use std::collections::HashMap;
use std::cell::RefCell;
// use std::io;
// use std::cell::{Ref, RefMut};


struct Player {
    id: u32,
    room_id: u32,
}

impl Player {
    pub fn writeln<T: AsRef<str>>(&mut self, msg: T) {
    }
}

struct PlayerStore {
    players: HashMap<u32, RefCell<Player>>,
}

impl PlayerStore {
    pub fn for_each_in_room(&self, room_id: u32, per_player: impl Fn(&mut Player) -> ()) {
        self.players.iter()
            .filter(|(_pid, p)| p.borrow().room_id == room_id)
            .for_each(|(_pid, p)| per_player(&mut p.borrow_mut()));
    }
}

fn main() -> () {
    let player_store = PlayerStore {
        players: HashMap::new()
    };

    let my_room_id = 5;
    player_store.for_each_in_room(
        my_room_id,
        |other_player| {
            if other_player.id != 44 {
                other_player.writeln(format!("{} says: {}", "hey", "hello"));
            }
        }
    );


}