/* GStreamer
 *  Copyright (C) 2022 Intel Corporation
 *     Author: He Junyan <junyan.he@intel.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the0
 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "gstvp9bitwriter.h"
#include <gst/base/gstbitwriter.h>

#define WRITE_BITS_UNCHECK(bw, val, nbits)                                    \
  (nbits <= 8 ? gst_bit_writer_put_bits_uint8 (bw, val, nbits) :              \
   (nbits <= 16 ? gst_bit_writer_put_bits_uint16 (bw, val, nbits) :           \
    (nbits <= 32 ? gst_bit_writer_put_bits_uint32 (bw, val, nbits) :          \
     FALSE)))

#define WRITE_BITS(bw, val, nbits)                                            \
  if (!WRITE_BITS_UNCHECK (bw, val, nbits)) {                                 \
    g_warning ("Unsupported bit size: %u", nbits);                            \
    have_space = FALSE;                                                       \
    goto error;                                                               \
  }

/**
 * gst_vp9_bit_writer_frame_header:
 * @frame_hdr: the frame header of #GstVp9FrameHdr to write
 * @data: (out caller-allocates)(not nullable): the stream
 *  generated by the frame header
 * @size: (inout): the size in bytes of the input and output
 *
 * Generating the according VP9 bit stream by providing the frame header.
 *
 * Returns: a #GstVp9BitWriterResult
 *
 * Since: 1.24
 **/
GstVp9BitWriterResult
gst_vp9_bit_writer_frame_header (const GstVp9FrameHdr * frame_hdr,
    guint8 * data, guint * size)
{
  gboolean have_space = TRUE;
  GstBitWriter bw;

  g_return_val_if_fail (frame_hdr != NULL, GST_VP9_BIT_WRITER_ERROR);
  g_return_val_if_fail (data != NULL, GST_VP9_BIT_WRITER_ERROR);
  g_return_val_if_fail (size != NULL, GST_VP9_BIT_WRITER_ERROR);
  g_return_val_if_fail (*size > 0, GST_VP9_BIT_WRITER_ERROR);

  gst_bit_writer_init_with_data (&bw, data, *size, FALSE);

  WRITE_BITS (&bw, GST_VP9_FRAME_MARKER, 2);
  /* profile_low_bit */
  WRITE_BITS (&bw, frame_hdr->profile & 0x01, 1);
  /* profile_high_bit */
  WRITE_BITS (&bw, (frame_hdr->profile & 0x02) >> 1, 1);
  if (frame_hdr->profile == 3)
    WRITE_BITS (&bw, 0, 1);

  if (frame_hdr->show_existing_frame) {
    WRITE_BITS (&bw, frame_hdr->show_existing_frame, 1);
    WRITE_BITS (&bw, frame_hdr->frame_to_show, 3);
    gst_bit_writer_align_bytes (&bw, 0);
  } else {
    GST_WARNING ("Frame header writing is not implemented.");
    goto error;
  }

  g_assert (gst_bit_writer_get_size (&bw) % 8 == 0);
  *size = gst_bit_writer_get_size (&bw) / 8;

  gst_bit_writer_reset (&bw);

  return GST_VP9_BIT_WRITER_OK;

error:
  gst_bit_writer_reset (&bw);
  *size = 0;
  return have_space ? GST_VP9_BIT_WRITER_INVALID_DATA :
      GST_VP9_BIT_WRITER_NO_MORE_SPACE;
}

/**
 * gst_vp9_bit_writer_superframe_info:
 * @frame_num: the frame number to composite this super frame
 * @frame_size: the size of each frame
 * @data: (inout): the stream data of this super frame
 * @size: (inout): the size in bytes of the input and output
 *
 * Appending the super frame info at the end of this stream.
 * Note: the input @data should already contain all frames' data in
 * the same order of @frame_size.
 *
 * Returns: a #GstVp9BitWriterResult
 *
 * Since: 1.24
 **/
GstVp9BitWriterResult
gst_vp9_bit_writer_superframe_info (guint frame_num, const gint * frame_size,
    guint8 * data, guint * size)
{
  GstBitWriter bw;
  GstVp9BitWriterResult ret = GST_VP9_BIT_WRITER_OK;
  guint data_sz = 0;
  guint i, j;

  g_return_val_if_fail (frame_num <= GST_VP9_MAX_FRAMES_IN_SUPERFRAME,
      GST_VP9_BIT_WRITER_ERROR);
  g_return_val_if_fail (frame_size != NULL, GST_VP9_BIT_WRITER_ERROR);
  g_return_val_if_fail (data != NULL, GST_VP9_BIT_WRITER_ERROR);
  g_return_val_if_fail (size != NULL, GST_VP9_BIT_WRITER_ERROR);

  for (i = 0; i < frame_num; i++)
    data_sz += frame_size[i];

  if (*size < data_sz + 1 /* superframe_header */  +
      4 * frame_num /* superframe_index */  + 1 /* superframe_header */ ) {
    ret = GST_VP9_BIT_WRITER_NO_MORE_SPACE;
    goto out;
  }

  memset (data + data_sz, 0, 1 + 4 * frame_num + 1);
  gst_bit_writer_init_with_data (&bw, data + data_sz,
      1 + 4 * frame_num + 1, FALSE);

  /* superframe_header() */
  gst_bit_writer_put_bits_uint8 (&bw, GST_VP9_SUPERFRAME_MARKER, 3);
  /* bytes_per_framesize_minus_1 */
  gst_bit_writer_put_bits_uint8 (&bw, 4 - 1, 2);
  /* frames_in_superframe_minus_1 */
  gst_bit_writer_put_bits_uint8 (&bw, frame_num - 1, 3);

  for (i = 0; i < frame_num; i++) {
    guint32 value = frame_size[i];
    for (j = 0; j < 4; j++)
      gst_bit_writer_put_bits_uint8 (&bw, (value >> j * 8) & 0xff, 8);
  }

  /* superframe_header() again */
  gst_bit_writer_put_bits_uint8 (&bw, GST_VP9_SUPERFRAME_MARKER, 3);
  /* bytes_per_framesize_minus_1 */
  gst_bit_writer_put_bits_uint8 (&bw, 4 - 1, 2);
  /* frames_in_superframe_minus_1 */
  gst_bit_writer_put_bits_uint8 (&bw, frame_num - 1, 3);

  g_assert (gst_bit_writer_get_size (&bw) % 8 == 0);
  *size = data_sz + gst_bit_writer_get_size (&bw) / 8;

out:
  gst_bit_writer_reset (&bw);

  if (ret != GST_VP9_BIT_WRITER_OK)
    *size = 0;

  return ret;
}