Add autojoin

src/bot_commands.rs

@@ -3,6 +3,7 @@
 use anyhow::Context;
 use file_format::FileFormat;
 use futures_util::pin_mut;
+use futures_util::StreamExt;
 use image::io::Reader as ImageReader;
 use image::GenericImageView;
 use matrix_sdk::deserialized_responses::MemberEvent;
@@ -32,7 +33,6 @@ use time::macros::offset;
 use time::Duration;
 use time::OffsetDateTime;
 use time::Weekday;
-use futures_util::StreamExt;
 
 use crate::member_updates::MemberChanges;
 use crate::utils::avatar_http_url;
@@ -168,7 +168,9 @@ async fn name_changes_command(
             let stream = MemberChanges::new_stream(room, event.clone()).peekable();
             pin_mut!(stream);
             while let Some(event) = stream.next().await {
-                if count <= -5 { break; }
+                if count <= -5 {
+                    break;
+                }
 
                 let prev_event = stream.as_mut().peek().await;
                 let detail = prev_event.map(|e| e.content.details());
@@ -246,7 +248,9 @@ async fn avatar_changes_command(
             let stream = MemberChanges::new_stream(room, event.clone()).peekable();
             pin_mut!(stream);
             while let Some(event) = stream.next().await {
-                if count <= -5 { break; }
+                if count <= -5 {
+                    break;
+                }
 
                 let prev_event = stream.as_mut().peek().await;
                 let detail = prev_event.map(|e| e.content.details());
@@ -287,7 +291,9 @@ async fn avatar_changes_command(
                             avatar_http_url(event.content.avatar_url.as_deref(), homeserver)?;
                         let result = format!(
                             "{count}: Joined with avatar {}\n",
-                            avatar_link.map(|link| link.to_string()).unwrap_or("(No avatar)".to_string())
+                            avatar_link
+                                .map(|link| link.to_string())
+                                .unwrap_or("(No avatar)".to_string())
                         );
                         body.push_str(&result);
                     }

src/callbacks.rs

@@ -5,6 +5,7 @@ use crate::FuukaBotContext;
 use crate::FuukaBotError;
 use matrix_sdk::event_handler::Ctx;
 use matrix_sdk::room::Room;
+use matrix_sdk::ruma::events::room::member::StrippedRoomMemberEvent;
 use matrix_sdk::ruma::events::room::message::sanitize::remove_plain_reply_fallback;
 use matrix_sdk::ruma::events::room::message::RoomMessageEventContent;
 use matrix_sdk::ruma::events::room::message::{
@@ -45,6 +46,31 @@ impl FuukaBotCallbacks {
 
         Ok(())
     }
+
+    pub async fn on_stripped_member(ev: StrippedRoomMemberEvent, room: Room) {
+        let client = room.client();
+        let user_id = client.user_id().unwrap();
+        if ev.state_key != user_id {
+            return;
+        }
+
+        tokio::spawn(async move {
+            let room_id = room.room_id();
+            tracing::info!("Autojoining room {}", room_id);
+            let mut delay = 2;
+            while let Err(e) = room.join().await {
+                use tokio::time::{sleep, Duration};
+                tracing::warn!("Failed to join room {room_id} ({e:?}), retrying in {delay}s");
+                sleep(Duration::from_secs(delay)).await;
+                delay *= 2;
+
+                if delay > 3600 {
+                    tracing::error!("Can't join room {room_id} ({e:?})");
+                    break;
+                }
+            }
+        });
+    }
 }
 
 async fn send_error_message(

src/utils.rs

@@ -73,9 +73,7 @@ pub fn make_divergence(room_hash: u32, event_id_hash: Option<u32>) -> f32 {
 
 /// Given a [nom::error::Error] and the input, returns the [RoomMessageEventContent] to send to the room
 pub fn nom_error_message(input: &str, e: nom::error::Error<String>) -> RoomMessageEventContent {
-    let offset = input
-        .rfind(e.input.as_str())
-        .unwrap_or(e.input.len());
+    let offset = input.rfind(e.input.as_str()).unwrap_or(e.input.len());
     let (prefix, suffix) = input.split_at(offset);
     let prefix_parts = prefix.split('\n').collect::<Vec<_>>();
     let line_number = prefix_parts.len();