event handler, claude bridge, frontmatter parser, rate limiter, full message loop

src/bin/send.rs

@@ -53,9 +53,13 @@ async fn main() -> anyhow::Result<()> {
     client.restore_session(session.user_session).await?;
 
     // need at least one sync so the client knows about joined rooms
-    client.sync_once(matrix_sdk::config::SyncSettings::default()).await?;
+    client
+        .sync_once(matrix_sdk::config::SyncSettings::default())
+        .await?;
 
-    let room = client.get_room(&room_id).context("room not found - has the bot joined it?")?;
+    let room = client
+        .get_room(&room_id)
+        .context("room not found - has the bot joined it?")?;
     let content = RoomMessageEventContent::text_plain(&message);
     room.send(content).await?;
 

src/main.rs

@@ -1,4 +1,5 @@
 use std::path::{Path, PathBuf};
+use std::sync::Arc;
 
 use anyhow::{Context, bail};
 use matrix_sdk::{
@@ -6,12 +7,16 @@ use matrix_sdk::{
     authentication::matrix::MatrixSession,
     config::SyncSettings,
     ruma::{
+        OwnedRoomId, OwnedUserId,
         api::client::filter::FilterDefinition,
-        events::room::message::{MessageType, OriginalSyncRoomMessageEvent},
+        events::room::message::{
+            MessageType, OriginalSyncRoomMessageEvent, RoomMessageEventContent,
+        },
     },
 };
 use serde::{Deserialize, Serialize};
 use tokio::fs;
+use tokio::sync::Mutex;
 use tracing_subscriber::EnvFilter;
 
 #[derive(Debug, Deserialize)]
@@ -30,8 +35,27 @@ struct PersistedSession {
     sync_token: Option<String>,
 }
 
+#[derive(Clone, Debug)]
+struct ChatMessage {
+    sender: OwnedUserId,
+    sender_name: String,
+    body: String,
+    is_self: bool,
+}
+
+struct DaemonState {
+    own_user_id: OwnedUserId,
+    room_history: std::collections::HashMap<OwnedRoomId, Vec<ChatMessage>>,
+    pending_rooms: Vec<OwnedRoomId>,
+    rate_budget: u32,
+    last_rate_reset: std::time::Instant,
+}
+
 const STATE_DIR: &str = "/persist/damocles-lab/state";
+const IDENTITY_DIR: &str = "/persist/damocles-lab/state/identity";
 const CONFIG_PATH: &str = "/persist/damocles-lab/config.json";
+const MAX_HISTORY: usize = 20;
+const RATE_LIMIT_PER_MIN: u32 = 2;
 
 #[tokio::main]
 async fn main() -> anyhow::Result<()> {
@@ -43,6 +67,7 @@ async fn main() -> anyhow::Result<()> {
 
     let state_dir = Path::new(STATE_DIR);
     fs::create_dir_all(state_dir).await?;
+    fs::create_dir_all(Path::new(IDENTITY_DIR)).await?;
 
     let session_file = state_dir.join("session.json");
     let db_path = state_dir.join("db");
@@ -54,7 +79,25 @@ async fn main() -> anyhow::Result<()> {
         (login(&config, &db_path, &session_file).await?, None)
     };
 
-    sync(client, sync_token, &session_file).await
+    let own_user_id = client.user_id().context("not logged in")?.to_owned();
+    tracing::info!(user = %own_user_id, "ready");
+
+    let state = Arc::new(Mutex::new(DaemonState {
+        own_user_id: own_user_id.clone(),
+        room_history: std::collections::HashMap::new(),
+        pending_rooms: Vec::new(),
+        rate_budget: RATE_LIMIT_PER_MIN,
+        last_rate_reset: std::time::Instant::now(),
+    }));
+
+    // spawn the processor that invokes claude for pending messages
+    let processor_state = state.clone();
+    let processor_client = client.clone();
+    tokio::spawn(async move {
+        process_loop(processor_state, processor_client).await;
+    });
+
+    sync(client, sync_token, &session_file, state).await
 }
 
 async fn load_config() -> anyhow::Result<Config> {
@@ -81,11 +124,7 @@ async fn restore_session(session_file: &Path) -> anyhow::Result<(Client, Option<
     Ok((client, session.sync_token))
 }
 
-async fn login(
-    config: &Config,
-    db_path: &Path,
-    session_file: &Path,
-) -> anyhow::Result<Client> {
+async fn login(config: &Config, db_path: &Path, session_file: &Path) -> anyhow::Result<Client> {
     tracing::info!(homeserver = %config.homeserver, user = %config.username, "logging in");
 
     let client = Client::builder()
@@ -121,6 +160,7 @@ async fn sync(
     client: Client,
     initial_sync_token: Option<String>,
     session_file: &Path,
+    state: Arc<Mutex<DaemonState>>,
 ) -> anyhow::Result<()> {
     tracing::info!("initial sync (ignoring past messages)");
 
@@ -131,7 +171,7 @@ async fn sync(
         sync_settings = sync_settings.token(token);
     }
 
-    // initial sync loop - retries on transient errors
+    // initial sync - ignore old messages
     loop {
         match client.sync_once(sync_settings.clone()).await {
             Ok(response) => {
@@ -147,9 +187,14 @@ async fn sync(
 
     tracing::info!("synced, listening for messages");
 
-    client.add_event_handler(on_room_message);
+    // register event handler with shared state
+    client.add_event_handler(move |event: OriginalSyncRoomMessageEvent, room: Room| {
+        let state = state.clone();
+        async move {
+            on_room_message(event, room, state).await;
+        }
+    });
 
-    // main sync loop
     client.sync(sync_settings).await?;
 
     bail!("sync loop exited unexpectedly")
@@ -163,7 +208,11 @@ async fn persist_sync_token(session_file: &Path, sync_token: String) -> anyhow::
     Ok(())
 }
 
-async fn on_room_message(event: OriginalSyncRoomMessageEvent, room: Room) {
+async fn on_room_message(
+    event: OriginalSyncRoomMessageEvent,
+    room: Room,
+    state: Arc<Mutex<DaemonState>>,
+) {
     if room.state() != RoomState::Joined {
         return;
     }
@@ -171,16 +220,246 @@ async fn on_room_message(event: OriginalSyncRoomMessageEvent, room: Room) {
         return;
     };
 
+    let room_id = room.room_id().to_owned();
     let room_name = room
         .display_name()
         .await
         .map(|n| n.to_string())
-        .unwrap_or_else(|_| room.room_id().to_string());
+        .unwrap_or_else(|_| room_id.to_string());
+
+    let mut state = state.lock().await;
+    let is_self = event.sender == state.own_user_id;
+
+    let msg = ChatMessage {
+        sender: event.sender.clone(),
+        sender_name: event.sender.localpart().to_owned(),
+        body: text_content.body.clone(),
+        is_self,
+    };
 
     tracing::info!(
         room = %room_name,
         sender = %event.sender,
+        self_msg = is_self,
         "{}",
         text_content.body
     );
+
+    // add to history
+    let history = state.room_history.entry(room_id.clone()).or_default();
+    history.push(msg);
+    if history.len() > MAX_HISTORY {
+        history.drain(..history.len() - MAX_HISTORY);
+    }
+
+    // only invoke claude for non-self messages
+    if !is_self && !state.pending_rooms.contains(&room_id) {
+        state.pending_rooms.push(room_id);
+    }
+}
+
+async fn process_loop(state: Arc<Mutex<DaemonState>>, client: Client) {
+    loop {
+        tokio::time::sleep(std::time::Duration::from_secs(1)).await;
+
+        let room_id = {
+            let mut state = state.lock().await;
+
+            // reset rate budget every 60s
+            if state.last_rate_reset.elapsed() >= std::time::Duration::from_secs(60) {
+                state.rate_budget = RATE_LIMIT_PER_MIN;
+                state.last_rate_reset = std::time::Instant::now();
+            }
+
+            if state.rate_budget == 0 {
+                continue;
+            }
+
+            state.pending_rooms.pop()
+        };
+
+        let Some(room_id) = room_id else {
+            continue;
+        };
+
+        let history = {
+            let state = state.lock().await;
+            state
+                .room_history
+                .get(&room_id)
+                .cloned()
+                .unwrap_or_default()
+        };
+
+        let room_name = client
+            .get_room(&room_id)
+            .and_then(|r| {
+                // can't easily get display_name synchronously, use room_id
+                Some(r.room_id().to_string())
+            })
+            .unwrap_or_else(|| room_id.to_string());
+
+        match invoke_claude(&room_id, &room_name, &history).await {
+            Ok(Some(response)) => {
+                if let Some(room) = client.get_room(&response.room) {
+                    let content = RoomMessageEventContent::text_plain(&response.body);
+                    match room.send(content).await {
+                        Ok(_) => {
+                            let mut state = state.lock().await;
+                            state.rate_budget = state.rate_budget.saturating_sub(1);
+                            tracing::info!(
+                                room = %response.room,
+                                "sent response ({} budget remaining)",
+                                state.rate_budget
+                            );
+                        }
+                        Err(e) => tracing::error!("failed to send: {e}"),
+                    }
+                } else {
+                    tracing::warn!(room = %response.room, "target room not found");
+                }
+            }
+            Ok(None) => {
+                tracing::debug!(room = %room_id, "claude chose to skip");
+            }
+            Err(e) => {
+                tracing::error!(room = %room_id, "claude invocation failed: {e}");
+            }
+        }
+    }
+}
+
+struct ClaudeResponse {
+    room: OwnedRoomId,
+    body: String,
+}
+
+async fn invoke_claude(
+    source_room: &OwnedRoomId,
+    room_name: &str,
+    history: &[ChatMessage],
+) -> anyhow::Result<Option<ClaudeResponse>> {
+    // build the prompt with conversation context
+    let mut prompt = String::new();
+    prompt.push_str(&format!("[room: {} ({})]\n", source_room, room_name));
+    prompt.push_str("[new messages below this line]\n");
+
+    for msg in history {
+        let prefix = if msg.is_self { "(you) " } else { "" };
+        prompt.push_str(&format!("{}{}: {}\n", prefix, msg.sender, msg.body));
+    }
+
+    tracing::debug!("invoking claude with {} messages", history.len());
+
+    let output = tokio::process::Command::new("claude")
+        .args([
+            "--print",
+            "--bare",
+            "--add-dir",
+            IDENTITY_DIR,
+            "--allowedTools",
+            "Read Edit Write Glob Grep",
+        ])
+        .current_dir(IDENTITY_DIR)
+        .arg(&prompt)
+        .output()
+        .await
+        .context("failed to run claude")?;
+
+    if !output.status.success() {
+        let stderr = String::from_utf8_lossy(&output.stderr);
+        bail!("claude exited with {}: {}", output.status, stderr);
+    }
+
+    let raw = String::from_utf8_lossy(&output.stdout).to_string();
+    parse_response(&raw, source_room)
+}
+
+fn parse_response(raw: &str, default_room: &OwnedRoomId) -> anyhow::Result<Option<ClaudeResponse>> {
+    let trimmed = raw.trim();
+
+    // check for frontmatter
+    if trimmed.starts_with("---") {
+        let parts: Vec<&str> = trimmed.splitn(3, "---").collect();
+        if parts.len() >= 3 {
+            let frontmatter = parts[1].trim();
+            let body = parts[2].trim();
+
+            // check for skip
+            if frontmatter.contains("skip: true") || frontmatter.contains("skip:true") {
+                return Ok(None);
+            }
+
+            // extract room override
+            let room = frontmatter
+                .lines()
+                .find(|l| l.starts_with("room:"))
+                .and_then(|l| l.strip_prefix("room:"))
+                .and_then(|r| r.trim().parse().ok())
+                .unwrap_or_else(|| default_room.clone());
+
+            if body.is_empty() {
+                return Ok(None);
+            }
+
+            return Ok(Some(ClaudeResponse {
+                room,
+                body: body.to_owned(),
+            }));
+        }
+    }
+
+    // no frontmatter - treat entire output as message to default room
+    if trimmed.is_empty() {
+        return Ok(None);
+    }
+
+    Ok(Some(ClaudeResponse {
+        room: default_room.clone(),
+        body: trimmed.to_owned(),
+    }))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn test_room() -> OwnedRoomId {
+        "!test:example.com".parse().unwrap()
+    }
+
+    #[test]
+    fn parse_frontmatter_response() {
+        let raw = "---\nroom: !other:server\n---\nhello world";
+        let resp = parse_response(raw, &test_room()).unwrap().unwrap();
+        assert_eq!(resp.room.as_str(), "!other:server");
+        assert_eq!(resp.body, "hello world");
+    }
+
+    #[test]
+    fn parse_skip_response() {
+        let raw = "---\nskip: true\n---\n";
+        assert!(parse_response(raw, &test_room()).unwrap().is_none());
+    }
+
+    #[test]
+    fn parse_plain_response() {
+        let raw = "just a message";
+        let resp = parse_response(raw, &test_room()).unwrap().unwrap();
+        assert_eq!(resp.room, test_room());
+        assert_eq!(resp.body, "just a message");
+    }
+
+    #[test]
+    fn parse_empty_response() {
+        assert!(parse_response("", &test_room()).unwrap().is_none());
+        assert!(parse_response("   \n  ", &test_room()).unwrap().is_none());
+    }
+
+    #[test]
+    fn parse_default_room() {
+        let raw = "---\n---\nhello";
+        let resp = parse_response(raw, &test_room()).unwrap().unwrap();
+        assert_eq!(resp.room, test_room());
+    }
 }