//! Matrix event handlers: incoming room messages fire a hyperhive
//! wake signal so the agent's harness drives a new claude turn.
//!
//! Per mara on #548: wake body is a SHORT TEASER, not the full message
//! (msg stays unread server-side; agent fetches via `read_room`). The
//! `wake::format_wake_body` truncates to ~100 chars.
//!
//! Self-events (events sent by this agent) are filtered out so an
//! agent posting a message doesn't wake itself.

use std::path::PathBuf;
use std::sync::Arc;

use matrix_sdk::{
    Client, Room, RoomState,
    ruma::events::room::member::{MembershipState, StrippedRoomMemberEvent},
    ruma::events::room::message::{MessageType, OriginalSyncRoomMessageEvent},
};

use crate::{handlers, wake};

/// Install the room-message handler on `client`. Fires on every
/// `m.room.message` event in a joined room; non-self messages trigger
/// a wake signal to the hyperhive harness via the unix socket at
/// `hyperhive_socket`. The wake body summarises ALL rooms with unread
/// notifications at wake time (not just the triggering event) so the
/// agent receives a full picture in one prompt.
pub fn install_message_handler(client: &Client, hyperhive_socket: PathBuf) {
    let socket = Arc::new(hyperhive_socket);
    let own_user = client.user_id().map(std::borrow::ToOwned::to_owned);
    client.add_event_handler({
        let socket = socket.clone();
        move |event: OriginalSyncRoomMessageEvent, room: Room, client: Client| {
            let socket = socket.clone();
            let own_user = own_user.clone();
            async move {
                if room.state() != RoomState::Joined {
                    return;
                }
                // Self-event filter so the agent's own outgoing messages
                // don't wake it. matches forge_notify's self-skip pattern.
                if own_user.as_ref().is_some_and(|u| u == &event.sender) {
                    return;
                }
                // Build a wake body that covers all rooms with unread
                // notifications, not just the triggering event. This lets
                // the agent see the full backlog in a single wake prompt.
                // Falls back to the per-event teaser if the collect fails
                // (empty result means daemon is not seeing any unread yet —
                // unlikely but possible during a sync race).
                let unread = handlers::collect_unread(&client).await;
                let body = if unread.is_empty() {
                    // Sync hasn't updated notification counts yet; fall back
                    // to the current event so the agent still wakes.
                    let text = match &event.content.msgtype {
                        MessageType::Text(t) => t.body.clone(),
                        MessageType::Notice(n) => n.body.clone(),
                        MessageType::Emote(e) => format!("* {}", e.body),
                        _ => format!("[{}]", event.content.msgtype()),
                    };
                    let room_label = room
                        .canonical_alias()
                        .map_or_else(|| room.room_id().to_string(), |a| a.to_string());
                    wake::format_wake_body(event.sender.as_str(), &room_label, &text)
                } else {
                    wake::format_unread_summary(&unread)
                };
                if let Err(e) = wake::send_wake(&socket, &body).await {
                    tracing::warn!(error = %e, "failed to deliver matrix wake to hyperhive");
                } else {
                    tracing::debug!(room = %room.room_id(), "matrix wake delivered");
                }
            }
        }
    });
    tracing::info!("matrix message handler installed");
}

/// Install a handler that wakes the agent when a room invite arrives.
/// The agent decides whether to accept by calling `join_room`.
///
/// When the daemon receives an `m.room.member` state event with
/// `membership: invite` for the agent's own user ID during sync, it
/// fires a hyperhive wake so the agent can inspect the invite via
/// `list_invites` and act on it with `join_room`.
///
/// This closes the gap where invites accumulated in `invited_rooms()`
/// forever without the agent being notified — the daemon's message
/// handler only fires for joined rooms.
pub fn install_invite_handler(client: &Client, hyperhive_socket: PathBuf) {
    let socket = Arc::new(hyperhive_socket);
    let own_user = client.user_id().map(std::borrow::ToOwned::to_owned);
    client.add_event_handler({
        move |event: StrippedRoomMemberEvent, room: Room, client: Client| {
            let socket = socket.clone();
            let own_user = own_user.clone();
            async move {
                // Only handle invite events for our own user.
                if event.content.membership != MembershipState::Invite {
                    return;
                }
                let is_ours = own_user
                    .as_ref()
                    .is_some_and(|u| u.as_str() == event.state_key.as_str());
                if !is_ours {
                    return;
                }
                let room_id = room.room_id().to_owned();
                let label = room.name().unwrap_or_else(|| room_id.to_string());
                tracing::info!(%room_id, "matrix: received room invite, waking agent");
                // Refresh loose-ends BEFORE waking so the invite is
                // visible in get_loose_ends during the agent's turn.
                handlers::refresh_invite_loose_ends(&client).await;
                let body = format!(
                    "[matrix] invited to {label} ({room_id}) — \
                     use list_invites to see pending invites, join_room to accept"
                );
                if let Err(e) = wake::send_wake(&socket, &body).await {
                    tracing::warn!(
                        error = %e,
                        "matrix: failed to deliver invite-wake to hyperhive"
                    );
                }
            }
        }
    });
    tracing::info!("matrix invite handler installed");
}