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

#include "os_support.h"
#include "entenc.h"
#include "arch.h"


#define EC_BUFFER_INCREMENT (256)

void ec_byte_writeinit_buffer(ec_byte_buffer *_b, unsigned char *_buf, long _size){
  _b->ptr=_b->buf=_buf;
  _b->storage=_size;
  _b->resizable = 0;
}

void ec_byte_writeinit(ec_byte_buffer *_b){
  _b->ptr=_b->buf=celt_alloc(EC_BUFFER_INCREMENT*sizeof(char));
  _b->storage=EC_BUFFER_INCREMENT;
  _b->resizable = 1;
}

void ec_byte_writetrunc(ec_byte_buffer *_b,long _bytes){
  _b->ptr=_b->buf+_bytes;
}

void ec_byte_write1(ec_byte_buffer *_b,unsigned _value){
  ptrdiff_t endbyte;
  endbyte=_b->ptr-_b->buf;
  if(endbyte>=_b->storage){
    if (_b->resizable){
      _b->buf=celt_realloc(_b->buf,(_b->storage+EC_BUFFER_INCREMENT)*sizeof(char));
      _b->storage+=EC_BUFFER_INCREMENT;
      _b->ptr=_b->buf+endbyte;
    } else {
      celt_fatal("range encoder overflow\n");
    }
  }
  *(_b->ptr++)=(unsigned char)_value;
}

void ec_byte_write4(ec_byte_buffer *_b,ec_uint32 _value){
  ptrdiff_t endbyte;
  endbyte=_b->ptr-_b->buf;
  if(endbyte+4>_b->storage){
    if (_b->resizable){
      _b->buf=celt_realloc(_b->buf,(_b->storage+EC_BUFFER_INCREMENT)*sizeof(char));
      _b->storage+=EC_BUFFER_INCREMENT;
      _b->ptr=_b->buf+endbyte;
    } else {
      celt_fatal("range encoder overflow\n");
    }
  }
  *(_b->ptr++)=(unsigned char)_value;
  _value>>=8;
  *(_b->ptr++)=(unsigned char)_value;
  _value>>=8;
  *(_b->ptr++)=(unsigned char)_value;
  _value>>=8;
  *(_b->ptr++)=(unsigned char)_value;
}

void ec_byte_writecopy(ec_byte_buffer *_b,void *_source,long _bytes){
  ptrdiff_t endbyte;
  endbyte=_b->ptr-_b->buf;
  if(endbyte+_bytes>_b->storage){
    if (_b->resizable){
      _b->storage=endbyte+_bytes+EC_BUFFER_INCREMENT;
      _b->buf=celt_realloc(_b->buf,_b->storage*sizeof(char));
      _b->ptr=_b->buf+endbyte;
    } else {
      celt_fatal("range encoder overflow\n");
    }
  }
  memmove(_b->ptr,_source,_bytes);
  _b->ptr+=_bytes;
}

void ec_byte_writeclear(ec_byte_buffer *_b){
  celt_free(_b->buf);
}



void ec_enc_bits(ec_enc *_this,ec_uint32 _fl,int _ftb){
  unsigned fl;
  unsigned ft;
  while(_ftb>EC_UNIT_BITS){
    _ftb-=EC_UNIT_BITS;
    fl=(unsigned)(_fl>>_ftb)&EC_UNIT_MASK;
    ec_encode_bin(_this,fl,fl+1,EC_UNIT_BITS);
  }
  ft=1<<_ftb;
  fl=(unsigned)_fl&ft-1;
  ec_encode_bin(_this,fl,fl+1,_ftb);
}

void ec_enc_uint(ec_enc *_this,ec_uint32 _fl,ec_uint32 _ft){
  unsigned  ft;
  unsigned  fl;
  int       ftb;
  _ft--;
  ftb=EC_ILOG(_ft)&-!!_ft;
  if(ftb>EC_UNIT_BITS){
    ftb-=EC_UNIT_BITS;
    ft=(_ft>>ftb)+1;
    fl=(unsigned)(_fl>>ftb);
    ec_encode(_this,fl,fl+1,ft);
    ec_enc_bits(_this,_fl,ftb);
  } else {
    ec_encode(_this,_fl,_fl+1,_ft+1);
  }
}