#include <string>
#include <thread>
#include <iostream>
#include <mutex>
#include <enet/enet.h>
using namespace std;

std::mutex mtx;
void main()
{
    // initialize
    if(enet_initialize()) {
        cout << "fail init" << endl;
        return;
    }

    ENetAddress address;
    address.host = ENET_HOST_ANY;
    address.port = 9000;

    ENetHost* server;
    server = enet_host_create(&address,
                  32,
                  2,
                  0,
                  0);
    if(server == NULL) {
        cout << "fail create host" << endl;
        enet_deinitialize();
        return;
    }

    ENetEvent event;
    int event_status;

    while(1) {
        {
            // lock_guard<std::mutex> lock(mtx);
            event_status = enet_host_service(server, &event, 5000);
        }
        if(event_status >= 0) {
            if(event.type == ENET_EVENT_TYPE_CONNECT) { // client connected
                // ENetAddress remote = event.peer->address; // peer address
            } else if(event.type == ENET_EVENT_TYPE_RECEIVE) {    // recv data
                enet_packet_destroy(event.packet); // free

                // ----------- send ------------
                thread t(std::bind([&] (ENetHost* server, ENetPeer* peer)
                {
                    string data(2 * 1024, 'b'); // not ok
                    ENetPacket* packet1 = enet_packet_create(data.c_str(), data.length(), ENET_PACKET_FLAG_RELIABLE);
                    if(!packet1) {
                        cout << "create packet fail" << endl;
                        return;
                    }
                    {
                        lock_guard<std::mutex> lock(mtx);

                        if(enet_peer_send(peer, 0, packet1) < 0) {
                            cout << "send fail" << endl;
                            return;
                        }
                        enet_host_flush (server);
                    }
                }, server, event.peer));
                t.detach();

            } else if(event.type == ENET_EVENT_TYPE_DISCONNECT) {     // disconnect
                // cout << "peer disconnected" << endl;
            }
        }
    }

    enet_deinitialize();
}