Small refactors

1 files changed, 339 insertions, 0 deletions

diff --git a/ExampleBots/MediaModeratorPoC/MediaModBot.cs b/ExampleBots/MediaModeratorPoC/MediaModBot.cs
new file mode 100644
index 0000000..0aacf61
--- /dev/null
+++ b/ExampleBots/MediaModeratorPoC/MediaModBot.cs
@@ -0,0 +1,339 @@
+using System.Security.Cryptography;
+using System.Text.RegularExpressions;
+using ArcaneLibs.Extensions;
+using LibMatrix;
+using LibMatrix.EventTypes.Spec;
+using LibMatrix.EventTypes.Spec.State;
+using LibMatrix.Helpers;
+using LibMatrix.Homeservers;
+using LibMatrix.Responses;
+using LibMatrix.RoomTypes;
+using LibMatrix.Services;
+using LibMatrix.Utilities.Bot.Interfaces;
+using MediaModeratorPoC.AccountData;
+using MediaModeratorPoC.StateEventTypes;
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+
+namespace MediaModeratorPoC;
+
+public class MediaModBot(AuthenticatedHomeserverGeneric hs, ILogger<MediaModBot> logger, MediaModBotConfiguration configuration,
+    HomeserverResolverService hsResolver) : IHostedService {
+    private readonly IEnumerable<ICommand> _commands;
+
+    private Task _listenerTask;
+
+    private GenericRoom _policyRoom;
+    private GenericRoom _logRoom;
+    private GenericRoom _controlRoom;
+
+
+
+    /// <summary>Triggered when the application host is ready to start the service.</summary>
+    /// <param name="cancellationToken">Indicates that the start process has been aborted.</param>
+    public async Task StartAsync(CancellationToken cancellationToken) {
+        _listenerTask = Run(cancellationToken);
+        logger.LogInformation("Bot started!");
+    }
+
+    private async Task Run(CancellationToken cancellationToken) {
+        Directory.GetFiles("bot_data/cache").ToList().ForEach(File.Delete);
+
+        BotData botData;
+
+        try {
+            botData = await hs.GetAccountDataAsync<BotData>("gay.rory.modbot_data");
+        }
+        catch (Exception e) {
+            if (e is not MatrixException { ErrorCode: "M_NOT_FOUND" }) {
+                logger.LogError("{}", e.ToString());
+                throw;
+            }
+
+            botData = new BotData();
+            var creationContent = CreateRoomRequest.CreatePrivate(hs, name: "Media Moderator PoC - Control room", roomAliasName: "media-moderator-poc-control-room");
+            creationContent.Invite = configuration.Admins;
+            creationContent.CreationContent["type"] = "gay.rory.media_moderator_poc.control_room";
+
+            botData.ControlRoom = (await hs.CreateRoom(creationContent)).RoomId;
+
+            //set access rules to allow joining via control room
+            creationContent.InitialState.Add(new StateEvent {
+                Type = "m.room.join_rules",
+                StateKey = "",
+                TypedContent = new RoomJoinRulesEventContent {
+                    JoinRule = "knock_restricted",
+                    Allow = new() {
+                        new RoomJoinRulesEventContent.AllowEntry {
+                            Type = "m.room_membership",
+                            RoomId = botData.ControlRoom
+                        }
+                    }
+                }
+            });
+
+            creationContent.Name = "Media Moderator PoC - Log room";
+            creationContent.RoomAliasName = "media-moderator-poc-log-room";
+            creationContent.CreationContent["type"] = "gay.rory.media_moderator_poc.log_room";
+            botData.LogRoom = (await hs.CreateRoom(creationContent)).RoomId;
+
+            creationContent.Name = "Media Moderator PoC - Policy room";
+            creationContent.RoomAliasName = "media-moderator-poc-policy-room";
+            creationContent.CreationContent["type"] = "gay.rory.media_moderator_poc.policy_room";
+            botData.PolicyRoom = (await hs.CreateRoom(creationContent)).RoomId;
+
+            await hs.SetAccountData("gay.rory.modbot_data", botData);
+        }
+
+        _policyRoom = hs.GetRoom(botData.PolicyRoom ?? botData.ControlRoom);
+        _logRoom = hs.GetRoom(botData.LogRoom ?? botData.ControlRoom);
+        _controlRoom = hs.GetRoom(botData.ControlRoom);
+        var syncHelper = new SyncHelper(hs);
+
+        List<string> admins = new();
+
+#pragma warning disable CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
+        Task.Run(async () => {
+            while (!cancellationToken.IsCancellationRequested) {
+                var controlRoomMembers = _controlRoom.GetMembersAsync();
+                await foreach (var member in controlRoomMembers) {
+                    if ((member.TypedContent as RoomMemberEventContent)?
+
+                        .Membership == "join") admins.Add(member.UserId);
+                }
+
+                await Task.Delay(TimeSpan.FromSeconds(30), cancellationToken);
+            }
+        }, cancellationToken);
+#pragma warning restore CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
+
+        syncHelper.InviteReceivedHandlers.Add(async Task (args) => {
+            var inviteEvent =
+                args.Value.InviteState.Events.FirstOrDefault(x =>
+                    x.Type == "m.room.member" && x.StateKey == hs.UserId);
+            logger.LogInformation("Got invite to {RoomId} by {Sender} with reason: {Reason}", args.Key, inviteEvent!.Sender, (inviteEvent.TypedContent as RoomMemberEventContent)!.Reason);
+            if (inviteEvent.Sender.EndsWith(":rory.gay") || inviteEvent!.Sender.EndsWith(":conduit.rory.gay")) {
+                try {
+                    var senderProfile = await hs.GetProfileAsync(inviteEvent.Sender);
+                    await hs.GetRoom(args.Key).JoinAsync(reason: $"I was invited by {senderProfile.DisplayName ?? inviteEvent.Sender}!");
+                }
+                catch (Exception e) {
+                    logger.LogError("{}", e.ToString());
+                    await hs.GetRoom(args.Key).LeaveAsync(reason: "I was unable to join the room: " + e);
+                }
+            }
+        });
+
+        syncHelper.TimelineEventHandlers.Add(async @event => {
+            var room = hs.GetRoom(@event.RoomId);
+            try {
+                logger.LogInformation(
+                    "Got timeline event in {}: {}", @event.RoomId, @event.ToJson(indent: true, ignoreNull: true));
+
+                if (@event is { Type: "m.room.message", TypedContent: RoomMessageEventContent message }) {
+                    if (message is { MessageType: "m.image" }) {
+                        //check media
+                        var matchedPolicy = await CheckMedia(@event);
+                        if (matchedPolicy is null) return;
+                        var matchedpolicyData = matchedPolicy.TypedContent as MediaPolicyEventContent;
+                        var recommendation = matchedpolicyData.Recommendation;
+                        await _logRoom.SendMessageEventAsync(
+                            new RoomMessageEventContent(
+                                body:
+                                $"User {MessageFormatter.HtmlFormatMention(@event.Sender)} posted an image in {MessageFormatter.HtmlFormatMention(room.RoomId)} that matched rule {matchedPolicy.StateKey}, applying action {matchedpolicyData.Recommendation}, as described in rule: {matchedPolicy.RawContent!.ToJson(ignoreNull: true)}",
+                                messageType: "m.text") {
+                                Format = "org.matrix.custom.html",
+                                FormattedBody =
+                                    $"<font color=\"#FFFF00\">User {MessageFormatter.HtmlFormatMention(@event.Sender)} posted an image in {MessageFormatter.HtmlFormatMention(room.RoomId)} that matched rule {matchedPolicy.StateKey}, applying action {matchedpolicyData.Recommendation}, as described in rule: <pre>{matchedPolicy.RawContent!.ToJson(ignoreNull: true)}</pre></font>"
+                            });
+                        switch (recommendation) {
+                            case "warn_admins": {
+                                await _controlRoom.SendMessageEventAsync(
+                                    new RoomMessageEventContent(
+                                        body: $"{string.Join(' ', admins)}\nUser {MessageFormatter.HtmlFormatMention(@event.Sender)} posted a banned image {message.Url}",
+                                        messageType: "m.text") {
+                                        Format = "org.matrix.custom.html",
+                                        FormattedBody = $"{string.Join(' ', admins.Select(u => MessageFormatter.HtmlFormatMention(u)))}\n" +
+                                                        $"<font color=\"#FF0000\">User {MessageFormatter.HtmlFormatMention(@event.Sender)} posted a banned image <a href=\"{message.Url}\">{message.Url}</a></font>"
+                                    });
+                                break;
+                            }
+                            case "warn": {
+                                await room.SendMessageEventAsync(
+                                    new RoomMessageEventContent(
+                                        body: $"Please be careful when posting this image: {matchedpolicyData.Reason ?? "No reason specified"}",
+                                        messageType: "m.text") {
+                                        Format = "org.matrix.custom.html",
+                                        FormattedBody =
+                                            $"<font color=\"#FFFF00\">Please be careful when posting this image: {matchedpolicyData.Reason ?? "No reason specified"}</a></font>"
+                                    });
+                                break;
+                            }
+                            case "redact": {
+                                await room.RedactEventAsync(@event.EventId, matchedpolicyData.Reason ?? "No reason specified");
+                                break;
+                            }
+                            case "spoiler": {
+                                // <blockquote>
+                                //  <a href=\"https://matrix.to/#/@emma:rory.gay\">@emma:rory.gay</a><br>
+                                //  <a href=\"https://codeberg.org/crimsonfork/CN\"></a>
+                                //  <font color=\"#dc143c\" data-mx-color=\"#dc143c\">
+                                //      <b>CN</b>
+                                //  </font>:
+                                //  <a href=\"https://the-apothecary.club/_matrix/media/v3/download/rory.gay/sLkdxUhipiQaFwRkXcPSRwdg\">test</a><br>
+                                //  <span data-mx-spoiler=\"\"><a href=\"https://the-apothecary.club/_matrix/media/v3/download/rory.gay/sLkdxUhipiQaFwRkXcPSRwdg\">
+                                //      <img src=\"mxc://rory.gay/sLkdxUhipiQaFwRkXcPSRwdg\" height=\"69\"></a>
+                                //  </span>
+                                // </blockquote>
+                                await room.SendMessageEventAsync(
+                                    new RoomMessageEventContent(
+                                        body:
+                                        $"Please be careful when posting this image: {matchedpolicyData.Reason}, I have spoilered it for you:",
+                                        messageType: "m.text") {
+                                        Format = "org.matrix.custom.html",
+                                        FormattedBody =
+                                            $"<font color=\"#FFFF00\">Please be careful when posting this image: {matchedpolicyData.Reason}, I have spoilered it for you:</a></font>"
+                                    });
+                                var imageUrl = message.Url;
+                                await room.SendMessageEventAsync(
+                                    new RoomMessageEventContent(body: $"CN: {imageUrl}",
+                                        messageType: "m.text") {
+                                        Format = "org.matrix.custom.html",
+                                        FormattedBody = $"""
+                                                             <blockquote>
+                                                                <font color=\"#dc143c\" data-mx-color=\"#dc143c\">
+                                                                    <b>CN</b>
+                                                                </font>:
+                                                                <a href=\"{imageUrl}\">{matchedpolicyData.Reason}</a><br>
+                                                                <span data-mx-spoiler=\"\">
+                                                                    <a href=\"{imageUrl}\">
+                                                                        <img src=\"{imageUrl}\" height=\"69\">
+                                                                    </a>
+                                                                </span>
+                                                             </blockquote>
+                                                         """
+                                    });
+                                await room.RedactEventAsync(@event.EventId, "Automatically spoilered: " + matchedpolicyData.Reason);
+                                break;
+                            }
+                            case "mute": {
+                                await room.RedactEventAsync(@event.EventId, matchedpolicyData.Reason);
+                                //change powerlevel to -1
+                                var currentPls = await room.GetPowerLevelsAsync();
+                                if(currentPls is null) {
+                                    logger.LogWarning("Unable to get power levels for {room}", room.RoomId);
+                                    await _logRoom.SendMessageEventAsync(
+                                        MessageFormatter.FormatError($"Unable to get power levels for {MessageFormatter.HtmlFormatMention(room.RoomId)}"));
+                                    return;
+                                }
+                                currentPls.Users ??= new();
+                                currentPls.Users[@event.Sender] = -1;
+                                await room.SendStateEventAsync("m.room.power_levels", currentPls);
+                                break;
+                            }
+                            case "kick": {
+                                await room.RedactEventAsync(@event.EventId, matchedpolicyData.Reason);
+                                await room.KickAsync(@event.Sender, matchedpolicyData.Reason);
+                                break;
+                            }
+                            case "ban": {
+                                await room.RedactEventAsync(@event.EventId, matchedpolicyData.Reason);
+                                await room.BanAsync(@event.Sender, matchedpolicyData.Reason);
+                                break;
+                            }
+                            default: {
+                                throw new ArgumentOutOfRangeException("recommendation",
+                                    $"Unknown response type {matchedpolicyData.Recommendation}!");
+                            }
+                        }
+                    }
+                }
+            }
+            catch (Exception e) {
+                logger.LogError("{}", e.ToString());
+                await _controlRoom.SendMessageEventAsync(
+                    MessageFormatter.FormatException($"Unable to ban user in {MessageFormatter.HtmlFormatMention(room.RoomId)}", e));
+                await _logRoom.SendMessageEventAsync(
+                    MessageFormatter.FormatException($"Unable to ban user in {MessageFormatter.HtmlFormatMention(room.RoomId)}", e));
+                await using var stream = new MemoryStream(e.ToString().AsBytes().ToArray());
+                await _controlRoom.SendFileAsync("error.log.cs", stream);
+                await _logRoom.SendFileAsync("error.log.cs", stream);
+            }
+        });
+    }
+
+    /// <summary>Triggered when the application host is performing a graceful shutdown.</summary>
+    /// <param name="cancellationToken">Indicates that the shutdown process should no longer be graceful.</param>
+    public async Task StopAsync(CancellationToken cancellationToken) {
+        logger.LogInformation("Shutting down bot!");
+    }
+
+    private async Task<StateEventResponse?> CheckMedia(StateEventResponse @event) {
+        var stateList = _policyRoom.GetFullStateAsync();
+        var hashAlgo = SHA3_256.Create();
+
+        var mxcUri = @event.RawContent["url"].GetValue<string>();
+        var resolvedUri = await hsResolver.ResolveMediaUri(mxcUri.Split('/')[2], mxcUri);
+        var uriHash = hashAlgo.ComputeHash(mxcUri.AsBytes().ToArray());
+        byte[]? fileHash = null;
+
+        try {
+            fileHash = await hashAlgo.ComputeHashAsync(await hs._httpClient.GetStreamAsync(resolvedUri));
+        }
+        catch (Exception ex) {
+            await _logRoom.SendMessageEventAsync(
+                MessageFormatter.FormatException($"Error calculating file hash for {mxcUri} via {mxcUri.Split('/')[2]} ({resolvedUri}), retrying via {hs.BaseUrl}...",
+                    ex));
+            try {
+                resolvedUri = await hsResolver.ResolveMediaUri(hs.BaseUrl, mxcUri);
+                fileHash = await hashAlgo.ComputeHashAsync(await hs._httpClient.GetStreamAsync(resolvedUri));
+            }
+            catch (Exception ex2) {
+                await _logRoom.SendMessageEventAsync(
+                    MessageFormatter.FormatException($"Error calculating file hash via {hs.BaseUrl} ({resolvedUri})!", ex2));
+            }
+        }
+
+        logger.LogInformation("Checking media {url} with hash {hash}", resolvedUri, fileHash);
+
+        await foreach (var state in stateList) {
+            if (state.Type != "gay.rory.media_moderator_poc.rule.media" && state.Type != "gay.rory.media_moderator_poc.rule.server") continue;
+            if (!state.RawContent.ContainsKey("entity")) {
+                logger.LogWarning("Rule {rule} has no entity, this event was probably redacted!", state.StateKey);
+                continue;
+            }
+
+            logger.LogInformation("Checking rule {rule}: {data}", state.StateKey, state.TypedContent.ToJson(ignoreNull: true, indent: false));
+            var rule = state.TypedContent as MediaPolicyEventContent;
+            if (state.Type == "gay.rory.media_moderator_poc.rule.server" && rule.ServerEntity is not null) {
+                rule.ServerEntity = rule.ServerEntity.Replace("\\*", ".*").Replace("\\?", ".");
+                var regex = new Regex($"mxc://({rule.ServerEntity})/.*", RegexOptions.Compiled | RegexOptions.IgnoreCase);
+                if (regex.IsMatch(@event.RawContent["url"]!.GetValue<string>())) {
+                    logger.LogInformation("{url} matched rule {rule}", @event.RawContent["url"], rule.ToJson(ignoreNull: true));
+                    return state;
+                }
+            }
+
+            if (rule.Entity is not null && uriHash.SequenceEqual(rule.Entity)) {
+                logger.LogInformation("{url} matched rule {rule} by uri hash", @event.RawContent["url"], rule.ToJson(ignoreNull: true));
+                return state;
+            }
+
+            logger.LogInformation("uri hash {uriHash} did not match rule's {ruleUriHash}", Convert.ToBase64String(uriHash), Convert.ToBase64String(rule.Entity));
+
+            if (rule.FileHash is not null && fileHash is not null && rule.FileHash.SequenceEqual(fileHash)) {
+                logger.LogInformation("{url} matched rule {rule} by file hash", @event.RawContent["url"], rule.ToJson(ignoreNull: true));
+                return state;
+            }
+
+            logger.LogInformation("file hash {fileHash} did not match rule's {ruleFileHash}", Convert.ToBase64String(fileHash), Convert.ToBase64String(rule.FileHash));
+
+            //check pixels every 10% of the way through the image using ImageSharp
+            // var image = Image.Load(await _hs._httpClient.GetStreamAsync(resolvedUri));
+        }
+
+        logger.LogInformation("{url} did not match any rules", @event.RawContent["url"]);
+
+        return null;
+    }
+}