/*
  * copyright (c) 2009 Michael Niedermayer
  *
  * 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 <strings.h>
 #include "avformat.h"

 #include "metadata.h"
 

 AVMetadataTag *

 av_metadata_get(AVMetadata *m, const char *key, const AVMetadataTag *prev, int flags)

 {
     unsigned int i, j;
 
     if(!m)
         return NULL;
 
     if(prev) i= prev - m->elems + 1;
     else     i= 0;
 
     for(; i<m->count; i++){
         const char *s= m->elems[i].key;

         if(flags & AV_METADATA_MATCH_CASE) for(j=0;         s[j]  ==         key[j]  && key[j]; j++);
         else                               for(j=0; toupper(s[j]) == toupper(key[j]) && key[j]; j++);

         if(key[j])
             continue;
         if(s[j] && !(flags & AV_METADATA_IGNORE_SUFFIX))
             continue;
         return &m->elems[i];
     }
     return NULL;
 }
 

 int av_metadata_set(AVMetadata **pm, const char *key, const char *value)

 {

     AVMetadata *m= *pm;

     AVMetadataTag *tag= av_metadata_get(m, key, NULL, AV_METADATA_MATCH_CASE);

 
     if(!m)
         m=*pm= av_mallocz(sizeof(*m));
 
     if(tag){
         av_free(tag->value);
         av_free(tag->key);
         *tag= m->elems[--m->count];
     }else{

         AVMetadataTag *tmp= av_realloc(m->elems, (m->count+1) * sizeof(*m->elems));

         if(tmp){
             m->elems= tmp;
         }else
             return AVERROR(ENOMEM);
     }

     if(value){
         m->elems[m->count].key  = av_strdup(key  );
         m->elems[m->count].value= av_strdup(value);
         m->count++;

     }

     if(!m->count) {
         av_free(m->elems);

         av_freep(pm);

     }

 
     return 0;
 }

 void av_metadata_free(AVMetadata **pm)
 {
     AVMetadata *m= *pm;
 
     if(m){
         while(m->count--){
             av_free(m->elems[m->count].key);
             av_free(m->elems[m->count].value);
         }
         av_free(m->elems);
     }
     av_freep(pm);
 }

 
 static void metadata_conv(AVMetadata **pm, const AVMetadataConv *d_conv,
                                            const AVMetadataConv *s_conv)
 {
     /* TODO: use binary search to look up the two conversion tables
        if the tables are getting big enough that it would matter speed wise */

     const AVMetadataConv *sc, *dc;

     AVMetadataTag *mtag = NULL;
     AVMetadata *dst = NULL;

     const char *key;

 
     while((mtag=av_metadata_get(*pm, "", mtag, AV_METADATA_IGNORE_SUFFIX))) {

         key = mtag->key;

         if (s_conv != d_conv) {

             if (s_conv)
                 for (sc=s_conv; sc->native; sc++)

                 if (!strcasecmp(key, sc->native)) {

                     key = sc->generic;

                     break;
                 }

             if (d_conv)
                 for (dc=d_conv; dc->native; dc++)
                     if (!strcasecmp(key, dc->generic)) {

                     key = dc->native;
                     break;
                 }
         }
         av_metadata_set(&dst, key, mtag->value);
     }
     av_metadata_free(pm);
     *pm = dst;
 }
 
 void av_metadata_conv(AVFormatContext *ctx, const AVMetadataConv *d_conv,
                                             const AVMetadataConv *s_conv)
 {
     int i;
     metadata_conv(&ctx->metadata, d_conv, s_conv);
     for (i=0; i<ctx->nb_streams ; i++)
         metadata_conv(&ctx->streams [i]->metadata, d_conv, s_conv);
     for (i=0; i<ctx->nb_chapters; i++)
         metadata_conv(&ctx->chapters[i]->metadata, d_conv, s_conv);
     for (i=0; i<ctx->nb_programs; i++)
         metadata_conv(&ctx->programs[i]->metadata, d_conv, s_conv);
 }