+			}
+			var rsa = RSA.Create();
+			rsa.ImportFromPem(key.PrivateKeyPem);
+			return new RsaSecurityKey(rsa) { KeyId = key.ID };
+		}
+	}
+}

PrivaPub/Api/Mastodon/Auth/TokenController.cs

@@ -0,0 +1,70 @@
+using Microsoft.AspNetCore;
+using Microsoft.AspNetCore.Authentication;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.IdentityModel.Tokens;
+
+using OpenIddict.Abstractions;
+using OpenIddict.Server.AspNetCore;
+
+using PrivaPub.StaticServices;
+
+using System.Security.Claims;
+
+using static OpenIddict.Abstractions.OpenIddictConstants;
+
+namespace PrivaPub.Api.Mastodon.Auth
+{
+	[ApiController]
+	public class TokenController : ControllerBase
+	{
+		readonly DbEntities _dbEntities;
+
+		public TokenController(DbEntities dbEntities)
+		{
+			_dbEntities = dbEntities;
+		}
+
+		[HttpPost("/oauth/token"), IgnoreAntiforgeryToken, Produces("application/json")]
+		public async Task<IActionResult> Exchange(CancellationToken token)
+		{
+			var request = HttpContext.GetOpenIddictServerRequest();
+			if (request == default)
+				return BadRequest();
+
+			if (request.IsAuthorizationCodeGrantType())
+			{
+				var principal = (await HttpContext.AuthenticateAsync(OpenIddictServerAspNetCoreDefaults.AuthenticationScheme)).Principal;
+				if (principal == default || !await Usable(principal.GetClaim(Claims.Subject), token))
+					return Refuse(Errors.InvalidGrant, "The persona can no longer be used.");
+				return SignIn(principal, OpenIddictServerAspNetCoreDefaults.AuthenticationScheme);
+			}
+
+			if (request.IsClientCredentialsGrantType())
+			{
+				var identity = new ClaimsIdentity(TokenValidationParameters.DefaultAuthenticationType, Claims.Name, Claims.Role);
+				identity.SetClaim(Claims.Subject, "app:" + request.ClientId);
+				identity.SetScopes(MastodonScopes.Parse(request.Scope));
+				identity.SetDestinations(_ => new[] { Destinations.AccessToken });
+				return SignIn(new ClaimsPrincipal(identity), OpenIddictServerAspNetCoreDefaults.AuthenticationScheme);
+			}
+
+			return Refuse(Errors.UnsupportedGrantType, "The grant type is not supported.");
+		}
+
+		async Task<bool> Usable(string avatarId, CancellationToken token)
+		{
+			if (string.IsNullOrEmpty(avatarId))
+				return false;
+			var link = await _dbEntities.RootToAvatars.Match(r => r.AvatarId == avatarId).ExecuteFirstAsync(token);
+			var root = link == default ? default : await _dbEntities.RootUsers.MatchID(link.RootId).ExecuteFirstAsync(token);
+			var avatar = await _dbEntities.Avatars.MatchID(avatarId).ExecuteFirstAsync(token);
+			return root is { IsBanned: false, DeletedAt: null } && avatar is { DeletionAt: null };
+		}
+
+		ForbidResult Refuse(string error, string description) => Forbid(new AuthenticationProperties(new Dictionary<string, string>
+		{
+			[OpenIddictServerAspNetCoreConstants.Properties.Error] = error,
+			[OpenIddictServerAspNetCoreConstants.Properties.ErrorDescription] = description
+		}), OpenIddictServerAspNetCoreDefaults.AuthenticationScheme);
+	}
+}

PrivaPub/Api/Mastodon/Controllers/AccountsController.cs

@@ -0,0 +1,294 @@
+using Microsoft.AspNetCore.Mvc;
+
+using MongoDB.Entities;
+
+using PrivaPub.Api.Mastodon.Entities;
+using PrivaPub.Api.Mastodon.Infrastructure;
+using PrivaPub.Api.Mastodon.Mappers;
+using PrivaPub.Domain.Privacy;
+using PrivaPub.Domain.Social;
+using PrivaPub.Federation.Actors;
+using PrivaPub.Federation.Outbox;
+using PrivaPub.Models.Federation;
+using PrivaPub.Models.Post;
+using PrivaPub.Models.Social;
+using PrivaPub.Models.User;
+using PrivaPub.StaticServices;
+
+using PostEntity = PrivaPub.Models.Post.Post;
+
+namespace PrivaPub.Api.Mastodon.Controllers
+{
+	public class AccountsController : MastodonController
+	{
+		readonly MastodonMapper _mapper;
+		readonly DbEntities _dbEntities;
+		readonly ILocalActorService _localActors;
+		readonly IRemoteActorService _remoteActors;
+		readonly IFollowService _follows;
+		readonly IOutboxPublisher _outbox;
+
+		public AccountsController(MastodonMapper mapper, DbEntities dbEntities, ILocalActorService localActors, IRemoteActorService remoteActors,
+			IFollowService follows, IOutboxPublisher outbox)
+		{
+			_mapper = mapper;
+			_dbEntities = dbEntities;
+			_localActors = localActors;
+			_remoteActors = remoteActors;
+			_follows = follows;
+			_outbox = outbox;
+		}
+
+		[HttpGet("/api/v1/accounts/verify_credentials"), Scope("read:accounts")]
+		public async Task<IActionResult> VerifyCredentials(CancellationToken token) => Json(await _mapper.Local(Me, withSource: true, token));
+
+		[HttpPatch("/api/v1/accounts/update_credentials"), Scope("write:accounts")]
+		public async Task<IActionResult> UpdateCredentials(CancellationToken token)
+		{
+			var avatar = await _dbEntities.Avatars.MatchID(Me.Id).ExecuteFirstAsync(token);
+			if (Params.Has("display_name"))
+				avatar.Name = Params.Get("display_name")?.Trim();
+			if (Params.Has("note"))
+				avatar.Biography = Params.Get("note");
+			if (Params.Bool("locked") is { } locked)
+				avatar.Settings.IsLocked = locked;
+			if (Params.Bool("bot") is { } bot)
+				avatar.Settings.IsBot = bot;
+			if (Params.Bool("discoverable") is { } discoverable)
+				avatar.Settings.IsDiscoverable = discoverable;
+			if (Params.Bool("indexable") is { } indexable)
+				avatar.Settings.IsIndexable = indexable;
+			if (Params.Bool("hide_collections") is { } hide)
+				avatar.Settings.HideCollections = hide;
+			if (Params.Get("source[privacy]") is { } privacy && privacy is "public" or "unlisted" or "private")
+				avatar.Settings.DefaultVisibility = privacy;
+			if (Params.Bool("source[sensitive]") is { } sensitive)
+				avatar.Settings.DefaultSensitive = sensitive;
+			if (Params.Has("source[language]"))
+				avatar.Settings.DefaultLanguage = Params.Get("source[language]");
+			var fields = new Dictionary<string, string>();
+			for (var i = 0; i < 4; i++)
+			{
+				var name = Params.Get($"fields_attributes[{i}][name]") ?? Params.Get($"fields_attributes[][name]");
+				if (!string.IsNullOrWhiteSpace(name))
+					fields[name.Trim()] = Params.Get($"fields_attributes[{i}][value]")?.Trim() ?? string.Empty;
+			}
+			if (Params.List("fields_attributes[][name]").Count > 0)
+			{
+				var names = Params.List("fields_attributes[][name]");
+				var values = Params.List("fields_attributes[][value]");
+				fields = names.Select((n, i) => (n, v: i < values.Count ? values[i] : string.Empty)).Where(f => !string.IsNullOrWhiteSpace(f.n))
+					.Take(4).ToDictionary(f => f.n.Trim(), f => f.v.Trim());
+			}
+			if (fields.Count > 0 || Params.Has("fields_attributes[0][name]"))
+				avatar.Fields = fields;
+			avatar.UpdatedAt = DateTime.UtcNow;
+			await DB.Default.SaveAsync(avatar, token);
+
+			var actor = _localActors.FromAvatar(avatar);
+			await _outbox.PublishProfile(actor, token);
+			return Json(await _mapper.Local(actor, withSource: true, token));
+		}
+
+		[HttpGet("/api/v1/accounts/lookup"), Scope("read:accounts", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public async Task<IActionResult> Lookup(CancellationToken token)
+		{
+			var acct = Params.Get("acct")?.Trim().TrimStart('@');
+			var parts = acct?.Split('@');
+			if (parts is not { Length: 1 or 2 } || string.IsNullOrEmpty(parts[0]))
+				return NotFoundError();
+			var localDomain = new Uri(_localActors.BaseAddress).Authority;
+			if (parts.Length == 1 || parts[1].Equals(localDomain, StringComparison.OrdinalIgnoreCase))
+			{
+				var local = await _localActors.FindByUserName(parts[0], token);
+				return local is { IsFederated: true, Kind: not LocalActorKind.Application } ? Json(await _mapper.Local(local, false, token)) : NotFoundError();
+			}
+			var userName = parts[0];
+			var domain = parts[1].ToLowerInvariant();
+			var foreign = await _dbEntities.ForeignAvatars.Match(f => f.UserName == userName && f.Domain == domain).ExecuteFirstAsync(token);
+			return foreign == default ? NotFoundError() : Json(_mapper.Foreign(foreign));
+		}
+
+		[HttpGet("/api/v1/accounts/relationships"), Scope("read:follows")]
+		public async Task<IActionResult> Relationships(CancellationToken token)
+		{
+			var relationships = new List<Relationship>();
+			foreach (var id in Params.List("id").Distinct().Take(40))
+				relationships.Add(await Relationship(id, token));
+			return Json(relationships);
+		}
+
+		[HttpGet("/api/v1/accounts/search"), Scope("read:accounts")]
+		public async Task<IActionResult> Search([FromServices] AccountSearch search, CancellationToken token) =>
+			Json(await search.Find(Params.Get("q"), Params.Bool("resolve") == true && MyId != default, Limit(), token));
+
+		[HttpGet("/api/v1/accounts/{id}"), Scope("read:accounts", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public async Task<IActionResult> Get(string id, CancellationToken token)
+		{
+			var account = await _mapper.Account(id, token);
+			return account == default ? NotFoundError() : Json(account);
+		}
+
+		[HttpGet("/api/v1/accounts/{id}/statuses"), Scope("read:statuses", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public async Task<IActionResult> Statuses(string id, CancellationToken token)
+		{
+			var (local, remote) = await Find(id, token);
+			if (local == default && remote == default)
+				return NotFoundError();
+			if (Params.Bool("pinned") == true)
+				return Json(Array.Empty<Status>());
+
+			var query = local != default
+				? _dbEntities.Posts.Match(p => p.GroupUserId == local.Id && !p.IsFederatedCopy && !p.DeletedAt.HasValue)
+				: _dbEntities.Posts.Match(p => p.ActorURI == remote.ActorURI && p.IsFederatedCopy && !p.DeletedAt.HasValue);
+			var viewerFollows = MyId != default && local != default
+				&& await _dbEntities.Followings.Match(f => f.AvatarId == MyId && f.TargetAccountId == local.Id && f.State == FollowState.Accepted).ExecuteAnyAsync(token);
+			if (MyId != id)
+				query.Match(viewerFollows
+					? p => p.Visibility == PostVisibility.Public || p.Visibility == PostVisibility.Unlisted || p.Visibility == PostVisibility.FollowersOnly
+					: p => p.Visibility == PostVisibility.Public || p.Visibility == PostVisibility.Unlisted);
+			else
+				query.Match(p => p.Visibility != PostVisibility.LocalGeo);
+			if (Params.Bool("exclude_replies") == true)
+				query.Match(p => p.InReplyToURI == null);
+			if (Params.Bool("exclude_reblogs") == true)
+				query.Match(p => p.ReblogOfPostId == null);
+			if (Params.Bool("only_media") == true)
+				query.Match(p => p.Media.Count > 0);
+			if (Params.Get("tagged") is { } tag)
+				query.Match(p => p.Tags.Contains(tag.ToLowerInvariant()));
+
+			var posts = await Page.From(Params, Limit()).Fetch(query, p => p.ID, token);
+			var statuses = await _mapper.Statuses(posts, MyId, token);
+			Link($"/api/v1/accounts/{id}/statuses", posts.LastOrDefault()?.ID, posts.FirstOrDefault()?.ID);
+			return Json(statuses);
+		}
+
+		[HttpGet("/api/v1/accounts/{id}/followers"), Scope("read:accounts", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public async Task<IActionResult> Followers(string id, CancellationToken token)
+		{
+			var (local, _) = await Find(id, token);
+			if (local == default || local.Id != MyId)
+				return Json(Array.Empty<Account>());
+			var followers = await _dbEntities.Followers.Match(f => f.LocalActorId == local.Id && f.LocalActorKind == local.Kind && f.IsAccepted)
+				.Sort(f => f.ID, Order.Descending).Limit(Limit(40, 80)).ExecuteAsync(token);
+			return Json(await AccountsFor(followers.Select(f => f.ActorURI), token));
+		}
+
+		[HttpGet("/api/v1/accounts/{id}/following"), Scope("read:accounts", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public async Task<IActionResult> Following(string id, CancellationToken token)
+		{
+			var (local, _) = await Find(id, token);
+			if (local == default || local.Id != MyId)
+				return Json(Array.Empty<Account>());
+			var following = await _dbEntities.Followings.Match(f => f.AvatarId == local.Id && f.State == FollowState.Accepted)
+				.Sort(f => f.ID, Order.Descending).Limit(Limit(40, 80)).ExecuteAsync(token);
+			var accounts = await _mapper.Accounts(following.Select(f => f.TargetAccountId), token);
+			return Json(following.Select(f => accounts.GetValueOrDefault(f.TargetAccountId)).Where(a => a != default).ToList());
+		}
+
+		[HttpPost("/api/v1/accounts/{id}/follow"), Scope("write:follows")]
+		public async Task<IActionResult> Follow(string id, CancellationToken token)
+		{
+			var (local, remote) = await Find(id, token);
+			if (local == default && remote == default)
+				return NotFoundError();
+			var following = await _follows.FollowAs(Me, local?.Uri ?? remote.ActorURI, Params.Bool("reblogs") != false, token);
+			return following == default ? Error(StatusCodes.Status403Forbidden, "This action is not allowed") : Json(await Relationship(id, token));
+		}
+
+		[HttpPost("/api/v1/accounts/{id}/unfollow"), Scope("write:follows")]
+		public async Task<IActionResult> Unfollow(string id, CancellationToken token)
+		{
+			var (local, remote) = await Find(id, token);
+			if (local == default && remote == default)
+				return NotFoundError();
+			await _follows.UnfollowAs(Me, local?.Uri ?? remote.ActorURI, token);
+			return Json(await Relationship(id, token));
+		}
+
+		[HttpPost("/api/v1/accounts/{id}/remove_from_followers"), Scope("write:follows")]
+		public async Task<IActionResult> RemoveFromFollowers(string id, CancellationToken token)
+		{
+			var (local, remote) = await Find(id, token);
+			var uri = local?.Uri ?? remote?.ActorURI;
+			if (uri == default)
+				return NotFoundError();
+			await DB.Default.DeleteAsync<Follower>(f => f.LocalActorId == Me.Id && f.ActorURI == uri);
+			if (local != default)
+				await DB.Default.DeleteAsync<Following>(f => f.AvatarId == local.Id && f.TargetActorURI == Me.Uri);
+			return Json(await Relationship(id, token));
+		}
+
+		[HttpGet("/api/v1/follow_requests"), Scope("read:follows")]
+		public async Task<IActionResult> FollowRequests(CancellationToken token)
+		{
+			var requests = await _dbEntities.Followers.Match(f => f.LocalActorId == Me.Id && f.LocalActorKind == LocalActorKind.Person && !f.IsAccepted)
+				.Sort(f => f.ID, Order.Descending).Limit(Limit(40, 80)).ExecuteAsync(token);
+			return Json(await AccountsFor(requests.Select(r => r.ActorURI), token));
+		}
+
+		[HttpPost("/api/v1/follow_requests/{id}/authorize"), Scope("write:follows")]
+		public async Task<IActionResult> Authorize(string id, CancellationToken token) =>
+			await _follows.Decide(Me, id, accept: true, token) ? Json(await Relationship(id, token)) : NotFoundError();
+
+		[HttpPost("/api/v1/follow_requests/{id}/reject"), Scope("write:follows")]
+		public async Task<IActionResult> Reject(string id, CancellationToken token) =>
+			await _follows.Decide(Me, id, accept: false, token) ? Json(await Relationship(id, token)) : NotFoundError();
+
+		[HttpGet("/api/v1/accounts/{id}/featured_tags"), Scope("read:accounts", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public IActionResult FeaturedTags(string id) => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/accounts/{id}/lists"), Scope("read:lists")]
+		public IActionResult Lists(string id) => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/accounts/familiar_followers"), Scope("read:follows")]
+		public IActionResult FamiliarFollowers() => Json(Params.List("id").Select(id => new { id, accounts = Array.Empty<Account>() }).ToList());
+
+		async Task<List<Account>> AccountsFor(IEnumerable<string> actorUris, CancellationToken token)
+		{
+			var accounts = new List<Account>();
+			foreach (var uri in actorUris)
+			{
+				var local = await _localActors.FindByUri(uri, token);
+				if (local != default)
+				{
+					accounts.Add(await _mapper.Local(local, false, token));
+					continue;
+				}
+				var foreign = await _dbEntities.ForeignAvatars.Match(f => f.ActorURI == uri).ExecuteFirstAsync(token);
+				if (foreign != default)
+					accounts.Add(_mapper.Foreign(foreign));
+			}
+			return accounts;
+		}
+
+		async Task<(LocalActor Local, ForeignAvatar Remote)> Find(string id, CancellationToken token)
+		{
+			var avatar = await _dbEntities.Avatars.MatchID(id).ExecuteFirstAsync(token);
+			if (avatar is { DeletionAt: null })
+				return (_localActors.FromAvatar(avatar), default);
+			var group = await _dbEntities.Groups.MatchID(id).ExecuteFirstAsync(token);
+			if (group is { DeletionAt: null } && _localActors.FromGroup(group) is { IsFederated: true } community)
+				return (community, default);
+			return (default, await _dbEntities.ForeignAvatars.MatchID(id).ExecuteFirstAsync(token));
+		}
+
+		async Task<Relationship> Relationship(string id, CancellationToken token)
+		{
+			var (local, remote) = await Find(id, token);
+			var uri = local?.Uri ?? remote?.ActorURI;
+			var following = uri == default ? default : await _dbEntities.Followings.Match(f => f.AvatarId == MyId && f.TargetActorURI == uri).ExecuteFirstAsync(token);
+			var followedBy = uri == default ? default : await _dbEntities.Followers.Match(f => f.LocalActorId == MyId && f.ActorURI == uri).ExecuteFirstAsync(token);
+			return new Relationship
+			{
+				Id = id,
+				Following = following?.State == FollowState.Accepted,
+				Requested = following?.State == FollowState.Requested,
+				ShowingReblogs = following?.ShowReblogs ?? false,
+				FollowedBy = followedBy?.IsAccepted == true,
+				RequestedBy = followedBy is { IsAccepted: false }
+			};
+		}
+	}
+}

PrivaPub/Api/Mastodon/Controllers/AppsController.cs

@@ -0,0 +1,97 @@
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+
+using OpenIddict.Abstractions;
+
+using PrivaPub.Api.Mastodon.Auth;
+using PrivaPub.Api.Mastodon.Entities;
+using PrivaPub.Api.Mastodon.Infrastructure;
+
+using System.Security.Cryptography;
+
+using static OpenIddict.Abstractions.OpenIddictConstants;
+
+namespace PrivaPub.Api.Mastodon.Controllers
+{
+	public class AppsController : MastodonController
+	{
+		readonly IOpenIddictApplicationManager _applications;
+
+		public AppsController(IOpenIddictApplicationManager applications)
+		{
+			_applications = applications;
+		}
+
+		[HttpPost("/api/v1/apps"), AllowAnonymous]
+		public async Task<IActionResult> Create(CancellationToken token)
+		{
+			var name = Params.Get("client_name")?.Trim();
+			if (string.IsNullOrEmpty(name) || name.Length > 200)
+				return Error(StatusCodes.Status422UnprocessableEntity, "Validation failed: Application name can't be blank");
+
+			var redirects = Params.List("redirect_uris").SelectMany(r => r.Split('\n', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)).Distinct().ToList();
+			if (redirects.Count == 0 || redirects.Any(r => !Uri.TryCreate(r, UriKind.Absolute, out var uri) || uri.Scheme is "javascript" or "data"))
+				return Error(StatusCodes.Status422UnprocessableEntity, "Validation failed: Redirect URI must be an absolute URI.");
+
+			var scopes = MastodonScopes.Parse(string.Join(' ', Params.List("scopes")));
+			var descriptor = new OpenIddictApplicationDescriptor
+			{
+				ClientId = Secret(32),
+				ClientSecret = Secret(32),
+				ClientType = ClientTypes.Confidential,
+				ConsentType = ConsentTypes.Explicit,
+				DisplayName = name,
+				Permissions =
+				{
+					Permissions.Endpoints.Authorization,
+					Permissions.Endpoints.Token,
+					Permissions.Endpoints.Revocation,
+					Permissions.GrantTypes.AuthorizationCode,
+					Permissions.GrantTypes.ClientCredentials,
+					Permissions.ResponseTypes.Code
+				}
+			};
+			foreach (var scope in scopes)
+				descriptor.Permissions.Add(Permissions.Prefixes.Scope + scope);
+			foreach (var redirect in redirects)
+				descriptor.RedirectUris.Add(new Uri(redirect));
+			var website = Params.Get("website");
+			if (Uri.TryCreate(website, UriKind.Absolute, out var site) && site.Scheme is "https" or "http")
+				descriptor.Properties["website"] = System.Text.Json.JsonSerializer.SerializeToElement(website);
+
+			var application = await _applications.CreateAsync(descriptor, token);
+			return Json(new Application
+			{
+				Id = await _applications.GetIdAsync(application, token),
+				Name = name,
+				Website = website,
+				Scopes = scopes.ToList(),
+				RedirectUris = redirects,
+				RedirectUri = string.Join("\n", redirects),
+				ClientId = descriptor.ClientId,
+				ClientSecret = descriptor.ClientSecret
+			});
+		}
+
+		[HttpGet("/api/v1/apps/verify_credentials")]
+		public async Task<IActionResult> Verify(CancellationToken token)
+		{
+			var clientId = User.GetPresenters().FirstOrDefault() ?? User.GetClaim(Claims.ClientId);
+			var application = clientId == default ? default : await _applications.FindByClientIdAsync(clientId, token);
+			if (application == default)
+				return Error(StatusCodes.Status401Unauthorized, "The access token is invalid");
+			var properties = await _applications.GetPropertiesAsync(application, token);
+			return Json(new
+			{
+				id = await _applications.GetIdAsync(application, token),
+				name = await _applications.GetDisplayNameAsync(application, token),
+				website = properties.TryGetValue("website", out var website) ? website.GetString() : default,
+				scopes = User.GetScopes().ToList(),
+				redirect_uris = (await _applications.GetRedirectUrisAsync(application, token)).ToList(),
+				vapid_key = string.Empty
+			});
+		}
+
+		static string Secret(int bytes) => Convert.ToBase64String(RandomNumberGenerator.GetBytes(bytes)).TrimEnd('=').Replace('+', '-').Replace('/', '_');
+	}
+}

PrivaPub/Api/Mastodon/Controllers/InstanceController.cs

@@ -0,0 +1,107 @@
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+
+using MongoDB.Entities;
+
+using PrivaPub.Api.Mastodon.Infrastructure;
+using PrivaPub.Domain.Privacy;
+using PrivaPub.Federation.Actors;
+using PrivaPub.Models.User;
+
+using PostEntity = PrivaPub.Models.Post.Post;
+
+namespace PrivaPub.Api.Mastodon.Controllers
+{
+	public class InstanceController : MastodonController
+	{
+		public const string Version = "4.2.0 (compatible; PrivaPub)";
+		const string Description = "A small ActivityPub server where one private login keeps several unlinkable public personas.";
+
+		readonly ILocalActorService _localActors;
+
+		public InstanceController(ILocalActorService localActors)
+		{
+			_localActors = localActors;
+		}
+
+		string Domain => new Uri(_localActors.BaseAddress).Authority;
+
+		static object Statuses => new { max_characters = 5000, max_media_attachments = 4, characters_reserved_per_url = 23 };
+
+		static object MediaAttachments => new
+		{
+			supported_mime_types = new[] { "image/jpeg", "image/png", "image/gif", "image/webp", "video/mp4", "video/webm", "audio/mpeg", "audio/ogg" },
+			image_size_limit = 16 * 1024 * 1024,
+			image_matrix_limit = 16_777_216,
+			video_size_limit = 99 * 1024 * 1024,
+			video_frame_rate_limit = 60,
+			video_matrix_limit = 2_304_000
+		};
+
+		static object Polls => new { max_options = 4, max_characters_per_option = 50, min_expiration = 300, max_expiration = 2_629_746 };
+
+		[HttpGet("/api/v1/instance"), AllowAnonymous]
+		public async Task<IActionResult> V1(CancellationToken token)
+		{
+			var users = await DB.Default.CountAsync<Avatar>(a => !a.DeletionAt.HasValue, token);
+			var statuses = await DB.Default.CountAsync<PostEntity>(f => f.Where(p => !p.IsFederatedCopy) & f.Where(VisibilityPolicy.IsPublic), token);
+			var domains = (await DB.Default.Find<ForeignAvatar, string>().Project(a => a.Domain).ExecuteAsync(token)).Distinct().Count();
+			return Json(new
+			{
+				uri = Domain,
+				title = "PrivaPub",
+				short_description = Description,
+				description = Description,
+				email = string.Empty,
+				version = Version,
+				urls = new { streaming_api = $"wss://{Domain}" },
+				stats = new { user_count = users, status_count = statuses, domain_count = domains },
+				thumbnail = $"{_localActors.BaseAddress}/media/missing-header.png",
+				languages = new[] { "en" },
+				registrations = false,
+				approval_required = false,
+				invites_enabled = false,
+				configuration = new { accounts = new { max_featured_tags = 0 }, statuses = Statuses, media_attachments = MediaAttachments, polls = Polls },
+				contact_account = default(object),
+				rules = Array.Empty<object>()
+			});
+		}
+
+		[HttpGet("/api/v2/instance"), AllowAnonymous]
+		public IActionResult V2() => Json(new
+		{
+			domain = Domain,
+			title = "PrivaPub",
+			version = Version,
+			source_url = "https://git.thepra.dev/thepra/SocialPub",
+			description = Description,
+			usage = new { users = new { active_month = 0 } },
+			thumbnail = new { url = $"{_localActors.BaseAddress}/media/missing-header.png" },
+			languages = new[] { "en" },
+			configuration = new
+			{
+				urls = new { streaming = $"wss://{Domain}" },
+				accounts = new { max_featured_tags = 0, max_pinned_statuses = 0 },
+				statuses = Statuses,
+				media_attachments = MediaAttachments,
+				polls = Polls,
+				translation = new { enabled = false }
+			},
+			registrations = new { enabled = false, approval_required = false, message = default(string) },
+			contact = new { email = string.Empty, account = default(object) },
+			rules = Array.Empty<object>()
+		});
+
+		[HttpGet("/api/v1/instance/peers"), AllowAnonymous]
+		public IActionResult Peers() => Json(Array.Empty<string>());
+
+		[HttpGet("/api/v1/instance/activity"), AllowAnonymous]
+		public IActionResult Activity() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/instance/rules"), AllowAnonymous]
+		public IActionResult Rules() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/instance/extended_description"), AllowAnonymous]
+		public IActionResult ExtendedDescription() => Json(new { updated_at = MastodonJson.Day(DateTime.UtcNow), content = $"<p>{Description}</p>" });
+	}
+}

PrivaPub/Api/Mastodon/Controllers/SearchController.cs

@@ -0,0 +1,149 @@
+using Microsoft.AspNetCore.Mvc;
+
+using PrivaPub.Api.Mastodon.Entities;
+using PrivaPub.Api.Mastodon.Infrastructure;
+using PrivaPub.Api.Mastodon.Mappers;
+using PrivaPub.Domain.Privacy;
+using PrivaPub.Federation.Actors;
+using PrivaPub.Federation.Inbox;
+using PrivaPub.Federation.Outbox;
+using PrivaPub.Domain.Social;
+using PrivaPub.Models.Post;
+using PrivaPub.StaticServices;
+
+using PostEntity = PrivaPub.Models.Post.Post;
+
+namespace PrivaPub.Api.Mastodon.Controllers
+{
+	public class SearchController : MastodonController
+	{
+		readonly MastodonMapper _mapper;
+		readonly DbEntities _dbEntities;
+		readonly ILocalActorService _localActors;
+		readonly IRemoteActorService _remoteActors;
+		readonly IRemotePosts _remotePosts;
+		readonly AccountSearch _search;
+
+		public SearchController(MastodonMapper mapper, DbEntities dbEntities, ILocalActorService localActors, IRemoteActorService remoteActors,
+			IRemotePosts remotePosts, AccountSearch search)
+		{
+			_mapper = mapper;
+			_dbEntities = dbEntities;
+			_localActors = localActors;
+			_remoteActors = remoteActors;
+			_remotePosts = remotePosts;
+			_search = search;
+		}
+
+		[HttpGet("/api/v2/search"), Scope("read:search", requiresUser: false)]
+		public async Task<IActionResult> Search(CancellationToken token)
+		{
+			var q = Params.Get("q")?.Trim();
+			var type = Params.Get("type");
+			var resolve = Params.Bool("resolve") == true && MyId != default;
+			var results = new SearchResults();
+			if (string.IsNullOrEmpty(q))
+				return Json(results);
+
+			if (q.StartsWith("https://", StringComparison.OrdinalIgnoreCase))
+			{
+				var post = await _dbEntities.Posts.Match(p => (p.ObjectURI == q || p.Url == q) && !p.DeletedAt.HasValue).ExecuteFirstAsync(token);
+				if (post == default && resolve && type is null or "statuses")
+					post = await _remotePosts.StoreContext(q, 0, token);
+				if (post != default && type is null or "statuses" && await VisibilityPolicy.CanSee(post, MyId, token))
+					results.Statuses.Add(await _mapper.Status(post, MyId, token));
+				if (results.Statuses.Count == 0 && type is null or "accounts")
+				{
+					var local = await _localActors.FindByUri(q, token);
+					var foreign = local == default ? (resolve ? await _remoteActors.GetActor(q, refresh: false, token) : default) : default;
+					if (local is { IsFederated: true })
+						results.Accounts.Add(await _mapper.Local(local, false, token));
+					else if (foreign != default)
+						results.Accounts.Add(_mapper.Foreign(foreign));
+				}
+				return Json(results);
+			}
+
+			if (type is null or "accounts")
+			{
+				results.Accounts = await _search.Find(q, resolve, Limit(), token);
+			}
+			if (type is null or "hashtags" && q.TrimStart('#') is { Length: > 0 } tag)
+				results.Hashtags.Add(new { name = tag.ToLowerInvariant(), url = $"{_localActors.BaseAddress}/tags/{Uri.EscapeDataString(tag.ToLowerInvariant())}", history = Array.Empty<object>() });
+			return Json(results);
+		}
+	}
+
+	public class StubsController : MastodonController
+	{
+		[HttpGet("/api/v1/custom_emojis"), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public IActionResult CustomEmojis() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/filters"), Scope("read:filters")]
+		public IActionResult FiltersV1() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v2/filters"), Scope("read:filters")]
+		public IActionResult FiltersV2() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/lists"), Scope("read:lists")]
+		public IActionResult Lists() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/announcements"), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public IActionResult Announcements() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/trends"), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public IActionResult Trends() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/trends/tags"), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public IActionResult TrendTags() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/trends/statuses"), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public IActionResult TrendStatuses() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/trends/links"), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public IActionResult TrendLinks() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/suggestions"), Scope("read")]
+		public IActionResult SuggestionsV1() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v2/suggestions"), Scope("read")]
+		public IActionResult SuggestionsV2() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/followed_tags"), Scope("read:follows")]
+		public IActionResult FollowedTags() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/blocks"), Scope("read:blocks")]
+		public IActionResult Blocks() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/mutes"), Scope("read:mutes")]
+		public IActionResult Mutes() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/domain_blocks"), Scope("read:blocks")]
+		public IActionResult DomainBlocks() => Json(Array.Empty<string>());
+
+		[HttpGet("/api/v1/bookmarks"), Scope("read:bookmarks")]
+		public IActionResult Bookmarks() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/endorsements"), Scope("read:accounts")]
+		public IActionResult Endorsements() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/featured_tags"), Scope("read:accounts")]
+		public IActionResult FeaturedTags() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/scheduled_statuses"), Scope("read:statuses")]
+		public IActionResult ScheduledStatuses() => Json(Array.Empty<object>());
+
+		[HttpGet("/api/v1/preferences"), Scope("read:accounts")]
+		public IActionResult Preferences() => Json(new Dictionary<string, object>
+		{
+			["posting:default:visibility"] = Me.Settings.DefaultVisibility ?? "public",
+			["posting:default:sensitive"] = Me.Settings.DefaultSensitive,
+			["posting:default:language"] = Me.Settings.DefaultLanguage,
+			["reading:expand:media"] = "default",
+			["reading:expand:spoilers"] = false
+		});
+
+		[HttpGet("/api/v1/push/subscription"), Scope("push")]
+		public IActionResult PushSubscription() => Error(StatusCodes.Status404NotFound, "Record not found");
+	}
+}

PrivaPub/Api/Mastodon/Controllers/StatusesController.cs

@@ -0,0 +1,276 @@
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Extensions.Caching.Memory;
+
+using MongoDB.Entities;
+
+using PrivaPub.Api.Mastodon.Entities;
+using PrivaPub.Api.Mastodon.Infrastructure;
+using PrivaPub.Api.Mastodon.Mappers;
+using PrivaPub.Domain.Privacy;
+using PrivaPub.Domain.Statuses;
+using PrivaPub.Models.Post;
+using PrivaPub.StaticServices;
+
+using PostEntity = PrivaPub.Models.Post.Post;
+
+namespace PrivaPub.Api.Mastodon.Controllers
+{
+	public class StatusesController : MastodonController
+	{
+		const int MaxContext = 200;
+
+		readonly IStatusService _statuses;
+		readonly MastodonMapper _mapper;
+		readonly DbEntities _dbEntities;
+		readonly IMemoryCache _cache;
+
+		public StatusesController(IStatusService statuses, MastodonMapper mapper, DbEntities dbEntities, IMemoryCache cache)
+		{
+			_statuses = statuses;
+			_mapper = mapper;
+			_dbEntities = dbEntities;
+			_cache = cache;
+		}
+
+		[HttpPost("/api/v1/statuses"), Scope("write:statuses")]
+		public async Task<IActionResult> Create(CancellationToken token)
+		{
+			var idempotency = Request.Headers["Idempotency-Key"].ToString();
+			var cacheKey = string.IsNullOrEmpty(idempotency) ? default : $"idempotency:{MyId}:{idempotency}";
+			if (cacheKey != default && _cache.TryGetValue(cacheKey, out string earlier))
+			{
+				var existing = await _dbEntities.Posts.MatchID(earlier).ExecuteFirstAsync(token);
+				if (existing != default)
+					return Json(await _mapper.Status(existing, MyId, token));
+			}
+			if (Params.List("media_ids").Count > 0)
+				return Error(StatusCodes.Status422UnprocessableEntity, "Validation failed: Media attachments are not supported yet");
+			if (Params.Has("poll[options]"))
+				return Error(StatusCodes.Status422UnprocessableEntity, "Validation failed: Polls are not supported yet");
+
+			var outcome = await _statuses.Publish(Me, new StatusDraft
+			{
+				Text = Params.Get("status"),
+				PlainText = true,
+				SpoilerText = Params.Get("spoiler_text"),
+				Sensitive = Params.Bool("sensitive") ?? Me.Settings.DefaultSensitive,
+				Visibility = Visibility(Params.Get("visibility") ?? Me.Settings.DefaultVisibility),
+				InReplyTo = Params.Get("in_reply_to_id"),
+				Language = Params.Get("language") ?? Me.Settings.DefaultLanguage
+			}, token);
+			if (!outcome.Ok)
+				return Error(outcome.Status, outcome.Error);
+			if (cacheKey != default)
+				_cache.Set(cacheKey, outcome.Post.ID, TimeSpan.FromHours(1));
+			return Json(await _mapper.Status(outcome.Post, MyId, token));
+		}
+
+		[HttpGet("/api/v1/statuses"), Scope("read:statuses", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public async Task<IActionResult> Many(CancellationToken token)
+		{
+			var ids = Params.List("id").Take(20).ToList();
+			var posts = await _dbEntities.Posts.Match(p => ids.Contains(p.ID) && !p.DeletedAt.HasValue).ExecuteAsync(token);
+			var visible = new List<PostEntity>();
+			foreach (var post in posts)
+				if (await VisibilityPolicy.CanSee(post, MyId, token))
+					visible.Add(post);
+			return Json(await _mapper.Statuses(visible, MyId, token));
+		}
+
+		[HttpGet("/api/v1/statuses/{id}"), Scope("read:statuses", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public async Task<IActionResult> Get(string id, CancellationToken token)
+		{
+			var post = await Visible(id, token);
+			return post == default ? NotFoundError() : Json(await _mapper.Status(post, MyId, token));
+		}
+
+		[HttpPut("/api/v1/statuses/{id}"), Scope("write:statuses")]
+		public async Task<IActionResult> Edit(string id, CancellationToken token)
+		{
+			if (Params.List("media_ids").Count > 0)
+				return Error(StatusCodes.Status422UnprocessableEntity, "Validation failed: Media attachments are not supported yet");
+			var outcome = await _statuses.Edit(Me, id, new StatusDraft
+			{
+				Text = Params.Get("status"),
+				PlainText = true,
+				SpoilerText = Params.Get("spoiler_text"),
+				Sensitive = Params.Bool("sensitive") ?? false,
+				Language = Params.Get("language")
+			}, token);
+			return outcome.Ok ? Json(await _mapper.Status(outcome.Post, MyId, token)) : Error(outcome.Status, outcome.Error);
+		}
+
+		[HttpDelete("/api/v1/statuses/{id}"), Scope("write:statuses")]
+		public async Task<IActionResult> Delete(string id, CancellationToken token)
+		{
+			var before = await _dbEntities.Posts.Match(p => p.ID == id && p.GroupUserId == MyId && !p.IsFederatedCopy && !p.DeletedAt.HasValue).ExecuteFirstAsync(token);
+			if (before == default)
+				return NotFoundError();
+			var status = await _mapper.Status(before, MyId, token);
+			var outcome = await _statuses.Remove(Me, id, token);
+			if (!outcome.Ok)
+				return Error(outcome.Status, outcome.Error);
+			if (status != default)
+			{
+				status.Text = before.Text;
+				status.SpoilerText = before.SpoilerText ?? string.Empty;
+			}
+			return Json(status);
+		}
+
+		[HttpGet("/api/v1/statuses/{id}/context"), Scope("read:statuses", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public async Task<IActionResult> Context(string id, CancellationToken token)
+		{
+			var post = await Visible(id, token);
+			if (post == default)
+				return NotFoundError();
+
+			var ancestors = new List<PostEntity>();
+			var cursor = post;
+			while (!string.IsNullOrEmpty(cursor.AnsweringToPostId) && ancestors.Count < MaxContext)
+			{
+				cursor = await _dbEntities.Posts.MatchID(cursor.AnsweringToPostId).ExecuteFirstAsync(token);
+				if (cursor == default || cursor.DeletedAt.HasValue || !await VisibilityPolicy.CanSee(cursor, MyId, token))
+					break;
+				ancestors.Insert(0, cursor);
+			}
+
+			var descendants = new List<PostEntity>();
+			var frontier = new List<string> { post.ID };
+			while (frontier.Count > 0 && descendants.Count < MaxContext)
+			{
+				var parents = frontier;
+				var children = await _dbEntities.Posts.Match(p => parents.Contains(p.AnsweringToPostId) && !p.DeletedAt.HasValue && p.ReblogOfPostId == null)
+					.Sort(p => p.ID, Order.Ascending).Limit(MaxContext).ExecuteAsync(token);
+				frontier = new List<string>();
+				foreach (var child in children)
+					if (await VisibilityPolicy.CanSee(child, MyId, token))
+					{
+						descendants.Add(child);
+						frontier.Add(child.ID);
+					}
+			}
+			return Json(new Context
+			{
+				Ancestors = await _mapper.Statuses(ancestors, MyId, token),
+				Descendants = await _mapper.Statuses(descendants.OrderBy(d => d.ID, StringComparer.Ordinal).ToList(), MyId, token)
+			});
+		}
+
+		[HttpGet("/api/v1/statuses/{id}/history"), Scope("read:statuses", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public async Task<IActionResult> History(string id, CancellationToken token)
+		{
+			var post = await Visible(id, token);
+			if (post == default)
+				return NotFoundError();
+			var account = await _mapper.Account(MastodonMapper.AuthorOf(post), token);
+			var edits = post.Revisions.Select(r => new StatusEdit
+			{
+				Content = r.ContentHtml ?? string.Empty,
+				SpoilerText = r.SpoilerText ?? string.Empty,
+				Sensitive = r.HasContentWarning,
+				CreatedAt = MastodonJson.Time(r.EditedAt),
+				Account = account
+			}).ToList();
+			edits.Add(new StatusEdit
+			{
+				Content = MastodonMapper.Content(post),
+				SpoilerText = post.SpoilerText ?? string.Empty,
+				Sensitive = post.HasContentWarning,
+				CreatedAt = MastodonJson.Time(post.EditedAt ?? post.CreationDate),
+				Account = account
+			});
+			return Json(edits);
+		}
+
+		[HttpGet("/api/v1/statuses/{id}/source"), Scope("read:statuses")]
+		public async Task<IActionResult> Source(string id, CancellationToken token)
+		{
+			var post = await _dbEntities.Posts.Match(p => p.ID == id && p.GroupUserId == MyId && !p.IsFederatedCopy && !p.DeletedAt.HasValue).ExecuteFirstAsync(token);
+			return post == default ? NotFoundError() : Json(new StatusSource { Id = post.ID, Text = post.Text ?? string.Empty, SpoilerText = post.SpoilerText ?? string.Empty });
+		}
+
+		[HttpPost("/api/v1/statuses/{id}/favourite"), Scope("write:favourites")]
+		public Task<IActionResult> Favourite(string id, CancellationToken token) => Toggle(_statuses.Favourite(Me, id, true, token), id, token);
+
+		[HttpPost("/api/v1/statuses/{id}/unfavourite"), Scope("write:favourites")]
+		public Task<IActionResult> Unfavourite(string id, CancellationToken token) => Toggle(_statuses.Favourite(Me, id, false, token), id, token);
+
+		[HttpPost("/api/v1/statuses/{id}/reblog"), Scope("write:statuses")]
+		public async Task<IActionResult> Reblog(string id, CancellationToken token)
+		{
+			var outcome = await _statuses.Reblog(Me, id, true, Visibility(Params.Get("visibility")), token);
+			return outcome.Ok ? Json(await _mapper.Status(outcome.Post, MyId, token)) : Error(outcome.Status, outcome.Error);
+		}
+
+		[HttpPost("/api/v1/statuses/{id}/unreblog"), Scope("write:statuses")]
+		public Task<IActionResult> Unreblog(string id, CancellationToken token) => Toggle(_statuses.Reblog(Me, id, false, PostVisibility.Public, token), id, token);
+
+		[HttpGet("/api/v1/statuses/{id}/favourited_by"), Scope("read:accounts", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public async Task<IActionResult> FavouritedBy(string id, CancellationToken token)
+		{
+			if (await Visible(id, token) == default)
+				return NotFoundError();
+			var favourites = await _dbEntities.Favourites.Match(f => f.PostId == id).Sort(f => f.ID, Order.Descending).Limit(Limit(40, 80)).ExecuteAsync(token);
+			var accounts = await _mapper.Accounts(favourites.Select(f => f.AccountId), token);
+			return Json(favourites.Select(f => accounts.GetValueOrDefault(f.AccountId)).Where(a => a != default).ToList());
+		}
+
+		[HttpGet("/api/v1/statuses/{id}/reblogged_by"), Scope("read:accounts", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public async Task<IActionResult> RebloggedBy(string id, CancellationToken token)
+		{
+			if (await Visible(id, token) == default)
+				return NotFoundError();
+			var reblogs = await _dbEntities.Posts.Match(p => p.ReblogOfPostId == id && !p.DeletedAt.HasValue).Sort(p => p.ID, Order.Descending).Limit(Limit(40, 80)).ExecuteAsync(token);
+			var accounts = await _mapper.Accounts(reblogs.Select(MastodonMapper.AuthorOf), token);
+			return Json(reblogs.Select(r => accounts.GetValueOrDefault(MastodonMapper.AuthorOf(r))).Where(a => a != default).ToList());
+		}
+
+		[HttpPost("/api/v1/statuses/{id}/bookmark"), Scope("write:bookmarks")]
+		public Task<IActionResult> Bookmark(string id, CancellationToken token) => Unchanged(id, token);
+
+		[HttpPost("/api/v1/statuses/{id}/unbookmark"), Scope("write:bookmarks")]
+		public Task<IActionResult> Unbookmark(string id, CancellationToken token) => Unchanged(id, token);
+
+		[HttpPost("/api/v1/statuses/{id}/mute"), Scope("write:mutes")]
+		public Task<IActionResult> Mute(string id, CancellationToken token) => Unchanged(id, token);
+
+		[HttpPost("/api/v1/statuses/{id}/unmute"), Scope("write:mutes")]
+		public Task<IActionResult> Unmute(string id, CancellationToken token) => Unchanged(id, token);
+
+		[HttpPost("/api/v1/statuses/{id}/pin"), Scope("write:accounts")]
+		public IActionResult Pin(string id) => Error(StatusCodes.Status422UnprocessableEntity, "Validation failed: Pinning is not supported yet");
+
+		[HttpPost("/api/v1/statuses/{id}/unpin"), Scope("write:accounts")]
+		public Task<IActionResult> Unpin(string id, CancellationToken token) => Unchanged(id, token);
+
+		async Task<IActionResult> Toggle(Task<StatusOutcome> action, string id, CancellationToken token)
+		{
+			var outcome = await action;
+			if (!outcome.Ok)
+				return Error(outcome.Status, outcome.Error);
+			var post = await _dbEntities.Posts.MatchID(id).ExecuteFirstAsync(token);
+			return Json(await _mapper.Status(post, MyId, token));
+		}
+
+		async Task<IActionResult> Unchanged(string id, CancellationToken token)
+		{
+			var post = await Visible(id, token);
+			return post == default ? NotFoundError() : Json(await _mapper.Status(post, MyId, token));
+		}
+
+		async Task<PostEntity> Visible(string id, CancellationToken token)
+		{
+			var post = await _dbEntities.Posts.Match(p => p.ID == id && !p.DeletedAt.HasValue).ExecuteFirstAsync(token);
+			return post != default && post.Visibility != PostVisibility.LocalGeo && await VisibilityPolicy.CanSee(post, MyId, token) ? post : default;
+		}
+
+		static PostVisibility Visibility(string value) => value?.ToLowerInvariant() switch
+		{
+			"unlisted" => PostVisibility.Unlisted,
+			"private" => PostVisibility.FollowersOnly,
+			"direct" => PostVisibility.Direct,
+			_ => PostVisibility.Public
+		};
+	}
+}

PrivaPub/Api/Mastodon/Controllers/TimelinesController.cs

@@ -0,0 +1,243 @@
+using Microsoft.AspNetCore.Mvc;
+
+using MongoDB.Entities;
+
+using PrivaPub.Api.Mastodon.Entities;
+using PrivaPub.Api.Mastodon.Infrastructure;
+using PrivaPub.Api.Mastodon.Mappers;
+using PrivaPub.Domain.Privacy;
+using PrivaPub.Models.Post;
+using PrivaPub.Models.Social;
+using PrivaPub.StaticServices;
+
+using PostEntity = PrivaPub.Models.Post.Post;
+using NotificationEntity = PrivaPub.Models.Social.Notification;
+using MarkerEntity = PrivaPub.Models.Social.Marker;
+
+namespace PrivaPub.Api.Mastodon.Controllers
+{
+	public class TimelinesController : MastodonController
+	{
+		readonly MastodonMapper _mapper;
+		readonly DbEntities _dbEntities;
+
+		public TimelinesController(MastodonMapper mapper, DbEntities dbEntities)
+		{
+			_mapper = mapper;
+			_dbEntities = dbEntities;
+		}
+
+		[HttpGet("/api/v1/timelines/home"), Scope("read:statuses")]
+		public async Task<IActionResult> Home(CancellationToken token)
+		{
+			var entries = await Page.From(Params, Limit()).Fetch(_dbEntities.TimelineEntries.Match(e => e.AvatarId == MyId), e => e.PostId, token);
+			var ids = entries.Select(e => e.PostId).ToList();
+			var posts = (await _dbEntities.Posts.Match(p => ids.Contains(p.ID) && !p.DeletedAt.HasValue).ExecuteAsync(token)).ToDictionary(p => p.ID);
+			var statuses = await _mapper.Statuses(ids.Where(posts.ContainsKey).Select(id => posts[id]).ToList(), MyId, token);
+			Link("/api/v1/timelines/home", entries.LastOrDefault()?.PostId, entries.FirstOrDefault()?.PostId);
+			return Json(statuses);
+		}
+
+		[HttpGet("/api/v1/timelines/public"), Scope("read:statuses", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public async Task<IActionResult> Public(CancellationToken token)
+		{
+			var query = _dbEntities.Posts.Match(p => p.Visibility == PostVisibility.Public && !p.DeletedAt.HasValue && p.ReblogOfPostId == null);
+			if (Params.Bool("local") == true)
+				query.Match(p => !p.IsFederatedCopy);
+			if (Params.Bool("remote") == true)
+				query.Match(p => p.IsFederatedCopy);
+			if (Params.Bool("only_media") == true)
+				query.Match(p => p.Media.Count > 0);
+			return await Respond(query, "/api/v1/timelines/public", token);
+		}
+
+		[HttpGet("/api/v1/timelines/tag/{hashtag}"), Scope("read:statuses", requiresUser: false), Microsoft.AspNetCore.Authorization.AllowAnonymous]
+		public async Task<IActionResult> Tag(string hashtag, CancellationToken token)
+		{
+			var tag = hashtag.TrimStart('#').ToLowerInvariant();
+			var query = _dbEntities.Posts.Match(p => p.Tags.Contains(tag) && p.Visibility == PostVisibility.Public && !p.DeletedAt.HasValue && p.ReblogOfPostId == null);
+			if (Params.Bool("local") == true)
+				query.Match(p => !p.IsFederatedCopy);
+			return await Respond(query, $"/api/v1/timelines/tag/{hashtag}", token);
+		}
+
+		[HttpGet("/api/v1/timelines/list/{id}"), Scope("read:lists")]
+		public IActionResult List(string id) => Json(Array.Empty<Status>());
+
+		[HttpGet("/api/v1/favourites"), Scope("read:favourites")]
+		public async Task<IActionResult> Favourites(CancellationToken token)
+		{
+			var favourites = await Page.From(Params, Limit()).Fetch(_dbEntities.Favourites.Match(f => f.AccountId == MyId), f => f.ID, token);
+			var ids = favourites.Select(f => f.PostId).ToList();
+			var posts = (await _dbEntities.Posts.Match(p => ids.Contains(p.ID) && !p.DeletedAt.HasValue).ExecuteAsync(token)).ToDictionary(p => p.ID);
+			var visible = new List<PostEntity>();
+			foreach (var id in ids.Where(posts.ContainsKey))
+				if (await VisibilityPolicy.CanSee(posts[id], MyId, token))
+					visible.Add(posts[id]);
+			Link("/api/v1/favourites", favourites.LastOrDefault()?.ID, favourites.FirstOrDefault()?.ID);
+			return Json(await _mapper.Statuses(visible, MyId, token));
+		}
+
+		[HttpGet("/api/v1/conversations"), Scope("read:statuses")]
+		public async Task<IActionResult> Conversations(CancellationToken token)
+		{
+			var groups = await _dbEntities.DmGroups.Match(g => !g.DeletionAt.HasValue && g.Members.Any(m => !m.IsForeign && m.AvatarId == MyId))
+				.Sort(g => g.UpdatedAt, Order.Descending).Limit(Limit()).ExecuteAsync(token);
+			var conversations = new List<Conversation>();
+			foreach (var group in groups)
+			{
+				var last = await _dbEntities.Posts.Match(p => p.ConversationId == group.ID && !p.DeletedAt.HasValue).Sort(p => p.ID, Order.Descending).ExecuteFirstAsync(token);
+				if (last == default)
+					continue;
+				var others = new List<string>();
+				foreach (var member in group.Members.Where(m => !(m.AvatarId == MyId && !m.IsForeign)))
+					others.Add(member.IsForeign
+						? (await _dbEntities.ForeignAvatars.Match(f => f.ActorURI == member.AvatarId).ExecuteFirstAsync(token))?.ID
+						: member.AvatarId);
+				var accounts = await _mapper.Accounts(others, token);
+				conversations.Add(new Conversation
+				{
+					Id = group.ID,
+					Accounts = accounts.Values.ToList(),
+					LastStatus = await _mapper.Status(last, MyId, token)
+				});
+			}
+			return Json(conversations);
+		}
+
+		[HttpPost("/api/v1/conversations/{id}/read"), Scope("write:conversations")]
+		public async Task<IActionResult> ReadConversation(string id, CancellationToken token)
+		{
+			var group = await _dbEntities.DmGroups.Match(g => g.ID == id && g.Members.Any(m => !m.IsForeign && m.AvatarId == MyId)).ExecuteFirstAsync(token);
+			if (group == default)
+				return NotFoundError();
+			var last = await _dbEntities.Posts.Match(p => p.ConversationId == group.ID && !p.DeletedAt.HasValue).Sort(p => p.ID, Order.Descending).ExecuteFirstAsync(token);
+			return Json(new Conversation { Id = group.ID, LastStatus = last == default ? default : await _mapper.Status(last, MyId, token) });
+		}
+
+		[HttpGet("/api/v1/markers"), Scope("read:statuses")]
+		public async Task<IActionResult> Markers(CancellationToken token)
+		{
+			var wanted = Params.List("timeline");
+			var markers = await DB.Default.Find<MarkerEntity>().Match(m => m.AvatarId == MyId).ExecuteAsync(token);
+			return Json(markers.Where(m => wanted.Count == 0 || wanted.Contains(m.Timeline))
+				.ToDictionary(m => m.Timeline, m => new Entities.Marker { LastReadId = m.LastReadId, Version = m.Version, UpdatedAt = MastodonJson.Time(m.UpdatedAt) }));
+		}
+
+		[HttpPost("/api/v1/markers"), Scope("write:statuses")]
+		public async Task<IActionResult> SaveMarkers(CancellationToken token)
+		{
+			var result = new Dictionary<string, Entities.Marker>();
+			foreach (var timeline in new[] { "home", "notifications" })
+			{
+				var lastRead = Params.Get($"{timeline}[last_read_id]");
+				if (string.IsNullOrEmpty(lastRead))
+					continue;
+				var marker = await DB.Default.UpdateAndGet<MarkerEntity>()
+					.Match(m => m.AvatarId == MyId && m.Timeline == timeline)
+					.Modify(m => m.LastReadId, lastRead)
+					.Modify(m => m.UpdatedAt, DateTime.UtcNow)
+					.Modify(b => b.Inc(m => m.Version, 1))
+					.Option(o => o.IsUpsert = true)
+					.ExecuteAsync(token);
+				result[timeline] = new Entities.Marker { LastReadId = marker.LastReadId, Version = marker.Version, UpdatedAt = MastodonJson.Time(marker.UpdatedAt) };
+			}
+			return Json(result);
+		}
+
+		async Task<IActionResult> Respond(Find<PostEntity, PostEntity> query, string path, CancellationToken token)
+		{
+			var posts = await Page.From(Params, Limit()).Fetch(query, p => p.ID, token);
+			Link(path, posts.LastOrDefault()?.ID, posts.FirstOrDefault()?.ID);
+			return Json(await _mapper.Statuses(posts, MyId, token));
+		}
+	}
+
+	public class NotificationsController : MastodonController
+	{
+		static readonly Dictionary<NotificationType, string> Names = new()
+		{
+			[NotificationType.Mention] = "mention",
+			[NotificationType.Follow] = "follow",
+			[NotificationType.FollowRequest] = "follow_request",
+			[NotificationType.Favourite] = "favourite",
+			[NotificationType.Reblog] = "reblog",
+			[NotificationType.Update] = "update"
+		};
+
+		readonly MastodonMapper _mapper;
+		readonly DbEntities _dbEntities;
+
+		public NotificationsController(MastodonMapper mapper, DbEntities dbEntities)
+		{
+			_mapper = mapper;
+			_dbEntities = dbEntities;
+		}
+
+		[HttpGet("/api/v1/notifications"), Scope("read:notifications")]
+		public async Task<IActionResult> List(CancellationToken token)
+		{
+			var types = Params.List("types").Select(Parse).Where(t => t.HasValue).Select(t => t.Value).ToList();
+			var excluded = Params.List("exclude_types").Select(Parse).Where(t => t.HasValue).Select(t => t.Value).ToList();
+			var query = _dbEntities.Notifications.Match(n => n.AvatarId == MyId);
+			if (types.Count > 0)
+				query.Match(n => types.Contains(n.Type));
+			if (excluded.Count > 0)
+				query.Match(n => !excluded.Contains(n.Type));
+			if (Params.Get("account_id") is { } accountId)
+				query.Match(n => n.FromAccountId == accountId);
+			var notifications = await Page.From(Params, Limit(15, 30)).Fetch(query, n => n.ID, token);
+			Link("/api/v1/notifications", notifications.LastOrDefault()?.ID, notifications.FirstOrDefault()?.ID);
+			return Json(await Map(notifications, token));
+		}
+
+		[HttpGet("/api/v1/notifications/{id}"), Scope("read:notifications")]
+		public async Task<IActionResult> Get(string id, CancellationToken token)
+		{
+			var notification = await _dbEntities.Notifications.Match(n => n.ID == id && n.AvatarId == MyId).ExecuteFirstAsync(token);
+			return notification == default ? NotFoundError() : Json((await Map(new List<NotificationEntity> { notification }, token)).FirstOrDefault());
+		}
+
+		[HttpPost("/api/v1/notifications/clear"), Scope("write:notifications")]
+		public async Task<IActionResult> Clear(CancellationToken token)
+		{
+			await DB.Default.DeleteAsync<NotificationEntity>(n => n.AvatarId == MyId);
+			return Json(new { });
+		}
+
+		[HttpPost("/api/v1/notifications/{id}/dismiss"), Scope("write:notifications")]
+		public async Task<IActionResult> Dismiss(string id, CancellationToken token)
+		{
+			await DB.Default.DeleteAsync<NotificationEntity>(n => n.ID == id && n.AvatarId == MyId);
+			return Json(new { });
+		}
+
+		[HttpGet("/api/v1/notifications/unread_count"), Scope("read:notifications")]
+		public async Task<IActionResult> UnreadCount(CancellationToken token) =>
+			Json(new { count = await DB.Default.CountAsync<NotificationEntity>(n => n.AvatarId == MyId && !n.IsRead, token) });
+
+		async Task<List<Entities.Notification>> Map(List<NotificationEntity> notifications, CancellationToken token)
+		{
+			var accounts = await _mapper.Accounts(notifications.Select(n => n.FromAccountId), token);
+			var postIds = notifications.Where(n => n.PostId != default).Select(n => n.PostId).Distinct().ToList();
+			var posts = postIds.Count == 0
+				? new List<PostEntity>()
+				: await _dbEntities.Posts.Match(p => postIds.Contains(p.ID) && !p.DeletedAt.HasValue).ExecuteAsync(token);
+			var statuses = (await _mapper.Statuses(posts, MyId, token)).ToDictionary(s => s.Id);
+			return notifications
+				.Where(n => accounts.ContainsKey(n.FromAccountId ?? string.Empty) && (n.PostId == default || statuses.ContainsKey(n.PostId)))
+				.Select(n => new Entities.Notification
+				{
+					Id = n.ID,
+					Type = Names[n.Type],
+					CreatedAt = MastodonJson.Time(n.CreatedAt),
+					GroupKey = $"ungrouped-{n.ID}",
+					Account = accounts[n.FromAccountId],
+					Status = n.PostId == default ? default : statuses[n.PostId]
+				})
+				.ToList();
+		}
+
+		static NotificationType? Parse(string name) => Names.FirstOrDefault(n => n.Value == name) is { Value: not null } pair ? pair.Key : (NotificationType?)null;
+	}
+}

PrivaPub/Api/Mastodon/Entities/Entities.cs

@@ -0,0 +1,200 @@
+namespace PrivaPub.Api.Mastodon.Entities
+{
+	public class Account
+	{
+		public string Id { get; set; }
+		public string Username { get; set; }
+		public string Acct { get; set; }
+		public string DisplayName { get; set; }
+		public bool Locked { get; set; }
+		public bool Bot { get; set; }
+		public bool? Discoverable { get; set; }
+		public bool Indexable { get; set; }
+		public bool Group { get; set; }
+		public string CreatedAt { get; set; }
+		public string Note { get; set; }
+		public string Url { get; set; }
+		public string Uri { get; set; }
+		public string Avatar { get; set; }
+		public string AvatarStatic { get; set; }
+		public string Header { get; set; }
+		public string HeaderStatic { get; set; }
+		public int FollowersCount { get; set; }
+		public int FollowingCount { get; set; }
+		public int StatusesCount { get; set; }
+		public string LastStatusAt { get; set; }
+		public bool? HideCollections { get; set; }
+		public bool Noindex { get; set; } = true;
+		public List<object> Emojis { get; set; } = new();
+		public List<object> Roles { get; set; } = new();
+		public List<Field> Fields { get; set; } = new();
+		public Source Source { get; set; }
+	}
+
+	public class Field
+	{
+		public string Name { get; set; }
+		public string Value { get; set; }
+		public string VerifiedAt { get; set; }
+	}
+
+	public class Source
+	{
+		public string Privacy { get; set; } = "public";
+		public bool Sensitive { get; set; }
+		public string Language { get; set; }
+		public string Note { get; set; } = string.Empty;
+		public List<Field> Fields { get; set; } = new();
+		public int FollowRequestsCount { get; set; }
+		public string AttributionDomains { get; set; }
+	}
+
+	public class Status
+	{
+		public string Id { get; set; }
+		public string Uri { get; set; }
+		public string Url { get; set; }
+		public Account Account { get; set; }
+		public string InReplyToId { get; set; }
+		public string InReplyToAccountId { get; set; }
+		public Status Reblog { get; set; }
+		public string Content { get; set; } = string.Empty;
+		public string CreatedAt { get; set; }
+		public string EditedAt { get; set; }
+		public List<object> Emojis { get; set; } = new();
+		public int RepliesCount { get; set; }
+		public int ReblogsCount { get; set; }
+		public int FavouritesCount { get; set; }
+		public bool Reblogged { get; set; }
+		public bool Favourited { get; set; }
+		public bool Muted { get; set; }
+		public bool Bookmarked { get; set; }
+		public bool Pinned { get; set; }
+		public bool Sensitive { get; set; }
+		public string SpoilerText { get; set; } = string.Empty;
+		public string Visibility { get; set; }
+		public List<MediaAttachment> MediaAttachments { get; set; } = new();
+		public List<StatusMention> Mentions { get; set; } = new();
+		public List<StatusTag> Tags { get; set; } = new();
+		public object Card { get; set; }
+		public object Poll { get; set; }
+		public Application Application { get; set; }
+		public string Language { get; set; }
+		public string Text { get; set; }
+		public List<object> Filtered { get; set; } = new();
+	}
+
+	public class MediaAttachment
+	{
+		public string Id { get; set; }
+		public string Type { get; set; }
+		public string Url { get; set; }
+		public string PreviewUrl { get; set; }
+		public string RemoteUrl { get; set; }
+		public object Meta { get; set; }
+		public string Description { get; set; }
+		public string Blurhash { get; set; }
+	}
+
+	public class StatusMention
+	{
+		public string Id { get; set; }
+		public string Username { get; set; }
+		public string Url { get; set; }
+		public string Acct { get; set; }
+	}
+
+	public class StatusTag
+	{
+		public string Name { get; set; }
+		public string Url { get; set; }
+	}
+
+	public class Application
+	{
+		public string Id { get; set; }
+		public string Name { get; set; }
+		public string Website { get; set; }
+		public List<string> Scopes { get; set; } = new();
+		public List<string> RedirectUris { get; set; } = new();
+		public string RedirectUri { get; set; }
+		public string ClientId { get; set; }
+		public string ClientSecret { get; set; }
+		public string VapidKey { get; set; } = string.Empty;
+	}
+
+	public class Relationship
+	{
+		public string Id { get; set; }
+		public bool Following { get; set; }
+		public bool ShowingReblogs { get; set; }
+		public bool Notifying { get; set; }
+		public List<string> Languages { get; set; }
+		public bool FollowedBy { get; set; }
+		public bool Blocking { get; set; }
+		public bool BlockedBy { get; set; }
+		public bool Muting { get; set; }
+		public bool MutingNotifications { get; set; }
+		public bool Requested { get; set; }
+		public bool RequestedBy { get; set; }
+		public bool DomainBlocking { get; set; }
+		public bool Endorsed { get; set; }
+		public string Note { get; set; } = string.Empty;
+	}
+
+	public class Notification
+	{
+		public string Id { get; set; }
+		public string Type { get; set; }
+		public string CreatedAt { get; set; }
+		public string GroupKey { get; set; }
+		public Account Account { get; set; }
+		public Status Status { get; set; }
+	}
+
+	public class Context
+	{
+		public List<Status> Ancestors { get; set; } = new();
+		public List<Status> Descendants { get; set; } = new();
+	}
+
+	public class StatusEdit
+	{
+		public string Content { get; set; }
+		public string SpoilerText { get; set; }
+		public bool Sensitive { get; set; }
+		public string CreatedAt { get; set; }
+		public Account Account { get; set; }
+		public List<MediaAttachment> MediaAttachments { get; set; } = new();
+		public List<object> Emojis { get; set; } = new();
+	}
+
+	public class StatusSource
+	{
+		public string Id { get; set; }
+		public string Text { get; set; }
+		public string SpoilerText { get; set; }
+	}
+
+	public class SearchResults
+	{
+		public List<Account> Accounts { get; set; } = new();
+		public List<Status> Statuses { get; set; } = new();
+		public List<object> Hashtags { get; set; } = new();
+	}
+
+	public class Conversation
+	{
+		public string Id { get; set; }
+		public bool Unread { get; set; }
+		public List<Account> Accounts { get; set; } = new();
+		public Status LastStatus { get; set; }
+	}
+
+	public class Marker
+	{
+		public string LastReadId { get; set; }
+		public int Version { get; set; }
+		public string UpdatedAt { get; set; }
+	}
+}

PrivaPub/Api/Mastodon/Infrastructure/MastodonController.cs

@@ -0,0 +1,105 @@
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.Filters;
+
+using MongoDB.Entities;
+
+using OpenIddict.Abstractions;
+using OpenIddict.Validation.AspNetCore;
+
+using PrivaPub.Api.Mastodon.Auth;
+using PrivaPub.Federation.Actors;
+using PrivaPub.Models.Federation;
+using PrivaPub.Models.User;
+using PrivaPub.StaticServices;
+
+using static OpenIddict.Abstractions.OpenIddictConstants;
+
+namespace PrivaPub.Api.Mastodon.Infrastructure
+{
+	[AttributeUsage(AttributeTargets.Method | AttributeTargets.Class)]
+	public sealed class ScopeAttribute : Attribute
+	{
+		public ScopeAttribute(string scope, bool requiresUser = true)
+		{
+			Scope = scope;
+			RequiresUser = requiresUser;
+		}
+
+		public string Scope { get; }
+		public bool RequiresUser { get; }
+	}
+
+	[ApiController, Authorize(AuthenticationSchemes = OpenIddictValidationAspNetCoreDefaults.AuthenticationScheme)]
+	public abstract class MastodonController : ControllerBase, IAsyncActionFilter
+	{
+		MastodonParams _params;
+
+		protected LocalActor Me { get; private set; }
+
+		protected string MyId => Me?.Id;
+
+		protected MastodonParams Params => _params;
+
+		[NonAction]
+		public async Task OnActionExecutionAsync(ActionExecutingContext context, ActionExecutionDelegate next)
+		{
+			_params = await MastodonParams.Read(Request, HttpContext.RequestAborted);
+			var scope = context.ActionDescriptor.EndpointMetadata.OfType<ScopeAttribute>().LastOrDefault();
+			if (User.Identity?.IsAuthenticated == true)
+			{
+				if (scope != default && !MastodonScopes.Grants(User.GetScopes(), scope.Scope))
+				{
+					context.Result = Error(StatusCodes.Status403Forbidden, "This action is outside the authorized scopes");
+					return;
+				}
+				Me = await Resolve(User.GetClaim(Claims.Subject), HttpContext.RequestAborted);
+			}
+			if (scope?.RequiresUser == true && Me == default)
+			{
+				context.Result = Error(StatusCodes.Status401Unauthorized, "This method requires an authenticated user");
+				return;
+			}
+			await next();
+		}
+
+		async Task<LocalActor> Resolve(string avatarId, CancellationToken token)
+		{
+			if (string.IsNullOrEmpty(avatarId))
+				return default;
+			var services = HttpContext.RequestServices;
+			var db = services.GetRequiredService<DbEntities>();
+			var link = await db.RootToAvatars.Match(r => r.AvatarId == avatarId).ExecuteFirstAsync(token);
+			if (link == default)
+				return default;
+			var root = await db.RootUsers.MatchID(link.RootId).ExecuteFirstAsync(token);
+			if (root is not { IsBanned: false, DeletedAt: null })
+				return default;
+			return await services.GetRequiredService<ILocalActorService>().FindById(LocalActorKind.Person, avatarId, token);
+		}
+
+		protected JsonResult Json(object value, int status = StatusCodes.Status200OK) =>
+			new(value, MastodonJson.Options) { StatusCode = status };
+
+		protected static JsonResult Error(int status, string message) =>
+			new(new { error = message }, MastodonJson.Options) { StatusCode = status };
+
+		protected JsonResult NotFoundError() => Error(StatusCodes.Status404NotFound, "Record not found");
+
+		protected void Link(string path, string maxId, string minId)
+		{
+			var links = new List<string>();
+			var baseUrl = $"{Request.Scheme}://{Request.Host}{path}";
+			var query = Request.Query.Where(q => q.Key is not ("max_id" or "min_id" or "since_id")).Select(q => $"{q.Key}={Uri.EscapeDataString(q.Value.ToString())}").ToList();
+			string With(string key, string value) => baseUrl + "?" + string.Join("&", query.Append($"{key}={value}"));
+			if (maxId != default)
+				links.Add($"<{With("max_id", maxId)}>; rel=\"next\"");
+			if (minId != default)
+				links.Add($"<{With("min_id", minId)}>; rel=\"prev\"");
+			if (links.Count > 0)
+				Response.Headers["Link"] = string.Join(", ", links);
+		}
+
+		protected int Limit(int fallback = 20, int max = 40) => Math.Clamp(Params.Int("limit") ?? fallback, 1, max);
+	}
+}

PrivaPub/Api/Mastodon/Infrastructure/MastodonJson.cs

@@ -0,0 +1,24 @@
+using System.Text.Encodings.Web;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace PrivaPub.Api.Mastodon.Infrastructure
+{
+	public static class MastodonJson
+	{
+		public static readonly JsonSerializerOptions Options = new()
+		{
+			PropertyNamingPolicy = JsonNamingPolicy.SnakeCaseLower,
+			DictionaryKeyPolicy = default,
+			DefaultIgnoreCondition = JsonIgnoreCondition.Never,
+			Encoder = JavaScriptEncoder.UnsafeRelaxedJsonEscaping,
+			Converters = { new JsonStringEnumConverter(JsonNamingPolicy.SnakeCaseLower) }
+		};
+
+		public static string Time(DateTime value) =>
+			DateTime.SpecifyKind(value, DateTimeKind.Utc).ToString("yyyy-MM-ddTHH:mm:ss.fffZ", System.Globalization.CultureInfo.InvariantCulture);
+
+		public static string Day(DateTime value) =>
+			DateTime.SpecifyKind(value, DateTimeKind.Utc).Date.ToString("yyyy-MM-ddT00:00:00.000Z", System.Globalization.CultureInfo.InvariantCulture);
+	}
+}

PrivaPub/Api/Mastodon/Infrastructure/MastodonParams.cs

@@ -0,0 +1,109 @@
+using Microsoft.AspNetCore.Http.Features;
+
+using System.Text.Json;
+
+namespace PrivaPub.Api.Mastodon.Infrastructure
+{
+	public sealed class MastodonParams
+	{
+		readonly Dictionary<string, List<string>> _values;
+
+		MastodonParams(Dictionary<string, List<string>> values)
+		{
+			_values = values;
+		}
+
+		public static async Task<MastodonParams> Read(HttpRequest request, CancellationToken token)
+		{
+			var values = new Dictionary<string, List<string>>(StringComparer.Ordinal);
+			foreach (var pair in request.Query)
+				foreach (var value in pair.Value)
+					Add(values, pair.Key, value);
+
+			if (request.HasFormContentType)
+			{
+				var form = await request.ReadFormAsync(token);
+				foreach (var pair in form)
+					foreach (var value in pair.Value)
+						Add(values, pair.Key, value);
+			}
+			else if (request.ContentType?.Contains("json", StringComparison.OrdinalIgnoreCase) == true && request.ContentLength != 0)
+			{
+				try
+				{
+					using var document = await JsonDocument.ParseAsync(request.Body, cancellationToken: token);
+					Flatten(values, default, document.RootElement);
+				}
+				catch (JsonException)
+				{
+				}
+			}
+			return new MastodonParams(values);
+		}
+
+		public static MastodonParams From(IEnumerable<KeyValuePair<string, string>> pairs)
+		{
+			var values = new Dictionary<string, List<string>>(StringComparer.Ordinal);
+			foreach (var pair in pairs)
+				Add(values, pair.Key, pair.Value);
+			return new MastodonParams(values);
+		}
+
+		public bool Has(string name) => _values.ContainsKey(name);
+
+		public string Get(string name) => _values.TryGetValue(name, out var list) && list.Count > 0 ? list[^1] : default;
+
+		public IReadOnlyList<string> List(string name) => _values.TryGetValue(name, out var list) ? list : (IReadOnlyList<string>)Array.Empty<string>();
+
+		public bool? Bool(string name) => Get(name)?.ToLowerInvariant() switch
+		{
+			"true" or "1" or "on" or "yes" => true,
+			"false" or "0" or "off" or "no" or "" => false,
+			_ => (bool?)null
+		};
+
+		public int? Int(string name) => int.TryParse(Get(name), out var value) ? value : (int?)null;
+
+		static void Add(Dictionary<string, List<string>> values, string key, string value)
+		{
+			key = key.EndsWith("[]", StringComparison.Ordinal) ? key[..^2] : key;
+			if (!values.TryGetValue(key, out var list))
+				values[key] = list = new List<string>();
+			list.Add(value);
+		}
+
+		static void Flatten(Dictionary<string, List<string>> values, string prefix, JsonElement element)
+		{
+			switch (element.ValueKind)
+			{
+				case JsonValueKind.Object:
+					foreach (var property in element.EnumerateObject())
+						Flatten(values, prefix == default ? property.Name : $"{prefix}[{property.Name}]", property.Value);
+					break;
+				case JsonValueKind.Array:
+					foreach (var item in element.EnumerateArray())
+					{
+						if (item.ValueKind is JsonValueKind.Object or JsonValueKind.Array)
+							Flatten(values, prefix + "[]", item);
+						else
+							Add(values, prefix, Scalar(item));
+					}
+					break;
+				case JsonValueKind.Null or JsonValueKind.Undefined:
+					break;
+				default:
+					if (prefix != default)
+						Add(values, prefix, Scalar(element));
+					break;
+			}
+		}
+
+		static string Scalar(JsonElement element) => element.ValueKind switch
+		{
+			JsonValueKind.String => element.GetString(),
+			JsonValueKind.True => "true",
+			JsonValueKind.False => "false",
+			_ => element.GetRawText()
+		};
+	}
+}

PrivaPub/Api/Mastodon/Infrastructure/Paging.cs

@@ -0,0 +1,30 @@
+using MongoDB.Driver;
+using MongoDB.Entities;
+
+using System.Linq.Expressions;
+
+namespace PrivaPub.Api.Mastodon.Infrastructure
+{
+	public sealed record Page(string MaxId, string SinceId, string MinId, int Limit)
+	{
+		public static Page From(MastodonParams parameters, int limit) =>
+			new(parameters.Get("max_id"), parameters.Get("since_id"), parameters.Get("min_id"), limit);
+
+		public async Task<List<T>> Fetch<T>(Find<T, T> query, Expression<Func<T, string>> id, CancellationToken token) where T : IEntity
+		{
+			var field = new ExpressionFieldDefinition<T, string>(id);
+			if (!string.IsNullOrEmpty(MaxId))
+				query.Match(Builders<T>.Filter.Lt(field, MaxId));
+			if (!string.IsNullOrEmpty(SinceId))
+				query.Match(Builders<T>.Filter.Gt(field, SinceId));
+			if (!string.IsNullOrEmpty(MinId))
+				query.Match(Builders<T>.Filter.Gt(field, MinId));
+			var ascending = !string.IsNullOrEmpty(MinId);
+			var sortField = new ExpressionFieldDefinition<T>(Expression.Lambda<Func<T, object>>(Expression.Convert(id.Body, typeof(object)), id.Parameters));
+			var items = await query.Sort(s => ascending ? s.Ascending(sortField) : s.Descending(sortField)).Limit(Limit).ExecuteAsync(token);
+			if (ascending)
+				items.Reverse();
+			return items;
+		}
+	}
+}

PrivaPub/Api/Mastodon/Mappers/AccountSearch.cs

@@ -0,0 +1,55 @@
+using PrivaPub.Api.Mastodon.Entities;
+using PrivaPub.Federation.Actors;
+using PrivaPub.StaticServices;
+
+namespace PrivaPub.Api.Mastodon.Mappers
+{
+	public class AccountSearch
+	{
+		readonly MastodonMapper _mapper;
+		readonly DbEntities _dbEntities;
+		readonly ILocalActorService _localActors;
+		readonly IRemoteActorService _remoteActors;
+
+		public AccountSearch(MastodonMapper mapper, DbEntities dbEntities, ILocalActorService localActors, IRemoteActorService remoteActors)
+		{
+			_mapper = mapper;
+			_dbEntities = dbEntities;
+			_localActors = localActors;
+			_remoteActors = remoteActors;
+		}
+
+		public async Task<List<Account>> Find(string q, bool resolve, int limit, CancellationToken token)
+		{
+			q = q?.Trim().TrimStart('@');
+			if (string.IsNullOrEmpty(q))
+				return new List<Account>();
+			var results = new List<Account>();
+			var parts = q.Split('@');
+			var localDomain = new Uri(_localActors.BaseAddress).Authority;
+			if (parts.Length == 2 && !parts[1].Equals(localDomain, StringComparison.OrdinalIgnoreCase) && !string.IsNullOrEmpty(parts[0]))
+			{
+				var userName = parts[0];
+				var domain = parts[1].ToLowerInvariant();
+				var known = await _dbEntities.ForeignAvatars.Match(f => f.UserName == userName && f.Domain == domain).ExecuteFirstAsync(token);
+				if (known == default && resolve)
+				{
+					var actorUri = await _remoteActors.ResolveHandle(q, token);
+					known = actorUri == default ? default : await _remoteActors.GetActor(actorUri, refresh: false, token);
+				}
+				if (known != default)
+					results.Add(_mapper.Foreign(known));
+				return results;
+			}
+
+			var prefix = parts[0].ToLowerInvariant();
+			foreach (var avatar in await _dbEntities.Avatars.Match(a => a.UserName.StartsWith(prefix) && !a.DeletionAt.HasValue && a.Settings.IsDiscoverable != false)
+				.Limit(limit).ExecuteAsync(token))
+				results.Add(await _mapper.Local(_localActors.FromAvatar(avatar), false, token));
+			foreach (var foreign in await _dbEntities.ForeignAvatars.Match(f => f.UserName.StartsWith(parts[0]) && f.IsDiscoverable)
+				.Limit(Math.Max(0, limit - results.Count)).ExecuteAsync(token))
+				results.Add(_mapper.Foreign(foreign));
+			return results;
+		}
+	}
+}

PrivaPub/Api/Mastodon/Mappers/MastodonMapper.cs

@@ -0,0 +1,256 @@
+using MongoDB.Entities;
+
+using PrivaPub.Api.Mastodon.Entities;
+using PrivaPub.Api.Mastodon.Infrastructure;
+using PrivaPub.Federation.Actors;
+using PrivaPub.Federation.Rendering;
+using PrivaPub.Models.Federation;
+using PrivaPub.Models.Post;
+using PrivaPub.Models.Social;
+using PrivaPub.Models.User;
+using PrivaPub.StaticServices;
+
+using System.Net;
+
+using GroupEntity = PrivaPub.Models.Group.Group;
+using PostEntity = PrivaPub.Models.Post.Post;
+
+namespace PrivaPub.Api.Mastodon.Mappers
+{
+	public class MastodonMapper
+	{
+		readonly DbEntities _dbEntities;
+		readonly ILocalActorService _localActors;
+
+		public MastodonMapper(DbEntities dbEntities, ILocalActorService localActors)
+		{
+			_dbEntities = dbEntities;
+			_localActors = localActors;
+		}
+
+		string MissingAvatar => $"{_localActors.BaseAddress}/media/missing-avatar.png";
+		string MissingHeader => $"{_localActors.BaseAddress}/media/missing-header.png";
+
+		public async Task<Account> Local(LocalActor actor, bool withSource, CancellationToken token)
+		{
+			var followers = await DB.Default.CountAsync<Follower>(f => f.LocalActorId == actor.Id && f.LocalActorKind == actor.Kind && f.IsAccepted, token);
+			var following = actor.Kind == LocalActorKind.Person
+				? await DB.Default.CountAsync<Following>(f => f.AvatarId == actor.Id && f.State == FollowState.Accepted, token)
+				: 0;
+			var latest = await _dbEntities.Posts
+				.Match(p => (actor.Kind == LocalActorKind.Group ? p.GroupId == actor.Id : p.GroupUserId == actor.Id) && !p.IsFederatedCopy
+					&& !p.DeletedAt.HasValue && p.Visibility != PostVisibility.Direct && p.ReblogOfPostId == null)
+				.Sort(p => p.ID, Order.Descending)
+				.Limit(1)
+				.ExecuteFirstAsync(token);
+			var statuses = latest == default
+				? 0
+				: await DB.Default.CountAsync<PostEntity>(p => (actor.Kind == LocalActorKind.Group ? p.GroupId == actor.Id : p.GroupUserId == actor.Id)
+					&& !p.IsFederatedCopy && !p.DeletedAt.HasValue && p.Visibility != PostVisibility.Direct && p.ReblogOfPostId == null, token);
+
+			var account = new Account
+			{
+				Id = actor.Id,
+				Username = actor.UserName,
+				Acct = actor.UserName,
+				DisplayName = actor.Name ?? actor.UserName,
+				Locked = actor.ManuallyApprovesFollowers,
+				Bot = actor.IsBot,
+				Discoverable = actor.Discoverable,
+				Indexable = actor.Indexable,
+				Noindex = !actor.Indexable,
+				HideCollections = actor.Settings.HideCollections,
+				Group = actor.Kind == LocalActorKind.Group,
+				CreatedAt = MastodonJson.Day(actor.Published),
+				Note = ActivityPubRenderer.Html(actor.Summary),
+				Url = actor.HtmlUrl,
+				Uri = actor.Uri,
+				Avatar = actor.PictureURL ?? MissingAvatar,
+				AvatarStatic = actor.PictureURL ?? MissingAvatar,
+				Header = actor.ThumbnailURL ?? MissingHeader,
+				HeaderStatic = actor.ThumbnailURL ?? MissingHeader,
+				FollowersCount = (int)followers,
+				FollowingCount = (int)following,
+				StatusesCount = (int)statuses,
+				LastStatusAt = latest == default ? default : latest.CreationDate.ToString("yyyy-MM-dd"),
+				Fields = actor.Fields.Select(f => new Field { Name = f.Key, Value = ActivityPubRenderer.FieldValue(f.Value) }).ToList()
+			};
+			if (withSource)
+				account.Source = new Source
+				{
+					Privacy = actor.Settings.DefaultVisibility ?? "public",
+					Sensitive = actor.Settings.DefaultSensitive,
+					Language = actor.Settings.DefaultLanguage,
+					Note = actor.Summary ?? string.Empty,
+					Fields = actor.Fields.Select(f => new Field { Name = f.Key, Value = f.Value }).ToList(),
+					FollowRequestsCount = (int)await DB.Default.CountAsync<Follower>(f => f.LocalActorId == actor.Id && !f.IsAccepted, token)
+				};
+			return account;
+		}
+
+		public Account Foreign(ForeignAvatar foreign) => new()
+		{
+			Id = foreign.ID,
+			Username = foreign.UserName,
+			Acct = $"{foreign.UserName}@{foreign.Domain}",
+			DisplayName = foreign.Name ?? foreign.UserName ?? string.Empty,
+			Bot = foreign.AvatarType is AvatarType.Service or AvatarType.Application,
+			Group = foreign.AvatarType == AvatarType.Group,
+			Discoverable = foreign.IsDiscoverable,
+			CreatedAt = MastodonJson.Day(foreign.CreatedAt),
+			Note = foreign.Biography ?? string.Empty,
+			Url = foreign.Url ?? foreign.ActorURI,
+			Uri = foreign.ActorURI,
+			Avatar = foreign.PictureURL ?? MissingAvatar,
+			AvatarStatic = foreign.PictureURL ?? MissingAvatar,
+			Header = foreign.ThumbnailURL ?? MissingHeader,
+			HeaderStatic = foreign.ThumbnailURL ?? MissingHeader
+		};
+
+		public async Task<Account> Account(string id, CancellationToken token) =>
+			(await Accounts(new[] { id }, token)).GetValueOrDefault(id);
+
+		public async Task<Dictionary<string, Account>> Accounts(IEnumerable<string> ids, CancellationToken token)
+		{
+			var wanted = ids.Where(id => !string.IsNullOrEmpty(id)).Distinct().ToList();
+			var accounts = new Dictionary<string, Account>();
+			if (wanted.Count == 0)
+				return accounts;
+
+			foreach (var avatar in await _dbEntities.Avatars.Match(a => wanted.Contains(a.ID) && !a.DeletionAt.HasValue).ExecuteAsync(token))
+				accounts[avatar.ID] = await Local(_localActors.FromAvatar(avatar), false, token);
+			foreach (var group in await _dbEntities.Groups.Match(g => wanted.Contains(g.ID) && !g.DeletionAt.HasValue).ExecuteAsync(token))
+				accounts[group.ID] = await Local(_localActors.FromGroup(group), false, token);
+			foreach (var foreign in await _dbEntities.ForeignAvatars.Match(f => wanted.Contains(f.ID)).ExecuteAsync(token))
+				accounts[foreign.ID] = Foreign(foreign);
+			return accounts;
+		}
+
+		public async Task<Status> Status(PostEntity post, string viewerId, CancellationToken token) =>
+			(await Statuses(new[] { post }, viewerId, token)).FirstOrDefault();
+
+		public async Task<List<Status>> Statuses(IReadOnlyCollection<PostEntity> posts, string viewerId, CancellationToken token)
+		{
+			var originalIds = posts.Where(p => p.ReblogOfPostId != default).Select(p => p.ReblogOfPostId).Distinct().ToList();
+			var originals = originalIds.Count == 0
+				? new Dictionary<string, PostEntity>()
+				: (await _dbEntities.Posts.Match(p => originalIds.Contains(p.ID) && !p.DeletedAt.HasValue).ExecuteAsync(token)).ToDictionary(p => p.ID);
+			var all = posts.Concat(originals.Values).ToList();
+
+			var mentionUris = all.SelectMany(p => p.Mentions).Where(m => !m.IsLocal).Select(m => m.ActorURI).Distinct().ToList();
+			var mentionAccounts = mentionUris.Count == 0
+				? new Dictionary<string, ForeignAvatar>()
+				: (await _dbEntities.ForeignAvatars.Match(f => mentionUris.Contains(f.ActorURI)).ExecuteAsync(token)).ToDictionary(f => f.ActorURI);
+			var accounts = await Accounts(all.Select(AuthorOf), token);
+
+			var ids = all.Select(p => p.ID).ToList();
+			var favourited = viewerId == default
+				? new HashSet<string>()
+				: (await _dbEntities.Favourites.Match(f => f.AccountId == viewerId && ids.Contains(f.PostId)).ExecuteAsync(token)).Select(f => f.PostId).ToHashSet();
+			var reblogged = viewerId == default
+				? new HashSet<string>()
+				: (await _dbEntities.Posts.Match(p => p.AuthorAccountId == viewerId && ids.Contains(p.ReblogOfPostId) && !p.DeletedAt.HasValue).ExecuteAsync(token))
+					.Select(p => p.ReblogOfPostId).ToHashSet();
+
+			Status Map(PostEntity post)
+			{
+				if (!accounts.TryGetValue(AuthorOf(post), out var account))
+					return default;
+				var status = new Status
+				{
+					Id = post.ID,
+					Uri = post.ObjectURI,
+					Url = post.Url ?? post.ObjectURI,
+					Account = account,
+					InReplyToId = post.AnsweringToPostId,
+					InReplyToAccountId = post.InReplyToAccountId,
+					Content = Content(post),
+					CreatedAt = MastodonJson.Time(post.CreationDate),
+					EditedAt = post.EditedAt.HasValue ? MastodonJson.Time(post.EditedAt.Value) : default,
+					RepliesCount = post.RepliesCount,
+					ReblogsCount = post.ReblogsCount,
+					FavouritesCount = post.FavouritesCount,
+					Favourited = favourited.Contains(post.ID),
+					Reblogged = reblogged.Contains(post.ID),
+					Sensitive = post.HasContentWarning,
+					SpoilerText = post.SpoilerText ?? (post.HasContentWarning ? post.Title ?? ActivityPubRenderer.ContentWarning : string.Empty),
+					Visibility = Visibility(post.Visibility),
+					Language = post.Language,
+					MediaAttachments = post.Media.Select(Media).ToList(),
+					Mentions = post.Mentions.Select(m => Mention(m, mentionAccounts)).Where(m => m != default).ToList(),
+					Tags = post.Tags.Select(t => new StatusTag { Name = t, Url = ActivityPubRenderer.TagUrl(_localActors.BaseAddress, t) }).ToList()
+				};
+				return status;
+			}
+
+			var mapped = new List<Status>();
+			foreach (var post in posts)
+			{
+				var status = Map(post);
+				if (status == default)
+					continue;
+				if (post.ReblogOfPostId != default)
+				{
+					if (!originals.TryGetValue(post.ReblogOfPostId, out var original) || Map(original) is not { } inner)
+						continue;
+					status.Reblog = inner;
+					status.Content = string.Empty;
+					status.Reblogged = reblogged.Contains(original.ID);
+				}
+				mapped.Add(status);
+			}
+			return mapped;
+		}
+
+		public static string AuthorOf(PostEntity post) => post.AuthorAccountId ?? post.GroupUserId;
+
+		public static string Content(PostEntity post)
+		{
+			var content = post.ContentHtml ?? ActivityPubRenderer.Html(post.Text);
+			return string.IsNullOrEmpty(post.Title) || post.IsFederatedCopy
+				? content ?? string.Empty
+				: $"<p><strong>{WebUtility.HtmlEncode(post.Title)}</strong></p>{content}";
+		}
+
+		public static string Visibility(PostVisibility visibility) => visibility switch
+		{
+			PostVisibility.Unlisted => "unlisted",
+			PostVisibility.FollowersOnly or PostVisibility.Circle => "private",
+			PostVisibility.Direct => "direct",
+			_ => "public"
+		};
+
+		StatusMention Mention(PostMention mention, IReadOnlyDictionary<string, ForeignAvatar> foreign)
+		{
+			if (mention.IsLocal)
+			{
+				var handle = mention.Handle?.TrimStart('@').Split('@')[0];
+				return new StatusMention { Id = mention.AccountId, Username = handle, Acct = handle, Url = mention.ActorURI };
+			}
+			if (!foreign.TryGetValue(mention.ActorURI, out var account))
+				return default;
+			return new StatusMention { Id = account.ID, Username = account.UserName, Acct = $"{account.UserName}@{account.Domain}", Url = account.Url ?? account.ActorURI };
+		}
+
+		static MediaAttachment Media(PostMedia media) => new()
+		{
+			Id = media.Id.ToString("N"),
+			Type = media.ContentType switch
+			{
+				{ } type when type.StartsWith("image/gif") => "gifv",
+				{ } type when type.StartsWith("image/") => "image",
+				{ } type when type.StartsWith("video/") => "video",
+				{ } type when type.StartsWith("audio/") => "audio",
+				_ => "unknown"
+			},
+			Url = media.URL ?? media.RemoteURL,
+			PreviewUrl = media.URL ?? media.RemoteURL,
+			RemoteUrl = media.RemoteURL,
+			Description = media.Description,
+			Blurhash = media.Blurhash,
+			Meta = media.Width.HasValue && media.Height.HasValue
+				? new { original = new { width = media.Width, height = media.Height, aspect = (double)media.Width / media.Height.Value } }
+				: default
+		};
+	}
+}

PrivaPub/Domain/Social/FollowService.cs

@@ -26,6 +26,9 @@ namespace PrivaPub.Domain.Social
 		Task<WebResult> Follow(string rootUserId, FollowForm form, CancellationToken token);
 		Task<WebResult> Unfollow(string rootUserId, FollowForm form, CancellationToken token);
 		Task<WebResult> Followings(string rootUserId, string avatarId, CancellationToken token);
+		Task<Following> FollowAs(LocalActor follower, string target, bool showReblogs, CancellationToken token);
+		Task UnfollowAs(LocalActor follower, string target, CancellationToken token);
+		Task<bool> Decide(LocalActor me, string followerAccountId, bool accept, CancellationToken token);
 	}
 
 	public class FollowService : IFollowService
@@ -56,47 +59,9 @@ namespace PrivaPub.Domain.Social
 				var follower = await OwnedAvatar(rootUserId, form.AvatarId, token);
 				if (follower == default)
 					return result.Invalidate(_localizer["Avatar not found."], StatusCodes.Status404NotFound);
-
+				var following = await FollowAs(follower, form.Target, true, token);
-				var (local, remote) = await ResolveTarget(form.Target, token);
+				if (following == default)
-				if (local == default && remote == default)
 					return result.Invalidate(_localizer["Account not found."], StatusCodes.Status404NotFound);
-				if (local != default && (local.Id == follower.Id || !local.IsFederated || local.Kind == LocalActorKind.Application))
-					return result.Invalidate(_localizer["Account not found."], StatusCodes.Status404NotFound);
-
-				var targetUri = local?.Uri ?? remote.ActorURI;
-				var existing = await _dbEntities.Followings.Match(f => f.AvatarId == follower.Id && f.TargetActorURI == targetUri).ExecuteFirstAsync(token);
-				if (existing != default)
-				{
-					result.Data = ToView(existing);
-					return result;
-				}
-
-				var following = new Following
-				{
-					AvatarId = follower.Id,
-					TargetActorURI = targetUri,
-					TargetAccountId = local?.Id ?? remote.ID,
-					TargetIsLocal = local != default,
-					TargetInboxURL = local?.Inbox ?? remote.InboxURL,
-					State = local is { ManuallyApprovesFollowers: false } ? FollowState.Accepted : FollowState.Requested
-				};
-				following.ID = (string)following.GenerateNewID();
-				following.FollowActivityURI = follower.ActivityUri($"follow-{following.ID}");
-				try
-				{
-					await DB.Default.SaveAsync(following, token);
-				}
-				catch (MongoWriteException ex) when (ex.WriteError?.Category == ServerErrorCategory.DuplicateKey)
-				{
-					result.Data = ToView(await _dbEntities.Followings.Match(f => f.AvatarId == follower.Id && f.TargetActorURI == targetUri).ExecuteFirstAsync(token));
-					return result;
-				}
-
-				if (local != default)
-					await FollowLocally(follower, local, following, token);
-				else
-					await _delivery.Enqueue(follower, new[] { remote.InboxURL }, FollowActivity(follower, following), token);
-
 				result.Data = ToView(following);
 				return result;
 			}
@@ -115,12 +80,69 @@ namespace PrivaPub.Domain.Social
 				var follower = await OwnedAvatar(rootUserId, form.AvatarId, token);
 				if (follower == default)
 					return result.Invalidate(_localizer["Avatar not found."], StatusCodes.Status404NotFound);
+				await UnfollowAs(follower, form.Target, token);
+				return result;
+			}
+			catch (Exception ex)
+			{
+				_logger.LogError(ex, $"{nameof(FollowService)}.{nameof(Unfollow)}");
+				return result.Invalidate(_localizer["Something went wrong."], exception: ex);
+			}
+		}
 
-				var (local, remote) = await ResolveTarget(form.Target, token);
+		public async Task<Following> FollowAs(LocalActor follower, string target, bool showReblogs, CancellationToken token)
-				var targetUri = local?.Uri ?? remote?.ActorURI ?? form.Target;
+		{
+			var (local, remote) = await ResolveTarget(target, token);
+			if (local == default && remote == default)
+				return default;
+			if (local != default && (local.Id == follower.Id || !local.IsFederated || local.Kind == LocalActorKind.Application))
+				return default;
+
+			var targetUri = local?.Uri ?? remote.ActorURI;
+			var existing = await _dbEntities.Followings.Match(f => f.AvatarId == follower.Id && f.TargetActorURI == targetUri).ExecuteFirstAsync(token);
+			if (existing != default)
+			{
+				if (existing.ShowReblogs != showReblogs)
+					await DB.Default.Update<Following>().MatchID(existing.ID).Modify(f => f.ShowReblogs, showReblogs).ExecuteAsync(token);
+				existing.ShowReblogs = showReblogs;
+				return existing;
+			}
+
+			var following = new Following
+			{
+				AvatarId = follower.Id,
+				TargetActorURI = targetUri,
+				TargetAccountId = local?.Id ?? remote.ID,
+				TargetIsLocal = local != default,
+				TargetInboxURL = local?.Inbox ?? remote.InboxURL,
+				ShowReblogs = showReblogs,
+				State = local is { ManuallyApprovesFollowers: false } ? FollowState.Accepted : FollowState.Requested
+			};
+			following.ID = (string)following.GenerateNewID();
+			following.FollowActivityURI = follower.ActivityUri($"follow-{following.ID}");
+			try
+			{
+				await DB.Default.SaveAsync(following, token);
+			}
+			catch (MongoWriteException ex) when (ex.WriteError?.Category == ServerErrorCategory.DuplicateKey)
+			{
+				return await _dbEntities.Followings.Match(f => f.AvatarId == follower.Id && f.TargetActorURI == targetUri).ExecuteFirstAsync(token);
+			}
+
+			if (local != default)
+				await FollowLocally(follower, local, following, token);
+			else
+				await _delivery.Enqueue(follower, new[] { remote.InboxURL }, FollowActivity(follower, following), token);
+			return following;
+		}
+
+		public async Task UnfollowAs(LocalActor follower, string target, CancellationToken token)
+		{
+			var (local, remote) = await ResolveTarget(target, token);
+			var targetUri = local?.Uri ?? remote?.ActorURI ?? target;
 			var following = await _dbEntities.Followings.Match(f => f.AvatarId == follower.Id && f.TargetActorURI == targetUri).ExecuteFirstAsync(token);
 			if (following == default)
-					return result;
+				return;
 
 			await DB.Default.DeleteAsync<Following>(following.ID);
 			if (following.TargetIsLocal)
@@ -129,9 +151,8 @@ namespace PrivaPub.Domain.Social
 				await DB.Default.Update<GroupEntity>().MatchID(following.TargetAccountId)
 					.Modify(b => b.PullFilter(g => g.Members, m => !m.IsForeign && m.AvatarId == follower.Id && m.Role == GroupRole.Member))
 					.ExecuteAsync(token);
+				return;
 			}
-				else
-				{
 			var undo = new JsonObject
 			{
 				["@context"] = ActivityPubRenderer.ActivityStreams,
@@ -142,13 +163,56 @@ namespace PrivaPub.Domain.Social
 			};
 			await _delivery.Enqueue(follower, new[] { following.TargetInboxURL }, undo, token);
 		}
-				return result;
+
-			}
+		public async Task<bool> Decide(LocalActor me, string followerAccountId, bool accept, CancellationToken token)
-			catch (Exception ex)
 		{
-				_logger.LogError(ex, $"{nameof(FollowService)}.{nameof(Unfollow)}");
+			var localFollower = await _localActors.FindById(LocalActorKind.Person, followerAccountId, token);
-				return result.Invalidate(_localizer["Something went wrong."], exception: ex);
+			var remoteFollower = localFollower == default ? await _dbEntities.ForeignAvatars.MatchID(followerAccountId).ExecuteFirstAsync(token) : default;
+			var followerUri = localFollower?.Uri ?? remoteFollower?.ActorURI;
+			if (followerUri == default)
+				return false;
+			var request = await _dbEntities.Followers.Match(f => f.LocalActorId == me.Id && f.LocalActorKind == me.Kind && f.ActorURI == followerUri && !f.IsAccepted)
+				.ExecuteFirstAsync(token);
+			if (request == default)
+				return false;
+
+			if (accept)
+				await DB.Default.Update<Follower>().MatchID(request.ID).Modify(f => f.IsAccepted, true).ExecuteAsync(token);
+			else
+				await DB.Default.DeleteAsync<Follower>(request.ID);
+
+			if (localFollower != default)
+			{
+				if (accept)
+					await DB.Default.Update<Following>().Match(f => f.AvatarId == localFollower.Id && f.TargetActorURI == me.Uri)
+						.Modify(f => f.State, FollowState.Accepted).ExecuteAsync(token);
+				else
+					await DB.Default.DeleteAsync<Following>(f => f.AvatarId == localFollower.Id && f.TargetActorURI == me.Uri);
 			}
+			else
+			{
+				var follow = new JsonObject
+				{
+					["id"] = request.FollowActivityURI,
+					["type"] = "Follow",
+					["actor"] = followerUri,
+					["object"] = me.Uri
+				};
+				var answer = accept
+					? ActivityPubRenderer.Accept(me, follow, $"accept-{request.ID}-{DateTime.UtcNow.Ticks}")
+					: new JsonObject
+					{
+						["@context"] = ActivityPubRenderer.ActivityStreams,
+						["id"] = me.ActivityUri($"reject-{request.ID}-{DateTime.UtcNow.Ticks}"),
+						["type"] = "Reject",
+						["actor"] = me.Uri,
+						["object"] = follow
+					};
+				await _delivery.Enqueue(me, new[] { request.InboxURL }, answer, token);
+			}
+			if (accept)
+				await Notifications.Add(me.Id, NotificationType.Follow, followerAccountId, followerUri, default, token);
+			return true;
 		}
 
 		public async Task<WebResult> Followings(string rootUserId, string avatarId, CancellationToken token)

PrivaPub/Domain/Statuses/StatusService.cs

@@ -0,0 +1,489 @@
+using MongoDB.Driver;
+using MongoDB.Entities;
+
+using PrivaPub.Domain.Content;
+using PrivaPub.Domain.Privacy;
+using PrivaPub.Domain.Social;
+using PrivaPub.Domain.Timelines;
+using PrivaPub.Federation.Actors;
+using PrivaPub.Federation.Outbox;
+using PrivaPub.Federation.Rendering;
+using PrivaPub.Models.Federation;
+using PrivaPub.Models.Group;
+using PrivaPub.Models.Post;
+using PrivaPub.Models.Social;
+using PrivaPub.StaticServices;
+
+using System.Text.Json.Nodes;
+
+using PostEntity = PrivaPub.Models.Post.Post;
+
+namespace PrivaPub.Domain.Statuses
+{
+	public sealed class StatusDraft
+	{
+		public string Text { get; init; }
+		public bool PlainText { get; init; }
+		public string Title { get; init; }
+		public string SpoilerText { get; init; }
+		public bool Sensitive { get; init; }
+		public PostVisibility Visibility { get; init; } = PostVisibility.Public;
+		public string InReplyTo { get; init; }
+		public string GroupId { get; init; }
+		public string Language { get; init; }
+		public string ConversationId { get; init; }
+		public IReadOnlyList<string> Recipients { get; init; } = Array.Empty<string>();
+	}
+
+	public sealed record StatusOutcome(PostEntity Post, int Status = StatusCodes.Status200OK, string Error = default)
+	{
+		public bool Ok => Error == default;
+		public static StatusOutcome Fail(int status, string error) => new(default, status, error);
+	}
+
+	public interface IStatusService
+	{
+		Task<StatusOutcome> Publish(LocalActor author, StatusDraft draft, CancellationToken token);
+		Task<StatusOutcome> Edit(LocalActor author, string postId, StatusDraft draft, CancellationToken token);
+		Task<StatusOutcome> Remove(LocalActor author, string postId, CancellationToken token);
+		Task<StatusOutcome> Favourite(LocalActor me, string postId, bool on, CancellationToken token);
+		Task<StatusOutcome> Reblog(LocalActor me, string postId, bool on, PostVisibility visibility, CancellationToken token);
+	}
+
+	public class StatusService : IStatusService
+	{
+		const int MaxRevisions = 20;
+
+		readonly DbEntities _dbEntities;
+		readonly ILocalActorService _localActors;
+		readonly IRemoteActorService _remoteActors;
+		readonly IDeliveryService _delivery;
+		readonly IContentRenderer _content;
+		readonly IOutboxPublisher _outbox;
+		readonly IFanout _fanout;
+
+		public StatusService(DbEntities dbEntities, ILocalActorService localActors, IRemoteActorService remoteActors, IDeliveryService delivery,
+			IContentRenderer content, IOutboxPublisher outbox, IFanout fanout)
+		{
+			_dbEntities = dbEntities;
+			_localActors = localActors;
+			_remoteActors = remoteActors;
+			_delivery = delivery;
+			_content = content;
+			_outbox = outbox;
+			_fanout = fanout;
+		}
+
+		public async Task<StatusOutcome> Publish(LocalActor author, StatusDraft draft, CancellationToken token)
+		{
+			if (string.IsNullOrWhiteSpace(draft.Text))
+				return StatusOutcome.Fail(StatusCodes.Status422UnprocessableEntity, "Validation failed: Text can't be blank");
+
+			LocalActor group = default;
+			if (!string.IsNullOrEmpty(draft.GroupId))
+			{
+				var groupEntity = await _dbEntities.Groups.MatchID(draft.GroupId).ExecuteFirstAsync(token);
+				if (groupEntity == default || groupEntity.DeletionAt.HasValue || !groupEntity.Members.Any(m => !m.IsForeign && m.AvatarId == author.Id))
+					return StatusOutcome.Fail(StatusCodes.Status404NotFound, "Group not found");
+				group = _localActors.FromGroup(groupEntity);
+			}
+
+			var parent = await Parent(draft.InReplyTo, token);
+			if (!string.IsNullOrEmpty(draft.InReplyTo) && parent == default && !IsRemoteUri(draft.InReplyTo))
+				return StatusOutcome.Fail(StatusCodes.Status404NotFound, "Record not found");
+			if (parent != default && !await VisibilityPolicy.CanSee(parent, author.Id, token))
+				return StatusOutcome.Fail(StatusCodes.Status404NotFound, "Record not found");
+
+			var rendered = draft.PlainText ? await _content.PlainText(draft.Text, token) : await _content.Markdown(draft.Text, token);
+			var isLocalOnly = group is { IsFederated: false };
+			var visibility = isLocalOnly ? PostVisibility.Circle : draft.Visibility is PostVisibility.Circle or PostVisibility.LocalGeo ? PostVisibility.Public : draft.Visibility;
+			var post = new PostEntity
+			{
+				GroupUserId = author.Id,
+				AuthorAccountId = author.Id,
+				GroupId = group?.Id,
+				Visibility = visibility,
+				Title = Clean(draft.Title),
+				SpoilerText = Clean(draft.SpoilerText),
+				HasContentWarning = draft.Sensitive || Clean(draft.SpoilerText) != default,
+				Text = draft.Text,
+				ContentHtml = rendered.Html,
+				ContentFormat = draft.PlainText ? ContentFormat.Plain : ContentFormat.Markdown,
+				Language = Clean(draft.Language),
+				Mentions = rendered.Mentions.Select(ToMention).ToList(),
+				Tags = rendered.Tags.ToList(),
+				AnsweringToPostId = parent?.ID,
+				InReplyToURI = parent?.ObjectURI ?? (IsRemoteUri(draft.InReplyTo) ? draft.InReplyTo : default),
+				InReplyToAccountId = parent?.AuthorAccountId ?? parent?.GroupUserId,
+				IsLocalOnly = isLocalOnly,
+				ActorURI = author.Uri
+			};
+			post.ID = (string)post.GenerateNewID();
+			post.ObjectURI = author.PostUri(post.ID);
+			post.Url = author.PostHtmlUrl(post.ID);
+
+			JsonObject create = default;
+			if (visibility == PostVisibility.Direct)
+			{
+				var conversation = await Conversation(author, draft, rendered.Mentions, token);
+				if (!conversation.Ok)
+					return StatusOutcome.Fail(conversation.Status, conversation.Error);
+				var (dmGroup, recipients) = (conversation.Group, conversation.Recipients);
+				post.ConversationId = dmGroup.ID;
+				post.ContextURI = dmGroup.ConversationURI;
+				post.Mentions = recipients.Select(r => new PostMention { ActorURI = r.Uri, Handle = "@" + r.Handle, IsLocal = r.LocalId != default, AccountId = r.LocalId ?? r.ForeignId })
+					.Concat(post.Mentions)
+					.DistinctBy(m => m.ActorURI)
+					.ToList();
+				var note = ActivityPubRenderer.DirectNote(post, author, recipients.Select(r => (r.Uri, r.Handle)).ToList(), dmGroup.ConversationURI);
+				create = ActivityPubRenderer.Create(author, note, $"create-{post.ID}");
+				post.To = Strings(note["to"]);
+				await DB.Default.Update<DmGroup>().MatchID(dmGroup.ID).Modify(g => g.UpdatedAt, DateTime.UtcNow).ExecuteAsync(token);
+			}
+			else if (!isLocalOnly)
+			{
+				var note = ActivityPubRenderer.Note(post, author, group, post.InReplyToURI);
+				create = ActivityPubRenderer.Create(author, note, $"create-{post.ID}");
+				post.To = Strings(note["to"]);
+				post.Cc = Strings(note["cc"]);
+			}
+			post.ActivityURI = create?["id"]?.GetValue<string>();
+
+			await DB.Default.SaveAsync(post, token);
+			if (parent != default)
+				await DB.Default.Update<PostEntity>().MatchID(parent.ID).Modify(b => b.Inc(p => p.RepliesCount, 1)).ExecuteAsync(token);
+			await _fanout.Distribute(post, token);
+			if (create != default)
+				await _outbox.Publish(author, post, create, token);
+			if (group is { IsFederated: true } && visibility is PostVisibility.Public or PostVisibility.Unlisted)
+				await _delivery.EnqueueToFollowers(group, ActivityPubRenderer.Announce(group, post.ObjectURI, $"announce-{post.ID}"), token);
+			return new StatusOutcome(post);
+		}
+
+		public async Task<StatusOutcome> Edit(LocalActor author, string postId, StatusDraft draft, CancellationToken token)
+		{
+			var post = await Own(author, postId, token);
+			if (post == default)
+				return StatusOutcome.Fail(StatusCodes.Status404NotFound, "Record not found");
+			if (string.IsNullOrWhiteSpace(draft.Text))
+				return StatusOutcome.Fail(StatusCodes.Status422UnprocessableEntity, "Validation failed: Text can't be blank");
+
+			post.Revisions.Add(new PostRevision
+			{
+				Title = post.Title,
+				SpoilerText = post.SpoilerText,
+				ContentHtml = post.ContentHtml,
+				HasContentWarning = post.HasContentWarning,
+				EditedAt = post.EditedAt ?? post.CreationDate
+			});
+			if (post.Revisions.Count > MaxRevisions)
+				post.Revisions.RemoveRange(0, post.Revisions.Count - MaxRevisions);
+
+			var plain = draft.PlainText || post.ContentFormat == ContentFormat.Plain;
+			var rendered = plain ? await _content.PlainText(draft.Text, token) : await _content.Markdown(draft.Text, token);
+			post.Title = draft.Title == default ? post.Title : Clean(draft.Title);
+			post.SpoilerText = Clean(draft.SpoilerText);
+			post.HasContentWarning = draft.Sensitive || post.SpoilerText != default;
+			post.Text = draft.Text;
+			post.ContentHtml = rendered.Html;
+			post.Language = Clean(draft.Language) ?? post.Language;
+			post.Mentions = post.Visibility == PostVisibility.Direct
+				? post.Mentions.Concat(rendered.Mentions.Select(ToMention)).DistinctBy(m => m.ActorURI).ToList()
+				: rendered.Mentions.Select(ToMention).ToList();
+			post.Tags = rendered.Tags.ToList();
+			post.EditedAt = DateTime.UtcNow;
+			post.UpdateDate = post.EditedAt;
+			await DB.Default.SaveAsync(post, token);
+
+			if (!post.IsLocalOnly)
+			{
+				var group = string.IsNullOrEmpty(post.GroupId) ? default : await _localActors.FindById(LocalActorKind.Group, post.GroupId, token);
+				var note = post.Visibility == PostVisibility.Direct
+					? ActivityPubRenderer.DirectNote(post, author, Array.Empty<(string, string)>(), post.ContextURI)
+					: ActivityPubRenderer.Note(post, author, group, post.InReplyToURI);
+				note["to"] = new JsonArray(post.To.Select(t => (JsonNode)t).ToArray());
+				note["cc"] = new JsonArray(post.Cc.Select(c => (JsonNode)c).ToArray());
+				var update = new JsonObject
+				{
+					["@context"] = ActivityPubRenderer.Context(),
+					["id"] = author.ActivityUri($"update-{post.ID}-{new DateTimeOffset(post.EditedAt.Value).ToUnixTimeSeconds()}"),
+					["type"] = "Update",
+					["actor"] = author.Uri,
+					["to"] = note["to"]!.DeepClone(),
+					["cc"] = note["cc"]!.DeepClone(),
+					["object"] = note
+				};
+				await _outbox.Publish(author, post, update, token);
+			}
+			return new StatusOutcome(post);
+		}
+
+		public async Task<StatusOutcome> Remove(LocalActor author, string postId, CancellationToken token)
+		{
+			var post = await _dbEntities.Posts.Match(p => p.ID == postId && p.GroupUserId == author.Id && !p.IsFederatedCopy).ExecuteFirstAsync(token);
+			if (post == default || post.DeletedAt.HasValue)
+				return StatusOutcome.Fail(StatusCodes.Status404NotFound, "Record not found");
+			if (post.ReblogOfPostId != default)
+				return await Reblog(author, post.ReblogOfPostId, false, post.Visibility, token);
+
+			var audience = await _outbox.Audience(author, post, token);
+			await DB.Default.Update<PostEntity>().MatchID(post.ID)
+				.Modify(p => p.DeletedAt, DateTime.UtcNow)
+				.Modify(p => p.Text, null)
+				.Modify(p => p.ContentHtml, null)
+				.Modify(p => p.Title, null)
+				.Modify(p => p.SpoilerText, null)
+				.Modify(p => p.Media, new List<PostMedia>())
+				.Modify(p => p.Revisions, new List<PostRevision>())
+				.ExecuteAsync(token);
+			await DB.Default.DeleteAsync<TimelineEntry>(e => e.PostId == post.ID || e.ReblogOfPostId == post.ID);
+			if (!string.IsNullOrEmpty(post.AnsweringToPostId))
+				await DB.Default.Update<PostEntity>().MatchID(post.AnsweringToPostId).Modify(b => b.Inc(p => p.RepliesCount, -1)).ExecuteAsync(token);
+			if (audience.Count > 0)
+			{
+				var delete = ActivityPubRenderer.Delete(author, post.ObjectURI, $"delete-{post.ID}",
+					new JsonArray(post.To.Select(t => (JsonNode)t).ToArray()), new JsonArray(post.Cc.Select(c => (JsonNode)c).ToArray()));
+				await _delivery.Enqueue(author, audience, delete, token);
+			}
+			return new StatusOutcome(post);
+		}
+
+		public async Task<StatusOutcome> Favourite(LocalActor me, string postId, bool on, CancellationToken token)
+		{
+			var post = await Visible(me, postId, token);
+			if (post == default)
+				return StatusOutcome.Fail(StatusCodes.Status404NotFound, "Record not found");
+
+			var activityId = me.ActivityUri($"like-{post.ID}");
+			if (on)
+			{
+				try
+				{
+					await DB.Default.SaveAsync(new Favourite { AccountId = me.Id, ActorURI = me.Uri, PostId = post.ID, ActivityURI = activityId }, token);
+				}
+				catch (MongoWriteException ex) when (ex.WriteError?.Category == ServerErrorCategory.DuplicateKey)
+				{
+					return new StatusOutcome(post);
+				}
+				await DB.Default.Update<PostEntity>().MatchID(post.ID).Modify(b => b.Inc(p => p.FavouritesCount, 1)).ExecuteAsync(token);
+				post.FavouritesCount++;
+				if (!post.IsFederatedCopy)
+					await Notifications.Add(post.GroupUserId, NotificationType.Favourite, me.Id, me.Uri, post.ID, token);
+			}
+			else
+			{
+				var removed = await DB.Default.DeleteAsync<Favourite>(f => f.AccountId == me.Id && f.PostId == post.ID);
+				if (removed.DeletedCount == 0)
+					return new StatusOutcome(post);
+				await DB.Default.Update<PostEntity>().MatchID(post.ID).Modify(b => b.Inc(p => p.FavouritesCount, -1)).ExecuteAsync(token);
+				post.FavouritesCount--;
+			}
+
+			if (post.IsFederatedCopy && await AuthorInbox(post, token) is { } inbox)
+			{
+				var like = new JsonObject
+				{
+					["@context"] = ActivityPubRenderer.ActivityStreams,
+					["id"] = activityId,
+					["type"] = "Like",
+					["actor"] = me.Uri,
+					["object"] = post.ObjectURI
+				};
+				await _delivery.Enqueue(me, new[] { inbox }, on ? like : Undo(me, like, $"undo-like-{post.ID}-{DateTimeOffset.UtcNow.ToUnixTimeSeconds()}"), token);
+			}
+			return new StatusOutcome(post);
+		}
+
+		public async Task<StatusOutcome> Reblog(LocalActor me, string postId, bool on, PostVisibility visibility, CancellationToken token)
+		{
+			var original = await Visible(me, postId, token);
+			if (original?.ReblogOfPostId != default)
+				original = await Visible(me, original.ReblogOfPostId, token);
+			if (original == default)
+				return StatusOutcome.Fail(StatusCodes.Status404NotFound, "Record not found");
+			if (original.Visibility is not (PostVisibility.Public or PostVisibility.Unlisted))
+				return StatusOutcome.Fail(StatusCodes.Status422UnprocessableEntity, "Validation failed: This post can't be boosted");
+
+			var existing = await _dbEntities.Posts.Match(p => p.ReblogOfPostId == original.ID && p.AuthorAccountId == me.Id && !p.DeletedAt.HasValue).ExecuteFirstAsync(token);
+			var announceId = me.ActivityUri($"announce-{original.ID}");
+			var announce = new JsonObject
+			{
+				["@context"] = ActivityPubRenderer.ActivityStreams,
+				["id"] = announceId,
+				["type"] = "Announce",
+				["actor"] = me.Uri,
+				["published"] = ActivityPubRenderer.Timestamp(DateTime.UtcNow),
+				["to"] = new JsonArray(visibility == PostVisibility.Unlisted ? me.Followers : ActivityPubRenderer.Public),
+				["cc"] = new JsonArray(visibility == PostVisibility.Unlisted ? ActivityPubRenderer.Public : me.Followers, original.ActorURI),
+				["object"] = original.ObjectURI
+			};
+
+			if (on)
+			{
+				if (existing != default)
+					return new StatusOutcome(existing);
+				var reblog = new PostEntity
+				{
+					GroupUserId = me.Id,
+					AuthorAccountId = me.Id,
+					ReblogOfPostId = original.ID,
+					Visibility = visibility == PostVisibility.Unlisted ? PostVisibility.Unlisted : PostVisibility.Public,
+					ObjectURI = announceId,
+					ActivityURI = announceId,
+					ActorURI = me.Uri,
+					To = Strings(announce["to"]),
+					Cc = Strings(announce["cc"])
+				};
+				try
+				{
+					await DB.Default.SaveAsync(reblog, token);
+				}
+				catch (MongoWriteException ex) when (ex.WriteError?.Category == ServerErrorCategory.DuplicateKey)
+				{
+					return new StatusOutcome(await _dbEntities.Posts.Match(p => p.ObjectURI == announceId).ExecuteFirstAsync(token));
+				}
+				await DB.Default.Update<PostEntity>().MatchID(original.ID).Modify(b => b.Inc(p => p.ReblogsCount, 1)).ExecuteAsync(token);
+				if (!original.IsFederatedCopy)
+					await Notifications.Add(original.GroupUserId, NotificationType.Reblog, me.Id, me.Uri, original.ID, token);
+				await _fanout.Distribute(reblog, token);
+				await _delivery.EnqueueToFollowers(me, announce, token, await AuthorInbox(original, token) is { } inbox ? new[] { inbox } : default);
+				return new StatusOutcome(reblog);
+			}
+
+			if (existing == default)
+				return new StatusOutcome(original);
+			await DB.Default.DeleteAsync<PostEntity>(existing.ID);
+			await DB.Default.DeleteAsync<TimelineEntry>(e => e.PostId == existing.ID);
+			await DB.Default.Update<PostEntity>().MatchID(original.ID).Modify(b => b.Inc(p => p.ReblogsCount, -1)).ExecuteAsync(token);
+			await _delivery.EnqueueToFollowers(me, Undo(me, announce, $"undo-announce-{original.ID}-{DateTimeOffset.UtcNow.ToUnixTimeSeconds()}"), token,
+				await AuthorInbox(original, token) is { } authorInbox ? new[] { authorInbox } : default);
+			return new StatusOutcome(original);
+		}
+
+		sealed record Recipient(string Uri, string Handle, string LocalId, string ForeignId, string Inbox);
+
+		sealed record ConversationResult(DmGroup Group, IReadOnlyList<Recipient> Recipients, int Status = StatusCodes.Status200OK, string Error = default)
+		{
+			public bool Ok => Error == default;
+		}
+
+		async Task<ConversationResult> Conversation(LocalActor author, StatusDraft draft, IReadOnlyList<ResolvedMention> mentioned, CancellationToken token)
+		{
+			DmGroup dmGroup = default;
+			if (!string.IsNullOrEmpty(draft.ConversationId))
+			{
+				dmGroup = await _dbEntities.DmGroups.MatchID(draft.ConversationId).ExecuteFirstAsync(token);
+				if (dmGroup == default || !dmGroup.Members.Any(m => !m.IsForeign && m.AvatarId == author.Id))
+					return new(default, default, StatusCodes.Status404NotFound, "Conversation not found");
+			}
+			else
+			{
+				var members = new List<GroupMember> { new() { AvatarId = author.Id } };
+				foreach (var handle in draft.Recipients.Distinct(StringComparer.OrdinalIgnoreCase))
+				{
+					var member = await ResolveRecipient(handle, token);
+					if (member == default)
+						return new(default, default, StatusCodes.Status404NotFound, $"Recipient '{handle}' not found");
+					if (members.All(m => m.AvatarId != member.AvatarId))
+						members.Add(member);
+				}
+				foreach (var mention in mentioned.Where(m => m.AccountId != author.Id))
+				{
+					var member = mention.IsLocal ? new GroupMember { AvatarId = mention.AccountId } : new GroupMember { AvatarId = mention.ActorUri, IsForeign = true };
+					if (members.All(m => m.AvatarId != member.AvatarId))
+						members.Add(member);
+				}
+				if (members.Count < 2)
+					return new(default, default, StatusCodes.Status422UnprocessableEntity, "Validation failed: A direct message needs at least one recipient");
+
+				var key = DmGroup.KeyOf(members);
+				dmGroup = await _dbEntities.DmGroups.Match(g => g.ParticipantsKey == key && !g.DeletionAt.HasValue).ExecuteFirstAsync(token);
+				if (dmGroup == default)
+				{
+					dmGroup = new DmGroup { Members = members, ParticipantsKey = key };
+					dmGroup.ID = (string)dmGroup.GenerateNewID();
+					dmGroup.ConversationURI = author.ConversationUri(dmGroup.ID);
+					await DB.Default.SaveAsync(dmGroup, token);
+				}
+			}
+
+			var recipients = new List<Recipient>();
+			foreach (var member in dmGroup.Members.Where(m => !(m.AvatarId == author.Id && !m.IsForeign)))
+			{
+				if (member.IsForeign)
+				{
+					var foreign = await _dbEntities.ForeignAvatars.Match(a => a.ActorURI == member.AvatarId).ExecuteFirstAsync(token);
+					if (foreign != default)
+						recipients.Add(new Recipient(foreign.ActorURI, $"{foreign.UserName}@{foreign.Domain}", default, foreign.ID, foreign.InboxURL));
+				}
+				else if (await _localActors.FindById(LocalActorKind.Person, member.AvatarId, token) is { } local)
+					recipients.Add(new Recipient(local.Uri, local.Handle, local.Id, default, default));
+			}
+			return new(dmGroup, recipients);
+		}
+
+		async Task<GroupMember> ResolveRecipient(string recipient, CancellationToken token)
+		{
+			var handle = recipient.Trim().TrimStart('@');
+			if (!handle.Contains('@') || handle.EndsWith("@" + new Uri(_localActors.BaseAddress).Authority, StringComparison.OrdinalIgnoreCase))
+			{
+				var local = await _localActors.FindByUserName(handle.Split('@')[0], token);
+				return local is { Kind: LocalActorKind.Person } ? new GroupMember { AvatarId = local.Id } : default;
+			}
+			var actorUri = await _remoteActors.ResolveHandle(handle, token);
+			var foreign = actorUri == default ? default : await _remoteActors.GetActor(actorUri, refresh: false, token);
+			return foreign == default ? default : new GroupMember { AvatarId = foreign.ActorURI, IsForeign = true };
+		}
+
+		async Task<PostEntity> Parent(string reference, CancellationToken token)
+		{
+			if (string.IsNullOrEmpty(reference))
+				return default;
+			return IsRemoteUri(reference)
+				? await _dbEntities.Posts.Match(p => p.ObjectURI == reference && !p.DeletedAt.HasValue).ExecuteFirstAsync(token)
+				: await _dbEntities.Posts.Match(p => p.ID == reference && !p.DeletedAt.HasValue).ExecuteFirstAsync(token);
+		}
+
+		async Task<PostEntity> Own(LocalActor author, string postId, CancellationToken token) =>
+			await _dbEntities.Posts.Match(p => p.ID == postId && p.GroupUserId == author.Id && !p.IsFederatedCopy && !p.DeletedAt.HasValue && p.ReblogOfPostId == null)
+				.ExecuteFirstAsync(token);
+
+		async Task<PostEntity> Visible(LocalActor me, string postId, CancellationToken token)
+		{
+			var post = string.IsNullOrEmpty(postId) ? default : await _dbEntities.Posts.Match(p => p.ID == postId && !p.DeletedAt.HasValue).ExecuteFirstAsync(token);
+			return post != default && await VisibilityPolicy.CanSee(post, me.Id, token) ? post : default;
+		}
+
+		async Task<string> AuthorInbox(PostEntity post, CancellationToken token)
+		{
+			if (!post.IsFederatedCopy || string.IsNullOrEmpty(post.AuthorAccountId))
+				return default;
+			return (await _dbEntities.ForeignAvatars.MatchID(post.AuthorAccountId).ExecuteFirstAsync(token))?.InboxURL;
+		}
+
+		static JsonObject Undo(LocalActor actor, JsonObject inner, string activityId) => new()
+		{
+			["@context"] = ActivityPubRenderer.ActivityStreams,
+			["id"] = actor.ActivityUri(activityId),
+			["type"] = "Undo",
+			["actor"] = actor.Uri,
+			["object"] = inner.DeepClone()
+		};
+
+		static PostMention ToMention(ResolvedMention mention) => new()
+		{
+			ActorURI = mention.ActorUri,
+			Handle = "@" + mention.Handle,
+			IsLocal = mention.IsLocal,
+			AccountId = mention.AccountId
+		};
+
+		static bool IsRemoteUri(string reference) =>
+			reference != default && (reference.StartsWith("https://", StringComparison.OrdinalIgnoreCase) || reference.StartsWith("http://", StringComparison.OrdinalIgnoreCase));
+
+		static string Clean(string value) => string.IsNullOrWhiteSpace(value) ? default : value.Trim();
+
+		static List<string> Strings(JsonNode node) =>
+			node is JsonArray array ? array.Select(n => n?.GetValue<string>()).Where(s => s != default).ToList() : new List<string>();
+	}
+}

PrivaPub/Federation/Actors/LocalActorService.cs

@@ -29,6 +29,9 @@ namespace PrivaPub.Federation.Actors
 		public bool Discoverable { get; init; } = true;
 		public bool ManuallyApprovesFollowers { get; init; }
 		public bool IsFederated { get; init; } = true;
+		public bool IsBot { get; init; }
+		public bool Indexable { get; init; }
+		public AvatarSettings Settings { get; init; } = new();
 		public DateTime Published { get; init; }
 		public string BaseAddress { get; init; }
 		public IReadOnlyDictionary<string, string> Fields { get; init; } = new Dictionary<string, string>();
@@ -195,6 +198,11 @@ namespace PrivaPub.Federation.Actors
 			PublicKeyPem = avatar.PublicKey,
 			Published = avatar.CreatedAt,
 			Fields = avatar.Fields ?? new Dictionary<string, string>(),
+			ManuallyApprovesFollowers = avatar.Settings?.IsLocked == true,
+			Discoverable = avatar.Settings?.IsDiscoverable != false,
+			IsBot = avatar.Settings?.IsBot == true,
+			Indexable = avatar.Settings?.IsIndexable == true,
+			Settings = avatar.Settings ?? new AvatarSettings(),
 			BaseAddress = BaseAddress
 		};
 

PrivaPub/Federation/Controllers/PeasantsController.cs

@@ -80,6 +80,12 @@ namespace PrivaPub.Federation.Controllers
 					items.Add(ActivityPubRenderer.Announce(local, post.ObjectURI, $"announce-{post.ID}"));
 					continue;
 				}
+				if (post.ReblogOfPostId != default)
+				{
+					if (await AnnounceFor(post, token) is { } announce)
+						items.Add(announce);
+					continue;
+				}
 				items.Add(await CreateFor(post, local, token));
 			}
 
@@ -124,6 +130,14 @@ namespace PrivaPub.Federation.Controllers
 		[HttpGet, Route("{actor}/grunts/{activityId}")]
 		public async Task<IActionResult> Grunt(string actor, string activityId, CancellationToken token)
 		{
+			if (activityId.StartsWith("announce-", StringComparison.Ordinal))
+			{
+				var booster = await _localActors.FindByUserName(actor, token);
+				var uri = booster?.ActivityUri(activityId);
+				var reblog = uri == default ? default : await _dbEntities.Posts.Match(p => p.ObjectURI == uri && !p.DeletedAt.HasValue).ExecuteFirstAsync(token);
+				var rendered = reblog == default ? default : await AnnounceFor(reblog, token);
+				return rendered == default ? NotFound() : Activity(rendered);
+			}
 			if (!activityId.StartsWith("create-", StringComparison.Ordinal))
 				return NotFound();
 			var (local, post) = await PublicPost(actor, activityId["create-".Length..], token);
@@ -153,7 +167,7 @@ namespace PrivaPub.Federation.Controllers
 			if (local is not { IsFederated: true, Kind: LocalActorKind.Person })
 				return default;
 			var post = await _dbEntities.Posts
-				.Match(p => p.ID == postId && p.GroupUserId == local.Id && !p.IsFederatedCopy)
+				.Match(p => p.ID == postId && p.GroupUserId == local.Id && !p.IsFederatedCopy && p.ReblogOfPostId == null)
 				.Match(VisibilityPolicy.IsPublic)
 				.ExecuteFirstAsync(token);
 			return (local, post);
@@ -181,6 +195,24 @@ namespace PrivaPub.Federation.Controllers
 			return new ContentResult { Content = tombstone.ToJsonString(), ContentType = ActivityContentType, StatusCode = StatusCodes.Status410Gone };
 		}
 
+		async Task<JsonObject> AnnounceFor(PostEntity reblog, CancellationToken token)
+		{
+			var original = await _dbEntities.Posts.MatchID(reblog.ReblogOfPostId).ExecuteFirstAsync(token);
+			if (original == default || original.DeletedAt.HasValue)
+				return default;
+			return new JsonObject
+			{
+				["@context"] = ActivityPubRenderer.ActivityStreams,
+				["id"] = reblog.ObjectURI,
+				["type"] = "Announce",
+				["actor"] = reblog.ActorURI,
+				["published"] = ActivityPubRenderer.Timestamp(reblog.CreationDate),
+				["to"] = new JsonArray(reblog.To.Select(t => (JsonNode)t).ToArray()),
+				["cc"] = new JsonArray(reblog.Cc.Select(c => (JsonNode)c).ToArray()),
+				["object"] = original.ObjectURI
+			};
+		}
+
 		async Task<JsonObject> CreateFor(PostEntity post, LocalActor author, CancellationToken token)
 		{
 			var group = string.IsNullOrEmpty(post.GroupId) ? default : await _localActors.FindById(LocalActorKind.Group, post.GroupId, token);

PrivaPub/Federation/Controllers/WellKnownController.cs

@@ -85,7 +85,7 @@ namespace PrivaPub.Federation.Controllers
 		public async Task<IActionResult> NodeInfo(string version, CancellationToken token)
 		{
 			var users = await DB.Default.CountAsync<Avatar>(a => !a.DeletionAt.HasValue, token);
-			var posts = await DB.Default.CountAsync<PostEntity>(f => f.Where(p => !p.IsFederatedCopy) & f.Where(VisibilityPolicy.IsPublic), token);
+			var posts = await DB.Default.CountAsync<PostEntity>(f => f.Where(p => !p.IsFederatedCopy && p.ReblogOfPostId == null) & f.Where(VisibilityPolicy.IsPublic), token);
 			var software = new JsonObject { ["name"] = "privapub", ["version"] = BuildInfo.Ref };
 			if (version == "2.1")
 			{

PrivaPub/Federation/Objects/NoteParser.cs

@@ -166,7 +166,7 @@ namespace PrivaPub.Federation.Objects
 				: default;
 
 		static int? Int(JsonNode node) =>
-			node is JsonValue value && value.TryGetValue<int>(out var number) && number is > 0 and < 100_000 ? number : default;
+			node is JsonValue value && value.TryGetValue<int>(out var number) && number is > 0 and < 100_000 ? number : (int?)null;
 
 		static string Plain(string value, int max)
 		{

PrivaPub/Federation/Rendering/ActivityPubRenderer.cs

@@ -65,6 +65,7 @@ namespace PrivaPub.Federation.Rendering
 				{
 					LocalActorKind.Group => "Group",
 					LocalActorKind.Application => "Application",
+					_ when actor.IsBot => "Service",
 					_ => "Person"
 				},
 				["preferredUsername"] = actor.UserName,
@@ -78,7 +79,7 @@ namespace PrivaPub.Federation.Rendering
 				["published"] = Day(actor.Published),
 				["manuallyApprovesFollowers"] = actor.ManuallyApprovesFollowers,
 				["discoverable"] = actor.Discoverable,
-				["indexable"] = false,
+				["indexable"] = actor.Indexable,
 				["webfinger"] = actor.Handle,
 				["endpoints"] = new JsonObject { ["sharedInbox"] = actor.SharedInbox },
 				["publicKey"] = new JsonObject
@@ -190,7 +191,7 @@ namespace PrivaPub.Federation.Rendering
 			return "@" + (handle.Contains('@') ? handle : $"{handle}@{new Uri(mention.ActorURI).Authority}");
 		}
 
-		static string FieldValue(string value)
+		public static string FieldValue(string value)
 		{
 			var encoded = WebUtility.HtmlEncode(value ?? string.Empty);
 			return Uri.TryCreate(value, UriKind.Absolute, out var link) && link.Scheme is "https" or "http"

PrivaPub/Infrastructure/Data/Indexes.cs

@@ -82,6 +82,11 @@ namespace PrivaPub.Infrastructure.Data
 				.Option(o => o.Unique = true)
 				.CreateAsync(token);
 			await Plain<Favourite>(token, f => f.ActivityURI);
+			await DB.Default.Index<Marker>()
+				.Key(m => m.AvatarId, KeyType.Ascending)
+				.Key(m => m.Timeline, KeyType.Ascending)
+				.Option(o => o.Unique = true)
+				.CreateAsync(token);
 			await Unique<DomainBlock>(b => b.Domain, Builders<DomainBlock>.Filter.Type(b => b.Domain, BsonType.String), token);
 			await Unique<RemoteInstance>(i => i.Host, Builders<RemoteInstance>.Filter.Type(i => i.Host, BsonType.String), token);
 		}

PrivaPub/Middleware/SocialPubConfigurations.cs

@@ -1,6 +1,8 @@
 using Microsoft.AspNetCore.Authentication.JwtBearer;
 using Microsoft.AspNetCore.ResponseCompression;
 
+using OpenIddict.Validation.AspNetCore;
+
 using PrivaPub.ClientModels;
 using PrivaPub.Extensions;
 using PrivaPub.Models;
@@ -18,6 +20,7 @@ using PrivaPub.Federation.Moderation;
 using PrivaPub.Federation.Inbox.Handlers;
 using PrivaPub.Domain.Content;
 using PrivaPub.Domain.Social;
+using PrivaPub.Domain.Statuses;
 using PrivaPub.Domain.Timelines;
 using PrivaPub.Infrastructure.Http;
 using PrivaPub.Infrastructure.Jobs;
@@ -27,6 +30,8 @@ namespace PrivaPub.Middleware
 {
 	public static class PrivaPubConfigurations
 	{
+		const string SchemeSelector = "PrivaPub";
+
 		public static IServiceCollection PrivaPubAppSettingsConfiguration(this IServiceCollection service, IConfiguration configuration)
 		{
 			return service
@@ -89,10 +94,14 @@ namespace PrivaPub.Middleware
 				})
 				.AddAuthentication(options =>
 				{
-					options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
+					options.DefaultAuthenticateScheme = SchemeSelector;
-					options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
+					options.DefaultChallengeScheme = SchemeSelector;
-					options.DefaultScheme = JwtBearerDefaults.AuthenticationScheme;
+					options.DefaultScheme = SchemeSelector;
 				})
+				.AddPolicyScheme(SchemeSelector, SchemeSelector, options => options.ForwardDefaultSelector = context =>
+					context.Request.Path.StartsWithSegments("/api")
+						? OpenIddictValidationAspNetCoreDefaults.AuthenticationScheme
+						: JwtBearerDefaults.AuthenticationScheme)
 				.AddPrivaPubAuth(configuration)
 				.Services
 				.AddSingleton<AuthTokenManager>()
@@ -128,6 +137,7 @@ namespace PrivaPub.Middleware
 				.AddTransient<IPrivateAvatarUsersService, PrivateAvatarUsersService>()
 				.AddTransient<IGroupUsersService, GroupUsersService>()
 				.AddTransient<IPostsService, PostsService>()
+				.AddTransient<IStatusService, StatusService>()
 				.AddTransient<IFollowService, FollowService>()
 				.AddTransient<ITimelineService, TimelineService>()
 				.AddSingleton<AppConfigurationService>()
@@ -179,7 +189,7 @@ namespace PrivaPub.Middleware
 					configure.AllowAnyMethod()
 						.AllowAnyHeader()
 						.AllowAnyOrigin()
-						.AllowAnyMethod()
+						.WithExposedHeaders("Link", "X-RateLimit-Remaining", "X-RateLimit-Reset")
 						.DisallowCredentials();
 				});
 			});

PrivaPub/Models/Post/ContentFormat.cs

@@ -3,6 +3,7 @@ namespace PrivaPub.Models.Post
 	public enum ContentFormat
 	{
 		Markdown,
-		Html
+		Html,
+		Plain
 	}
 }

PrivaPub/Models/Social/Marker.cs

@@ -0,0 +1,13 @@
+using MongoDB.Entities;
+
+namespace PrivaPub.Models.Social
+{
+	public class Marker : Entity
+	{
+		public string AvatarId { get; set; }
+		public string Timeline { get; set; }
+		public string LastReadId { get; set; }
+		public int Version { get; set; }
+		public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
+	}
+}

PrivaPub/Models/User/Avatar.cs

@@ -93,6 +93,15 @@ namespace PrivaPub.Models.User
 		public bool ThemeIsDarkMode { get; set; } = false;
 		public bool ThemeIsDarkGray { get; set; } = false;
 		public bool ThemeIsLightGray { get; set; } = true;
+
+		public bool IsLocked { get; set; }
+		public bool IsBot { get; set; }
+		public bool IsDiscoverable { get; set; } = true;
+		public bool IsIndexable { get; set; }
+		public bool HideCollections { get; set; } = true;
+		public string DefaultVisibility { get; set; } = "public";
+		public bool DefaultSensitive { get; set; }
+		public string DefaultLanguage { get; set; }
 	}
 
 	public enum AvatarServer

PrivaPub/PrivaPub.csproj

@@ -12,6 +12,8 @@
     <PackageReference Include="Markdig" Version="1.4.0" />
     <PackageReference Include="Microsoft.AspNetCore.Authentication.JwtBearer" Version="10.0.9" />
     <PackageReference Include="MongoDB.Entities" Version="25.1.0" />
+    <PackageReference Include="OpenIddict.AspNetCore" Version="7.7.1" />
+    <PackageReference Include="OpenIddict.MongoDb" Version="7.7.1" />
     <PackageReference Include="PasswordGenerator" Version="3.0.0" />
     <PackageReference Include="Serilog.AspNetCore" Version="10.0.0" />
     <PackageReference Include="Serilog.Sinks.MongoDB" Version="7.3.0" />

PrivaPub/Program.cs

@@ -11,6 +11,7 @@ using Serilog;
 
 using PrivaPub.Data;
 using PrivaPub.Extensions;
+using PrivaPub.Api.Mastodon.Auth;
 using PrivaPub.Infrastructure;
 using PrivaPub.Infrastructure.Cli;
 using PrivaPub.Infrastructure.Data;
@@ -54,6 +55,9 @@ try
 			.PrivaPubFederationConfiguration(builder.Configuration)
 			.PrivaPubCORSConfiguration()
 			.PrivaPubRateLimiting()
+			.PrivaPubOAuth(builder.Environment)
+			.AddScoped<PrivaPub.Api.Mastodon.Mappers.MastodonMapper>()
+			.AddScoped<PrivaPub.Api.Mastodon.Mappers.AccountSearch>()
 			.PrivaPubMiddlewareConfiguration();
 	}
 	catch (Exception ex)

PrivaPub/Services/JwtEvents.cs

@@ -19,7 +19,7 @@ namespace PrivaPub.Services
 			try
 			{
 				var localizer = context.HttpContext.RequestServices.GetRequiredService<IStringLocalizer<GenericRes>>();
-				var webResult = new WebResult().Invalidate(localizer["Unauthorized: {0}", context.Exception], StatusCodes.Status401Unauthorized);
+				var webResult = new WebResult().Invalidate(localizer["Unauthorized."], StatusCodes.Status401Unauthorized);
 				context.Response.ContentType = contentType;
 				await context.Response.BodyWriter.WriteAsync(Encoding.UTF8.GetBytes(JsonSerializer.Serialize(webResult)));
 			}
@@ -35,7 +35,7 @@ namespace PrivaPub.Services
 			try
 			{
 				var localizer = context.HttpContext.RequestServices.GetRequiredService<IStringLocalizer<GenericRes>>();
-				var webResult = new WebResult().Invalidate(localizer["Forbidden: {0}", context.Result.None ? "N/A" : context.Result.Failure?.Message ?? "N/A"], StatusCodes.Status403Forbidden);
+				var webResult = new WebResult().Invalidate(localizer["Forbidden."], StatusCodes.Status403Forbidden);
 				context.Response.ContentType = contentType;
 				await context.Response.BodyWriter.WriteAsync(Encoding.UTF8.GetBytes(JsonSerializer.Serialize(webResult)));
 			}

PrivaPub/Services/PostsService.cs

@@ -14,7 +14,7 @@ using PrivaPub.StaticServices;
 using System.Text.Json.Nodes;
 
 using PostEntity = PrivaPub.Models.Post.Post;
-using PrivaPub.Domain.Content;
+using PrivaPub.Domain.Statuses;
 using PrivaPub.Domain.Timelines;
 using PrivaPub.Federation.Actors;
 using PrivaPub.Federation.Rendering;
@@ -38,225 +38,62 @@ namespace PrivaPub.Services
 
 		readonly DbEntities _dbEntities;
 		readonly ILocalActorService _localActors;
-		readonly IRemoteActorService _remoteActors;
+		readonly IStatusService _statuses;
-		readonly IDeliveryService _delivery;
-		readonly IContentRenderer _content;
-		readonly IOutboxPublisher _outbox;
-		readonly IFanout _fanout;
 		readonly IStringLocalizer<GenericRes> _localizer;
 		readonly ILogger<PostsService> _logger;
 
 		public PostsService(DbEntities dbEntities,
 			ILocalActorService localActors,
-			IRemoteActorService remoteActors,
+			IStatusService statuses,
-			IDeliveryService delivery,
-			IContentRenderer content,
-			IOutboxPublisher outbox,
-			IFanout fanout,
 			IStringLocalizer<GenericRes> localizer,
 			ILogger<PostsService> logger)
 		{
 			_dbEntities = dbEntities;
 			_localActors = localActors;
-			_remoteActors = remoteActors;
+			_statuses = statuses;
-			_delivery = delivery;
-			_content = content;
-			_outbox = outbox;
-			_fanout = fanout;
 			_localizer = localizer;
 			_logger = logger;
 		}
 
 		public async Task<WebResult> InsertPost(string rootUserId, InsertPostForm form, CancellationToken token)
-		{
-			var result = new WebResult();
-			try
 		{
 			var author = await OwnedAvatar(rootUserId, form.AvatarId, token);
 			if (author == default)
-					return result.Invalidate(_localizer["Avatar not found."], StatusCodes.Status404NotFound);
+				return new WebResult().Invalidate(_localizer["Avatar not found."], StatusCodes.Status404NotFound);
-
+			return await Answer(() => _statuses.Publish(author, new StatusDraft
-				LocalActor group = default;
-				var isLocalOnly = false;
-				if (!string.IsNullOrEmpty(form.GroupId))
 			{
-					var groupEntity = await _dbEntities.Groups.MatchID(form.GroupId).ExecuteFirstAsync(token);
-					if (groupEntity == default || groupEntity.DeletionAt.HasValue
-						|| !groupEntity.Members.Any(m => !m.IsForeign && m.AvatarId == form.AvatarId))
-						return result.Invalidate(_localizer["Group not found."], StatusCodes.Status404NotFound);
-					group = _localActors.FromGroup(groupEntity);
-					isLocalOnly = !group.IsFederated;
-				}
-
-				var parent = await Parent(form.AnsweringToPostId, token);
-				var rendered = await _content.Markdown(form.Text, token);
-				var post = new PostEntity
-				{
-					GroupUserId = author.Id,
-					AuthorAccountId = author.Id,
-					GroupId = group?.Id,
-					Visibility = isLocalOnly ? PostVisibility.Circle : LocalVisibility(form.Visibility),
-					Title = form.Title,
-					SpoilerText = string.IsNullOrWhiteSpace(form.SpoilerText) ? default : form.SpoilerText.Trim(),
 				Text = form.Text,
-					ContentHtml = rendered.Html,
+				Title = form.Title,
-					ContentFormat = ContentFormat.Markdown,
+				SpoilerText = form.SpoilerText,
-					Mentions = rendered.Mentions.Select(ToMention).ToList(),
+				Sensitive = form.HasContentWarning,
-					Tags = rendered.Tags.ToList(),
+				Visibility = LocalVisibility(form.Visibility),
-					HasContentWarning = form.HasContentWarning || !string.IsNullOrWhiteSpace(form.SpoilerText),
+				InReplyTo = form.AnsweringToPostId,
-					AnsweringToPostId = parent?.ID,
+				GroupId = form.GroupId
-					InReplyToURI = parent?.ObjectURI ?? RemoteUri(form.AnsweringToPostId),
+			}, token), nameof(InsertPost));
-					InReplyToAccountId = parent?.AuthorAccountId ?? parent?.GroupUserId,
-					IsLocalOnly = isLocalOnly,
-					ActorURI = author.Uri
-				};
-				post.ID = (string)post.GenerateNewID();
-				post.ObjectURI = author.PostUri(post.ID);
-				post.Url = author.PostHtmlUrl(post.ID);
-
-				if (isLocalOnly)
-				{
-					await DB.Default.SaveAsync(post, token);
-					await _fanout.Distribute(post, token);
-					result.Data = ToView(post);
-					return result;
-				}
-
-				var note = ActivityPubRenderer.Note(post, author, group, post.InReplyToURI);
-				var create = ActivityPubRenderer.Create(author, note, $"create-{post.ID}");
-				post.ActivityURI = create["id"]!.GetValue<string>();
-				post.To = Strings(note["to"]);
-				post.Cc = Strings(note["cc"]);
-				await DB.Default.SaveAsync(post, token);
-				if (parent != default)
-					await DB.Default.Update<PostEntity>().MatchID(parent.ID).Modify(b => b.Inc(p => p.RepliesCount, 1)).ExecuteAsync(token);
-
-				await _fanout.Distribute(post, token);
-				await _outbox.Publish(author, post, create, token);
-				if (group is { IsFederated: true } && post.Visibility is PostVisibility.Public or PostVisibility.Unlisted)
-					await _delivery.EnqueueToFollowers(group, ActivityPubRenderer.Announce(group, post.ObjectURI, $"announce-{post.ID}"), token);
-
-				result.Data = ToView(post);
-				return result;
-			}
-			catch (Exception ex)
-			{
-				_logger.LogError(ex, $"{nameof(PostsService)}.{nameof(InsertPost)}");
-				return result.Invalidate(_localizer["Something went wrong."], exception: ex);
-			}
 		}
 
 		public async Task<WebResult> DeletePost(string rootUserId, DeletePostForm form, CancellationToken token)
-		{
-			var result = new WebResult();
-			try
 		{
 			var author = await OwnedAvatar(rootUserId, form.AvatarId, token);
 			if (author == default)
-					return result.Invalidate(_localizer["Avatar not found."], StatusCodes.Status404NotFound);
+				return new WebResult().Invalidate(_localizer["Avatar not found."], StatusCodes.Status404NotFound);
-
+			var result = await Answer(() => _statuses.Remove(author, form.PostId, token), nameof(DeletePost));
-				var post = await _dbEntities.Posts
+			result.Data = default;
-					.Match(p => p.ID == form.PostId && p.GroupUserId == author.Id && !p.IsFederatedCopy)
-					.ExecuteFirstAsync(token);
-				if (post == default)
-					return result.Invalidate(_localizer["Post not found."], StatusCodes.Status404NotFound);
-
-				if (post.DeletedAt.HasValue)
 			return result;
-				var audience = await _outbox.Audience(author, post, token);
-				await DB.Default.Update<PostEntity>().MatchID(post.ID)
-					.Modify(p => p.DeletedAt, DateTime.UtcNow)
-					.Modify(p => p.Text, null)
-					.Modify(p => p.ContentHtml, null)
-					.Modify(p => p.Title, null)
-					.Modify(p => p.SpoilerText, null)
-					.Modify(p => p.Media, new List<PostMedia>())
-					.Modify(p => p.Revisions, new List<PostRevision>())
-					.ExecuteAsync(token);
-				await DB.Default.DeleteAsync<TimelineEntry>(e => e.PostId == post.ID);
-				if (!string.IsNullOrEmpty(post.AnsweringToPostId))
-					await DB.Default.Update<PostEntity>().MatchID(post.AnsweringToPostId).Modify(b => b.Inc(p => p.RepliesCount, -1)).ExecuteAsync(token);
-
-				if (audience.Count > 0)
-				{
-					var delete = ActivityPubRenderer.Delete(author, post.ObjectURI, $"delete-{post.ID}",
-						new JsonArray(post.To.Select(t => (JsonNode)t).ToArray()), new JsonArray(post.Cc.Select(c => (JsonNode)c).ToArray()));
-					await _delivery.Enqueue(author, audience, delete, token);
-				}
-				return result;
-			}
-			catch (Exception ex)
-			{
-				_logger.LogError(ex, $"{nameof(PostsService)}.{nameof(DeletePost)}");
-				return result.Invalidate(_localizer["Something went wrong."], exception: ex);
-			}
 		}
 
 		public async Task<WebResult> UpdatePost(string rootUserId, UpdatePostForm form, CancellationToken token)
-		{
-			var result = new WebResult();
-			try
 		{
 			var author = await OwnedAvatar(rootUserId, form.AvatarId, token);
 			if (author == default)
-					return result.Invalidate(_localizer["Avatar not found."], StatusCodes.Status404NotFound);
+				return new WebResult().Invalidate(_localizer["Avatar not found."], StatusCodes.Status404NotFound);
-				var post = await _dbEntities.Posts
+			return await Answer(() => _statuses.Edit(author, form.PostId, new StatusDraft
-					.Match(p => p.ID == form.PostId && p.GroupUserId == author.Id && !p.IsFederatedCopy && !p.DeletedAt.HasValue)
-					.ExecuteFirstAsync(token);
-				if (post == default)
-					return result.Invalidate(_localizer["Post not found."], StatusCodes.Status404NotFound);
-
-				post.Revisions.Add(new PostRevision
 			{
-					Title = post.Title,
+				Text = form.Text,
-					SpoilerText = post.SpoilerText,
+				Title = form.Title,
-					ContentHtml = post.ContentHtml,
+				SpoilerText = form.SpoilerText,
-					HasContentWarning = post.HasContentWarning,
+				Sensitive = form.HasContentWarning
-					EditedAt = post.EditedAt ?? post.CreationDate
+			}, token), nameof(UpdatePost));
-				});
-				var rendered = await _content.Markdown(form.Text, token);
-				post.Title = form.Title;
-				post.SpoilerText = string.IsNullOrWhiteSpace(form.SpoilerText) ? default : form.SpoilerText.Trim();
-				post.HasContentWarning = form.HasContentWarning || post.SpoilerText != default;
-				post.Text = form.Text;
-				post.ContentHtml = rendered.Html;
-				post.Mentions = post.Visibility == PostVisibility.Direct
-					? post.Mentions.Concat(rendered.Mentions.Select(ToMention)).DistinctBy(m => m.ActorURI).ToList()
-					: rendered.Mentions.Select(ToMention).ToList();
-				post.Tags = rendered.Tags.ToList();
-				post.EditedAt = DateTime.UtcNow;
-				post.UpdateDate = post.EditedAt;
-				await DB.Default.SaveAsync(post, token);
-
-				if (!post.IsLocalOnly)
-				{
-					var group = string.IsNullOrEmpty(post.GroupId) ? default : await _localActors.FindById(LocalActorKind.Group, post.GroupId, token);
-					var note = post.Visibility == PostVisibility.Direct
-						? ActivityPubRenderer.DirectNote(post, author, Array.Empty<(string, string)>(), post.ContextURI)
-						: ActivityPubRenderer.Note(post, author, group, post.InReplyToURI);
-					note["to"] = new JsonArray(post.To.Select(t => (JsonNode)t).ToArray());
-					note["cc"] = new JsonArray(post.Cc.Select(c => (JsonNode)c).ToArray());
-					var update = new JsonObject
-					{
-						["@context"] = ActivityPubRenderer.Context(),
-						["id"] = author.ActivityUri($"update-{post.ID}-{new DateTimeOffset(post.EditedAt.Value).ToUnixTimeSeconds()}"),
-						["type"] = "Update",
-						["actor"] = author.Uri,
-						["to"] = note["to"]!.DeepClone(),
-						["cc"] = note["cc"]!.DeepClone(),
-						["object"] = note
-					};
-					await _outbox.Publish(author, post, update, token);
-				}
-
-				result.Data = ToView(post);
-				return result;
-			}
-			catch (Exception ex)
-			{
-				_logger.LogError(ex, $"{nameof(PostsService)}.{nameof(UpdatePost)}");
-				return result.Invalidate(_localizer["Something went wrong."], exception: ex);
-			}
 		}
 
 		public async Task<WebResult> GetPosts(string rootUserId, string avatarId, string groupId, CancellationToken token)
@@ -293,98 +130,20 @@ namespace PrivaPub.Services
 		}
 
 		public async Task<WebResult> InsertDm(string rootUserId, InsertDmForm form, CancellationToken token)
-		{
-			var result = new WebResult();
-			try
 		{
 			var author = await OwnedAvatar(rootUserId, form.AvatarId, token);
 			if (author == default)
-					return result.Invalidate(_localizer["Avatar not found."], StatusCodes.Status404NotFound);
+				return new WebResult().Invalidate(_localizer["Avatar not found."], StatusCodes.Status404NotFound);
-
+			if (string.IsNullOrEmpty(form.DmGroupId) && form.Recipients.Count == 0)
-				DmGroup dmGroup;
+				return new WebResult().Invalidate(_localizer["At least one recipient is required."]);
-				if (!string.IsNullOrEmpty(form.DmGroupId))
+			return await Answer(() => _statuses.Publish(author, new StatusDraft
 			{
-					dmGroup = await _dbEntities.DmGroups.MatchID(form.DmGroupId).ExecuteFirstAsync(token);
-					if (dmGroup == default || !dmGroup.Members.Any(m => !m.IsForeign && m.AvatarId == author.Id))
-						return result.Invalidate(_localizer["Conversation not found."], StatusCodes.Status404NotFound);
-				}
-				else
-				{
-					if (form.Recipients.Count == 0)
-						return result.Invalidate(_localizer["At least one recipient is required."]);
-					var members = new List<GroupMember> { new() { AvatarId = author.Id } };
-					foreach (var recipient in form.Recipients.Distinct(StringComparer.OrdinalIgnoreCase))
-					{
-						var member = await ResolveRecipient(recipient, token);
-						if (member == default)
-							return result.Invalidate(_localizer["Recipient '{0}' not found.", recipient], StatusCodes.Status404NotFound);
-						if (members.All(m => m.AvatarId != member.AvatarId))
-							members.Add(member);
-					}
-					var key = DmGroup.KeyOf(members);
-					dmGroup = await _dbEntities.DmGroups.Match(g => g.ParticipantsKey == key && !g.DeletionAt.HasValue).ExecuteFirstAsync(token);
-					if (dmGroup == default)
-					{
-						dmGroup = new DmGroup { Members = members, ParticipantsKey = key };
-						dmGroup.ID = (string)dmGroup.GenerateNewID();
-						dmGroup.ConversationURI = author.ConversationUri(dmGroup.ID);
-						await DB.Default.SaveAsync(dmGroup, token);
-					}
-				}
-
-				var dm = new PostEntity
-				{
-					GroupUserId = author.Id,
-					AuthorAccountId = author.Id,
-					ConversationId = dmGroup.ID,
-					Visibility = PostVisibility.Direct,
-					ContextURI = dmGroup.ConversationURI,
 				Text = form.Text,
-					ContentHtml = (await _content.Markdown(form.Text, token)).Html,
+				Sensitive = form.HasContentWarning,
-					ContentFormat = ContentFormat.Markdown,
+				Visibility = PostVisibility.Direct,
-					HasContentWarning = form.HasContentWarning,
+				ConversationId = form.DmGroupId,
-					ActorURI = author.Uri
+				Recipients = form.Recipients
-				};
+			}, token), nameof(InsertDm));
-				dm.ID = (string)dm.GenerateNewID();
-				dm.ObjectURI = author.PostUri(dm.ID);
-				dm.Url = author.PostHtmlUrl(dm.ID);
-
-				var remote = new List<(string Uri, string Handle)>();
-				var inboxes = new List<string>();
-				foreach (var member in dmGroup.Members.Where(m => m.IsForeign))
-				{
-					var foreign = await _dbEntities.ForeignAvatars.Match(a => a.ActorURI == member.AvatarId).ExecuteFirstAsync(token);
-					if (foreign == default)
-						continue;
-					remote.Add((foreign.ActorURI, $"{foreign.UserName}@{foreign.Domain}"));
-					inboxes.Add(foreign.InboxURL);
-				}
-				foreach (var member in dmGroup.Members.Where(m => !m.IsForeign && m.AvatarId != author.Id))
-				{
-					var local = await _localActors.FindById(LocalActorKind.Person, member.AvatarId, token);
-					if (local != default)
-						remote.Add((local.Uri, local.Handle));
-				}
-
-				var directNote = ActivityPubRenderer.DirectNote(dm, author, remote, dmGroup.ConversationURI);
-				var directCreate = ActivityPubRenderer.Create(author, directNote, $"create-{dm.ID}");
-				dm.ActivityURI = directCreate["id"]!.GetValue<string>();
-				dm.To = Strings(directNote["to"]);
-				dm.Mentions = remote.Select(r => new PostMention { ActorURI = r.Uri, Handle = "@" + r.Handle, IsLocal = r.Uri.StartsWith(author.BaseAddress + "/") }).ToList();
-				await DB.Default.SaveAsync(dm, token);
-				await DB.Default.Update<DmGroup>().MatchID(dmGroup.ID).Modify(g => g.UpdatedAt, DateTime.UtcNow).ExecuteAsync(token);
-				await _fanout.Distribute(dm, token);
-				if (inboxes.Count > 0)
-					await _delivery.Enqueue(author, inboxes, directCreate, token);
-
-				result.Data = ToView(dm);
-				return result;
-			}
-			catch (Exception ex)
-			{
-				_logger.LogError(ex, $"{nameof(PostsService)}.{nameof(InsertDm)}");
-				return result.Invalidate(_localizer["Something went wrong."], exception: ex);
-			}
 		}
 
 		public async Task<WebResult> GetDms(string rootUserId, string avatarId, string dmGroupId, CancellationToken token)
@@ -432,29 +191,24 @@ namespace PrivaPub.Services
 			}
 		}
 
-		async Task<GroupMember> ResolveRecipient(string recipient, CancellationToken token)
-		{
-			var handle = recipient.Trim().TrimStart('@');
-			if (!handle.Contains('@') || handle.EndsWith("@" + new Uri(_localActors.BaseAddress).Authority, StringComparison.OrdinalIgnoreCase))
-			{
-				var local = await _localActors.FindByUserName(handle.Split('@')[0], token);
-				return local is { Kind: LocalActorKind.Person } ? new GroupMember { AvatarId = local.Id } : default;
-			}
 
-			var actorUri = await _remoteActors.ResolveHandle(handle, token);
-			if (actorUri == default)
-				return default;
-			var foreign = await _remoteActors.GetActor(actorUri, refresh: false, token);
-			return foreign == default ? default : new GroupMember { AvatarId = foreign.ActorURI, IsForeign = true };
-		}
 
-		async Task<PostEntity> Parent(string answeringTo, CancellationToken token)
+		async Task<WebResult> Answer(Func<Task<StatusOutcome>> action, string operation)
 		{
-			if (string.IsNullOrEmpty(answeringTo))
+			var result = new WebResult();
-				return default;
+			try
-			return answeringTo.StartsWith("https://", StringComparison.OrdinalIgnoreCase)
+			{
-				? await _dbEntities.Posts.Match(p => p.ObjectURI == answeringTo).ExecuteFirstAsync(token)
+				var outcome = await action();
-				: await _dbEntities.Posts.MatchID(answeringTo).ExecuteFirstAsync(token);
+				if (!outcome.Ok)
+					return result.Invalidate(_localizer[outcome.Error], outcome.Status);
+				result.Data = ToView(outcome.Post);
+				return result;
+			}
+			catch (Exception ex)
+			{
+				_logger.LogError(ex, "{Service}.{Operation}", nameof(PostsService), operation);
+				return result.Invalidate(_localizer["Something went wrong."], exception: ex);
+			}
 		}
 
 		static PostVisibility LocalVisibility(string requested) => requested?.ToLowerInvariant() switch
@@ -464,19 +218,8 @@ namespace PrivaPub.Services
 			_ => PostVisibility.Public
 		};
 
-		static PostMention ToMention(ResolvedMention mention) => new()
-		{
-			ActorURI = mention.ActorUri,
-			Handle = "@" + mention.Handle,
-			IsLocal = mention.IsLocal,
-			AccountId = mention.AccountId
-		};
 
-		static string RemoteUri(string answeringTo) =>
-			answeringTo != default && answeringTo.StartsWith("https://", StringComparison.OrdinalIgnoreCase) ? answeringTo : default;
 
-		static List<string> Strings(JsonNode node) =>
-			node is JsonArray array ? array.Select(n => n?.GetValue<string>()).Where(s => s != default).ToList() : new List<string>();
 
 		async Task<LocalActor> OwnedAvatar(string rootUserId, string avatarId, CancellationToken token)
 		{

PrivaPub/Web/Pages/OAuth/Authorize.cshtml

@@ -0,0 +1,29 @@
+@page "/oauth/authorize"
+@model PrivaPub.Web.Pages.OAuth.AuthorizeModel
+@{
+	ViewData["Title"] = "Authorize";
+}
+<header><h1>Authorize @Model.ApplicationName</h1></header>
+<p>It asks for: <strong>@string.Join(", ", Model.RequestedScopes)</strong>.</p>
+@if (Model.Avatars.Count == 0)
+{
+	<p role="alert">This login has no persona yet. Create one first.</p>
+}
+else
+{
+	<form method="post">
+		@foreach (var parameter in Model.Parameters)
+		{
+			<input type="hidden" name="@parameter.Key" value="@parameter.Value">
+		}
+		<fieldset>
+			<legend>Act as</legend>
+			@foreach (var avatar in Model.Avatars)
+			{
+				<p><label><input type="radio" name="avatarId" value="@avatar.Id" required @(avatar == Model.Avatars[0] ? "checked" : "")> @avatar.Name <span class="meta">@@@avatar.Handle</span></label></p>
+			}
+		</fieldset>
+		<p class="meta">Each persona is a separate account to the application. Choosing one does not reveal the others.</p>
+		<p><button type="submit" name="decision" value="allow">Allow</button> <button type="submit" name="decision" value="deny">Deny</button></p>
+	</form>
+}

PrivaPub/Web/Pages/OAuth/Login.cshtml

@@ -0,0 +1,18 @@
+@page "/oauth/login"
+@model PrivaPub.Web.Pages.OAuth.LoginModel
+@{
+	ViewData["Title"] = "Sign in";
+}
+<header><h1>Sign in to PrivaPub</h1></header>
+<p class="meta">Sign in with your private login. You will then choose which persona the application acts as; the
+application never sees the login.</p>
+<form method="post">
+	<input type="hidden" name="ReturnUrl" value="@Model.ReturnUrl">
+	<p><label>Username<br><input name="UserName" autocomplete="username" required autofocus></label></p>
+	<p><label>Password<br><input name="Password" type="password" autocomplete="current-password" required></label></p>
+	@if (Model.Error != default)
+	{
+		<p role="alert">@Model.Error</p>
+	}
+	<p><button type="submit">Sign in</button></p>
+</form>

PrivaPub/Web/Pages/OAuth/OAuthPages.cs

@@ -0,0 +1,165 @@
+using Microsoft.AspNetCore;
+using Microsoft.AspNetCore.Authentication;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.RazorPages;
+using Microsoft.AspNetCore.RateLimiting;
+using Microsoft.IdentityModel.Tokens;
+
+using OpenIddict.Abstractions;
+using OpenIddict.Server.AspNetCore;
+
+using PrivaPub.Api.Mastodon.Auth;
+using PrivaPub.ClientModels;
+using PrivaPub.Federation.Actors;
+using PrivaPub.Infrastructure;
+using PrivaPub.Models.Federation;
+using PrivaPub.Models.User;
+using PrivaPub.Services;
+using PrivaPub.StaticServices;
+
+using System.Security.Claims;
+
+using static OpenIddict.Abstractions.OpenIddictConstants;
+
+namespace PrivaPub.Web.Pages.OAuth
+{
+	[EnableRateLimiting(RateLimiting.Accounts)]
+	public class LoginModel : PageModel
+	{
+		readonly IRootUsersService _users;
+
+		public LoginModel(IRootUsersService users)
+		{
+			_users = users;
+		}
+
+		[BindProperty(SupportsGet = true)]
+		public string ReturnUrl { get; set; }
+
+		public string Error { get; private set; }
+
+		public void OnGet() => Harden();
+
+		public async Task<IActionResult> OnPostAsync([FromForm] string userName, [FromForm] string password)
+		{
+			Harden();
+			if (string.IsNullOrEmpty(userName) || string.IsNullOrEmpty(password))
+			{
+				Error = "Enter your username and password.";
+				return Page();
+			}
+			var result = await _users.LoginAsync(new LoginForm { UserName = userName, Password = password });
+			if (!result.IsValid)
+			{
+				Error = "That username and password do not match.";
+				return Page();
+			}
+			var (root, _) = ((RootUser, ClientModels.User.ViewUserSettings))result.Data;
+			var identity = new ClaimsIdentity(new[] { new Claim(ClaimTypes.NameIdentifier, root.ID) }, OAuthSetup.LoginScheme);
+			await HttpContext.SignInAsync(OAuthSetup.LoginScheme, new ClaimsPrincipal(identity));
+
+			var target = ReturnUrl?.StartsWith("/oauth/authorize?", StringComparison.Ordinal) == true ? ReturnUrl : "/oauth/authorize";
+			return LocalRedirect(target + (target.Contains('?') ? "&" : "?") + "signed_in=1");
+		}
+
+		void Harden()
+		{
+			Response.Headers["Content-Security-Policy"] = "default-src 'none'; style-src 'unsafe-inline'; form-action 'self'; frame-ancestors 'none'";
+			Response.Headers["Cache-Control"] = "no-store";
+		}
+	}
+
+	[IgnoreAntiforgeryToken]
+	public class AuthorizeModel : PageModel
+	{
+		readonly DbEntities _dbEntities;
+		readonly ILocalActorService _localActors;
+		readonly OpenIddict.Abstractions.IOpenIddictApplicationManager _applications;
+
+		public AuthorizeModel(DbEntities dbEntities, ILocalActorService localActors, OpenIddict.Abstractions.IOpenIddictApplicationManager applications)
+		{
+			_dbEntities = dbEntities;
+			_localActors = localActors;
+			_applications = applications;
+		}
+
+		public string ApplicationName { get; private set; }
+		public IReadOnlyList<string> RequestedScopes { get; private set; } = Array.Empty<string>();
+		public IReadOnlyList<LocalActor> Avatars { get; private set; } = Array.Empty<LocalActor>();
+		public IReadOnlyList<KeyValuePair<string, string>> Parameters { get; private set; } = Array.Empty<KeyValuePair<string, string>>();
+
+		public async Task<IActionResult> OnGetAsync(CancellationToken token) => await Show(token);
+
+		public async Task<IActionResult> OnPostAsync([FromForm] string avatarId, [FromForm] string decision, CancellationToken token)
+		{
+			var request = HttpContext.GetOpenIddictServerRequest();
+			var rootId = await SignedInRoot();
+			if (request == default || rootId == default)
+				return await Show(token);
+
+			if (decision != "allow")
+				return Forbid(new AuthenticationProperties(new Dictionary<string, string>
+				{
+					[OpenIddictServerAspNetCoreConstants.Properties.Error] = Errors.AccessDenied,
+					[OpenIddictServerAspNetCoreConstants.Properties.ErrorDescription] = "The user denied the request."
+				}), OpenIddictServerAspNetCoreDefaults.AuthenticationScheme);
+
+			var owns = !string.IsNullOrEmpty(avatarId)
+				&& await _dbEntities.RootToAvatars.Match(r => r.RootId == rootId && r.AvatarId == avatarId).ExecuteAnyAsync(token);
+			var avatar = owns ? await _localActors.FindById(LocalActorKind.Person, avatarId, token) : default;
+			if (avatar == default)
+				return await Show(token);
+
+			var identity = new ClaimsIdentity(TokenValidationParameters.DefaultAuthenticationType, Claims.Name, Claims.Role);
+			identity.SetClaim(Claims.Subject, avatar.Id);
+			identity.SetClaim(Claims.Name, avatar.UserName);
+			identity.SetScopes(MastodonScopes.Parse(request.Scope));
+			identity.SetDestinations(_ => new[] { Destinations.AccessToken });
+			await HttpContext.SignOutAsync(OAuthSetup.LoginScheme);
+			return SignIn(new ClaimsPrincipal(identity), OpenIddictServerAspNetCoreDefaults.AuthenticationScheme);
+		}
+
+		async Task<IActionResult> Show(CancellationToken token)
+		{
+			var request = HttpContext.GetOpenIddictServerRequest();
+			if (request == default)
+				return BadRequest();
+
+			var rootId = await SignedInRoot();
+			var forceLogin = string.Equals((string)request["force_login"], "true", StringComparison.OrdinalIgnoreCase)
+				&& Request.Query["signed_in"] != "1";
+			if (rootId == default || forceLogin)
+			{
+				var query = string.Join("&", Request.Query.Where(q => q.Key != "signed_in").Select(q => $"{Uri.EscapeDataString(q.Key)}={Uri.EscapeDataString(q.Value.ToString())}"));
+				return Redirect($"/oauth/login?returnUrl={Uri.EscapeDataString("/oauth/authorize?" + query)}");
+			}
+
+			var application = await _applications.FindByClientIdAsync(request.ClientId, token);
+			ApplicationName = application == default ? "an application" : await _applications.GetDisplayNameAsync(application, token) ?? "an application";
+			RequestedScopes = MastodonScopes.Parse(request.Scope);
+			var avatarIds = (await _dbEntities.RootToAvatars.Match(r => r.RootId == rootId).ExecuteAsync(token)).Select(r => r.AvatarId).ToList();
+			var avatars = new List<LocalActor>();
+			foreach (var id in avatarIds)
+				if (await _localActors.FindById(LocalActorKind.Person, id, token) is { } avatar)
+					avatars.Add(avatar);
+			Avatars = avatars;
+			Parameters = request.GetParameters()
+				.Where(p => p.Key is not ("avatarId" or "decision" or "signed_in"))
+				.Select(p => new KeyValuePair<string, string>(p.Key, (string)p.Value))
+				.ToList();
+			Response.Headers["Content-Security-Policy"] = "default-src 'none'; style-src 'unsafe-inline'; frame-ancestors 'none'";
+			Response.Headers["Cache-Control"] = "no-store";
+			return Page();
+		}
+
+		async Task<string> SignedInRoot()
+		{
+			var login = await HttpContext.AuthenticateAsync(OAuthSetup.LoginScheme);
+			var rootId = login.Succeeded ? login.Principal.FindFirstValue(ClaimTypes.NameIdentifier) : default;
+			if (rootId == default)
+				return default;
+			var root = await _dbEntities.RootUsers.MatchID(rootId).ExecuteFirstAsync();
+			return root is { IsBanned: false, DeletedAt: null } ? rootId : default;
+		}
+	}
+}

PrivaPub/Web/Pages/Pages.cs

@@ -72,6 +72,7 @@ namespace PrivaPub.Web.Pages
 					? _dbEntities.Posts.Match(p => p.GroupId == Actor.Id)
 					: _dbEntities.Posts.Match(p => p.GroupUserId == Actor.Id && !p.IsFederatedCopy))
 				.Match(VisibilityPolicy.IsPublic)
+				.Match(p => p.ReblogOfPostId == null)
 				.Sort(p => p.ID, Order.Descending)
 				.Limit(PageSize)
 				.ExecuteAsync(token);
@@ -112,7 +113,7 @@ namespace PrivaPub.Web.Pages
 			if (Actor is not { IsFederated: true, Kind: LocalActorKind.Person })
 				return NotFound();
 			var post = await _dbEntities.Posts
-				.Match(p => p.ID == id && p.GroupUserId == Actor.Id && !p.IsFederatedCopy)
+				.Match(p => p.ID == id && p.GroupUserId == Actor.Id && !p.IsFederatedCopy && p.ReblogOfPostId == null)
 				.Match(VisibilityPolicy.IsPublic)
 				.ExecuteFirstAsync(token);
 			if (post == default)

docs/ROADMAP.md

@@ -6,7 +6,7 @@ Written 2026-10-01 from the original 2023 code, the decePubClient UI, a federati
 
 - [x] P0 Security baseline: v1.1.0, deployed and verified 2026-10-01
 - [x] P1.1 Infrastructure and content model: v1.2.0, deployed and verified 2026-10-01
-- [ ] P1.2 Social graph and timelines
+- [x] P1.2 Social graph and timelines: v1.3.0, deployed and verified 2026-10-01
 - [ ] P2 Mastodon client API
 - [ ] P3 Social features
 - [ ] P4 Groups and privacy features

tools/smoke/mastodon-api.sh

@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+# Checks the Mastodon client API the way a client first meets it.
+# usage: tools/smoke/mastodon-api.sh https://privapub.thepra.dev [ACCESS_TOKEN]
+set -euo pipefail
+BASE="${1:?base url}"; TOKEN="${2:-}"
+fail() { echo "::error::$*"; exit 1; }
+json() { python3 -c "import sys,json; d=json.load(sys.stdin); $1"; }
+
+version=$(curl -fsS "$BASE/api/v1/instance" | json "print(d['version'])") || fail "instance v1"
+curl -fsS "$BASE/api/v2/instance" | json "assert d['configuration']['statuses']['max_characters'] > 0" || fail "instance v2"
+curl -fsS "$BASE/.well-known/oauth-authorization-server" | json "assert d['token_endpoint'].endswith('/oauth/token')" || fail "oauth discovery"
+
+app=$(curl -fsS -X POST "$BASE/api/v1/apps" -d 'client_name=privapub-smoke&redirect_uris=urn:ietf:wg:oauth:2.0:oob&scopes=read') || fail "app registration"
+id=$(echo "$app" | json "print(d['client_id'])"); secret=$(echo "$app" | json "print(d['client_secret'])")
+app_token=$(curl -fsS -X POST "$BASE/oauth/token" -d "grant_type=client_credentials&client_id=$id&client_secret=$secret&scope=read" | json "print(d['access_token'])") || fail "client credentials"
+curl -fsS -H "Authorization: Bearer $app_token" "$BASE/api/v1/apps/verify_credentials" | json "assert d['name'] == 'privapub-smoke'" || fail "app verify_credentials"
+code=$(curl -s -o /dev/null -w '%{http_code}' -H "Authorization: Bearer $app_token" "$BASE/api/v1/accounts/verify_credentials")
+[ "$code" = "401" ] || fail "an app token reached a user endpoint ($code)"
+curl -fsS "$BASE/api/v1/timelines/public?limit=2" | json "assert isinstance(d, list)" || fail "public timeline"
+curl -fsS -X POST "$BASE/oauth/revoke" -d "token=$app_token&client_id=$id&client_secret=$secret" -o /dev/null || fail "revoke"
+
+if [ -n "$TOKEN" ]; then
+	curl -fsS -H "Authorization: Bearer $TOKEN" "$BASE/api/v1/accounts/verify_credentials" | json "assert d['source'] is not None" || fail "verify_credentials"
+	curl -fsS -H "Authorization: Bearer $TOKEN" "$BASE/api/v1/timelines/home?limit=5" | json "assert isinstance(d, list)" || fail "home"
+	curl -fsS -H "Authorization: Bearer $TOKEN" "$BASE/api/v1/notifications?limit=5" | json "assert isinstance(d, list)" || fail "notifications"
+fi
+echo "mastodon api ok: $version"