/*
  * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
  *
  * 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
  */
 
 /**
  * @file

  * audio channel layout utility functions

  */
 

 #include <stdint.h>
 

 #include "avstring.h"
 #include "avutil.h"

 #include "channel_layout.h"

 #include "bprint.h"

 #include "common.h"

 struct channel_name {
     const char *name;
     const char *description;
 };
 
 static const struct channel_name channel_names[] = {
      [0] = { "FL",        "front left"            },
      [1] = { "FR",        "front right"           },
      [2] = { "FC",        "front center"          },
      [3] = { "LFE",       "low frequency"         },
      [4] = { "BL",        "back left"             },
      [5] = { "BR",        "back right"            },
      [6] = { "FLC",       "front left-of-center"  },
      [7] = { "FRC",       "front right-of-center" },
      [8] = { "BC",        "back center"           },
      [9] = { "SL",        "side left"             },
     [10] = { "SR",        "side right"            },
     [11] = { "TC",        "top center"            },
     [12] = { "TFL",       "top front left"        },
     [13] = { "TFC",       "top front center"      },
     [14] = { "TFR",       "top front right"       },
     [15] = { "TBL",       "top back left"         },
     [16] = { "TBC",       "top back center"       },
     [17] = { "TBR",       "top back right"        },
     [29] = { "DL",        "downmix left"          },
     [30] = { "DR",        "downmix right"         },
     [31] = { "WL",        "wide left"             },
     [32] = { "WR",        "wide right"            },
     [33] = { "SDL",       "surround direct left"  },
     [34] = { "SDR",       "surround direct right" },

     [35] = { "LFE2",      "low frequency 2"       },

 };
 
 static const char *get_channel_name(int channel_id)
 {
     if (channel_id < 0 || channel_id >= FF_ARRAY_ELEMS(channel_names))
         return NULL;

     return channel_names[channel_id].name;

 }
 
 static const struct {
     const char *name;
     int         nb_channels;

     uint64_t     layout;

 } channel_layout_map[] = {
     { "mono",        1,  AV_CH_LAYOUT_MONO },
     { "stereo",      2,  AV_CH_LAYOUT_STEREO },

     { "2.1",         3,  AV_CH_LAYOUT_2POINT1 },

     { "3.0",         3,  AV_CH_LAYOUT_SURROUND },
     { "3.0(back)",   3,  AV_CH_LAYOUT_2_1 },

     { "4.0",         4,  AV_CH_LAYOUT_4POINT0 },
     { "quad",        4,  AV_CH_LAYOUT_QUAD },

     { "quad(side)",  4,  AV_CH_LAYOUT_2_2 },

     { "3.1",         4,  AV_CH_LAYOUT_3POINT1 },

     { "5.0",         5,  AV_CH_LAYOUT_5POINT0_BACK },

     { "5.0(side)",   5,  AV_CH_LAYOUT_5POINT0 },

     { "4.1",         5,  AV_CH_LAYOUT_4POINT1 },

     { "5.1",         6,  AV_CH_LAYOUT_5POINT1_BACK },

     { "5.1(side)",   6,  AV_CH_LAYOUT_5POINT1 },

     { "6.0",         6,  AV_CH_LAYOUT_6POINT0 },
     { "6.0(front)",  6,  AV_CH_LAYOUT_6POINT0_FRONT },
     { "hexagonal",   6,  AV_CH_LAYOUT_HEXAGONAL },
     { "6.1",         7,  AV_CH_LAYOUT_6POINT1 },

     { "6.1(back)",   7,  AV_CH_LAYOUT_6POINT1_BACK },

     { "6.1(front)",  7,  AV_CH_LAYOUT_6POINT1_FRONT },
     { "7.0",         7,  AV_CH_LAYOUT_7POINT0 },
     { "7.0(front)",  7,  AV_CH_LAYOUT_7POINT0_FRONT },

     { "7.1",         8,  AV_CH_LAYOUT_7POINT1 },

     { "7.1(wide)",   8,  AV_CH_LAYOUT_7POINT1_WIDE_BACK },
     { "7.1(wide-side)",   8,  AV_CH_LAYOUT_7POINT1_WIDE },

     { "octagonal",   8,  AV_CH_LAYOUT_OCTAGONAL },

     { "hexadecagonal", 16, AV_CH_LAYOUT_HEXADECAGONAL },

     { "downmix",     2,  AV_CH_LAYOUT_STEREO_DOWNMIX, },

 };
 

 static uint64_t get_channel_layout_single(const char *name, int name_len)

 {

     int i;
     char *end;
     int64_t layout;

     for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++) {

         if (strlen(channel_layout_map[i].name) == name_len &&
             !memcmp(channel_layout_map[i].name, name, name_len))
             return channel_layout_map[i].layout;
     }
     for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++)

         if (channel_names[i].name &&
             strlen(channel_names[i].name) == name_len &&
             !memcmp(channel_names[i].name, name, name_len))

             return (int64_t)1 << i;

 
     errno = 0;

     i = strtol(name, &end, 10);

     if (!errno && (end + 1 - name == name_len && *end  == 'c'))

         return av_get_default_channel_layout(i);

     errno = 0;

     layout = strtoll(name, &end, 0);

     if (!errno && end - name == name_len)

         return FFMAX(layout, 0);

     return 0;
 }
 

 uint64_t av_get_channel_layout(const char *name)

 {
     const char *n, *e;
     const char *name_end = name + strlen(name);
     int64_t layout = 0, layout_single;
 
     for (n = name; n < name_end; n = e + 1) {
         for (e = n; e < name_end && *e != '+' && *e != '|'; e++);
         layout_single = get_channel_layout_single(n, e - n);
         if (!layout_single)
             return 0;
         layout |= layout_single;
     }
     return layout;
 }
 

 int av_get_extended_channel_layout(const char *name, uint64_t* channel_layout, int* nb_channels)
 {
     int nb = 0;
     char *end;
     uint64_t layout = av_get_channel_layout(name);
 
     if (layout) {
         *channel_layout = layout;
         *nb_channels = av_get_channel_layout_nb_channels(layout);
         return 0;
     }
 
     nb = strtol(name, &end, 10);
     if (!errno && *end  == 'C' && *(end + 1) == '\0' && nb > 0 && nb < 64) {
         *channel_layout = 0;
         *nb_channels = nb;
         return 0;
     }
 
     return AVERROR(EINVAL);
 }
 

 void av_bprint_channel_layout(struct AVBPrint *bp,
                               int nb_channels, uint64_t channel_layout)

 {
     int i;
 

     if (nb_channels <= 0)
         nb_channels = av_get_channel_layout_nb_channels(channel_layout);
 

     for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++)

         if (nb_channels    == channel_layout_map[i].nb_channels &&
             channel_layout == channel_layout_map[i].layout) {

             av_bprintf(bp, "%s", channel_layout_map[i].name);

             return;
         }
 

     av_bprintf(bp, "%d channels", nb_channels);

     if (channel_layout) {

         int i, ch;

         av_bprintf(bp, " (");

         for (i = 0, ch = 0; i < 64; i++) {

             if ((channel_layout & (UINT64_C(1) << i))) {

                 const char *name = get_channel_name(i);
                 if (name) {

                     if (ch > 0)

                         av_bprintf(bp, "+");
                     av_bprintf(bp, "%s", name);

                 }
                 ch++;
             }
         }

         av_bprintf(bp, ")");

     }
 }
 

 void av_get_channel_layout_string(char *buf, int buf_size,
                                   int nb_channels, uint64_t channel_layout)
 {
     AVBPrint bp;
 
     av_bprint_init_for_buffer(&bp, buf, buf_size);
     av_bprint_channel_layout(&bp, nb_channels, channel_layout);
 }
 

 int av_get_channel_layout_nb_channels(uint64_t channel_layout)

 {

     return av_popcount64(channel_layout);

 }

 int64_t av_get_default_channel_layout(int nb_channels) {

     int i;

     for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++)

         if (nb_channels == channel_layout_map[i].nb_channels)
             return channel_layout_map[i].layout;
     return 0;
 }

 
 int av_get_channel_layout_channel_index(uint64_t channel_layout,
                                         uint64_t channel)
 {
     if (!(channel_layout & channel) ||
         av_get_channel_layout_nb_channels(channel) != 1)
         return AVERROR(EINVAL);
     channel_layout &= channel - 1;
     return av_get_channel_layout_nb_channels(channel_layout);
 }

 
 const char *av_get_channel_name(uint64_t channel)
 {
     int i;
     if (av_get_channel_layout_nb_channels(channel) != 1)
         return NULL;
     for (i = 0; i < 64; i++)
         if ((1ULL<<i) & channel)
             return get_channel_name(i);
     return NULL;
 }

 const char *av_get_channel_description(uint64_t channel)
 {
     int i;
     if (av_get_channel_layout_nb_channels(channel) != 1)
         return NULL;
     for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++)
         if ((1ULL<<i) & channel)
             return channel_names[i].description;
     return NULL;
 }
 

 uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index)
 {
     int i;
 
     if (av_get_channel_layout_nb_channels(channel_layout) <= index)
         return 0;
 
     for (i = 0; i < 64; i++) {
         if ((1ULL << i) & channel_layout && !index--)
             return 1ULL << i;
     }
     return 0;
 }

 
 int av_get_standard_channel_layout(unsigned index, uint64_t *layout,
                                    const char **name)
 {
     if (index >= FF_ARRAY_ELEMS(channel_layout_map))
         return AVERROR_EOF;
     if (layout) *layout = channel_layout_map[index].layout;
     if (name)   *name   = channel_layout_map[index].name;
     return 0;
 }