/*!
 ***********************************************************************
 *  \file
 *      mbuffer.c
 *
 *  \brief
 *      Frame buffer functions
 *
 *  \author
 *      Main contributors (see contributors.h for copyright, address and affiliation details)
 *      - Karsten S黨ring          <suehring@hhi.de>
 ***********************************************************************
 */

#include <stdlib.h>
#include <memory.h>
#include <assert.h>
#include <limits.h>

#include "global.h"
#include "mbuffer.h"
#include "memalloc.h"
#include "output.h"
#include "image.h"


//-------- start new Buffer code -----------------------------
static void insert_picture_in_dpb(FrameStore* fs, StorablePicture* p);
static void output_one_frame_from_dpb();
static int  is_used_for_reference(FrameStore* fs);
static void get_smallest_poc(int *poc,int * pos);
static int  remove_unused_frame_from_dpb();
static int  is_short_term_reference(FrameStore* fs);
static int  is_long_term_reference(FrameStore* fs);

DecodedPictureBuffer dpb;

StorablePicture **listX[6];

int listXsize[6];

/*!
 ************************************************************************
 * \brief
 *    Print out list of pictures in DPB. Used for debug purposes.
 ************************************************************************
 */
void dump_dpb()
{
  unsigned i;

  return;
  
  for (i=0; i<dpb.used_size;i++)
  {
    printf("(");
    printf("fn=%d  ", dpb.fs[i]->frame_num);
    if (dpb.fs[i]->is_used & 1)
      printf("T: poc=%d  ", dpb.fs[i]->top_field->poc);
    if (dpb.fs[i]->is_used & 2)
      printf("B: poc=%d  ", dpb.fs[i]->bottom_field->poc);
    if (dpb.fs[i]->is_used == 3)
      printf("F: poc=%d  ", dpb.fs[i]->frame->poc);
    printf("G: poc=%d)  ", dpb.fs[i]->poc);
    if (dpb.fs[i]->is_reference) printf ("ref  ");
    if (dpb.fs[i]->is_output) printf ("out  ");
    printf ("\n");
  }
}


/*!
 ************************************************************************
 * \brief
 *    Allocate memory for decoded picture buffer an initialize with sane values.
 *
 * \param inp
 *    Input Parameters
 *
 ************************************************************************
 */
void init_dpb(InputParameters *inp)
{
  unsigned i,j;

  dpb.size      = inp->num_reference_frames;
  dpb.used_size = 0;

  dpb.fs = calloc(dpb.size, sizeof (FrameStore*));
  if (NULL==dpb.fs) 
    no_mem_exit("init_dpb: dpb->fs");

  dpb.fs_ref = calloc(dpb.size, sizeof (FrameStore*));
  if (NULL==dpb.fs_ref) 
    no_mem_exit("init_dpb: dpb->fs_ref");

  dpb.fs_ltref = calloc(dpb.size, sizeof (FrameStore*));
  if (NULL==dpb.fs_ltref) 
    no_mem_exit("init_dpb: dpb->fs_ltref");

  for (i=0; i<dpb.size; i++)
  {
    dpb.fs[i]       = alloc_frame_store();
    dpb.fs_ref[i]   = NULL;
    dpb.fs_ltref[i] = NULL;
  }
  
  for (i=0; i<6; i++)
  {
    listX[i] = calloc(dpb.size * 2 + 1, sizeof (StorablePicture*)); // +1 for reordering
    if (NULL==listX[i]) 
      no_mem_exit("init_dpb: listX[i]");
  }

  for (j=0;j<6;j++)
  {
    for (i=0; i<(2*dpb.size)+1; i++)
    {
      listX[j][i] = NULL;
    }
    listXsize[j]=0;
  }

  dpb.last_output_poc = INT_MIN;
}


/*!
 ************************************************************************
 * \brief
 *    Free memory for decoded picture buffer.
 ************************************************************************
 */
void free_dpb()
{
  unsigned i;
  if (dpb.fs)
  {
    for (i=0; i<dpb.size; i++)
    {
      free_frame_store(dpb.fs[i]);
    }
    free (dpb.fs);
    dpb.fs=NULL;
  }
  if (dpb.fs_ref)
  {
    free (dpb.fs_ref);
  }
  if (dpb.fs_ltref)
  {
    free (dpb.fs_ltref);
  }
  dpb.last_output_poc = INT_MIN;

  for (i=0; i<6; i++)
    if (listX[i])
    {
      free (listX[i]);
      listX[i] = NULL;
    }
}


/*!
 ************************************************************************
 * \brief
 *    Allocate memory for decoded picture buffer frame stores an initialize with sane values.
 *
 * \return
 *    the allocated FrameStore structure
 ************************************************************************
 */
FrameStore* alloc_frame_store()
{
  FrameStore *f;

  f = calloc (1, sizeof(FrameStore));
  if (NULL==f) 
    no_mem_exit("alloc_frame_store: f");

  f->is_used      = 0;
  f->is_reference = 0;

  f->is_output = 0;

  f->frame        = NULL;;
  f->top_field    = NULL;
  f->bottom_field = NULL;

  return f;
}

/*!
 ************************************************************************
 * \brief
 *    Allocate memory for a stored picture. 
 *
 * \param size_x
 *    horizontal luma size
 * \param size_y
 *    vertical luma size
 * \param size_x_cr
 *    horizontal chroma size
 * \param size_y_cr
 *    vertical chroma size
 *
 * \return
 *    the allocated StorablePicture structure
 ************************************************************************
 */
StorablePicture* alloc_storable_picture(PictureStructure structure, int size_x, int size_y, int size_x_cr, int size_y_cr)
{
  StorablePicture *s;

  //printf ("Allocating (%s) picture (x=%d, y=%d, x_cr=%d, y_cr=%d)\n", (type == FRAME)?"FRAME":(type == TOP_FIELD)?"TOP_FIELD":"BOTTOM_FIELD", size_x, size_y, size_x_cr, size_y_cr);

  s = calloc (1, sizeof(StorablePicture));
  if (NULL==s) 
    no_mem_exit("alloc_storable_picture: s");

  get_mem2D (&(s->imgY), size_y, size_x);
  
  s->imgY_11 = NULL;
  s->imgY_ups = NULL;

  get_mem3D (&(s->imgUV), 2, size_y_cr, size_x_cr );

  s->mb_field = calloc (img->PicSizeInMbs, sizeof(int));

  get_mem3Dint (&(s->ref_idx), 2, size_x / BLOCK_SIZE, size_y / BLOCK_SIZE);
  get_mem4Dint (&(s->mv), 2, size_x / BLOCK_SIZE, size_y / BLOCK_SIZE,2 );

  s->pic_num=0;
  s->long_term_frame_idx=0;
  s->long_term_pic_num=0;
  s->used_for_reference=0;
  s->is_long_term=0;

  s->structure=structure;

  s->size_x = size_x;
  s->size_y = size_y;
  s->size_x_cr = size_x_cr;
  s->size_y_cr = size_y_cr;
  
  s->top_field    = NULL;
  s->bottom_field = NULL;
  s->frame        = NULL;

  s->coded_frame                   = 0;
  s->mb_adaptive_frame_field_flag  = 0;

  return s;
}

/*!
 ************************************************************************
 * \brief
 *    Free frame store memory.
 *
 * \param f
 *    FrameStore to be freed
 *
 ************************************************************************
 */
void free_frame_store(FrameStore* f)
{
  if (f)
  {
    if (f->frame)
    {
      free_storable_picture(f->frame);
      f->frame=NULL;
    }
    if (f->top_field)
    {
      free_storable_picture(f->top_field);
      f->top_field=NULL;
    }
    if (f->bottom_field)
    {
      free_storable_picture(f->bottom_field);
      f->bottom_field=NULL;
    }
    free(f);
  }
}

/*!
 ************************************************************************
 * \brief
 *    Free picture memory.
 *
 * \param p
 *    Picture to be freed
 *
 ************************************************************************
 */
void free_storable_picture(StorablePicture* p)
{
  if (p)
  {
    free_mem3Dint (p->ref_idx, 2);
    free_mem4Dint (p->mv, 2, p->size_x / BLOCK_SIZE);
    
    if (p->imgY)
    {
      free_mem2D (p->imgY);
      p->imgY=NULL;
    }
    if (p->imgY_11)
    {
      free (p->imgY_11);
      p->imgY_11=NULL;
    }
    if (p->imgY_ups)
    {
      free_mem2D (p->imgY_ups);
      p->imgY_ups=NULL;
    }
    if (p->imgUV)
    {
      free_mem3D (p->imgUV, 2);
      p->imgUV=NULL;
    }
    free(p);
  }
}

/*!
 ************************************************************************
 * \brief
 *    mark FrameStore unused for reference
 *
 ************************************************************************
 */
static void unmark_for_reference(FrameStore* fs)
{

  if (fs->is_used & 1)
  {
    fs->top_field->used_for_reference = 0;
  }
  if (fs->is_used & 2)
  {
    fs->bottom_field->used_for_reference = 0;
  }
  if (fs->is_used == 3)
  {
    fs->frame->used_for_reference = 0;
  }

  fs->is_reference = 0;
}


/*!
 ************************************************************************
 * \brief
 *    mark FrameStore unused for reference and reset long term flags
 *
 ************************************************************************
 */
static void unmark_for_long_term_reference(FrameStore* fs)
{

  if (fs->is_used & 1)
  {
    fs->top_field->used_for_reference = 0;
    fs->top_field->is_long_term = 0;
  }
  if (fs->is_used & 2)
  {
    fs->bottom_field->used_for_reference = 0;
    fs->bottom_field->is_long_term = 0;
  }
  if (fs->is_used == 3)
  {
    fs->frame->used_for_reference = 0;
    fs->frame->is_long_term = 0;
  }

  fs->is_reference = 0;
  fs->is_long_term = 0;
}


/*!
 ************************************************************************
 * \brief
 *    compares two stored pictures by picture number for qsort in descending order
 *
 ************************************************************************
 */
static int compare_pic_by_pic_num_desc( const void *arg1, const void *arg2 )
{
  if ( (*(StorablePicture**)arg1)->pic_num < (*(StorablePicture**)arg2)->pic_num)
    return 1;
  if ( (*(StorablePicture**)arg1)->pic_num > (*(StorablePicture**)arg2)->pic_num)
    return -1;
  else
    return 0;
}

/*!
 ************************************************************************
 * \brief
 *    compares two stored pictures by picture number for qsort in descending order
 *
 ************************************************************************
 */
static int compare_pic_by_lt_pic_num_asc( const void *arg1, const void *arg2 )
{
  if ( (*(StorablePicture**)arg1)->long_term_pic_num < (*(StorablePicture**)arg2)->long_term_pic_num)
    return -1;
  if ( (*(StorablePicture**)arg1)->long_term_pic_num > (*(StorablePicture**)arg2)->long_term_pic_num)
    return 1;
  else
    return 0;
}

/*!
 ************************************************************************
 * \brief
 *    compares two frame stores by pic_num for qsort in descending order
 *
 ************************************************************************
 */
static int compare_fs_by_frame_num_desc( const void *arg1, const void *arg2 )
{
  if ( (*(FrameStore**)arg1)->frame_num < (*(FrameStore**)arg2)->frame_num)
    return 1;
  if ( (*(FrameStore**)arg1)->frame_num > (*(FrameStore**)arg2)->frame_num)
    return -1;
  else
    return 0;
}


/*!
 ************************************************************************
 * \brief
 *    compares two frame stores by lt_pic_num for qsort in descending order
 *
 ************************************************************************
 */
static int compare_fs_by_lt_pic_idx_asc( const void *arg1, const void *arg2 )
{
  if ( (*(FrameStore**)arg1)->long_term_frame_idx < (*(FrameStore**)arg2)->long_term_frame_idx)
    return -1;
  if ( (*(FrameStore**)arg1)->long_term_frame_idx > (*(FrameStore**)arg2)->long_term_frame_idx)
    return 1;
  else
    return 0;
}


/*!
 ************************************************************************
 * \brief
 *    compares two stored pictures by poc for qsort in ascending order
 *