/*
  * 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
 * ModPlug demuxer

 * @todo better probing than extensions matching

 */
 

 #define MODPLUG_STATIC

 #include <libmodplug/modplug.h>

 #include "libavutil/avstring.h"

 #include "libavutil/eval.h"

 #include "libavutil/opt.h"

 #include "avformat.h"

 #include "internal.h"

 
 typedef struct ModPlugContext {

     const AVClass *class;

     ModPlugFile *f;

     uint8_t *buf; ///< input file content

 
     /* options */
     int noise_reduction;
     int reverb_depth;
     int reverb_delay;
     int bass_amount;
     int bass_range;
     int surround_depth;
     int surround_delay;

 
     int max_size; ///< max file size to allocate

 
     /* optional video stream */
     double ts_per_packet; ///< used to define the pts/dts using packet_count;
     int packet_count;     ///< total number of audio packets
     int print_textinfo;   ///< bool flag for printing speed, tempo, order, ...
     int video_stream;     ///< 1 if the user want a video stream, otherwise 0
     int w;                ///< video stream width  in char (one char = 8x8px)
     int h;                ///< video stream height in char (one char = 8x8px)
     int video_switch;     ///< 1 if current packet is video, otherwise 0
     int fsize;            ///< constant frame size
     int linesize;         ///< line size in bytes
     char *color_eval;     ///< color eval user input expression

     AVExpr *expr;         ///< parsed color eval expression

 } ModPlugContext;
 

 static const char * const var_names[] = {

     "x", "y",
     "w", "h",
     "t",
     "speed", "tempo", "order", "pattern", "row",
     NULL
 };
 
 enum var_name {
     VAR_X, VAR_Y,
     VAR_W, VAR_H,
     VAR_TIME,
     VAR_SPEED, VAR_TEMPO, VAR_ORDER, VAR_PATTERN, VAR_ROW,
     VAR_VARS_NB
 };
 

 #define FF_MODPLUG_MAX_FILE_SIZE (100 * 1<<20) // 100M
 #define FF_MODPLUG_DEF_FILE_SIZE (  5 * 1<<20) //   5M
 

 #define OFFSET(x) offsetof(ModPlugContext, x)
 #define D AV_OPT_FLAG_DECODING_PARAM
 static const AVOption options[] = {

     {"noise_reduction", "Enable noise reduction 0(off)-1(on)",  OFFSET(noise_reduction), AV_OPT_TYPE_INT, {.i64 = 0}, 0,       1, D},
     {"reverb_depth",    "Reverb level 0(quiet)-100(loud)",      OFFSET(reverb_depth),    AV_OPT_TYPE_INT, {.i64 = 0}, 0,     100, D},
     {"reverb_delay",    "Reverb delay in ms, usually 40-200ms", OFFSET(reverb_delay),    AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, D},
     {"bass_amount",     "XBass level 0(quiet)-100(loud)",       OFFSET(bass_amount),     AV_OPT_TYPE_INT, {.i64 = 0}, 0,     100, D},
     {"bass_range",      "XBass cutoff in Hz 10-100",            OFFSET(bass_range),      AV_OPT_TYPE_INT, {.i64 = 0}, 0,     100, D},
     {"surround_depth",  "Surround level 0(quiet)-100(heavy)",   OFFSET(surround_depth),  AV_OPT_TYPE_INT, {.i64 = 0}, 0,     100, D},
     {"surround_delay",  "Surround delay in ms, usually 5-40ms", OFFSET(surround_delay),  AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, D},

     {"max_size",        "Max file size supported (in bytes). Default is 5MB. Set to 0 for no limit (not recommended)",

      OFFSET(max_size), AV_OPT_TYPE_INT, {.i64 = FF_MODPLUG_DEF_FILE_SIZE}, 0, FF_MODPLUG_MAX_FILE_SIZE, D},

     {"video_stream_expr", "Color formula",                                  OFFSET(color_eval),     AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, D},

     {"video_stream",      "Make demuxer output a video stream",             OFFSET(video_stream),   AV_OPT_TYPE_INT, {.i64 = 0},   0,   1, D},
     {"video_stream_w",    "Video stream width in char (one char = 8x8px)",  OFFSET(w),              AV_OPT_TYPE_INT, {.i64 = 30}, 20, 512, D},
     {"video_stream_h",    "Video stream height in char (one char = 8x8px)", OFFSET(h),              AV_OPT_TYPE_INT, {.i64 = 30}, 20, 512, D},
     {"video_stream_ptxt", "Print speed, tempo, order, ... in video stream", OFFSET(print_textinfo), AV_OPT_TYPE_INT, {.i64 = 1},   0,   1, D},

     {NULL},
 };
 
 #define SET_OPT_IF_REQUESTED(libopt, opt, flag) do {        \
     if (modplug->opt) {                                     \
         settings.libopt  = modplug->opt;                    \
         settings.mFlags |= flag;                            \
     }                                                       \
 } while (0)
 

 #define ADD_META_MULTIPLE_ENTRIES(entry_name, fname) do {                      \
     if (n_## entry_name ##s) {                                                 \
         unsigned i, n = 0;                                                     \
                                                                                \
         for (i = 0; i < n_## entry_name ##s; i++) {                            \
             char item_name[64] = {0};                                          \
             fname(f, i, item_name);                                            \
             if (!*item_name)                                                   \
                 continue;                                                      \
             if (n)                                                             \
                 av_dict_set(&s->metadata, #entry_name, "\n", AV_DICT_APPEND);  \
             av_dict_set(&s->metadata, #entry_name, item_name, AV_DICT_APPEND); \
             n++;                                                               \
         }                                                                      \
                                                                                \
         extra = av_asprintf(", %u/%u " #entry_name "%s",                       \
                             n, n_## entry_name ##s, n > 1 ? "s" : "");         \
         if (!extra)                                                            \
             return AVERROR(ENOMEM);                                            \
         av_dict_set(&s->metadata, "extra info", extra, AV_DICT_APPEND);        \
         av_free(extra);                                                        \
     }                                                                          \
 } while (0)
 
 static int modplug_load_metadata(AVFormatContext *s)
 {
     ModPlugContext *modplug = s->priv_data;
     ModPlugFile *f = modplug->f;
     char *extra;
     const char *name = ModPlug_GetName(f);
     const char *msg  = ModPlug_GetMessage(f);
 
     unsigned n_instruments = ModPlug_NumInstruments(f);
     unsigned n_samples     = ModPlug_NumSamples(f);
     unsigned n_patterns    = ModPlug_NumPatterns(f);
     unsigned n_channels    = ModPlug_NumChannels(f);
 
     if (name && *name) av_dict_set(&s->metadata, "name",    name, 0);
     if (msg  && *msg)  av_dict_set(&s->metadata, "message", msg,  0);
 
     extra = av_asprintf("%u pattern%s, %u channel%s",
                         n_patterns, n_patterns > 1 ? "s" : "",
                         n_channels, n_channels > 1 ? "s" : "");
     if (!extra)
         return AVERROR(ENOMEM);
     av_dict_set(&s->metadata, "extra info", extra, AV_DICT_DONT_STRDUP_VAL);
 
     ADD_META_MULTIPLE_ENTRIES(instrument, ModPlug_InstrumentName);
     ADD_META_MULTIPLE_ENTRIES(sample,     ModPlug_SampleName);
 
     return 0;
 }
 

 #define AUDIO_PKT_SIZE 512
 

 static int modplug_read_header(AVFormatContext *s)

 {
     AVStream *st;
     AVIOContext *pb = s->pb;
     ModPlug_Settings settings;
     ModPlugContext *modplug = s->priv_data;

     int64_t sz = avio_size(pb);

     if (sz < 0) {
         av_log(s, AV_LOG_WARNING, "Could not determine file size\n");
         sz = modplug->max_size;
     } else if (modplug->max_size && sz > modplug->max_size) {
         sz = modplug->max_size;

         av_log(s, AV_LOG_WARNING, "Max file size reach%s, allocating %"PRIi64"B "

                "but demuxing is likely to fail due to incomplete buffer\n",
                sz == FF_MODPLUG_DEF_FILE_SIZE ? " (see -max_size)" : "", sz);
     }

     if (modplug->color_eval) {
         int r = av_expr_parse(&modplug->expr, modplug->color_eval, var_names,
                               NULL, NULL, NULL, NULL, 0, s);
         if (r < 0)
             return r;
     }

     modplug->buf = av_malloc(modplug->max_size);
     if (!modplug->buf)
         return AVERROR(ENOMEM);
     sz = avio_read(pb, modplug->buf, sz);

 
     ModPlug_GetSettings(&settings);
     settings.mChannels       = 2;
     settings.mBits           = 16;
     settings.mFrequency      = 44100;
     settings.mResamplingMode = MODPLUG_RESAMPLE_FIR; // best quality
     settings.mLoopCount      = 0; // prevents looping forever

 
     if (modplug->noise_reduction) settings.mFlags     |= MODPLUG_ENABLE_NOISE_REDUCTION;
     SET_OPT_IF_REQUESTED(mReverbDepth,   reverb_depth,   MODPLUG_ENABLE_REVERB);
     SET_OPT_IF_REQUESTED(mReverbDelay,   reverb_delay,   MODPLUG_ENABLE_REVERB);
     SET_OPT_IF_REQUESTED(mBassAmount,    bass_amount,    MODPLUG_ENABLE_MEGABASS);
     SET_OPT_IF_REQUESTED(mBassRange,     bass_range,     MODPLUG_ENABLE_MEGABASS);
     SET_OPT_IF_REQUESTED(mSurroundDepth, surround_depth, MODPLUG_ENABLE_SURROUND);
     SET_OPT_IF_REQUESTED(mSurroundDelay, surround_delay, MODPLUG_ENABLE_SURROUND);
 
     if (modplug->reverb_depth)   settings.mReverbDepth   = modplug->reverb_depth;
     if (modplug->reverb_delay)   settings.mReverbDelay   = modplug->reverb_delay;
     if (modplug->bass_amount)    settings.mBassAmount    = modplug->bass_amount;
     if (modplug->bass_range)     settings.mBassRange     = modplug->bass_range;
     if (modplug->surround_depth) settings.mSurroundDepth = modplug->surround_depth;
     if (modplug->surround_delay) settings.mSurroundDelay = modplug->surround_delay;
 

     ModPlug_SetSettings(&settings);
 
     modplug->f = ModPlug_Load(modplug->buf, sz);
     if (!modplug->f)
         return AVERROR_INVALIDDATA;
 

     st = avformat_new_stream(s, NULL);

     if (!st)
         return AVERROR(ENOMEM);

     avpriv_set_pts_info(st, 64, 1, 1000);

     st->duration = ModPlug_GetLength(modplug->f);

     st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
     st->codecpar->codec_id    = AV_CODEC_ID_PCM_S16LE;
     st->codecpar->channels    = settings.mChannels;
     st->codecpar->sample_rate = settings.mFrequency;

     // timebase = 1/1000, 2ch 16bits 44.1kHz-> 2*2*44100
     modplug->ts_per_packet = 1000*AUDIO_PKT_SIZE / (4*44100.);
 
     if (modplug->video_stream) {

         AVStream *vst = avformat_new_stream(s, NULL);

         if (!vst)
             return AVERROR(ENOMEM);

         avpriv_set_pts_info(vst, 64, 1, 1000);

         vst->duration = st->duration;

         vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
         vst->codecpar->codec_id   = AV_CODEC_ID_XBIN;
         vst->codecpar->width      = modplug->w << 3;
         vst->codecpar->height     = modplug->h << 3;

         modplug->linesize = modplug->w * 3;
         modplug->fsize    = modplug->linesize * modplug->h;
     }
 

     return modplug_load_metadata(s);

 }
 

 static void write_text(uint8_t *dst, const char *s, int linesize, int x, int y)
 {
     int i;
     dst += y*linesize + x*3;
     for (i = 0; s[i]; i++, dst += 3) {
         dst[0] = 0x0;   // count - 1
         dst[1] = s[i];  // char
         dst[2] = 0x0f;  // background / foreground
     }
 }
 
 #define PRINT_INFO(line, name, idvalue) do {                            \
     snprintf(intbuf, sizeof(intbuf), "%.0f", var_values[idvalue]);      \
     write_text(pkt->data, name ":", modplug->linesize,  0+1, line+1);   \
     write_text(pkt->data, intbuf,   modplug->linesize, 10+1, line+1);   \
 } while (0)
 

 static int modplug_read_packet(AVFormatContext *s, AVPacket *pkt)
 {
     ModPlugContext *modplug = s->priv_data;
 

     if (modplug->video_stream) {
         modplug->video_switch ^= 1; // one video packet for one audio packet
         if (modplug->video_switch) {
             double var_values[VAR_VARS_NB];
 
             var_values[VAR_W      ] = modplug->w;
             var_values[VAR_H      ] = modplug->h;
             var_values[VAR_TIME   ] = modplug->packet_count * modplug->ts_per_packet;
             var_values[VAR_SPEED  ] = ModPlug_GetCurrentSpeed  (modplug->f);
             var_values[VAR_TEMPO  ] = ModPlug_GetCurrentTempo  (modplug->f);
             var_values[VAR_ORDER  ] = ModPlug_GetCurrentOrder  (modplug->f);
             var_values[VAR_PATTERN] = ModPlug_GetCurrentPattern(modplug->f);
             var_values[VAR_ROW    ] = ModPlug_GetCurrentRow    (modplug->f);
 
             if (av_new_packet(pkt, modplug->fsize) < 0)
                 return AVERROR(ENOMEM);
             pkt->stream_index = 1;
             memset(pkt->data, 0, modplug->fsize);
 
             if (modplug->print_textinfo) {
                 char intbuf[32];
                 PRINT_INFO(0, "speed",   VAR_SPEED);
                 PRINT_INFO(1, "tempo",   VAR_TEMPO);
                 PRINT_INFO(2, "order",   VAR_ORDER);
                 PRINT_INFO(3, "pattern", VAR_PATTERN);
                 PRINT_INFO(4, "row",     VAR_ROW);
                 PRINT_INFO(5, "ts",      VAR_TIME);
             }
 

             if (modplug->expr) {

                 int x, y;
                 for (y = 0; y < modplug->h; y++) {
                     for (x = 0; x < modplug->w; x++) {
                         double color;
                         var_values[VAR_X] = x;
                         var_values[VAR_Y] = y;

                         color = av_expr_eval(modplug->expr, var_values, NULL);

                         pkt->data[y*modplug->linesize + x*3 + 2] |= av_clip((int)color, 0, 0xf)<<4;
                     }
                 }
             }
             pkt->pts = pkt->dts = var_values[VAR_TIME];
             pkt->flags |= AV_PKT_FLAG_KEY;
             return 0;
         }
     }
 
     if (av_new_packet(pkt, AUDIO_PKT_SIZE) < 0)

         return AVERROR(ENOMEM);

     if (modplug->video_stream)
         pkt->pts = pkt->dts = modplug->packet_count++ * modplug->ts_per_packet;
 
     pkt->size = ModPlug_Read(modplug->f, pkt->data, AUDIO_PKT_SIZE);

     if (pkt->size <= 0) {

         av_packet_unref(pkt);

         return pkt->size == 0 ? AVERROR_EOF : AVERROR(EIO);

     }

     return 0;
 }
 
 static int modplug_read_close(AVFormatContext *s)
 {
     ModPlugContext *modplug = s->priv_data;
     ModPlug_Unload(modplug->f);

     av_freep(&modplug->buf);

     return 0;
 }
 
 static int modplug_read_seek(AVFormatContext *s, int stream_idx, int64_t ts, int flags)
 {

     ModPlugContext *modplug = s->priv_data;

     ModPlug_Seek(modplug->f, (int)ts);

     if (modplug->video_stream)
         modplug->packet_count = ts / modplug->ts_per_packet;

     return 0;
 }
 

 static const char modplug_extensions[] = "669,abc,amf,ams,dbm,dmf,dsm,far,it,mdl,med,mid,mod,mt2,mtm,okt,psm,ptm,s3m,stm,ult,umx,xm,itgz,itr,itz,mdgz,mdr,mdz,s3gz,s3r,s3z,xmgz,xmr,xmz";
 
 static int modplug_probe(AVProbeData *p)
 {
     if (av_match_ext(p->filename, modplug_extensions)) {
         if (p->buf_size < 16384)
             return AVPROBE_SCORE_EXTENSION/2-1;
         else
             return AVPROBE_SCORE_EXTENSION;
     }
     return 0;
 }
 

 static const AVClass modplug_class = {
     .class_name = "ModPlug demuxer",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,
 };
 

 AVInputFormat ff_libmodplug_demuxer = {
     .name           = "libmodplug",
     .long_name      = NULL_IF_CONFIG_SMALL("ModPlug demuxer"),
     .priv_data_size = sizeof(ModPlugContext),

     .read_probe     = modplug_probe,

     .read_header    = modplug_read_header,
     .read_packet    = modplug_read_packet,
     .read_close     = modplug_read_close,
     .read_seek      = modplug_read_seek,

     .extensions     = modplug_extensions,

     .priv_class     = &modplug_class,

 };