/*
 * Copyright (c) 2016-present The ZLMediaKit project authors. All Rights Reserved.
 *
 * This file is part of ZLMediaKit(https://github.com/ZLMediaKit/ZLMediaKit).
 *
 * Use of this source code is governed by MIT-like license that can be found in the
 * LICENSE file in the root of the source tree. All contributing project authors
 * may be found in the AUTHORS file in the root of the source tree.
 */

#if defined(ENABLE_RTPPROXY)
#include "RtpSender.h"
#include "RtpSession.h"
#include "Rtsp/RtspSession.h"
#include "Thread/WorkThreadPool.h"
#include "Util/uv_errno.h"
#include "RtpCache.h"
#include "Rtcp/RtcpContext.h"

using namespace std;
using namespace toolkit;

namespace mediakit{

RtpSender::RtpSender(EventPoller::Ptr poller) {
    _poller = poller ? std::move(poller) : EventPollerPool::Instance().getPoller();
    _socket_rtp = Socket::createSocket(_poller, false);
}

RtpSender::~RtpSender() {
    try {
        flush();
    } catch (std::exception &ex) {
        WarnL << "Exception occurred: " << ex.what();
    }
}

void RtpSender::startSend(const MediaSourceEvent::SendRtpArgs &args, const function<void(uint16_t local_port, const SockException &ex)> &cb){
    _args = args;
    if (!_interface) {
        // 重连时不重新创建对象  [AUTO-TRANSLATED:b788cd5d]
        // Do not recreate the object when reconnecting
        auto lam = [this](std::shared_ptr<List<Buffer::Ptr>> list) { onFlushRtpList(std::move(list)); };
        switch (args.data_type) {
            case MediaSourceEvent::SendRtpArgs::kRtpPS: _interface = std::make_shared<RtpCachePS>(lam, atoi(args.ssrc.data()), args.pt, true); break;
            case MediaSourceEvent::SendRtpArgs::kRtpTS: _interface = std::make_shared<RtpCachePS>(lam, atoi(args.ssrc.data()), args.pt, false); break;
            case MediaSourceEvent::SendRtpArgs::kRtpES: _interface = std::make_shared<RtpCacheRaw>(lam, atoi(args.ssrc.data()), args.pt, args.only_audio); break;
            default: CHECK(0, "invalid rtp type: " + to_string(args.data_type)); break;
        }
    }

    auto delay_ms = _args.close_delay_ms ? _args.close_delay_ms : 5000;
    weak_ptr<RtpSender> weak_self = shared_from_this();
    if (args.con_type == MediaSourceEvent::SendRtpArgs::kTcpPassive) {
        auto tcp_listener = Socket::createSocket(_poller, false);
        if (args.src_port) {
            // 指定端口  [AUTO-TRANSLATED:ed4ca3dd]
            // Specify the port
            if (!tcp_listener->listen(args.src_port)) {
                throw std::invalid_argument(StrPrinter << "open tcp passive server failed on port: " << args.src_port << ", err: " << get_uv_errmsg(true));
            }
        } else {
            auto pr = std::make_pair(tcp_listener, Socket::createSocket(_poller, false));
            // 从端口池获取随机端口  [AUTO-TRANSLATED:139ceb4f]
            // Get a random port from the port pool
            makeSockPair(pr, "::", true, false);
        }
        // 定时器持有tcp_listener，保证超时时间内保持监听  [AUTO-TRANSLATED:39df3f48]
        // The timer holds the tcp_listener to ensure listening within the timeout period
        auto delay_task = _poller->doDelayTask(delay_ms, [weak_self, tcp_listener]() mutable {
            // 防止循环引用  [AUTO-TRANSLATED:e2e9f9e7]
            // Prevent circular references
            tcp_listener = nullptr;
            if (auto strong_self = weak_self.lock()) {
                strong_self->onClose(SockException(Err_timeout, "wait tcp connection timeout"));
            }
            return 0;
        });
        tcp_listener->setOnAccept([weak_self, delay_task](Socket::Ptr &sock, std::shared_ptr<void> &complete) {
            auto strong_self = weak_self.lock();
            if (!strong_self) {
                return;
            }
            delay_task->cancel();
            strong_self->_socket_rtp = sock;
            strong_self->onConnect();
            InfoL << "accept tcp connection from: " << sock->get_peer_ip() << ":" << sock->get_peer_port();
        });
        InfoL << "start tcp passive server on: " << tcp_listener->get_local_port();
        cb(tcp_listener->get_local_port(), SockException());

    } else if (args.con_type == MediaSourceEvent::SendRtpArgs::kUdpPassive) {
        if (args.src_port) {
            // 指定端口  [AUTO-TRANSLATED:ed4ca3dd]
            // Specify the port
            if (!_socket_rtp->bindUdpSock(args.src_port, "::", true)) {
                throw std::invalid_argument(StrPrinter << "open udp passive server failed on port: " << args.src_port << ", err: " << get_uv_errmsg(true));
            }
        } else {
            auto pr = std::make_pair(_socket_rtp, Socket::createSocket(_poller, false));
            // 从端口池获取随机端口  [AUTO-TRANSLATED:139ceb4f]
            // Get a random port from the port pool
            makeSockPair(pr, "::", true, true);
        }
        auto delay_task = _poller->doDelayTask(delay_ms, [weak_self]() mutable {
            if (auto strong_self = weak_self.lock()) {
                // 关闭端口  [AUTO-TRANSLATED:3b3dff64]
                // Close the port
                strong_self->_socket_rtp->closeSock();
                strong_self->onClose(SockException(Err_timeout, "wait udp connection timeout"));
            }
            return 0;
        });
        _socket_rtp->setOnRead([weak_self, delay_task](const Buffer::Ptr &buf, struct sockaddr *addr, int addr_len) {
            auto strong_self = weak_self.lock();
            if (!strong_self) {
                return;
            }
            delay_task->cancel();
            strong_self->_socket_rtp->bindPeerAddr(addr, addr_len, true);
            // 异步执行onConnect，防止在OnRead回调中调用setOnRead  [AUTO-TRANSLATED:83881d7f]
            // Execute onConnect asynchronously to prevent calling setOnRead in the OnRead callback
            strong_self->_poller->async([strong_self]() { strong_self->onConnect(); }, false);
            InfoL << "accept udp connection from: " << strong_self->_socket_rtp->get_peer_ip() << ":" << strong_self->_socket_rtp->get_peer_port();
        });
        InfoL << "start udp passive server on: " << _socket_rtp->get_local_port();
        cb(_socket_rtp->get_local_port(), SockException());

    } else if (args.con_type == MediaSourceEvent::SendRtpArgs::kUdpActive) {
        auto poller = _poller;
        WorkThreadPool::Instance().getPoller()->async([cb, args, weak_self, poller]() {
            struct sockaddr_storage addr;
            // 切换线程目的是为了dns解析放在后台线程执行  [AUTO-TRANSLATED:1a09ba8a]
            // The purpose of switching threads is to perform DNS resolution in the background thread
            if (!SockUtil::getDomainIP(args.dst_url.data(), args.dst_port, addr, AF_INET, SOCK_DGRAM, IPPROTO_UDP)) {
                poller->async([args, cb]() {
                    // 切回自己的线程  [AUTO-TRANSLATED:b95746d6]
                    // Switch back to your own thread
                    cb(0, SockException(Err_dns, StrPrinter << "dns resolution failed: " << args.dst_url));
                });
                return;
            }

            // dns解析成功  [AUTO-TRANSLATED:e1b35821]
            // DNS resolution successful
            poller->async([args, addr, weak_self, cb]() {
                // 切回自己的线程  [AUTO-TRANSLATED:b95746d6]
                // Switch back to your own thread
                auto strong_self = weak_self.lock();
                if (!strong_self) {
                    return;
                }
                string ifr_ip = addr.ss_family == AF_INET ? "0.0.0.0" : "::";
                try {
                    if (args.src_port) {
                        // 指定端口  [AUTO-TRANSLATED:ed4ca3dd]
                        // Specify the port
                        if (!strong_self->_socket_rtp->bindUdpSock(args.src_port, ifr_ip, true)) {
                            throw std::invalid_argument(StrPrinter << "open udp active client failed on port: " << args.src_port << ", err: " << get_uv_errmsg(true));
                        }
                    } else {
                        auto pr = std::make_pair(strong_self->_socket_rtp, Socket::createSocket(strong_self->_poller, false));
                        // 从端口池获取随机端口  [AUTO-TRANSLATED:139ceb4f]
                        // Get a random port from the port pool
                        makeSockPair(pr, ifr_ip, true, true);
                    }
                } catch (std::exception &ex) {
                    cb(0, SockException(Err_other, ex.what()));
                    return;
                }
                strong_self->_socket_rtp->bindPeerAddr((struct sockaddr *)&addr, 0, true);
                strong_self->onConnect();
                cb(strong_self->_socket_rtp->get_local_port(), SockException());
            });
        });
        InfoL << "start udp active send rtp to: " << args.dst_url << ":" << args.dst_port;

    } else if (args.con_type == MediaSourceEvent::SendRtpArgs::kTcpActive) {
        _socket_rtp->connect(args.dst_url, args.dst_port,[cb, weak_self](const SockException &err) {
            auto strong_self = weak_self.lock();
            if (strong_self) {
                if (!err) {
                    // tcp连接成功  [AUTO-TRANSLATED:1a33669a]
                    // TCP connection successful
                    strong_self->onConnect();
                }
                cb(strong_self->_socket_rtp->get_local_port(), err);
            } else {
                cb(0, err);
            }
        }, delay_ms / 1000.0, "::", args.src_port);
        InfoL << "start tcp active send rtp to: " << args.dst_url << ":" << args.dst_port;
    } else {
        CHECK(0, "invalid con type");
    }
}

void RtpSender::createRtcpSocket() {
    if (_socket_rtcp) {
        return;
    }
    _socket_rtcp = Socket::createSocket(_socket_rtp->getPoller(), false);
    // rtcp端口使用户rtp端口+1  [AUTO-TRANSLATED:8a0a6b2c]
    // The RTCP port is the RTP port + 1
    if(!_socket_rtcp->bindUdpSock(_socket_rtp->get_local_port() + 1, _socket_rtp->get_local_ip(), true)){
        WarnL << "bind rtcp udp socket failed: " << get_uv_errmsg(true);
        _socket_rtcp = nullptr;
        return;
    }

    // 绑定目标rtcp端口(目标rtp端口 + 1)  [AUTO-TRANSLATED:c402de5b]
    // Bind the target RTCP port (target RTP port + 1)
    auto addr = SockUtil::make_sockaddr(_socket_rtp->get_peer_ip().data(), _socket_rtp->get_peer_port() + 1);
    _socket_rtcp->bindPeerAddr((struct sockaddr *)&addr, 0, true);

    _rtcp_context = std::make_shared<RtcpContextForSend>();
    weak_ptr<RtpSender> weak_self = shared_from_this();
    bool bind_addr = false;
    _socket_rtcp->setOnRead([weak_self, bind_addr](const Buffer::Ptr &buf, struct sockaddr *addr, int addr_len) mutable {
        // 接收receive report rtcp  [AUTO-TRANSLATED:38d3c1ba]
        // Receive receive report RTCP
        auto strong_self = weak_self.lock();
        if (!strong_self) {
            return;
        }
        if (!bind_addr) {
            // 收到对方rtcp打洞包后，再回复rtcp  [AUTO-TRANSLATED:393868ca]
            // Reply RTCP after receiving the other party's RTCP hole punching packet
            bind_addr = true;
            strong_self->_socket_rtcp->bindPeerAddr(addr, addr_len, true);
        }
        auto rtcp_arr = RtcpHeader::loadFromBytes(buf->data(), buf->size());
        for (auto &rtcp : rtcp_arr) {
            strong_self->onRecvRtcp(rtcp);
        }
    });
    InfoL << "open rtcp port success, start check rr rtcp timeout";
}

void RtpSender::onRecvRtcp(RtcpHeader *rtcp) {
    _rtcp_context->onRtcp(rtcp);
    _rtcp_recv_ticker.resetTime();
}

// 连接建立成功事件  [AUTO-TRANSLATED:ac279c86]
// Connection established successfully event
void RtpSender::onConnect() {
    _is_connect = true;
    // 加大发送缓存,防止udp丢包之类的问题  [AUTO-TRANSLATED:6e1cb40a]
    // Increase the send buffer to prevent problems such as UDP packet loss
    SockUtil::setSendBuf(_socket_rtp->rawFD(), 4 * 1024 * 1024);
    if (_args.con_type == MediaSourceEvent::SendRtpArgs::kTcpActive || _args.con_type == MediaSourceEvent::SendRtpArgs::kTcpPassive) {
        // 关闭tcp no_delay并开启MSG_MORE, 提高发送性能  [AUTO-TRANSLATED:c0f4e378]
        // Close TCP no_delay and enable MSG_MORE to improve sending performance
        SockUtil::setNoDelay(_socket_rtp->rawFD(), false);
        _socket_rtp->setSendFlags(SOCKET_DEFAULE_FLAGS | FLAG_MORE);
    } else if (_args.udp_rtcp_timeout) {
        createRtcpSocket();
    }
    // 连接建立成功事件  [AUTO-TRANSLATED:ac279c86]
    // Connection established successfully event
    weak_ptr<RtpSender> weak_self = shared_from_this();
    if (!_args.recv_stream_id.empty()) {
        mINI ini;
        ini[RtpSession::kStreamID] = _args.recv_stream_id;
        // 强制同步接收流和发送流的app和vhost  [AUTO-TRANSLATED:134c9663]
        // Force synchronization of the app and vhost of the receive stream and send stream
        ini[RtpSession::kApp] = _args.recv_stream_app;
        ini[RtpSession::kVhost] = _args.recv_stream_vhost;
        _rtp_session = std::make_shared<RtpSession>(_socket_rtp);
        _rtp_session->setParams(ini);

        _socket_rtp->setOnRead([weak_self](const Buffer::Ptr &buf, struct sockaddr *addr, int addr_len) {
            auto strong_self = weak_self.lock();
            if (!strong_self) {
                return;
            }
            try {
                strong_self->_rtp_session->onRecv(buf);
            } catch (std::exception &ex) {
                SockException err(toolkit::Err_shutdown, ex.what());
                strong_self->_rtp_session->shutdown(err);
            }
        });
    } else {
        _socket_rtp->setOnRead(nullptr);
    }
    _socket_rtp->setOnErr([weak_self](const SockException &err) {
        auto strong_self = weak_self.lock();
        if (strong_self) {
            strong_self->onErr(err);
        }
    });
    InfoL << "startSend rtp success: " << _socket_rtp->get_peer_ip() << ":" << _socket_rtp->get_peer_port() << ", data_type: " << _args.data_type << ", con_type: " << _args.con_type;
}

bool RtpSender::addTrack(const Track::Ptr &track) {
    if (_args.only_audio && track->getTrackType() == TrackVideo) {
        // 如果只发送音频则忽略视频  [AUTO-TRANSLATED:6843e322]
        // Ignore video if only audio is sent
        return false;
    }
    return _interface->addTrack(track);
}

void RtpSender::addTrackCompleted() {
    _interface->addTrackCompleted();
}

void RtpSender::resetTracks() {
    _interface->resetTracks();
}

void RtpSender::flush() {
    if (_interface) {
        _interface->flush();
    }
}

bool RtpSender::inputFrame(const Frame::Ptr &frame) {
    if (_args.only_audio && frame->getTrackType() == TrackVideo) {
        // 如果只发送音频则忽略视频  [AUTO-TRANSLATED:6843e322]
        // Ignore video if only audio is sent
        return false;
    }
    // 连接成功后才做实质操作(节省cpu资源)  [AUTO-TRANSLATED:666253b3]
    // Perform the actual operation after the connection is successful (save CPU resources)
    return _is_connect ? _interface->inputFrame(frame) : false;
}

void RtpSender::onSendRtpUdp(const toolkit::Buffer::Ptr &buf, bool check) {
    if (!_socket_rtcp) {
        return;
    }
    auto rtp = static_pointer_cast<RtpPacket>(buf);
    _rtcp_context->onRtp(rtp->getSeq(), rtp->getStamp(), rtp->ntp_stamp, 90000 /*not used*/, rtp->size());

    if (!check) {
        // 减少判断次数  [AUTO-TRANSLATED:0cfaddd8]
        // Reduce the number of judgments
        return;
    }
    // 每5秒发送一次rtcp  [AUTO-TRANSLATED:3c9bcb7b]
    // Send RTCP every 5 seconds
    if (_rtcp_send_ticker.elapsedTime() > _args.rtcp_send_interval_ms) {
        _rtcp_send_ticker.resetTime();
        // rtcp ssrc为rtp ssrc + 1  [AUTO-TRANSLATED:318fada3]
        // rtcp ssrc is rtp ssrc + 1
        auto sr = _rtcp_context->createRtcpSR(atoi(_args.ssrc.data()) + 1);
        // send sender report rtcp
        _socket_rtcp->send(sr);
    }

    if (_rtcp_recv_ticker.elapsedTime() > _args.rtcp_timeout_ms) {
        // 接收rr rtcp超时  [AUTO-TRANSLATED:a6ccd262]
        // Receive rr rtcp timeout
        WarnL << "recv rr rtcp timeout";
        _rtcp_recv_ticker.resetTime();
        onClose(SockException(Err_timeout, "recv rr rtcp timeout"));
    }
}

void RtpSender::onClose(const SockException &ex) {
    auto cb = _on_close;
    if (cb) {
        // 在下次循环时触发onClose，原因是防止遍历map时删除元素  [AUTO-TRANSLATED:2841df7f]
        // Trigger onClose in the next loop to prevent deleting elements while iterating through the map
        _poller->async([cb, ex]() { cb(ex); }, false);
    }
}

// 此函数在其他线程执行  [AUTO-TRANSLATED:3569a681]
// This function is executed in another thread
void RtpSender::onFlushRtpList(shared_ptr<List<Buffer::Ptr>> rtp_list) {
    if (!_is_connect) {
        // 连接成功后才能发送数据  [AUTO-TRANSLATED:14d00ad5]
        // Data can only be sent after the connection is successful
        return;
    }

    size_t i = 0;
    auto size = rtp_list->size();
    rtp_list->for_each([&](Buffer::Ptr &packet) {
        switch (_args.con_type) {
            case MediaSourceEvent::SendRtpArgs::kUdpActive:
            case MediaSourceEvent::SendRtpArgs::kUdpPassive: {
                onSendRtpUdp(packet, i == 0);
                // udp模式，rtp over tcp前4个字节可以忽略  [AUTO-TRANSLATED:5d648f4b]
                // UDP mode, the first 4 bytes of rtp over tcp can be ignored
                _socket_rtp->send(std::make_shared<BufferRtp>(std::move(packet), RtpPacket::kRtpTcpHeaderSize), nullptr, 0, ++i == size);
                break;
            }
            case MediaSourceEvent::SendRtpArgs::kTcpActive:
            case MediaSourceEvent::SendRtpArgs::kTcpPassive: {
                // tcp模式, rtp over tcp前2个字节可以忽略,只保留后续rtp长度的2个字节  [AUTO-TRANSLATED:a3bc338a]
                // TCP mode, the first 2 bytes of rtp over tcp can be ignored, only the subsequent 2 bytes of rtp length are retained
                _socket_rtp->send(std::make_shared<BufferRtp>(std::move(packet), 2), nullptr, 0, ++i == size);
                break;
            }
            default: CHECK(0);
        }
    });
}

void RtpSender::onErr(const SockException &ex) {
    _is_connect = false;
    WarnL << "send rtp connection lost: " << ex;
    onClose(ex);
}

void RtpSender::setOnClose(std::function<void(const toolkit::SockException &ex)> on_close) {
    _on_close = std::move(on_close);
}

} // namespace mediakit
#endif // defined(ENABLE_RTPPROXY)