use rand::rngs::ThreadRng;
use rand::RngCore;

use std::sync::mpsc::*;
use std::thread::*;

use crate::params;
use crate::VecData;

enum Command {
    PreProc(usize),
    PreProcResp(Vec<u8>),
}

enum Response {
    PubParams(Vec<u8>),
    PreProcMsg(Vec<u8>),
}

pub struct Client {
    r: usize,
    thread_handle: JoinHandle<()>,
    incoming_cmd: SyncSender<Command>,
    outgoing_resp: Receiver<Response>,
}

impl Client {
    pub fn new(r: usize) -> (Self, Vec<u8>) {
        let (incoming_cmd, incoming_cmd_recv) = sync_channel(0);
        let (outgoing_resp_send, outgoing_resp) = sync_channel(0);
        let thread_handle = spawn(move || {
            let spiral_params = params::get_spiral_params(r);
            let mut clientrng = rand::thread_rng();
            let mut spiral_client = spiral_rs::client::Client::init(&spiral_params, &mut clientrng);

            // The first communication is the pub_params
            let pub_params = spiral_client.generate_keys().serialize();
            outgoing_resp_send
                .send(Response::PubParams(pub_params))
                .unwrap();

            // Wait for commands
            loop {
                println!("Client waiting");
                match incoming_cmd_recv.recv() {
                    Err(_) => break,
                    _ => panic!("Received something unexpected"),
                }
            }
            println!("Client ending");
        });
        let pub_params = match outgoing_resp.recv() {
            Ok(Response::PubParams(x)) => x,
            _ => panic!("Received something unexpected"),
        };

        (
            Client {
                r,
                thread_handle,
                incoming_cmd,
                outgoing_resp,
            },
            pub_params,
        )
    }
}

#[repr(C)]
pub struct ClientNewRet {
    client: *mut Client,
    pub_params: VecData,
}

#[no_mangle]
pub extern "C" fn spir_client_new(r: u8) -> ClientNewRet {
    let (client, pub_params) = Client::new(r as usize);
    let vecdata = VecData {
        data: pub_params.as_ptr(),
        len: pub_params.len(),
        cap: pub_params.capacity(),
    };
    std::mem::forget(pub_params);
    ClientNewRet {
        client: Box::into_raw(Box::new(client)),
        pub_params: vecdata,
    }
}

#[no_mangle]
pub extern "C" fn spir_client_free(client: *mut Client) {
    if client.is_null() {
        return;
    }
    unsafe {
        Box::from_raw(client);
    }
}