/*

  * Flash Compatible Streaming Format muxer

  * Copyright (c) 2000 Fabrice Bellard
  * Copyright (c) 2003 Tinic Uro

  *

  * 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 "libavcodec/put_bits.h"

 #include "avformat.h"

 #include "swf.h"

 static void put_swf_tag(AVFormatContext *s, int tag)
 {
     SWFContext *swf = s->priv_data;

     AVIOContext *pb = s->pb;

     swf->tag_pos = avio_tell(pb);

     swf->tag = tag;
     /* reserve some room for the tag */
     if (tag & TAG_LONG) {

         avio_wl16(pb, 0);
         avio_wl32(pb, 0);

     } else {

         avio_wl16(pb, 0);

     }
 }
 
 static void put_swf_end_tag(AVFormatContext *s)
 {
     SWFContext *swf = s->priv_data;

     AVIOContext *pb = s->pb;

     int64_t pos;

     int tag_len, tag;
 

     pos = avio_tell(pb);

     tag_len = pos - swf->tag_pos - 2;
     tag = swf->tag;

     avio_seek(pb, swf->tag_pos, SEEK_SET);

     if (tag & TAG_LONG) {
         tag &= ~TAG_LONG;

         avio_wl16(pb, (tag << 6) | 0x3f);
         avio_wl32(pb, tag_len - 4);

     } else {
         assert(tag_len < 0x3f);

         avio_wl16(pb, (tag << 6) | tag_len);

     }

     avio_seek(pb, pos, SEEK_SET);

 }
 
 static inline void max_nbits(int *nbits_ptr, int val)
 {
     int n;
 
     if (val == 0)
         return;
     val = abs(val);
     n = 1;
     while (val != 0) {
         n++;
         val >>= 1;
     }
     if (n > *nbits_ptr)
         *nbits_ptr = n;
 }
 

 static void put_swf_rect(AVIOContext *pb,

                          int xmin, int xmax, int ymin, int ymax)
 {
     PutBitContext p;

     uint8_t buf[256];

     int nbits, mask;
 

     init_put_bits(&p, buf, sizeof(buf));

     nbits = 0;
     max_nbits(&nbits, xmin);
     max_nbits(&nbits, xmax);
     max_nbits(&nbits, ymin);
     max_nbits(&nbits, ymax);
     mask = (1 << nbits) - 1;
 
     /* rectangle info */
     put_bits(&p, 5, nbits);
     put_bits(&p, nbits, xmin & mask);
     put_bits(&p, nbits, xmax & mask);
     put_bits(&p, nbits, ymin & mask);
     put_bits(&p, nbits, ymax & mask);

     flush_put_bits(&p);

     avio_write(pb, buf, put_bits_ptr(&p) - p.buf);

 }
 
 static void put_swf_line_edge(PutBitContext *pb, int dx, int dy)
 {
     int nbits, mask;
 
     put_bits(pb, 1, 1); /* edge */
     put_bits(pb, 1, 1); /* line select */
     nbits = 2;
     max_nbits(&nbits, dx);
     max_nbits(&nbits, dy);
 
     mask = (1 << nbits) - 1;
     put_bits(pb, 4, nbits - 2); /* 16 bits precision */
     if (dx == 0) {

         put_bits(pb, 1, 0);
         put_bits(pb, 1, 1);
         put_bits(pb, nbits, dy & mask);

     } else if (dy == 0) {

         put_bits(pb, 1, 0);
         put_bits(pb, 1, 0);
         put_bits(pb, nbits, dx & mask);

     } else {

         put_bits(pb, 1, 1);
         put_bits(pb, nbits, dx & mask);
         put_bits(pb, nbits, dy & mask);

     }
 }
 
 #define FRAC_BITS 16
 

 static void put_swf_matrix(AVIOContext *pb,

                            int a, int b, int c, int d, int tx, int ty)
 {
     PutBitContext p;

     uint8_t buf[256];

     int nbits;

     init_put_bits(&p, buf, sizeof(buf));

     put_bits(&p, 1, 1); /* a, d present */

     nbits = 1;
     max_nbits(&nbits, a);
     max_nbits(&nbits, d);
     put_bits(&p, 5, nbits); /* nb bits */
     put_bits(&p, nbits, a);
     put_bits(&p, nbits, d);

     put_bits(&p, 1, 1); /* b, c present */

     nbits = 1;
     max_nbits(&nbits, c);
     max_nbits(&nbits, b);
     put_bits(&p, 5, nbits); /* nb bits */
     put_bits(&p, nbits, c);
     put_bits(&p, nbits, b);
 
     nbits = 1;
     max_nbits(&nbits, tx);
     max_nbits(&nbits, ty);
     put_bits(&p, 5, nbits); /* nb bits */
     put_bits(&p, nbits, tx);
     put_bits(&p, nbits, ty);

 
     flush_put_bits(&p);

     avio_write(pb, buf, put_bits_ptr(&p) - p.buf);

 }
 
 static int swf_write_header(AVFormatContext *s)
 {

     SWFContext *swf = s->priv_data;

     AVIOContext *pb = s->pb;

     PutBitContext p;

     uint8_t buf1[256];

     int i, width, height, rate, rate_base;

     int version;

     swf->sound_samples = 0;
     swf->swf_frame_number = 0;
     swf->video_frame_number = 0;
 

     for(i=0;i<s->nb_streams;i++) {

         AVCodecContext *enc = s->streams[i]->codec;

         if (enc->codec_type == AVMEDIA_TYPE_AUDIO) {

             if (enc->codec_id == CODEC_ID_MP3) {
                 if (!enc->frame_size) {
                     av_log(s, AV_LOG_ERROR, "audio frame size not set\n");
                     return -1;
                 }

                 swf->audio_enc = enc;

                 swf->audio_fifo= av_fifo_alloc(AUDIO_FIFO_SIZE);

                 if (!swf->audio_fifo)
                     return AVERROR(ENOMEM);

             } else {

                 av_log(s, AV_LOG_ERROR, "SWF muxer only supports MP3\n");

                 return -1;
             }
         } else {

             if (enc->codec_id == CODEC_ID_VP6F ||
                 enc->codec_id == CODEC_ID_FLV1 ||
                 enc->codec_id == CODEC_ID_MJPEG) {

                 swf->video_enc = enc;

             } else {

                 av_log(s, AV_LOG_ERROR, "SWF muxer only supports VP6, FLV1 and MJPEG\n");

                 return -1;
             }
         }

     }
 

     if (!swf->video_enc) {

         /* currently, cannot work correctly if audio only */

         width = 320;
         height = 200;

         rate = 10;
         rate_base= 1;

     } else {

         width = swf->video_enc->width;
         height = swf->video_enc->height;
         rate = swf->video_enc->time_base.den;
         rate_base = swf->video_enc->time_base.num;

     }
 

     if (!swf->audio_enc)

         swf->samples_per_frame = (44100. * rate_base) / rate;

     else
         swf->samples_per_frame = (swf->audio_enc->sample_rate * rate_base) / rate;

     avio_write(pb, "FWS", 3);

 
     if (!strcmp("avm2", s->oformat->name))
         version = 9;

     else if (swf->video_enc && swf->video_enc->codec_id == CODEC_ID_VP6F)

         version = 8; /* version 8 and above support VP6 codec */

     else if (swf->video_enc && swf->video_enc->codec_id == CODEC_ID_FLV1)

         version = 6; /* version 6 and above support FLV1 codec */

     else

         version = 4; /* version 4 for mpeg audio support */

     avio_w8(pb, version);

     avio_wl32(pb, DUMMY_FILE_SIZE); /* dummy size

                                       (will be patched if not streamed) */

     put_swf_rect(pb, 0, width * 20, 0, height * 20);

     avio_wl16(pb, (rate * 256) / rate_base); /* frame rate */

     swf->duration_pos = avio_tell(pb);

     avio_wl16(pb, (uint16_t)(DUMMY_DURATION * (int64_t)rate / rate_base)); /* frame count */

     /* avm2/swf v9 (also v8?) files require a file attribute tag */

     if (version == 9) {

         put_swf_tag(s, TAG_FILEATTRIBUTES);

         avio_wl32(pb, 1<<3); /* set ActionScript v3/AVM2 flag */

         put_swf_end_tag(s);
     }
 

     /* define a shape with the jpeg inside */

     if (swf->video_enc && swf->video_enc->codec_id == CODEC_ID_MJPEG) {

         put_swf_tag(s, TAG_DEFINESHAPE);
 

         avio_wl16(pb, SHAPE_ID); /* ID of shape */

         /* bounding rectangle */
         put_swf_rect(pb, 0, width, 0, height);
         /* style info */

         avio_w8(pb, 1); /* one fill style */
         avio_w8(pb, 0x41); /* clipped bitmap fill */
         avio_wl16(pb, BITMAP_ID); /* bitmap ID */

         /* position of the bitmap */

         put_swf_matrix(pb, (int)(1.0 * (1 << FRAC_BITS)), 0,

                        0, (int)(1.0 * (1 << FRAC_BITS)), 0, 0);

         avio_w8(pb, 0); /* no line style */

         /* shape drawing */
         init_put_bits(&p, buf1, sizeof(buf1));
         put_bits(&p, 4, 1); /* one fill bit */
         put_bits(&p, 4, 0); /* zero line bit */

         put_bits(&p, 1, 0); /* not an edge */
         put_bits(&p, 5, FLAG_MOVETO | FLAG_SETFILL0);
         put_bits(&p, 5, 1); /* nbits */
         put_bits(&p, 1, 0); /* X */
         put_bits(&p, 1, 0); /* Y */
         put_bits(&p, 1, 1); /* set fill style 1 */

         /* draw the rectangle ! */
         put_swf_line_edge(&p, width, 0);
         put_swf_line_edge(&p, 0, height);
         put_swf_line_edge(&p, -width, 0);
         put_swf_line_edge(&p, 0, -height);

         /* end of shape */
         put_bits(&p, 1, 0); /* not an edge */
         put_bits(&p, 5, 0);

         flush_put_bits(&p);

         avio_write(pb, buf1, put_bits_ptr(&p) - p.buf);

         put_swf_end_tag(s);
     }

     if (swf->audio_enc && swf->audio_enc->codec_id == CODEC_ID_MP3) {

         int v = 0;

 
         /* start sound */

         put_swf_tag(s, TAG_STREAMHEAD2);

         switch(swf->audio_enc->sample_rate) {

         case 11025: v |= 1 << 2; break;
         case 22050: v |= 2 << 2; break;
         case 44100: v |= 3 << 2; break;

         default:
             /* not supported */

             av_log(s, AV_LOG_ERROR, "swf does not support that sample rate, choose from (44100, 22050, 11025).\n");

             return -1;
         }

         v |= 0x02; /* 16 bit playback */

         if (swf->audio_enc->channels == 2)

             v |= 0x01; /* stereo playback */

         avio_w8(s->pb, v);

         v |= 0x20; /* mp3 compressed */

         avio_w8(s->pb, v);
         avio_wl16(s->pb, swf->samples_per_frame);  /* avg samples per frame */
         avio_wl16(s->pb, 0);

         put_swf_end_tag(s);
     }
 

     avio_flush(s->pb);

     return 0;
 }
 

 static int swf_write_video(AVFormatContext *s,

                            AVCodecContext *enc, const uint8_t *buf, int size)

 {

     SWFContext *swf = s->priv_data;

     AVIOContext *pb = s->pb;

     /* Flash Player limit */

     if (swf->swf_frame_number == 16000)

         av_log(enc, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");

     if (enc->codec_id == CODEC_ID_VP6F ||
         enc->codec_id == CODEC_ID_FLV1) {

         if (swf->video_frame_number == 0) {

             /* create a new video object */
             put_swf_tag(s, TAG_VIDEOSTREAM);

             avio_wl16(pb, VIDEO_ID);

             swf->vframes_pos = avio_tell(pb);

             avio_wl16(pb, 15000); /* hard flash player limit */
             avio_wl16(pb, enc->width);
             avio_wl16(pb, enc->height);
             avio_w8(pb, 0);
             avio_w8(pb,ff_codec_get_tag(swf_codec_tags,enc->codec_id));

             put_swf_end_tag(s);
 
             /* place the video object for the first time */
             put_swf_tag(s, TAG_PLACEOBJECT2);

             avio_w8(pb, 0x36);
             avio_wl16(pb, 1);
             avio_wl16(pb, VIDEO_ID);

             put_swf_matrix(pb, 1 << FRAC_BITS, 0, 0, 1 << FRAC_BITS, 0, 0);

             avio_wl16(pb, swf->video_frame_number);

             avio_write(pb, "video", 5);

             avio_w8(pb, 0x00);

             put_swf_end_tag(s);
         } else {
             /* mark the character for update */
             put_swf_tag(s, TAG_PLACEOBJECT2);

             avio_w8(pb, 0x11);
             avio_wl16(pb, 1);
             avio_wl16(pb, swf->video_frame_number);

             put_swf_end_tag(s);
         }

         /* set video frame data */
         put_swf_tag(s, TAG_VIDEOFRAME | TAG_LONG);

         avio_wl16(pb, VIDEO_ID);
         avio_wl16(pb, swf->video_frame_number++);
         avio_write(pb, buf, size);

         put_swf_end_tag(s);

     } else if (enc->codec_id == CODEC_ID_MJPEG) {

         if (swf->swf_frame_number > 0) {
             /* remove the shape */
             put_swf_tag(s, TAG_REMOVEOBJECT);

             avio_wl16(pb, SHAPE_ID); /* shape ID */
             avio_wl16(pb, 1); /* depth */

             put_swf_end_tag(s);
 
             /* free the bitmap */
             put_swf_tag(s, TAG_FREECHARACTER);

             avio_wl16(pb, BITMAP_ID);

             put_swf_end_tag(s);
         }

         put_swf_tag(s, TAG_JPEG2 | TAG_LONG);

         avio_wl16(pb, BITMAP_ID); /* ID of the image */

         /* a dummy jpeg header seems to be required */

         avio_wb32(pb, 0xffd8ffd9);

         /* write the jpeg image */

         avio_write(pb, buf, size);

         put_swf_end_tag(s);

         /* draw the shape */

         put_swf_tag(s, TAG_PLACEOBJECT);

         avio_wl16(pb, SHAPE_ID); /* shape ID */
         avio_wl16(pb, 1); /* depth */

         put_swf_matrix(pb, 20 << FRAC_BITS, 0, 0, 20 << FRAC_BITS, 0, 0);
         put_swf_end_tag(s);
     }

     swf->swf_frame_number++;

     /* streaming sound always should be placed just before showframe tags */

     if (swf->audio_enc && av_fifo_size(swf->audio_fifo)) {
         int frame_size = av_fifo_size(swf->audio_fifo);

         put_swf_tag(s, TAG_STREAMBLOCK | TAG_LONG);

         avio_wl16(pb, swf->sound_samples);
         avio_wl16(pb, 0); // seek samples

         av_fifo_generic_read(swf->audio_fifo, pb, frame_size, (void*)avio_write);

         put_swf_end_tag(s);

         /* update FIFO */

         swf->sound_samples = 0;

     }
 

     /* output the frame */
     put_swf_tag(s, TAG_SHOWFRAME);
     put_swf_end_tag(s);

     avio_flush(s->pb);

     return 0;
 }
 

 static int swf_write_audio(AVFormatContext *s,

                            AVCodecContext *enc, uint8_t *buf, int size)

 {

     SWFContext *swf = s->priv_data;

     /* Flash Player limit */

     if (swf->swf_frame_number == 16000)

         av_log(enc, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");

     if (av_fifo_size(swf->audio_fifo) + size > AUDIO_FIFO_SIZE) {

         av_log(s, AV_LOG_ERROR, "audio fifo too small to mux audio essence\n");
         return -1;

     }
 

     av_fifo_generic_write(swf->audio_fifo, buf, size, NULL);

     swf->sound_samples += enc->frame_size;
 

     /* if audio only stream make sure we add swf frames */

     if (!swf->video_enc)

         swf_write_video(s, enc, 0, 0);

 
     return 0;
 }
 

 static int swf_write_packet(AVFormatContext *s, AVPacket *pkt)

 {

     AVCodecContext *codec = s->streams[pkt->stream_index]->codec;

     if (codec->codec_type == AVMEDIA_TYPE_AUDIO)

         return swf_write_audio(s, codec, pkt->data, pkt->size);

     else

         return swf_write_video(s, codec, pkt->data, pkt->size);

 }
 
 static int swf_write_trailer(AVFormatContext *s)
 {
     SWFContext *swf = s->priv_data;

     AVIOContext *pb = s->pb;

     AVCodecContext *enc, *video_enc;
     int file_size, i;
 
     video_enc = NULL;
     for(i=0;i<s->nb_streams;i++) {

         enc = s->streams[i]->codec;

         if (enc->codec_type == AVMEDIA_TYPE_VIDEO)

             video_enc = enc;

         else

             av_fifo_free(swf->audio_fifo);

     }
 
     put_swf_tag(s, TAG_END);
     put_swf_end_tag(s);

     avio_flush(s->pb);

 
     /* patch file size and number of frames if not streamed */

     if (s->pb->seekable && video_enc) {

         file_size = avio_tell(pb);

         avio_seek(pb, 4, SEEK_SET);

         avio_wl32(pb, file_size);

         avio_seek(pb, swf->duration_pos, SEEK_SET);

         avio_wl16(pb, swf->video_frame_number);

         avio_seek(pb, swf->vframes_pos, SEEK_SET);

         avio_wl16(pb, swf->video_frame_number);

         avio_seek(pb, file_size, SEEK_SET);

     }
     return 0;
 }
 

 #if CONFIG_SWF_MUXER

 AVOutputFormat ff_swf_muxer = {

     .name              = "swf",
     .long_name         = NULL_IF_CONFIG_SMALL("Flash format"),
     .mime_type         = "application/x-shockwave-flash",
     .extensions        = "swf",
     .priv_data_size    = sizeof(SWFContext),
     .audio_codec       = CODEC_ID_MP3,
     .video_codec       = CODEC_ID_FLV1,
     .write_header      = swf_write_header,
     .write_packet      = swf_write_packet,
     .write_trailer     = swf_write_trailer,

 };

 #endif

 #if CONFIG_AVM2_MUXER

 AVOutputFormat ff_avm2_muxer = {

     .name              = "avm2",
     .long_name         = NULL_IF_CONFIG_SMALL("Flash 9 (AVM2) format"),
     .mime_type         = "application/x-shockwave-flash",
     .priv_data_size    = sizeof(SWFContext),
     .audio_codec       = CODEC_ID_MP3,
     .video_codec       = CODEC_ID_FLV1,
     .write_header      = swf_write_header,
     .write_packet      = swf_write_packet,
     .write_trailer     = swf_write_trailer,

 };
 #endif