#include "sender_tcp.h"
#include "sender_utility.hpp"
#include "simple_mq.h"
#include "variable_defs.h"

#include <boost/asio/io_context.hpp>
#include <boost/asio/ip/tcp.hpp>
#include <boost/asio/post.hpp>
#include <boost/asio/write.hpp>

#include <spdlog/spdlog.h>

#include <deque>

using namespace boost::asio::ip;
using boost::asio::buffer;
using boost::asio::io_context;
using boost::asio::post;
using boost::asio::write;
using boost::system::error_code;

using namespace sender_impl;
using namespace simple_mq_singleton;

struct sender_tcp::impl {

    sender_tcp *q_this = nullptr;
    std::unique_ptr<tcp::acceptor> acceptor;
    std::unique_ptr<tcp::socket> socket;
    smart_buffer<uint8_t> out_buf;

    void close_connection() {
        if (socket == nullptr) return;
        // TODO: log client exit
//        if (socket->is_open()) {
//            auto remote_ep = socket->remote_endpoint();
//            SPDLOG_INFO("Client {}:{} left.",
//                        remote_ep.address().to_string(), remote_ep.port());
//        }
        socket = std::make_unique<tcp::socket>(*q_this->get_ctx());
        mq().update_variable(SENDER_CONNECTED, false);
    }

    void send_frame(frame_ptr_type &&frame) {
        if (!socket->is_open()) return;

        uint64_t packet_length = frame->length
                                 + sizeof(frame->frame_id);
        auto out_length = packet_length
                          + sizeof(packet_length);
        out_buf.create(out_length);

        // fill out buffer
        auto ptr = out_buf.ptr;
        ptr = write_binary_number(ptr, packet_length);
        ptr = write_binary_number(ptr, frame->frame_id);
        memcpy(ptr, frame->ptr, frame->length);

        error_code err;
        write(*socket, buffer(out_buf.ptr, out_buf.length), err); // TODO: change to async operation
        if (err) {
            SPDLOG_WARN("Error while sending frame: {}", err.to_string());
            close_connection();
            async_waiting_client();
        }

        q_this->log_frame_sent(frame->frame_id);
        SPDLOG_TRACE("Frame {} sent, length = {}",
                     frame->frame_id, frame->length);
    }

    void async_waiting_client() {
        acceptor->async_accept(*socket, [this](error_code err) {
            if (err) {
                SPDLOG_ERROR("Error while accepting client: {}", err.to_string());
                async_waiting_client();
            }
            assert(socket->is_open());
            q_this->request_idr_frame();
            mq().update_variable(SENDER_CONNECTED, true);

            auto remote_ep = socket->remote_endpoint();
            SPDLOG_INFO("New client from {}:{}.",
                        remote_ep.address().to_string(), remote_ep.port());
        });
    }

    static impl *create(uint16_t listen_port, sender_tcp *q_this) {
        auto ret = new impl;
        ret->q_this = q_this;
        auto listen_ep = tcp::endpoint{tcp::v4(), listen_port};
        ret->acceptor = std::make_unique<tcp::acceptor>(*q_this->get_ctx(), listen_ep);
        ret->socket = std::make_unique<tcp::socket>(*q_this->get_ctx());
        ret->async_waiting_client();
        return ret;
    }

};

sender_tcp::~sender_tcp() = default;

sender_tcp *sender_tcp::create(uint16_t listen_port) {
    auto ret = std::make_unique<sender_tcp>();
    auto pimpl = impl::create(listen_port, ret.get());
    if (pimpl == nullptr) return nullptr;
    ret->pimpl.reset(pimpl);
    return ret.release();
}

void sender_tcp::close_connection() {
    pimpl->close_connection();
}

void sender_tcp::handle_frame(frame_ptr_type &&frame) {
    pimpl->send_frame(std::move(frame));
}