From 7a1f8b51779ed8a6112fc83d13d81c3efdf792b7 Mon Sep 17 00:00:00 2001
From: Rory& <root@rory.gay>
Date: Thu, 13 Mar 2025 11:50:16 +0100
Subject: Initial commit

---
 MatrixInviteLogger/InviteLogger.cs | 117 +++++++++++++++++++++++++++++++++++++
 1 file changed, 117 insertions(+)
 create mode 100644 MatrixInviteLogger/InviteLogger.cs

(limited to 'MatrixInviteLogger/InviteLogger.cs')

diff --git a/MatrixInviteLogger/InviteLogger.cs b/MatrixInviteLogger/InviteLogger.cs
new file mode 100644
index 0000000..22a519b
--- /dev/null
+++ b/MatrixInviteLogger/InviteLogger.cs
@@ -0,0 +1,117 @@
+using System.Text.Json;
+using System.Text.Json.Nodes;
+using ArcaneLibs;
+using ArcaneLibs.Extensions;
+using LibMatrix.EventTypes.Spec.State.RoomInfo;
+using LibMatrix.Helpers;
+using LibMatrix.Utilities.Bot.Services;
+using MatrixInviteLogger;
+
+public class InviteLogger(ILogger<InviteLogger> logger, InviteLoggerConfiguration config) : InviteHandlerHostedService.IInviteHandler
+{
+    public async Task HandleInviteAsync(InviteHandlerHostedService.InviteEventArgs invite)
+    {
+        logger.LogInformation("Received invite to room {}", invite.RoomId);
+        var logRoom = invite.Homeserver.GetRoom(config.LogRoom);
+        var inviterName = await GetInviterNameAsync(invite);
+        string roomName = await GetRoomNameAsync(invite);
+
+        logger.LogInformation("Inviter: {}, Room: {}", inviterName, roomName);
+
+        var message = new MessageBuilder()
+            .WithBody("Received invite to ").WithMention(invite.RoomId, roomName).WithBody(" from ").WithMention(invite.MemberEvent.Sender!, inviterName)
+            .Build();
+
+        // TODO: can we filter this somehow to stay within event size limits?
+        // var serialisedInviteData = JsonNode.Parse(invite.InviteData.ToJson(ignoreNull: true));
+        // message.AdditionalData!["gay.rory.invite_logger.invite_data"] = serialisedInviteData!;
+
+        var inviteData = invite.InviteData.ToJsonUtf8Bytes();
+        var inviteDataFileUri = await invite.Homeserver.UploadFile(invite.RoomId + ".json", inviteData, "application/json");
+        logger.LogInformation("Uploaded invite data ({}) to {}", Util.BytesToString(inviteData.Length), inviteDataFileUri);
+        
+        // Dictionary<string, JsonElement>
+        message.AdditionalData!["gay.rory.invite_logger.invite_data_uri"] = JsonDocument.Parse($"\"{inviteDataFileUri}\"").RootElement;
+
+        await logRoom.SendMessageEventAsync(message);
+
+        if (config.SendInviteDataAsFile)
+        {
+            await logRoom.SendMessageEventAsync(new()
+            {
+                MessageType = "m.file",
+                Body = invite.RoomId + ".json",
+                FileName = invite.RoomId + ".json",
+                Url = inviteDataFileUri,
+                FileInfo = new() { Size = inviteData.Length, MimeType = "application/json" }
+            });
+        }
+    }
+
+    private async Task<string> GetInviterNameAsync(InviteHandlerHostedService.InviteEventArgs invite)
+    {
+        var name = invite.InviteData.InviteState?.Events?
+            .FirstOrDefault(evt => evt is { Type: RoomMemberEventContent.EventId } && evt.StateKey == invite.MemberEvent.Sender)?
+            .ContentAs<RoomMemberEventContent>()?.DisplayName;
+
+        if (!string.IsNullOrWhiteSpace(name))
+            return name;
+
+        try
+        {
+            await invite.Homeserver.GetProfileAsync(invite.MemberEvent.Sender!);
+        }
+        catch
+        {
+            //ignored
+        }
+
+        return invite.MemberEvent.Sender!;
+    }
+
+    private async Task<string> GetRoomNameAsync(InviteHandlerHostedService.InviteEventArgs invite)
+    {
+        // try get room name from invite state
+        var name = invite.InviteData.InviteState?.Events?
+            .FirstOrDefault(evt => evt is { Type: RoomNameEventContent.EventId, StateKey: "" })?
+            .ContentAs<RoomNameEventContent>()?.Name;
+
+        if (!string.IsNullOrWhiteSpace(name))
+            return name;
+
+        // try get room alias
+        var alias = invite.InviteData.InviteState?.Events?
+            .FirstOrDefault(evt => evt is { Type: RoomCanonicalAliasEventContent.EventId, StateKey: "" })?
+            .ContentAs<RoomCanonicalAliasEventContent>()?.Alias;
+
+        if (!string.IsNullOrWhiteSpace(alias))
+            return alias;
+
+        // try get room name via public previews
+        try
+        {
+            name = await invite.Homeserver.GetRoom(invite.RoomId).GetNameOrFallbackAsync();
+            if (name != invite.RoomId && !string.IsNullOrWhiteSpace(name))
+                return name;
+        }
+        catch
+        {
+            //ignored
+        }
+
+        // fallback to room alias via public previews
+        try
+        {
+            alias = (await invite.Homeserver.GetRoom(invite.RoomId).GetCanonicalAliasAsync())?.Alias;
+            if (!string.IsNullOrWhiteSpace(alias))
+                return alias;
+        }
+        catch
+        {
+            //ignored
+        }
+
+        // fall back to room ID
+        return invite.RoomId;
+    }
+}
\ No newline at end of file
-- 
cgit 1.5.1