#include "output_hls.h"
#include <mist/stream.h>
#include <unistd.h>

namespace Mist {
  bool OutHLS::isReadyForPlay() {
    if (myMeta.tracks.size()){
      if (myMeta.mainTrack().fragments.size() > 4){
        return true;
      }
    }
    return false;
  }

  std::string OutHLS::h264init(const std::string & initData){
    std::stringstream r;
    MP4::AVCC avccBox;
    avccBox.setPayload(initData);
    r << std::hex << std::setw(2) << std::setfill('0') << (int)initData[1] << std::dec;
    r << std::hex << std::setw(2) << std::setfill('0') << (int)initData[2] << std::dec;
    r << std::hex << std::setw(2) << std::setfill('0') << (int)initData[3] << std::dec;
    return r.str();
  }

  ///\brief Builds an index file for HTTP Live streaming.
  ///\return The index file for HTTP Live Streaming.
  std::string OutHLS::liveIndex(){
    std::stringstream result;
    result << "#EXTM3U\r\n";
    int audioId = -1;
    for (std::map<unsigned int,DTSC::Track>::iterator it = myMeta.tracks.begin(); it != myMeta.tracks.end(); it++){
      if (it->second.codec == "AAC" || it->second.codec == "MP3"){
        audioId = it->first;
        break;
      }
    }
    unsigned int vidTracks = 0;
    for (std::map<unsigned int,DTSC::Track>::iterator it = myMeta.tracks.begin(); it != myMeta.tracks.end(); it++){
      if (it->second.codec == "H264"){
        vidTracks++;
        int bWidth = it->second.bps;
        if (bWidth < 5){
          bWidth = 5;
        }
        if (audioId != -1){
          bWidth += myMeta.tracks[audioId].bps;
        }
        result << "#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=" << (bWidth * 8);
        result << ",RESOLUTION=" << it->second.width << "x" << it->second.height;
        if (it->second.fpks){
          result << ",FRAME-RATE=" << (float)it->second.fpks / 1000; 
        }
        if (it->second.codec == "H264"){
          result << ",CODECS=\"";
          if (it->second.codec == "H264"){
            result << "avc1." << h264init(it->second.init);
          }
          if (audioId != -1){
            if (myMeta.tracks[audioId].codec == "AAC"){
              result << ",mp4a.40.2";
            }else if (myMeta.tracks[audioId].codec == "MP3" ){
              result << ",mp4a.40.34";
            }
          }
          result << "\"";
        }
        result <<"\r\n";
        result << it->first;
        if (audioId != -1){
          result << "_" << audioId;
        }
        result << "/index.m3u8?sessId=" << getpid() << "\r\n";
      }
    }
    if (!vidTracks && audioId) {
      result << "#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=" << (myMeta.tracks[audioId].bps * 8);
      if (myMeta.tracks[audioId].codec == "AAC"){
        result << ",CODECS=\"mp4a.40.2\"";
      }else if (myMeta.tracks[audioId].codec == "MP3" ){
        result << ",CODECS=\"mp4a.40.34\"";
      }
      result << "\r\n";
      result << audioId << "/index.m3u8\r\n";
    }
    DEBUG_MSG(DLVL_HIGH, "Sending this index: %s", result.str().c_str());
    return result.str();
  }

  std::string OutHLS::liveIndex(int tid, std::string & sessId) {
    updateMeta();
    std::stringstream result;
    //parse single track
    uint32_t target_dur = (myMeta.tracks[tid].biggestFragment() / 1000) + 1;
    result << "#EXTM3U\r\n#EXT-X-VERSION:3\r\n#EXT-X-TARGETDURATION:" << target_dur << "\r\n";

    std::deque<std::string> lines;
    std::deque<uint16_t> durs;
    uint32_t total_dur = 0;
    for (std::deque<DTSC::Fragment>::iterator it = myMeta.tracks[tid].fragments.begin(); it != myMeta.tracks[tid].fragments.end(); it++) {
      long long int starttime = myMeta.tracks[tid].getKey(it->getNumber()).getTime();
      long long duration = it->getDuration();
      if (duration <= 0){
        duration = myMeta.tracks[tid].lastms - starttime;
      }
      char lineBuf[400];

      if (sessId.size()){
        snprintf(lineBuf, 400, "#EXTINF:%f,\r\n%lld_%lld.ts?sessId=%s\r\n", (double)duration/1000, starttime, starttime + duration, sessId.c_str());
      }else{
        snprintf(lineBuf, 400, "#EXTINF:%f,\r\n%lld_%lld.ts\r\n", (double)duration/1000, starttime, starttime + duration);
      }
      durs.push_back(duration);
      total_dur += duration;
      lines.push_back(lineBuf);
    }
    unsigned int skippedLines = 0;
    if (myMeta.live && lines.size()) {
      //only print the last segment when VoD
      lines.pop_back();
      total_dur -= durs.back();
      durs.pop_back();
      //skip the first two segments when live, unless that brings us under 4 target durations
      while ((total_dur-durs.front()) > (target_dur * 4000) && skippedLines < 2) {
        lines.pop_front();
        total_dur -= durs.front();
        durs.pop_front();
        ++skippedLines;
      }
    }
    
    result << "#EXT-X-MEDIA-SEQUENCE:" << myMeta.tracks[tid].missedFrags + skippedLines << "\r\n";
    
    while (lines.size()){
      result << lines.front();
      lines.pop_front();
    }
    if (!myMeta.live || total_dur == 0) {
      result << "#EXT-X-ENDLIST\r\n";
    }
    DEBUG_MSG(DLVL_HIGH, "Sending this index: %s", result.str().c_str());
    return result.str();
  } //liveIndex
  
  
  OutHLS::OutHLS(Socket::Connection & conn) : TSOutput(conn){
    realTime = 0;
    until=0xFFFFFFFFFFFFFFFFull;
  }
  
  OutHLS::~OutHLS() {}
  
  void OutHLS::init(Util::Config * cfg){
    HTTPOutput::init(cfg);
    capa["name"] = "HLS";
    capa["desc"] = "Enables HTTP protocol Apple-specific streaming (also known as HLS).";
    capa["url_rel"] = "/hls/$/index.m3u8";
    capa["url_prefix"] = "/hls/$/";
    capa["codecs"][0u][0u].append("H264");
    capa["codecs"][0u][1u].append("AAC");
    capa["codecs"][0u][1u].append("MP3");
    capa["methods"][0u]["handler"] = "http";
    capa["methods"][0u]["type"] = "html5/application/vnd.apple.mpegurl";
    capa["methods"][0u]["priority"] = 9ll;
    //MP3 only works on Edge/Apple
    capa["exceptions"]["codec:MP3"] = JSON::fromString("[[\"blacklist\"],[\"whitelist\",[\"iPad\",\"iPhone\",\"iPod\",\"MacIntel\",\"Edge\"]]]");
  }

  void OutHLS::onHTTP() {
    std::string method = H.method;
    std::string sessId = H.GetVar("sessId");
    
    if (H.url == "/crossdomain.xml"){
      H.Clean();
      H.SetHeader("Content-Type", "text/xml");
      H.SetHeader("Server", "MistServer/" PACKAGE_VERSION);
      H.setCORSHeaders();
      if(method == "OPTIONS" || method == "HEAD"){
        H.SendResponse("200", "OK", myConn);
        H.Clean();
        return;
      }
      H.SetBody("<?xml version=\"1.0\"?><!DOCTYPE cross-domain-policy SYSTEM \"http://www.adobe.com/xml/dtds/cross-domain-policy.dtd\"><cross-domain-policy><allow-access-from domain=\"*\" /><site-control permitted-cross-domain-policies=\"all\"/></cross-domain-policy>");
      H.SendResponse("200", "OK", myConn);
      H.Clean(); //clean for any possible next requests
      return;
    } //crossdomain.xml

    if (H.method == "OPTIONS") {
      H.Clean();
      H.SetHeader("Content-Type", "application/octet-stream");
      H.SetHeader("Cache-Control", "no-cache");
      H.setCORSHeaders();
      H.SetBody("");
      H.SendResponse("200", "OK", myConn);
      H.Clean();
      return;
    }
    
    if (H.url.find("hls") == std::string::npos){
      onFail();
      return;
    }
    

    appleCompat = (H.GetHeader("User-Agent").find("iPad") != std::string::npos) || (H.GetHeader("User-Agent").find("iPod") != std::string::npos)|| (H.GetHeader("User-Agent").find("iPhone") != std::string::npos);
    bool VLCworkaround = false;
    if (H.GetHeader("User-Agent").substr(0, 3) == "VLC"){
      std::string vlcver = H.GetHeader("User-Agent").substr(4);
      if (vlcver[0] == '0' || vlcver[0] == '1' || (vlcver[0] == '2' && vlcver[2] < '2')){
        DEBUG_MSG(DLVL_INFO, "Enabling VLC version < 2.2.0 bug workaround.");
        VLCworkaround = true;
      }
    }

    initialize();

    if (!keepGoing()){
      onFail();
      return;
    }

    if (H.url.find(".m3u") == std::string::npos){
      std::string tmpStr = H.getUrl().substr(5 + streamName.size());
      long long unsigned int from;
      if (sscanf(tmpStr.c_str(), "/%u_%u/%llu_%llu.ts", &vidTrack, &audTrack, &from, &until) != 4){
        if (sscanf(tmpStr.c_str(), "/%u/%llu_%llu.ts", &vidTrack, &from, &until) != 3){
          DEBUG_MSG(DLVL_MEDIUM, "Could not parse URL: %s", H.getUrl().c_str());
          H.Clean();
          H.setCORSHeaders();
          H.SetBody("The HLS URL wasn't understood - what did you want, exactly?\n");
          myConn.SendNow(H.BuildResponse("404", "URL mismatch"));
          H.Clean(); //clean for any possible next requests
          return;
        }else{
          selectedTracks.clear();
          selectedTracks.insert(vidTrack);
        }
      }else{
        selectedTracks.clear();
        selectedTracks.insert(vidTrack);
        selectedTracks.insert(audTrack);
      }
      for (std::map<unsigned int,DTSC::Track>::iterator it = myMeta.tracks.begin(); it != myMeta.tracks.end(); it++){
        if (it->second.codec == "ID3"){
          selectedTracks.insert(it->first);
        }
      }

      //Keep a reference to the main track
      //This is called vidTrack, even for audio-only streams
      DTSC::Track & Trk = myMeta.tracks[vidTrack];

      if (myMeta.live) {
        if (from < Trk.firstms){
          H.Clean();
          H.setCORSHeaders();
          H.SetBody("The requested fragment is no longer kept in memory on the server and cannot be served.\n");
          myConn.SendNow(H.BuildResponse("404", "Fragment out of range"));
          H.Clean(); //clean for any possible next requests
          WARN_MSG("Fragment @ %llu too old", from);
          return;
        }
      }

      H.SetHeader("Content-Type", "video/mp2t");
      H.setCORSHeaders();
      if(method == "OPTIONS" || method == "HEAD"){
        H.SendResponse("200", "OK", myConn);
        H.Clean();
        return;
      }

      H.StartResponse(H, myConn, VLCworkaround);
      //we assume whole fragments - but timestamps may be altered at will
      uint32_t fragIndice = Trk.timeToFragnum(from);
      contPAT = Trk.missedFrags + fragIndice; //PAT continuity counter
      contPMT = Trk.missedFrags + fragIndice; //PMT continuity counter
      contSDT = Trk.missedFrags + fragIndice; //SDT continuity counter
      packCounter = 0;
      parseData = true;
      wantRequest = false;
      seek(from);
      ts_from = from;
    } else {
      initialize();
      std::string request = H.url.substr(H.url.find("/", 5) + 1);
      H.Clean();
      H.SetHeader("Content-Type", "application/vnd.apple.mpegurl");
      H.SetHeader("Cache-Control", "no-cache");
      H.setCORSHeaders();
      if (!myMeta.tracks.size()){
        H.SendResponse("404", "Not online or found", myConn);
        H.Clean();
        return;
      }
      if(method == "OPTIONS" || method == "HEAD"){
        H.SendResponse("200", "OK", myConn);
        H.Clean();
        return;
      }
      std::string manifest;
      if (request.find("/") == std::string::npos){
        manifest = liveIndex();
      }else{
        int selectId = atoi(request.substr(0,request.find("/")).c_str());
        manifest = liveIndex(selectId, sessId);
      }
      H.SetBody(manifest);
      H.SendResponse("200", "OK", myConn);
    }
  }

  void OutHLS::sendNext(){
    //First check if we need to stop.
    if (thisPacket.getTime() >= until){
      stop();
      wantRequest = true;
      parseData = false;

      //Ensure alignment of contCounters for selected tracks, to prevent discontinuities.
      for (std::set<unsigned long>::iterator it = selectedTracks.begin(); it != selectedTracks.end(); ++it){
        DTSC::Track & Trk = myMeta.tracks[*it];
        uint32_t pkgPid = 255 + *it;
        int & contPkg = contCounters[pkgPid];
        if (contPkg % 16 != 0){
          packData.clear();
          packData.setPID(pkgPid);
          packData.addStuffing();
          while (contPkg % 16 != 0){
            packData.setContinuityCounter(++contPkg);
            sendTS(packData.checkAndGetBuffer());
          }
          packData.clear();
        }
      }

      //Signal end of data
      H.Chunkify("", 0, myConn);
      return;
    }
    //Invoke the generic TS output sendNext handler
    TSOutput::sendNext();
  }

  void OutHLS::sendTS(const char * tsData, unsigned int len){    
    H.Chunkify(tsData, len, myConn);
  }
}