/********************************************************************

 *                                                                  *

 * THIS FILE IS PART OF THE OggVorbis 'TREMOR' CODEC SOURCE CODE.   *

 *                                                                  *

 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *

 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *

 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *

 *                                                                  *

 * THE OggVorbis 'TREMOR' SOURCE CODE IS (C) COPYRIGHT 1994-2002    *

 * BY THE Xiph.Org FOUNDATION http://www.xiph.org/                  *

 *                                                                  *

 ********************************************************************

 function: residue backend 0, 1 and 2 implementation

 ********************************************************************/

#include <stdlib.h>

#include <string.h>

#include <math.h>

#include <ogg/ogg.h>

#include "ivorbiscodec.h"

#include "codec_internal.h"

#include "registry.h"

#include "codebook.h"

#include "misc.h"

#include "os.h"

#include "block.h"

typedef struct {

  vorbis_info_residue0 *info;

  int         map;

  int         parts;

  int         stages;

  codebook   *fullbooks;

  codebook   *phrasebook;

  codebook ***partbooks;

  int         partvals;

  int       **decodemap;

} vorbis_look_residue0;

void res0_free_info(vorbis_info_residue *i){

  vorbis_info_residue0 *info=(vorbis_info_residue0 *)i;

  if(info){

    memset(info,0,sizeof(*info));

    _ogg_free(info);

  }

}

void res0_free_look(vorbis_look_residue *i){

  int j;

  if(i){

    vorbis_look_residue0 *look=(vorbis_look_residue0 *)i;

    for(j=0;j<look->parts;j++)

      if(look->partbooks[j])_ogg_free(look->partbooks[j]);

    _ogg_free(look->partbooks);

    for(j=0;j<look->partvals;j++)

      _ogg_free(look->decodemap[j]);

    _ogg_free(look->decodemap);

    memset(look,0,sizeof(*look));

    _ogg_free(look);

  }

}

static int ilog(unsigned int v){

  int ret=0;

  while(v){

    ret++;

    v>>=1;

  }

  return(ret);

}

static int icount(unsigned int v){

  int ret=0;

  while(v){

    ret+=v&1;

    v>>=1;

  }

  return(ret);

}

/* vorbis_info is for range checking */

vorbis_info_residue *res0_unpack(vorbis_info *vi,oggpack_buffer *opb){

  int j,acc=0;

  vorbis_info_residue0 *info=(vorbis_info_residue0 *)_ogg_calloc(1,sizeof(*info));

  codec_setup_info     *ci=(codec_setup_info *)vi->codec_setup;

  info->begin=oggpack_read(opb,24);

  info->end=oggpack_read(opb,24);

  info->grouping=oggpack_read(opb,24)+1;

  info->partitions=oggpack_read(opb,6)+1;

  info->groupbook=oggpack_read(opb,8);

  /* check for premature EOP */

  if(info->groupbook<0)goto errout;

  for(j=0;j<info->partitions;j++){

    int cascade=oggpack_read(opb,3);

    int cflag=oggpack_read(opb,1);

    if(cflag<0) goto errout;

    if(cflag){

      int c=oggpack_read(opb,5);

      if(c<0) goto errout;

      cascade|=(c<<3);

    }

    info->secondstages[j]=cascade;

    acc+=icount(cascade);

  }

  for(j=0;j<acc;j++){

    int book=oggpack_read(opb,8);

    if(book<0) goto errout;

    info->booklist[j]=book;

  }

  if(info->groupbook>=ci->books)goto errout;

  for(j=0;j<acc;j++){

    if(info->booklist[j]>=ci->books)goto errout;

    if(ci->book_param[info->booklist[j]]->maptype==0)goto errout;

  }

  /* verify the phrasebook is not specifying an impossible or

     inconsistent partitioning scheme. */

  /* modify the phrasebook ranging check from r16327; an early beta

     encoder had a bug where it used an oversized phrasebook by

     accident.  These files should continue to be playable, but don't

     allow an exploit */

  {

    int entries = ci->book_param[info->groupbook]->entries;

    int dim = ci->book_param[info->groupbook]->dim;

    int partvals = 1;

    if (dim<1) goto errout;

    while(dim>0){

      partvals *= info->partitions;

      if(partvals > entries) goto errout;

      dim--;

    }

    info->partvals = partvals;

  }

  return(info);

 errout:

  res0_free_info(info);

  return(NULL);

}

vorbis_look_residue *res0_look(vorbis_dsp_state *vd,vorbis_info_mode *vm,

        vorbis_info_residue *vr){

  vorbis_info_residue0 *info=(vorbis_info_residue0 *)vr;

  vorbis_look_residue0 *look=(vorbis_look_residue0 *)_ogg_calloc(1,sizeof(*look));

  codec_setup_info     *ci=(codec_setup_info *)vd->vi->codec_setup;

  int j,k,acc=0;

  int dim;

  int maxstage=0;

  look->info=info;

  look->map=vm->mapping;

  look->parts=info->partitions;

  look->fullbooks=ci->fullbooks;

  look->phrasebook=ci->fullbooks+info->groupbook;

  dim=look->phrasebook->dim;

  look->partbooks=(codebook ***)_ogg_calloc(look->parts,sizeof(*look->partbooks));

  for(j=0;j<look->parts;j++){

    int stages=ilog(info->secondstages[j]);

    if(stages){

      if(stages>maxstage)maxstage=stages;

      look->partbooks[j]=(codebook **)_ogg_calloc(stages,sizeof(*look->partbooks[j]));

      for(k=0;k<stages;k++)

  if(info->secondstages[j]&(1<<k)){

    look->partbooks[j][k]=ci->fullbooks+info->booklist[acc++];

#ifdef TRAIN_RES

    look->training_data[k][j]=calloc(look->partbooks[j][k]->entries,

             sizeof(***look->training_data));

#endif

  }

    }

  }

  look->partvals=look->parts;

  for(j=1;j<dim;j++)look->partvals*=look->parts;

  look->stages=maxstage;

  look->decodemap=(int **)_ogg_malloc(look->partvals*sizeof(*look->decodemap));

  for(j=0;j<look->partvals;j++){

    long val=j;

    long mult=look->partvals/look->parts;

    look->decodemap[j]=(int *)_ogg_malloc(dim*sizeof(*look->decodemap[j]));

    for(k=0;k<dim;k++){

      long deco=val/mult;

      val-=deco*mult;

      mult/=look->parts;

      look->decodemap[j][k]=deco;

    }

  }

  return(look);

}

/* a truncated packet here just means 'stop working'; it's not an error */

static int _01inverse(vorbis_block *vb,vorbis_look_residue *vl,

          ogg_int32_t **in,int ch,

          long (*decodepart)(codebook *, ogg_int32_t *, 

           oggpack_buffer *,int,int)){

  long i,j,k,l,s;

  vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;

  vorbis_info_residue0 *info=look->info;

  /* move all this setup out later */

  int samples_per_partition=info->grouping;

  int partitions_per_word=look->phrasebook->dim;

  int max=vb->pcmend>>1;

  int end=(info->end<max?info->end:max);

  int n=end-info->begin;

  if(n>0){

    int partvals=n/samples_per_partition;

    int partwords=(partvals+partitions_per_word-1)/partitions_per_word;

    int ***partword=(int ***)alloca(ch*sizeof(*partword));

    for(j=0;j<ch;j++)

      partword[j]=(int **)_vorbis_block_alloc(vb,partwords*sizeof(*partword[j]));

    for(s=0;s<look->stages;s++){

      /* each loop decodes on partition codeword containing 

   partitions_pre_word partitions */

      for(i=0,l=0;i<partvals;l++){

  if(s==0){

    /* fetch the partition word for each channel */

    for(j=0;j<ch;j++){

      int temp=vorbis_book_decode(look->phrasebook,&vb->opb);

      if(temp==-1 || temp>=info->partvals)goto eopbreak;

      partword[j][l]=look->decodemap[temp];

      if(partword[j][l]==NULL)goto errout;

    }

  }

  /* now we decode residual values for the partitions */

  for(k=0;k<partitions_per_word && i<partvals;k++,i++)

    for(j=0;j<ch;j++){

      long offset=info->begin+i*samples_per_partition;

      if(info->secondstages[partword[j][l][k]]&(1<<s)){

        codebook *stagebook=look->partbooks[partword[j][l][k]][s];

        if(stagebook){

    if(decodepart(stagebook,in[j]+offset,&vb->opb,

            samples_per_partition,-8)==-1)goto eopbreak;

        }

      }

    }

      } 

    }

  }

 errout:

 eopbreak:

  return(0);

}

int res0_inverse(vorbis_block *vb,vorbis_look_residue *vl,

     ogg_int32_t **in,int *nonzero,int ch){

  int i,used=0;

  for(i=0;i<ch;i++)

    if(nonzero[i])

      in[used++]=in[i];

  if(used)

    return(_01inverse(vb,vl,in,used,vorbis_book_decodevs_add));

  else

    return(0);

}

int res1_inverse(vorbis_block *vb,vorbis_look_residue *vl,

     ogg_int32_t **in,int *nonzero,int ch){

  int i,used=0;

  for(i=0;i<ch;i++)

    if(nonzero[i])

      in[used++]=in[i];

  if(used)

    return(_01inverse(vb,vl,in,used,vorbis_book_decodev_add));

  else

    return(0);

}

/* duplicate code here as speed is somewhat more important */

int res2_inverse(vorbis_block *vb,vorbis_look_residue *vl,

     ogg_int32_t **in,int *nonzero,int ch){

  long i,k,l,s;

  vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;

  vorbis_info_residue0 *info=look->info;

  /* move all this setup out later */

  int samples_per_partition=info->grouping;

  int partitions_per_word=look->phrasebook->dim;

  int max=(vb->pcmend*ch)>>1;

  int end=(info->end<max?info->end:max);

  int n=end-info->begin;

  if(n>0){

    int partvals=n/samples_per_partition;

    int partwords=(partvals+partitions_per_word-1)/partitions_per_word;

    int **partword=(int **)_vorbis_block_alloc(vb,partwords*sizeof(*partword));

    int beginoff=info->begin/ch;

    for(i=0;i<ch;i++)if(nonzero[i])break;

    if(i==ch)return(0); /* no nonzero vectors */

    samples_per_partition/=ch;

    for(s=0;s<look->stages;s++){

      for(i=0,l=0;i<partvals;l++){

  if(s==0){

    /* fetch the partition word */

    int temp=vorbis_book_decode(look->phrasebook,&vb->opb);

    if(temp==-1 || temp>=info->partvals)goto eopbreak;

    partword[l]=look->decodemap[temp];

    if(partword[l]==NULL)goto errout;

  }

  /* now we decode residual values for the partitions */

  for(k=0;k<partitions_per_word && i<partvals;k++,i++)

    if(info->secondstages[partword[l][k]]&(1<<s)){

      codebook *stagebook=look->partbooks[partword[l][k]][s];

      if(stagebook){

        if(vorbis_book_decodevv_add(stagebook,in,

            i*samples_per_partition+beginoff,ch,

            &vb->opb,

            samples_per_partition,-8)==-1)

    goto eopbreak;

      }

    }

      } 

    }

  }

 errout:

 eopbreak:

  return(0);

}

vorbis_func_residue residue0_exportbundle={

  &res0_unpack,

  &res0_look,

  &res0_free_info,

  &res0_free_look,

  &res0_inverse

};

vorbis_func_residue residue1_exportbundle={

  &res0_unpack,

  &res0_look,

  &res0_free_info,

  &res0_free_look,

  &res1_inverse

};

vorbis_func_residue residue2_exportbundle={

  &res0_unpack,

  &res0_look,

  &res0_free_info,

  &res0_free_look,

  &res2_inverse

};