soulseek-rs-lib 13.0.0

use crate::{
    actor::server_actor::ServerMessage,
    message::{Message, MessageHandler},
};
use std::sync::mpsc::Sender;

pub struct JoinRoomHandler;

impl MessageHandler<ServerMessage> for JoinRoomHandler {
    fn get_code(&self) -> u8 {
        14
    }

    fn handle(&self, message: &mut Message, sender: Sender<ServerMessage>) {
        // JoinRoom (code 14): room name, then a vector of member usernames.
        // Per-user stat vectors follow but are not needed here, so we stop
        // after reading the names.
        let room = message.read_string();
        let user_count = message.read_int32();
        let mut users = Vec::new();
        for _ in 0..user_count {
            // Guard against a hostile user_count outrunning the payload; each
            // username is a length-prefixed string (>= 4 bytes).
            if message.get_pointer() + 4 > message.get_size() {
                break;
            }
            users.push(message.read_string());
        }
        let _ = sender.send(ServerMessage::RoomJoined { room, users });
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::message::framed;

    #[test]
    fn hostile_user_count_does_not_hang() {
        // room="" then user_count=u32::MAX with no usernames: must return
        // promptly instead of looping ~4 billion times.
        let (tx, rx) = std::sync::mpsc::channel();
        let mut message = framed(|m| {
            m.write_string("").write_int32(u32::MAX);
        });

        JoinRoomHandler.handle(&mut message, tx);
        match rx.try_recv() {
            Ok(ServerMessage::RoomJoined { users, .. }) => {
                assert!(users.is_empty());
            }
            other => panic!("unexpected: {other:?}"),
        }
    }

    #[test]
    fn forwards_room_and_member_list() {
        let (tx, rx) = std::sync::mpsc::channel();
        let mut message = framed(|m| {
            m.write_string("nicotine")
                .write_int32(2)
                .write_string("alice")
                .write_string("bob");
        });

        JoinRoomHandler.handle(&mut message, tx);
        match rx.try_recv() {
            Ok(ServerMessage::RoomJoined { room, users }) => {
                assert_eq!(room, "nicotine");
                assert_eq!(users, vec!["alice", "bob"]);
            }
            other => panic!("unexpected: {other:?}"),
        }
    }
}