use prost::Message;

use crate::protocol::{
    LoginRequest, LoginResponse, MessageType, RequestResult, SignupRequest, SignupResponse,
};

pub(crate) fn dispatch_message(msg_type: u8, msg: &[u8]) -> Vec<u8> {
    let mut buf = Vec::new();

    match msg_type {
        // Owing to Rust disallows converting an integer to an
        // enumeration (yet allows in reverse! ಠ_ಠ), we have to
        // use such this way to make this pattern matching works.
        //
        // This seems not as elegable as what we are expected,
        // but it could work well, provided that items in
        // `MessageType` doesn't excceed 256.
        val if val == MessageType::LoginRequest as u8 => {
            let msg = LoginRequest::decode(msg).unwrap();

            log::info!("{msg:?}");

            LoginResponse {
                result: RequestResult::Success.into(),
                message: "Successfully logged in!".into(),
            }
            .encode(&mut buf)
            .unwrap();

            [vec![MessageType::LoginResponse as u8], buf].concat()
        }
        val if val == MessageType::SignupRequest as u8 => {
            let msg = SignupRequest::decode(msg).unwrap();

            log::info!("{msg:?}");

            SignupResponse {
                result: RequestResult::Success.into(),
                message: "Successfully signed up!".into(),
            }
            .encode(&mut buf)
            .unwrap();

            [vec![MessageType::SignupResponse as u8], buf].concat()
        }
        _ => unreachable!(),
    }
}