/*
  * WMA compatible codec

  * Copyright (c) 2002-2007 The FFmpeg Project

  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg 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
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include "avcodec.h"
 #include "wma.h"
 #include "wmadata.h"
 
 #undef NDEBUG
 #include <assert.h>
 
 /* XXX: use same run/length optimization as mpeg decoders */
 //FIXME maybe split decode / encode or pass flag
 static void init_coef_vlc(VLC *vlc,
                           uint16_t **prun_table, uint16_t **plevel_table, uint16_t **pint_table,
                           const CoefVLCTable *vlc_table)
 {
     int n = vlc_table->n;
     const uint8_t *table_bits = vlc_table->huffbits;
     const uint32_t *table_codes = vlc_table->huffcodes;
     const uint16_t *levels_table = vlc_table->levels;
     uint16_t *run_table, *level_table, *int_table;
     int i, l, j, k, level;
 
     init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4, 0);
 
     run_table = av_malloc(n * sizeof(uint16_t));
     level_table = av_malloc(n * sizeof(uint16_t));
     int_table = av_malloc(n * sizeof(uint16_t));
     i = 2;
     level = 1;
     k = 0;
     while (i < n) {
         int_table[k]= i;
         l = levels_table[k++];
         for(j=0;j<l;j++) {
             run_table[i] = j;
             level_table[i] = level;
             i++;
         }
         level++;
     }
     *prun_table = run_table;
     *plevel_table = level_table;
     *pint_table= int_table;
 }
 
 int ff_wma_init(AVCodecContext * avctx, int flags2)
 {

     WMACodecContext *s = avctx->priv_data;

     int i;
     float bps1, high_freq;
     volatile float bps;
     int sample_rate1;
     int coef_vlc_table;
 

     if(   avctx->sample_rate<=0 || avctx->sample_rate>50000
        || avctx->channels<=0 || avctx->channels>8
        || avctx->bit_rate<=0)
         return -1;
 

     s->sample_rate = avctx->sample_rate;
     s->nb_channels = avctx->channels;
     s->bit_rate = avctx->bit_rate;
     s->block_align = avctx->block_align;
 
     dsputil_init(&s->dsp, avctx);
 
     if (avctx->codec->id == CODEC_ID_WMAV1) {
         s->version = 1;
     } else {
         s->version = 2;
     }
 
     /* compute MDCT block size */
     if (s->sample_rate <= 16000) {
         s->frame_len_bits = 9;
     } else if (s->sample_rate <= 22050 ||
                (s->sample_rate <= 32000 && s->version == 1)) {
         s->frame_len_bits = 10;
     } else {
         s->frame_len_bits = 11;
     }
     s->frame_len = 1 << s->frame_len_bits;
     if (s->use_variable_block_len) {
         int nb_max, nb;
         nb = ((flags2 >> 3) & 3) + 1;
         if ((s->bit_rate / s->nb_channels) >= 32000)
             nb += 2;
         nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
         if (nb > nb_max)
             nb = nb_max;
         s->nb_block_sizes = nb + 1;
     } else {
         s->nb_block_sizes = 1;
     }
 

     /* init rate dependent parameters */

     s->use_noise_coding = 1;
     high_freq = s->sample_rate * 0.5;
 
     /* if version 2, then the rates are normalized */
     sample_rate1 = s->sample_rate;
     if (s->version == 2) {
         if (sample_rate1 >= 44100)
             sample_rate1 = 44100;
         else if (sample_rate1 >= 22050)
             sample_rate1 = 22050;
         else if (sample_rate1 >= 16000)
             sample_rate1 = 16000;
         else if (sample_rate1 >= 11025)
             sample_rate1 = 11025;
         else if (sample_rate1 >= 8000)
             sample_rate1 = 8000;
     }
 
     bps = (float)s->bit_rate / (float)(s->nb_channels * s->sample_rate);
     s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0 + 0.5)) + 2;
 
     /* compute high frequency value and choose if noise coding should
        be activated */
     bps1 = bps;
     if (s->nb_channels == 2)
         bps1 = bps * 1.6;
     if (sample_rate1 == 44100) {
         if (bps1 >= 0.61)
             s->use_noise_coding = 0;
         else
             high_freq = high_freq * 0.4;
     } else if (sample_rate1 == 22050) {
         if (bps1 >= 1.16)
             s->use_noise_coding = 0;
         else if (bps1 >= 0.72)
             high_freq = high_freq * 0.7;
         else
             high_freq = high_freq * 0.6;
     } else if (sample_rate1 == 16000) {
         if (bps > 0.5)
             high_freq = high_freq * 0.5;
         else
             high_freq = high_freq * 0.3;
     } else if (sample_rate1 == 11025) {
         high_freq = high_freq * 0.7;
     } else if (sample_rate1 == 8000) {
         if (bps <= 0.625) {
             high_freq = high_freq * 0.5;
         } else if (bps > 0.75) {
             s->use_noise_coding = 0;
         } else {
             high_freq = high_freq * 0.65;
         }
     } else {
         if (bps >= 0.8) {
             high_freq = high_freq * 0.75;
         } else if (bps >= 0.6) {
             high_freq = high_freq * 0.6;
         } else {
             high_freq = high_freq * 0.5;
         }
     }

     dprintf(s->avctx, "flags2=0x%x\n", flags2);
     dprintf(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",

            s->version, s->nb_channels, s->sample_rate, s->bit_rate,
            s->block_align);

     dprintf(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",

            bps, bps1, high_freq, s->byte_offset_bits);

     dprintf(s->avctx, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",

            s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
 
     /* compute the scale factor band sizes for each MDCT block size */
     {
         int a, b, pos, lpos, k, block_len, i, j, n;
         const uint8_t *table;
 
         if (s->version == 1) {
             s->coefs_start = 3;
         } else {
             s->coefs_start = 0;
         }
         for(k = 0; k < s->nb_block_sizes; k++) {
             block_len = s->frame_len >> k;
 
             if (s->version == 1) {
                 lpos = 0;
                 for(i=0;i<25;i++) {
                     a = wma_critical_freqs[i];
                     b = s->sample_rate;
                     pos = ((block_len * 2 * a)  + (b >> 1)) / b;
                     if (pos > block_len)
                         pos = block_len;
                     s->exponent_bands[0][i] = pos - lpos;
                     if (pos >= block_len) {
                         i++;
                         break;
                     }
                     lpos = pos;
                 }
                 s->exponent_sizes[0] = i;
             } else {
                 /* hardcoded tables */
                 table = NULL;
                 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
                 if (a < 3) {
                     if (s->sample_rate >= 44100)
                         table = exponent_band_44100[a];
                     else if (s->sample_rate >= 32000)
                         table = exponent_band_32000[a];
                     else if (s->sample_rate >= 22050)
                         table = exponent_band_22050[a];
                 }
                 if (table) {
                     n = *table++;
                     for(i=0;i<n;i++)
                         s->exponent_bands[k][i] = table[i];
                     s->exponent_sizes[k] = n;
                 } else {
                     j = 0;
                     lpos = 0;
                     for(i=0;i<25;i++) {
                         a = wma_critical_freqs[i];
                         b = s->sample_rate;
                         pos = ((block_len * 2 * a)  + (b << 1)) / (4 * b);
                         pos <<= 2;
                         if (pos > block_len)
                             pos = block_len;
                         if (pos > lpos)
                             s->exponent_bands[k][j++] = pos - lpos;
                         if (pos >= block_len)
                             break;
                         lpos = pos;
                     }
                     s->exponent_sizes[k] = j;
                 }
             }
 
             /* max number of coefs */
             s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
             /* high freq computation */
             s->high_band_start[k] = (int)((block_len * 2 * high_freq) /
                                           s->sample_rate + 0.5);
             n = s->exponent_sizes[k];
             j = 0;
             pos = 0;
             for(i=0;i<n;i++) {
                 int start, end;
                 start = pos;
                 pos += s->exponent_bands[k][i];
                 end = pos;
                 if (start < s->high_band_start[k])
                     start = s->high_band_start[k];
                 if (end > s->coefs_end[k])
                     end = s->coefs_end[k];
                 if (end > start)
                     s->exponent_high_bands[k][j++] = end - start;
             }
             s->exponent_high_sizes[k] = j;
 #if 0

             tprintf(s->avctx, "%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",

                   s->frame_len >> k,
                   s->coefs_end[k],
                   s->high_band_start[k],
                   s->exponent_high_sizes[k]);
             for(j=0;j<s->exponent_high_sizes[k];j++)

                 tprintf(s->avctx, " %d", s->exponent_high_bands[k][j]);
             tprintf(s->avctx, "\n");

 #endif
         }
     }
 
 #ifdef TRACE
     {
         int i, j;
         for(i = 0; i < s->nb_block_sizes; i++) {

             tprintf(s->avctx, "%5d: n=%2d:",

                    s->frame_len >> i,
                    s->exponent_sizes[i]);
             for(j=0;j<s->exponent_sizes[i];j++)

                 tprintf(s->avctx, " %d", s->exponent_bands[i][j]);
             tprintf(s->avctx, "\n");

         }
     }
 #endif
 
     /* init MDCT windows : simple sinus window */
     for(i = 0; i < s->nb_block_sizes; i++) {

         int n;

         n = 1 << (s->frame_len_bits - i);

         ff_sine_window_init(ff_sine_windows[s->frame_len_bits - i - 7], n);
         s->windows[i] = ff_sine_windows[s->frame_len_bits - i - 7];

     }
 
     s->reset_block_lengths = 1;
 
     if (s->use_noise_coding) {
 
         /* init the noise generator */
         if (s->use_exp_vlc)
             s->noise_mult = 0.02;
         else
             s->noise_mult = 0.04;
 
 #ifdef TRACE
         for(i=0;i<NOISE_TAB_SIZE;i++)
             s->noise_table[i] = 1.0 * s->noise_mult;
 #else
         {
             unsigned int seed;
             float norm;
             seed = 1;
             norm = (1.0 / (float)(1LL << 31)) * sqrt(3) * s->noise_mult;
             for(i=0;i<NOISE_TAB_SIZE;i++) {
                 seed = seed * 314159 + 1;
                 s->noise_table[i] = (float)((int)seed) * norm;
             }
         }
 #endif
     }
 
     /* choose the VLC tables for the coefficients */
     coef_vlc_table = 2;
     if (s->sample_rate >= 32000) {
         if (bps1 < 0.72)
             coef_vlc_table = 0;
         else if (bps1 < 1.16)
             coef_vlc_table = 1;
     }
     s->coef_vlcs[0]= &coef_vlcs[coef_vlc_table * 2    ];
     s->coef_vlcs[1]= &coef_vlcs[coef_vlc_table * 2 + 1];
     init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0], &s->int_table[0],
                   s->coef_vlcs[0]);
     init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1], &s->int_table[1],
                   s->coef_vlcs[1]);
 
     return 0;
 }
 
 int ff_wma_total_gain_to_bits(int total_gain){
          if (total_gain < 15) return 13;
     else if (total_gain < 32) return 12;
     else if (total_gain < 40) return 11;
     else if (total_gain < 45) return 10;
     else                      return  9;
 }
 
 int ff_wma_end(AVCodecContext *avctx)
 {

     WMACodecContext *s = avctx->priv_data;

     int i;
 
     for(i = 0; i < s->nb_block_sizes; i++)
         ff_mdct_end(&s->mdct_ctx[i]);
 
     if (s->use_exp_vlc) {
         free_vlc(&s->exp_vlc);
     }
     if (s->use_noise_coding) {
         free_vlc(&s->hgain_vlc);
     }
     for(i = 0;i < 2; i++) {
         free_vlc(&s->coef_vlc[i]);
         av_free(s->run_table[i]);
         av_free(s->level_table[i]);

         av_free(s->int_table[i]);

     }
 
     return 0;
 }