use protocol::messages::{
    HWProtocolMessage::{self, Rnd},
    HWServerMessage::{self, ChatMsg},
};
use rand::{self, Rng};
use server::{
    actions::Action,
    room::HWRoom,
    server::HWServer
};

pub fn rnd_action(options: Vec<String>, room: Option<&mut HWRoom>) -> Vec<Action> {
    if let Some(room) = room {
        let msg = rnd_reply(options);
        vec![msg.send_all().in_room(room.id).action()]
    } else {
        Vec::new()
    }
}

fn rnd_reply(options: Vec<String>) -> HWServerMessage {
    let options = if options.is_empty() {
        vec!["heads".to_owned(), "tails".to_owned()]
    } else {
        options
    };
    let reply = rand::thread_rng().choose(&options).unwrap();
    let msg = ChatMsg {
        nick: "[random]".to_owned(),
        msg: reply.clone(),
    };
    msg
}

#[cfg(test)]
mod tests {
    use super::*;
    use protocol::messages::HWServerMessage::ChatMsg;
    use server::actions::{
        Action::{self, Send}, PendingMessage,
    };

    fn reply2string(r: HWServerMessage) -> String {
        match r {
            ChatMsg { msg: p, .. } => String::from(p),
            _ => panic!("expected a ChatMsg"),
        }
    }

    fn run_handle_test(opts: Vec<String>) {
        let opts2 = opts.clone();
        for opt in opts {
            while reply2string(rnd_reply(opts2.clone())) != opt {}
        }
    }

    #[test]
    fn test_handle_rnd_empty() {
        run_handle_test(vec![])
    }

    #[test]
    fn test_handle_rnd_nonempty() {
        run_handle_test(vec!["A".to_owned(), "B".to_owned(), "C".to_owned()])
    }
}