/*
 * H.264 Plugin codec for OpenH323/OPAL
 *
 * Copyright (C) 2007 Matthias Schneider, All Rights Reserved
 *
 * 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 St, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 */

#include "plugin-config.h"

#include "enc-ctx.h"
#include "rtpframe.h"

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#if defined(_WIN32) || defined(_WIN32_WCE)
  #include <malloc.h>
  #define STRCMPI  _strcmpi
#else
  #include <semaphore.h>
  #define STRCMPI  strcasecmp
#endif
#include <string.h>

#ifndef X264_LINK_STATIC
X264Library X264Lib;
#endif

static void logCallbackX264 (void * /*priv*/, int level, const char *fmt, va_list arg) {
  char buffer[512];
  int severity = 0;
  switch (level) {
    case X264_LOG_NONE:    severity = 1; break;
    case X264_LOG_ERROR:   severity = 1; break;
    case X264_LOG_WARNING: severity = 3; break;
    case X264_LOG_INFO:    severity = 4; break;
    case X264_LOG_DEBUG:   severity = 4; break;
    default:               severity = 4; break;
  }
  vsprintf(buffer, fmt, arg);
  if (strlen(buffer) > 0)
    buffer[strlen(buffer)-1] = 0;
  PTRACE(severity, "x264", buffer);
}

X264EncoderContext::X264EncoderContext()
{
  _frameCounter=0;
  _PFramesSinceLastIFrame = 0;

  _txH264Frame = new H264Frame();
  _txH264Frame->SetMaxPayloadSize(H264_PAYLOAD_SIZE);

  _inputFrame.i_type = X264_TYPE_AUTO;
  _inputFrame.i_qpplus1 = 0;
  _inputFrame.img.i_csp = X264_CSP_I420;
 
   X264_PARAM_DEFAULT(&_context);

  // Default
  // ABR with bit rate tolerance = 1 is CBR...
  _context.rc.i_rc_method = X264_RC_ABR;
  _context.rc.f_rate_tolerance = 1;

  // No aspect ratio correction
  _context.vui.i_sar_width = 0;
  _context.vui.i_sar_height = 0;

  // Enable logging
  _context.pf_log = logCallbackX264;
  _context.i_log_level = X264_LOG_DEBUG;
  _context.p_log_private = NULL;

  // Auto detect number of CPUs
  _context.i_threads = 0;  

  SetFrameWidth       (CIF_WIDTH);
  SetFrameHeight      (CIF_HEIGHT);
  SetFrameRate        (H264_FRAME_RATE);
  SetTargetBitrate    ((unsigned)(H264_BITRATE / 1000));
  SetProfileLevel     (H264_PROFILE_LEVEL);
  SetTSTO             (H264_TSTO);
  SetMaxKeyFramePeriod(H264_KEY_FRAME_INTERVAL);

  //_context.i_maxframes = 0;
  //_context.rc.b_stat_write = 0;
  //_context.analyse.inter = 0;
  _context.analyse.b_psnr = 0;

  _codec = X264_ENCODER_OPEN(&_context);
  
  if (_codec == NULL) {
    PTRACE(1, "x264", "Encoder\tCouldn't init x264 encoder");
  } 
  else
  {
    PTRACE(4, "x264", "Encoder\tx264 encoder successfully opened");
  }
}

X264EncoderContext::~X264EncoderContext()
{
    if (_codec != NULL)
    {
      X264_ENCODER_CLOSE(_codec);
      PTRACE(4, "x264", "Encoder\tClosed H.264 encoder, encoded " << _frameCounter << " Frames" );
    }
  if (_txH264Frame) delete _txH264Frame;
}

void X264EncoderContext::SetMaxRTPFrameSize(unsigned size)
{
  _txH264Frame->SetMaxPayloadSize(size);
}

void X264EncoderContext::SetMaxKeyFramePeriod (unsigned period)
{
  _IFrameInterval = _context.i_keyint_max = period;
  _PFramesSinceLastIFrame = _IFrameInterval + 1; // force a keyframe on the first frame
}

void X264EncoderContext::SetTargetBitrate(unsigned rate)
{
  _context.rc.i_vbv_max_bitrate = rate;
  _context.rc.i_bitrate = rate;
}

void X264EncoderContext::SetFrameWidth(unsigned width)
{
  _context.i_width = width;
}

void X264EncoderContext::SetFrameHeight(unsigned height)
{
  _context.i_height = height;
}

void X264EncoderContext::SetFrameRate(unsigned rate)
{
  _context.i_fps_num = (int)((rate + .5) * 1000);
  _context.i_fps_den = 1000;
}

void X264EncoderContext::SetTSTO (unsigned tsto)
{
    _context.rc.i_qp_min = H264_MIN_QUANT;
    _context.rc.i_qp_max = round ( (double)(51 - H264_MIN_QUANT) / 31 * tsto + H264_MIN_QUANT);
    _context.rc.i_qp_step = 4;	    
}

void X264EncoderContext::SetProfileLevel (unsigned profileLevel)
{
//  unsigned profile = (profileLevel & 0xff0000) >> 16;
//  bool constraint0 = (profileLevel & 0x008000) ? true : false;
//  bool constraint1 = (profileLevel & 0x004000) ? true : false;
//  bool constraint2 = (profileLevel & 0x002000) ? true : false;
//  bool constraint3 = (profileLevel & 0x001000) ? true : false;
  unsigned level   = (profileLevel & 0x0000ff);

  int i = 0;
  while (h264_levels[i].level_idc) {
    if (h264_levels[i].level_idc == level)
      break;
   i++; 
  }

  if (!h264_levels[i].level_idc) {
    PTRACE(1, "x264", "Illegal Level negotiated");
    return;
  }

  // We make use of the baseline profile, that means:
  // no B-Frames (too much latency in interactive video)
  // CBR (we want to get the max. quality making use of all the bitrate that is available)
  // baseline profile begin
  _context.b_cabac = 0;  // Only >= MAIN LEVEL
  _context.i_bframe = 0; // Only >= MAIN LEVEL

  // Level:
  _context.i_level_idc = level;
  
  // DPB from Level by default
  _context.rc.i_vbv_buffer_size = h264_levels[i].cpb;
  // MV Range from Level by default  
}

void X264EncoderContext::ApplyOptions()
{
  X264_ENCODER_CLOSE(_codec);
  _codec = X264_ENCODER_OPEN(&_context);
  if (_codec == NULL) {
    PTRACE(1, "x264", "Encoder\tCouldn't init x264 encoder");
  } 
  else
  {
    PTRACE(4, "x264", "Encoder\tx264 encoder successfully opened");
  }
}

int X264EncoderContext::EncodeFrames(const unsigned char * src, unsigned & srcLen, unsigned char * dst, unsigned & dstLen, unsigned int & flags)
{
  // create RTP frame from source buffer
  RTPFrame srcRTP(src, srcLen);

  // create RTP frame from destination buffer
  RTPFrame dstRTP(dst, dstLen);

  dstLen = 0;

  // from here, we are encoding a new frame
  if ((!_codec) || (!_txH264Frame))
  {
    return 0;
  }

  // if there are RTP packets to return, return them
  if  (_txH264Frame->HasRTPFrames())
  {
    _txH264Frame->GetRTPFrame(dstRTP, flags);
    dstLen = dstRTP.GetFrameLen();
    return 1;
  }

  if (srcRTP.GetPayloadSize() < sizeof(frameHeader))
  {
    PTRACE(1, "x264", "Encoder\tVideo grab too small, Close down video transmission thread");
    return 0;
  }

  frameHeader * header = (frameHeader *)srcRTP.GetPayloadPtr();
  if (header->x != 0 || header->y != 0)
  {
    PTRACE(1, "x264", "Encoder\tVideo grab of partial frame unsupported, Close down video transmission thread");
    return 0;
  }

  // do a validation of size
  // if the incoming data has changed size, tell the encoder
  if ((unsigned)_context.i_width != header->width || (unsigned)_context.i_height != header->height)
  {
    X264_ENCODER_CLOSE(_codec);
    _context.i_width = header->width;
    _context.i_height = header->height;
    _codec = X264_ENCODER_OPEN(&_context);
  } 

  bool wantIFrame = false;
  x264_nal_t* NALs;
  int numberOfNALs = 0;
  x264_picture_t dummyOutput;

  // Check whether to insert a keyframe 
  // (On the first frame and every_IFrameInterval)
  _PFramesSinceLastIFrame++;
  if (_PFramesSinceLastIFrame >= _IFrameInterval)
  {
    wantIFrame = true;
    _PFramesSinceLastIFrame = 0;
  }
  // Prepare the frame to be encoded
  _inputFrame.img.plane[0] = (uint8_t *)(((unsigned char *)header) + sizeof(frameHeader));
  _inputFrame.img.i_stride[0] = header->width;
  _inputFrame.img.plane[1] = (uint8_t *)((((unsigned char *)header) + sizeof(frameHeader)) 
                           + (int)(_inputFrame.img.i_stride[0]*header->height));
  _inputFrame.img.i_stride[1] = 
  _inputFrame.img.i_stride[2] = (int) ( header->width / 2 );
  _inputFrame.img.plane[2] = (uint8_t *)(_inputFrame.img.plane[1] + (int)(_inputFrame.img.i_stride[1] *header->height/2));
  _inputFrame.i_type = (wantIFrame || (flags && forceIFrame)) ? X264_TYPE_IDR : X264_TYPE_AUTO;

  while (numberOfNALs==0) { // workaround for first 2 packets being 0
    if (X264_ENCODER_ENCODE(_codec, &NALs, &numberOfNALs, &_inputFrame, &dummyOutput) < 0) {
      PTRACE(1,"x264", "Encoder\tEncoding failed");
      return 0;
    } 
  }
  
  _txH264Frame->BeginNewFrame();
  _txH264Frame->SetFromFrame(NALs, numberOfNALs);
  _txH264Frame->SetTimestamp(srcRTP.GetTimestamp());
  _frameCounter++; 

  if (_txH264Frame->HasRTPFrames())
  {
    _txH264Frame->GetRTPFrame(dstRTP, flags);
    dstLen = dstRTP.GetFrameLen();
    return 1;
  }
  return 1;
}
