/*
 * Copyright (c) 2016 The ZLMediaKit project authors. All Rights Reserved.
 *
 * This file is part of ZLMediaKit(https://github.com/xia-chu/ZLMediaKit).
 *
 * Use of this source code is governed by MIT 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.
 */

#include "RtmpSession.h"
#include "Common/config.h"
#include "Util/onceToken.h"

using namespace std;
using namespace toolkit;

namespace mediakit {

RtmpSession::RtmpSession(const Socket::Ptr &sock) : Session(sock) {
    GET_CONFIG(uint32_t,keep_alive_sec,Rtmp::kKeepAliveSecond);
    sock->setSendTimeOutSecond(keep_alive_sec);
}

RtmpSession::~RtmpSession() = default;

void RtmpSession::onError(const SockException& err) {
    bool is_player = !_push_src_ownership;
    uint64_t duration = _ticker.createdTime() / 1000;
    WarnP(this) << (is_player ? "RTMP播放器(" : "RTMP推流器(")
                << _media_info.shortUrl()
                << ")断开:" << err.what()
                << ",耗时(s):" << duration;

    //流量统计事件广播
    GET_CONFIG(uint32_t, iFlowThreshold, General::kFlowThreshold);

    if (_total_bytes >= iFlowThreshold * 1024) {
        NoticeCenter::Instance().emitEvent(Broadcast::kBroadcastFlowReport, _media_info, _total_bytes, duration, is_player, static_cast<SockInfo &>(*this));
    }

    //如果是主动关闭的，那么不延迟注销
    if (_push_src && _continue_push_ms && err.getErrCode() != Err_shutdown) {
        //取消所有权
        _push_src_ownership = nullptr;
        //延时10秒注销流
        auto push_src = std::move(_push_src);
        getPoller()->doDelayTask(_continue_push_ms, [push_src]() { return 0; });
    }
}

void RtmpSession::onManager() {
    GET_CONFIG(uint32_t, handshake_sec, Rtmp::kHandshakeSecond);
    GET_CONFIG(uint32_t, keep_alive_sec, Rtmp::kKeepAliveSecond);

    if (_ticker.createdTime() > handshake_sec * 1000) {
        if (!_ring_reader && !_push_src) {
            shutdown(SockException(Err_timeout, "illegal connection"));
        }
    }
    if (_push_src) {
        // push
        if (_ticker.elapsedTime() > keep_alive_sec * 1000) {
            shutdown(SockException(Err_timeout, "recv data from rtmp pusher timeout"));
        }
    }
}

void RtmpSession::onRecv(const Buffer::Ptr &buf) {
    _ticker.resetTime();
    _total_bytes += buf->size();
    onParseRtmp(buf->data(), buf->size());
}

void RtmpSession::onCmd_connect(AMFDecoder &dec) {
    auto params = dec.load<AMFValue>();
    ///////////set chunk size////////////////
    sendChunkSize(60000);
    ////////////window Acknowledgement size/////
    sendAcknowledgementSize(5000000);
    ///////////set peerBandwidth////////////////
    sendPeerBandwidth(5000000);

    auto tc_url = params["tcUrl"].as_string();
    if (tc_url.empty()) {
        // defaultVhost:默认vhost
        tc_url = string(RTMP_SCHEMA) + "://" + DEFAULT_VHOST + "/" + _media_info.app;
    } else {
        auto pos = tc_url.rfind('?');
        if (pos != string::npos) {
            // tc_url 中可能包含?以及参数，参见issue: #692
            tc_url = tc_url.substr(0, pos);
        }
    }
    // 初步解析，只用于获取vhost信息
    _media_info.parse(tc_url);
    _media_info.schema = RTMP_SCHEMA;
    // 赋值rtmp app
    _media_info.app = params["app"].as_string();

    bool ok = true; //(app == APP_NAME);
    AMFValue version(AMF_OBJECT);
    version.set("fmsVer", "FMS/3,0,1,123");
    version.set("capabilities", 31.0);
    AMFValue status(AMF_OBJECT);
    status.set("level", ok ? "status" : "error");
    status.set("code", ok ? "NetConnection.Connect.Success" : "NetConnection.Connect.InvalidApp");
    status.set("description", ok ? "Connection succeeded." : "InvalidApp.");
    status.set("objectEncoding", params["objectEncoding"]);
    sendReply(ok ? "_result" : "_error", version, status);
    if (!ok) {
        throw std::runtime_error("Unsupported application: " + _media_info.app);
    }

    AMFEncoder invoke;
    invoke << "onBWDone" << 0.0 << nullptr;
    sendResponse(MSG_CMD, invoke.data());
}

void RtmpSession::onCmd_createStream(AMFDecoder &dec) {
    sendReply("_result", nullptr, double(STREAM_MEDIA));
}

void RtmpSession::onCmd_publish(AMFDecoder &dec) {
    std::shared_ptr<Ticker> ticker(new Ticker);
    weak_ptr<RtmpSession> weak_self = static_pointer_cast<RtmpSession>(shared_from_this());
    std::shared_ptr<onceToken> token(new onceToken(nullptr, [ticker, weak_self]() {
        auto strong_self = weak_self.lock();
        if (strong_self) {
            DebugP(strong_self.get()) << "publish 回复时间:" << ticker->elapsedTime() << "ms";
        }
    }));
    dec.load<AMFValue>();/* NULL */
    // 赋值为rtmp stream id 信息
    _media_info.stream = getStreamId(dec.load<std::string>());
    // 再解析url，切割url为app/stream_id (不一定符合rtmp url切割规范)
    _media_info.parse(_media_info.getUrl());

    auto now_stream_index = _now_stream_index;
    auto on_res = [this, token, now_stream_index](const string &err, const ProtocolOption &option) {
        _now_stream_index = now_stream_index;
        if (!err.empty()) {
            sendStatus({ "level", "error",
                         "code", "NetStream.Publish.BadAuth",
                         "description", err,
                         "clientid", "0" });
            shutdown(SockException(Err_shutdown, StrPrinter << "Unauthorized:" << err));
            return;
        }

        assert(!_push_src);
        auto src = MediaSource::find(RTMP_SCHEMA, _media_info.vhost, _media_info.app, _media_info.stream);
        auto push_failed = (bool)src;

        while (src) {
            //尝试断连后继续推流
            auto rtmp_src = dynamic_pointer_cast<RtmpMediaSourceImp>(src);
            if (!rtmp_src) {
                //源不是rtmp推流产生的
                break;
            }
            auto ownership = rtmp_src->getOwnership();
            if (!ownership) {
                //获取推流源所有权失败
                break;
            }
            _push_src = std::move(rtmp_src);
            _push_src_ownership = std::move(ownership);
            push_failed = false;
            break;
        }

        if (push_failed) {
            sendStatus({"level", "error",
                        "code", "NetStream.Publish.BadName",
                        "description", "Already publishing.",
                        "clientid", "0" });
            shutdown(SockException(Err_shutdown, StrPrinter << "Already publishing:" << err));
            return;
        }

        if (!_push_src) {
            _push_src = std::make_shared<RtmpMediaSourceImp>(_media_info);
            //获取所有权
            _push_src_ownership = _push_src->getOwnership();
            _push_src->setProtocolOption(option);
        }

        _push_src->setListener(static_pointer_cast<RtmpSession>(shared_from_this()));
        _continue_push_ms = option.continue_push_ms;
        sendStatus({"level", "status",
                    "code", "NetStream.Publish.Start",
                    "description", "Started publishing stream.",
                    "clientid", "0" });

        setSocketFlags();
    };

    if(_media_info.app.empty() || _media_info.stream.empty()){
        //不允许莫名其妙的推流url
        on_res("rtmp推流url非法", ProtocolOption());
        return;
    }

    Broadcast::PublishAuthInvoker invoker = [weak_self, on_res, token](const string &err, const ProtocolOption &option) {
        auto strong_self = weak_self.lock();
        if (!strong_self) {
            return;
        }
        strong_self->async([weak_self, on_res, err, token, option]() {
            auto strong_self = weak_self.lock();
            if (!strong_self) {
                return;
            }
            on_res(err, option);
        });
    };
    auto flag = NoticeCenter::Instance().emitEvent(Broadcast::kBroadcastMediaPublish, MediaOriginType::rtmp_push, _media_info, invoker, static_cast<SockInfo &>(*this));
    if(!flag){
        //该事件无人监听，默认鉴权成功
        on_res("", ProtocolOption());
    }
}

void RtmpSession::onCmd_deleteStream(AMFDecoder &dec) {
    _push_src = nullptr;
    //此时回复可能触发broken pipe事件，从而直接触发onError回调；所以需要先把_push_src置空，防止触发断流续推功能
    sendStatus({ "level", "status",
                 "code", "NetStream.Unpublish.Success",
                 "description", "Stop publishing." });
    throw std::runtime_error(StrPrinter << "Stop publishing" << endl);
}

void RtmpSession::sendStatus(const std::initializer_list<string> &key_value) {
    AMFValue status(AMF_OBJECT);
    int i = 0;
    string key;
    for (auto &val : key_value) {
        if (++i % 2 == 0) {
            status.set(key, val);
        } else {
            key = val;
        }
    }
    sendReply("onStatus", nullptr, status);
}

void RtmpSession::sendPlayResponse(const string &err, const RtmpMediaSource::Ptr &src) {
    bool auth_success = err.empty();
    bool ok = (src.operator bool() && auth_success);
    if (ok) {
        //stream begin
        sendUserControl(CONTROL_STREAM_BEGIN, STREAM_MEDIA);
    }
    // onStatus(NetStream.Play.Reset)
    sendStatus({ "level", (ok ? "status" : "error"),
                 "code", (ok ? "NetStream.Play.Reset" : (auth_success ? "NetStream.Play.StreamNotFound" : "NetStream.Play.BadAuth")),
                 "description", (ok ? "Resetting and playing." : (auth_success ? "No such stream." : err.data())),
                 "details", _media_info.stream,
                 "clientid", "0" });

    if (!ok) {
        string err_msg = StrPrinter << (auth_success ? "no such stream:" : err.data()) << " " << _media_info.shortUrl();
        shutdown(SockException(Err_shutdown, err_msg));
        return;
    }

    // onStatus(NetStream.Play.Start)

    sendStatus({ "level", "status",
                 "code", "NetStream.Play.Start",
                 "description", "Started playing." ,
                 "details", _media_info.stream,
                 "clientid", "0"});

    // |RtmpSampleAccess(true, true)
    AMFEncoder invoke;
    invoke << "|RtmpSampleAccess" << true << true;
    sendResponse(MSG_DATA, invoke.data());

    //onStatus(NetStream.Data.Start)
    invoke.clear();
    AMFValue obj(AMF_OBJECT);
    obj.set("code", "NetStream.Data.Start");
    invoke << "onStatus" << obj;
    sendResponse(MSG_DATA, invoke.data());

    //onStatus(NetStream.Play.PublishNotify)
    sendStatus({ "level", "status",
                 "code", "NetStream.Play.PublishNotify",
                 "description", "Now published." ,
                 "details", _media_info.stream,
                 "clientid", "0"});

    auto &metadata = src->getMetaData();
    if(metadata){
        //在有metadata的情况下才发送metadata
        //其实metadata没什么用，有些推流器不产生metadata
        // onMetaData
        invoke.clear();
        invoke << "onMetaData" << metadata;
        sendResponse(MSG_DATA, invoke.data());
    }

    src->getConfigFrame([&](const RtmpPacket::Ptr &pkt) {
        onSendMedia(pkt);
    });

    src->pause(false);
    _ring_reader = src->getRing()->attach(getPoller());
    weak_ptr<RtmpSession> weak_self = static_pointer_cast<RtmpSession>(shared_from_this());
    _ring_reader->setGetInfoCB([weak_self]() { return weak_self.lock(); });
    _ring_reader->setReadCB([weak_self](const RtmpMediaSource::RingDataType &pkt) {
        auto strong_self = weak_self.lock();
        if (!strong_self) {
            return;
        }
        size_t i = 0;
        auto size = pkt->size();
        strong_self->setSendFlushFlag(false);
        pkt->for_each([&](const RtmpPacket::Ptr &rtmp){
            if(++i == size){
                strong_self->setSendFlushFlag(true);
            }
            strong_self->onSendMedia(rtmp);
        });
    });
    _ring_reader->setDetachCB([weak_self]() {
        auto strong_self = weak_self.lock();
        if (!strong_self) {
            return;
        }
        strong_self->shutdown(SockException(Err_shutdown,"rtmp ring buffer detached"));
    });
    src->pause(false);
    _play_src = src;
    //提高服务器发送性能
    setSocketFlags();
}

void RtmpSession::doPlayResponse(const string &err,const std::function<void(bool)> &cb){
    if(!err.empty()){
        //鉴权失败，直接返回播放失败
        sendPlayResponse(err, nullptr);
        cb(false);
        return;
    }

    //鉴权成功，查找媒体源并回复
    weak_ptr<RtmpSession> weak_self = static_pointer_cast<RtmpSession>(shared_from_this());
    MediaSource::findAsync(_media_info, weak_self.lock(), [weak_self,cb](const MediaSource::Ptr &src){
        auto rtmp_src = dynamic_pointer_cast<RtmpMediaSource>(src);
        auto strong_self = weak_self.lock();
        if(strong_self){
            strong_self->sendPlayResponse("", rtmp_src);
        }
        cb(rtmp_src.operator bool());
    });
}

void RtmpSession::doPlay(AMFDecoder &dec){
    std::shared_ptr<Ticker> ticker(new Ticker);
    weak_ptr<RtmpSession> weak_self = static_pointer_cast<RtmpSession>(shared_from_this());
    std::shared_ptr<onceToken> token(new onceToken(nullptr, [ticker,weak_self](){
        auto strong_self = weak_self.lock();
        if (strong_self) {
            DebugP(strong_self.get()) << "play 回复时间:" << ticker->elapsedTime() << "ms";
        }
    }));
    auto now_stream_index = _now_stream_index;
    Broadcast::AuthInvoker invoker = [weak_self, token, now_stream_index](const string &err) {
        auto strong_self = weak_self.lock();
        if (!strong_self) {
            return;
        }
        strong_self->async([weak_self, err, token, now_stream_index]() {
            auto strong_self = weak_self.lock();
            if (!strong_self) {
                return;
            }
            strong_self->_now_stream_index = now_stream_index;
            strong_self->doPlayResponse(err, [token](bool) {});
        });
    };

    auto flag = NoticeCenter::Instance().emitEvent(Broadcast::kBroadcastMediaPlayed, _media_info, invoker, static_cast<SockInfo &>(*this));
    if (!flag) {
        // 该事件无人监听,默认不鉴权
        doPlayResponse("", [token](bool) {});
    }
}

void RtmpSession::onCmd_play2(AMFDecoder &dec) {
    doPlay(dec);
}

string RtmpSession::getStreamId(const string &str){
    string stream_id;
    string params;
    auto pos = str.find('?');
    if (pos != string::npos) {
        //有url参数
        stream_id = str.substr(0, pos);
        //获取url参数
        params = str.substr(pos + 1);
    } else {
        //没有url参数
        stream_id = str;
    }

    pos = stream_id.find(":");
    if (pos != string::npos) {
        //vlc和ffplay在播放 rtmp://127.0.0.1/record/0.mp4时，
        //传过来的url会是rtmp://127.0.0.1/record/mp4:0,
        //我们在这里还原成0.mp4
        //实际使用时发现vlc，mpv等会传过来rtmp://127.0.0.1/record/mp4:0.mp4,这里做个判断
        auto ext = stream_id.substr(0, pos);
        stream_id = stream_id.substr(pos + 1);
        if (stream_id.find(ext) == string::npos) {
            stream_id = stream_id + "." + ext;
        }
    }

    if (params.empty()) {
        //没有url参数
        return stream_id;
    }

    //有url参数
    return stream_id + '?' + params;
}

void RtmpSession::onCmd_play(AMFDecoder &dec) {
    dec.load<AMFValue>(); /* NULL */
    // 赋值为rtmp stream id 信息
    _media_info.stream = getStreamId(dec.load<std::string>());
    // 再解析url，切割url为app/stream_id (不一定符合rtmp url切割规范)
    _media_info.parse(_media_info.getUrl());
    doPlay(dec);
}

void RtmpSession::onCmd_pause(AMFDecoder &dec) {
    dec.load<AMFValue>();/* NULL */
    bool paused = dec.load<bool>();
    TraceP(this) << paused;

    sendStatus({ "level", "status",
                 "code", (paused ? "NetStream.Pause.Notify" : "NetStream.Unpause.Notify"),
                 "description", (paused ? "Paused stream." : "Unpaused stream.")});

    //streamBegin
    sendUserControl(paused ? CONTROL_STREAM_EOF : CONTROL_STREAM_BEGIN, STREAM_MEDIA);
    auto strongSrc = _play_src.lock();
    if (strongSrc) {
        strongSrc->pause(paused);
    }
}

void RtmpSession::onCmd_playCtrl(AMFDecoder &dec) {
    dec.load<AMFValue>();
    auto ctrlObj = dec.load<AMFValue>();
    int ctrlType = ctrlObj["ctrlType"].as_integer();
    float speed = ctrlObj["speed"].as_number();

    sendStatus({ "level", "status",
                 "code", "NetStream.Speed.Notify",
                 "description", "Speeding"});

    //streamBegin
    sendUserControl(CONTROL_STREAM_EOF, STREAM_MEDIA);

    auto strong_src = _play_src.lock();
    if (strong_src) {
        strong_src->speed(speed);
    }
}

void RtmpSession::setMetaData(AMFDecoder &dec) {
    std::string type = dec.load<std::string>();
    if (type != "onMetaData") {
        throw std::runtime_error("can only set metadata");
    }
    _push_metadata = dec.load<AMFValue>();
}

void RtmpSession::onProcessCmd(AMFDecoder &dec) {
    typedef void (RtmpSession::*cmd_function)(AMFDecoder &dec);
    static unordered_map<string, cmd_function> s_cmd_functions;
    static onceToken token([]() {
        s_cmd_functions.emplace("connect", &RtmpSession::onCmd_connect);
        s_cmd_functions.emplace("createStream", &RtmpSession::onCmd_createStream);
        s_cmd_functions.emplace("publish", &RtmpSession::onCmd_publish);
        s_cmd_functions.emplace("deleteStream", &RtmpSession::onCmd_deleteStream);
        s_cmd_functions.emplace("play", &RtmpSession::onCmd_play);
        s_cmd_functions.emplace("play2", &RtmpSession::onCmd_play2);
        s_cmd_functions.emplace("seek", &RtmpSession::onCmd_seek);
        s_cmd_functions.emplace("pause", &RtmpSession::onCmd_pause);
        s_cmd_functions.emplace("onPlayCtrl", &RtmpSession::onCmd_playCtrl);
    });

    std::string method = dec.load<std::string>();
    auto it = s_cmd_functions.find(method);
    if (it == s_cmd_functions.end()) {
//		TraceP(this) << "can not support cmd:" << method;
        return;
    }
    _recv_req_id = dec.load<double>();
    auto fun = it->second;
    (this->*fun)(dec);
}

void RtmpSession::onRtmpChunk(RtmpPacket::Ptr packet) {
    auto &chunk_data = *packet;
    switch (chunk_data.type_id) {
    case MSG_CMD:
    case MSG_CMD3: {
        AMFDecoder dec(chunk_data.buffer, chunk_data.type_id == MSG_CMD3 ? 3 : 0);
        onProcessCmd(dec);
        break;
    }

    case MSG_DATA:
    case MSG_DATA3: {
        AMFDecoder dec(chunk_data.buffer, chunk_data.type_id == MSG_DATA3 ? 3 : 0);
        std::string type = dec.load<std::string>();
        if (type == "@setDataFrame") {
            setMetaData(dec);
        } else if (type == "onMetaData") {
            //兼容某些不规范的推流器
            _push_metadata = dec.load<AMFValue>();
        } else {
            TraceP(this) << "unknown notify:" << type;
        }
        break;
    }

    case MSG_AUDIO:
    case MSG_VIDEO: {
        if (!_push_src) {
            WarnL << "Not a rtmp push!";
            return;
        }

        if (!_set_meta_data) {
            _set_meta_data = true;
            _push_src->setMetaData(_push_metadata ? _push_metadata : TitleMeta().getMetadata());
        }
        _push_src->onWrite(std::move(packet));
        break;
    }

    default:
        WarnP(this) << "unhandled message:" << (int) chunk_data.type_id << hexdump(chunk_data.buffer.data(), chunk_data.buffer.size());
        break;
    }
}

void RtmpSession::onCmd_seek(AMFDecoder &dec) {
    dec.load<AMFValue>();/* NULL */
    sendStatus({ "level", "status",
                 "code", "NetStream.Seek.Notify",
                 "description", "Seeking."});

    auto milliSeconds = (uint32_t)(dec.load<AMFValue>().as_number());
    InfoP(this) << "rtmp seekTo(ms):" << milliSeconds;
    auto strong_src = _play_src.lock();
    if (strong_src) {
        strong_src->seekTo(milliSeconds);
    }
}

void RtmpSession::onSendMedia(const RtmpPacket::Ptr &pkt) {
    sendRtmp(pkt->type_id, pkt->stream_index, pkt, pkt->time_stamp, pkt->chunk_id);
}

bool RtmpSession::close(MediaSource &sender) {
    //此回调在其他线程触发
    string err = StrPrinter << "close media: " << sender.getUrl();
    safeShutdown(SockException(Err_shutdown, err));
    return true;
}

int RtmpSession::totalReaderCount(MediaSource &sender) {
    return _push_src ? _push_src->totalReaderCount() : sender.readerCount();
}

MediaOriginType RtmpSession::getOriginType(MediaSource &sender) const{
    return MediaOriginType::rtmp_push;
}

string RtmpSession::getOriginUrl(MediaSource &sender) const {
    return _media_info.full_url;
}

std::shared_ptr<SockInfo> RtmpSession::getOriginSock(MediaSource &sender) const {
    return const_cast<RtmpSession *>(this)->shared_from_this();
}

toolkit::EventPoller::Ptr RtmpSession::getOwnerPoller(MediaSource &sender) {
    return getPoller();
}

void RtmpSession::setSocketFlags(){
    GET_CONFIG(int, merge_write_ms, General::kMergeWriteMS);
    if (merge_write_ms > 0) {
        //推流模式下，关闭TCP_NODELAY会增加推流端的延时，但是服务器性能将提高
        SockUtil::setNoDelay(getSock()->rawFD(), false);
        //播放模式下，开启MSG_MORE会增加延时，但是能提高发送性能
        setSendFlags(SOCKET_DEFAULE_FLAGS | FLAG_MORE);
    }
}

void RtmpSession::dumpMetadata(const AMFValue &metadata) {
    if (metadata.type() != AMF_OBJECT && metadata.type() != AMF_ECMA_ARRAY) {
        WarnL << "invalid metadata type:" << metadata.type();
        return;
    }
    _StrPrinter printer;
    metadata.object_for_each([&](const string &key, const AMFValue &val) {
        printer << "\r\n" << key << "\t:" << val.to_string();
    });
    InfoL << _media_info.shortUrl() << (string) printer;
}
} /* namespace mediakit */