/*                                                                  -*- c++ -*-
 * vdr-ttxtsubs - A plugin for the Linux Video Disk Recorder
 * Copyright (c) 2003 - 2008 Ragnar Sundblad <ragge@nada.kth.se>
 *
 * 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 2 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, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 */

#include "ttxtsubsdisplayer.h"
#include "ttxtsubsdisplay.h"
#include "utils.h"
#include "ttxtsubsglobals.h"
#include "ttxtaudio.h"
#include <vdr/channels.h>

// ----- class cTtxtSubsDisplayer -----

cTtxtSubsDisplayer::cTtxtSubsDisplayer(int textpage)
  :
  cThread("TtxtSubsDisplayer"),
  mDisp(new cTtxtSubsDisplay()),
  mGetMutex(),
  mGetCond(),
  mRingBuf(188000, true),
  mRun(0)
{
  mDisp->SetPage(textpage);

  mRun = 1;
  this->Start(); // start thread
}

cTtxtSubsDisplayer::~cTtxtSubsDisplayer(void)
{
  // stop thread
  mRun = false;
  mGetCond.Broadcast();
  this->Cancel(5);

  delete mDisp;
}

// handled messages in ring buffer - runs in a thread of its own
void cTtxtSubsDisplayer::Action(void)
{
  while(mRun) {
    cFrame *f;

    f = mRingBuf.Get();

    if(f) {
      mDisp->TtxtData(f->Data(), f->Pts());
      mRingBuf.Drop(f);
    } else {
      // wait for more data
      mGetMutex.Lock();
      mGetCond.TimedWait(mGetMutex, 500);
      mDisp->TtxtData(NULL); // give display some idle time
      mGetMutex.Unlock();
    }
  }
}

void cTtxtSubsDisplayer::ShowDisplay(void)
{
  mDisp->Show();
}

void cTtxtSubsDisplayer::HideDisplay(void)
{
  mDisp->Hide();
}

// ----- class cTtxtSubsPlayer -----

cTtxtSubsPlayer::cTtxtSubsPlayer(int backup_textpage)
  :
  cTtxtSubsDisplayer(backup_textpage),
  mHasFilteredStream(0),
  mFoundLangPage(0),
  mLangChoise(1000),
  mLangInfoState(0)
{
  SetDescription("ttxtsubs player");
}

// Take PES packets and break out the teletext data
// Buffer the data for processing in a separate thread
// XXX We should do some filtering here to avoid unnecessary load!
void cTtxtSubsPlayer::PES_data(uchar *p, int Length, bool IsPesRecording, const struct tTeletextSubtitlePage teletextSubtitlePages[], int pageCount)
{
  int i;
  int64_t pts = 0;

  //printf("cTtxtSubsPlayer: len: %d\n", Length); // XXX

  if(Length < 46 || p[0] != 0 || p[1] != 0 || p[2] != 1 || p[3] != 0xbd || p[8] != 0x24 ||
     p[45] < 0x10 || p[45] >= 0x20) {
    fprintf(stderr, "cTtxtSubsPlayer::PES_data: bad indata!\n");
  }

  if (!mFoundLangPage)
  {
    if (teletextSubtitlePages && teletextSubtitlePages[0].ttxtType)
    {
      for (int p=0; p < pageCount; p++) {
        // isyslog("ttxtsubs: got page info from vdr: %s 0x%02X 0x%2X.0x%02X", teletextSubtitlePages[p].ttxtLanguage, teletextSubtitlePages[p].ttxtType,
        //   teletextSubtitlePages[p].ttxtMagazine, teletextSubtitlePages[p].ttxtPage);
        SetPreferredPage(teletextSubtitlePages[p].ttxtLanguage, teletextSubtitlePages[p].ttxtType == 0x05,
          (teletextSubtitlePages[p].ttxtMagazine << 8) + teletextSubtitlePages[p].ttxtPage);
      }
    }
  }

  // Recorded teletext typically has payload type 0x10.
  // We use the payload type 0x1f to indicate that we have our own
  // filtered stream, if we find that we only use that.

  if(p[45] == 0x1f && !mHasFilteredStream)
    mHasFilteredStream = 1;

  if(mHasFilteredStream && p[45] != 0x1f)
    return; // other teletext data, ignore

  if(mHasFilteredStream && !mFoundLangPage)
    SearchLanguagePage(p, Length);

  if (PesHasPts(p))
    pts = PesGetPts(p);

  //Some streams are missing the Subtitle pts so we use the audio instead
  if (!pts && cTtxtAudio::pts)
     pts = cTtxtAudio::pts;

  // payload_unit_start_indicator
  for(i = 1; (i*46) < Length ; i++) {
    if(0xff == p[i*46]) // stuffing data
      continue;

    cFrame *f = new cFrame(p + i*46, 46, ftUnknown, -1, pts);
    if (mRingBuf.Put(f))
    {
        mGetCond.Broadcast();
    }
    else
    {
        isyslog("ttxtsubs: buffer overflow!");
    }
  }
}

static void copy_inv_strip_par(uint8_t *dest, uint8_t *src, size_t len)
{
  size_t i;
  for(i = 0; i < len; i++)
    dest[i] = invtab[src[i]] & 0x7f;
}

void cTtxtSubsPlayer::SearchLanguagePage(uint8_t *p, int len)
{
  const char *infoline = "Subtitles Index Page";
  int foundlines = 0;

  if(len < (3*46))
     return;

  struct ttxt_data_field *d;
  for(d = ((struct ttxt_data_field *) p) + 1; ((uint8_t *) d) < (p + len + 45); d++) {
    int mp = UNHAM_INV(d->mag_addr_ham[0], d->mag_addr_ham[1]);
    //int mag = mp & 0x7;
    int packet = (mp >> 3) & 0x1f;
    uint8_t buf[40];

    if(d->data_unit_id != 0x02)
      break; // a subtitle line

    switch(foundlines) {
    case 0:
      if(packet != 0) // need a Y0 first
        return;
      foundlines++;
      break;
    case 1:
      if(packet != 1) // need a Y1
        return;
      copy_inv_strip_par(buf, d->data, sizeof(buf));
      if(memcmp((char *) buf, infoline, strlen(infoline)))
        return;
      foundlines++;
      break;
    case 2:
      mLangInfoState++;
      if(packet < 2) // need a Y2 or more
        return;
      if(mLangInfoState == 3)
        fprintf(stderr, "ttxtsubs: Chosen Language not found in recording, available languages:\n");
      copy_inv_strip_par(buf, d->data, sizeof(buf));
      for(size_t i = 0; i < 40; i += 8) {
        if(mLangInfoState == 3 && buf[i] >= 'a' && buf[i] <= 'z')
          fprintf(stderr, "          %c%c%c: %c%c%c %s\n", buf[i+4], buf[i+5], buf[i+6],
                  buf[i], buf[i+1], buf[i+2], buf[i+3] == ' ' ? "" :
                  buf[i+3] == 'h' ? "(Hearing Impaired)" : "(Unknown type)");

        if(buf[i] >= 'a' && buf[i] <= 'z' &&
           buf[i+1] >= 'a' && buf[i+1] <= 'z' &&
           buf[i+2] >= 'a' && buf[i+2] <= 'z' &&
           ((buf[i+3] == ' ') || (buf[i+3] == 'h')) &&
           buf[i+4] >= '1' && buf[i+4] <= '8' && 
           buf[i+5] >= '0' && buf[i+5] <= '9' && 
           buf[i+6] >= '0' && buf[i+6] <= '9' && 
           buf[i+7] == ' ') {
              unsigned int page =
                ((buf[i+4] - '0') << 8) +
                ((buf[i+5] - '0') << 4) +
                (buf[i+6] - '0');
              if(page >= 0x100 && page < 0x900) {
                if(page >= 0x800)
                  page -= 0x800;
                SetPreferredPage((char *)buf+i, buf[i+3] == 'h', page);
              }
        }
      }
      break;
    }
  }
}

bool cTtxtSubsPlayer::SetPreferredPage(const char* language, bool hearingImpaired, unsigned int bcdPage)
{
  // Some French channels still send wrong subtitle page number!
  // This is a hard fix to change the page numbers 05x to 08x
  // According to ETSI tables pages 850-859 are not used for
  // teletext subtitles in any country, so we assume, that these can
  // safely be mapped to 880-889

  if(bcdPage >= 0x50 && bcdPage <= 0x59)
     bcdPage += 0x30;

  int ch = globals.langChoise(language, hearingImpaired);
  if (ch >= 0 && ch < mLangChoise) {
    mLangChoise = ch;
    mDisp->SetPage(bcdPage);
    mFoundLangPage = 1;
    isyslog("Found subtitle page: %03x\n", bcdPage < 0x100 ? 0x800 + bcdPage : bcdPage);
  }
}