/***
    This file is part of snapcast
    Copyright (C) 2014-2019  Johannes Pohl

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
***/

#include "controlServer.h"
#include "aixlog.hpp"
#include "common/snapException.h"
#include "common/utils.h"
#include "config.h"
#include "jsonrpcpp.hpp"
#include "message/time.h"
#include <iostream>

using namespace std;

using json = nlohmann::json;


ControlServer::ControlServer(asio::io_context* io_context, size_t port, ControlMessageReceiver* controlMessageReceiver)
    : acceptor_v4_(nullptr), acceptor_v6_(nullptr), io_context_(io_context), port_(port), controlMessageReceiver_(controlMessageReceiver)
{
}


ControlServer::~ControlServer()
{
    //	stop();
}


void ControlServer::cleanup()
{
    std::lock_guard<std::recursive_mutex> mlock(session_mutex_);
    for (auto it = sessions_.begin(); it != sessions_.end();)
    {
        if (it->expired())
        {
            SLOG(ERROR) << "Session inactive. Removing\n";
            sessions_.erase(it++);
        }
        else
            ++it;
    }
}


void ControlServer::send(const std::string& message, const ControlSession* excludeSession)
{
    cleanup();
    for (auto s : sessions_)
    {
        if (auto session = s.lock())
        {
            if (session.get() != excludeSession)
                session->sendAsync(message);
        }
    }
}


void ControlServer::onMessageReceived(ControlSession* connection, const std::string& message)
{
    std::lock_guard<std::recursive_mutex> mlock(session_mutex_);
    LOG(DEBUG) << "received: \"" << message << "\"\n";
    // if ((message == "quit") || (message == "exit") || (message == "bye"))
    // {
    //     for (auto it = sessions_.begin(); it != sessions_.end(); ++it)
    //     {
    //         auto session = it->lock();
    //         if (!session)
    //             continue;
    //         if (session.get() == connection)
    //         {
    //             /// delete in a thread to avoid deadlock
    //             auto func = [&](std::shared_ptr<ControlSession> s) -> void { sessions_.erase(s); };
    //             std::thread t(func, *it);
    //             t.detach();
    //             break;
    //         }
    //     }
    // }
    // else
    // {
        if (controlMessageReceiver_ != nullptr)
            controlMessageReceiver_->onMessageReceived(connection, message);
    // }
}



void ControlServer::startAccept()
{
    if (acceptor_v4_)
    {
        socket_ptr socket_v4 = make_shared<tcp::socket>(*io_context_);
        acceptor_v4_->async_accept(*socket_v4, bind(&ControlServer::handleAccept, this, socket_v4));
    }
    if (acceptor_v6_)
    {
        socket_ptr socket_v6 = make_shared<tcp::socket>(*io_context_);
        acceptor_v6_->async_accept(*socket_v6, bind(&ControlServer::handleAccept, this, socket_v6));
    }
}


void ControlServer::handleAccept(socket_ptr socket)
{
    try
    {
        struct timeval tv;
        tv.tv_sec = 5;
        tv.tv_usec = 0;
        setsockopt(socket->native_handle(), SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv));
        setsockopt(socket->native_handle(), SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv));
        //	socket->set_option(boost::asio::ip::tcp::no_delay(false));
        SLOG(NOTICE) << "ControlServer::NewConnection: " << socket->remote_endpoint().address().to_string() << endl;
        shared_ptr<ControlSession> session = make_shared<ControlSession>(this, socket);
        {
            std::lock_guard<std::recursive_mutex> mlock(session_mutex_);
            session->start();
            sessions_.emplace_back(session);
            cleanup();
        }
    }
    catch (const std::exception& e)
    {
        SLOG(ERROR) << "Exception in ControlServer::handleAccept: " << e.what() << endl;
    }
    startAccept();
}


void ControlServer::start()
{
    bool is_v6_only(true);
    tcp::endpoint endpoint_v6(tcp::v6(), port_);
    try
    {
        acceptor_v6_ = make_shared<tcp::acceptor>(*io_context_, endpoint_v6);
        error_code ec;
        acceptor_v6_->set_option(asio::ip::v6_only(false), ec);
        asio::ip::v6_only option;
        acceptor_v6_->get_option(option);
        is_v6_only = option.value();
        LOG(DEBUG) << "IPv6 only: " << is_v6_only << "\n";
    }
    catch (const asio::system_error& e)
    {
        LOG(ERROR) << "error creating TCP acceptor: " << e.what() << ", code: " << e.code() << "\n";
    }

    if (!acceptor_v6_ || is_v6_only)
    {
        tcp::endpoint endpoint_v4(tcp::v4(), port_);
        try
        {
            acceptor_v4_ = make_shared<tcp::acceptor>(*io_context_, endpoint_v4);
        }
        catch (const asio::system_error& e)
        {
            LOG(ERROR) << "error creating TCP acceptor: " << e.what() << ", code: " << e.code() << "\n";
        }
    }

    startAccept();
}


void ControlServer::stop()
{
    if (acceptor_v4_)
    {
        acceptor_v4_->cancel();
        acceptor_v4_ = nullptr;
    }
    if (acceptor_v6_)
    {
        acceptor_v6_->cancel();
        acceptor_v6_ = nullptr;
    }
    std::lock_guard<std::recursive_mutex> mlock(session_mutex_);
    for (auto s : sessions_)
    {
        if (auto session = s.lock())
            session->stop();
    }
}