/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#define SAVE_STREAMS

// simple ASF header display program by A'rpi/ESP-team
// .asf fileformat docs from http://divx.euro.ru

#include <stdio.h>
#include <stdlib.h>

typedef struct __attribute__((packed))
{
  long      biSize;          // sizeof(BITMAPINFOHEADER)
  long      biWidth;
  long      biHeight;
  short     biPlanes;        // unused
  short     biBitCount;
  long      biCompression;   // fourcc of image
  long      biSizeImage;     // size of image. For uncompressed images
                             // ( biCompression 0 or 3 ) can be zero.


  long      biXPelsPerMeter; // unused
  long      biYPelsPerMeter; // unused
  long      biClrUsed;       // valid only for palettized images.
                             // Number of colors in palette.
  long      biClrImportant;
} BITMAPINFOHEADER;

typedef struct
{
  short     wFormatTag;      // value that identifies compression format
  short     nChannels;
  long      nSamplesPerSec;
  long      nAvgBytesPerSec;
  short     nBlockAlign;     // size of a data sample
  short     wBitsPerSample;
  short     cbSize;          // size of format-specific data
} WAVEFORMATEX;

typedef struct __attribute__((packed)) {
  unsigned char      guid[16];
  unsigned long long size;
} ASF_obj_header_t;

typedef struct __attribute__((packed)) {
  ASF_obj_header_t objh;
  unsigned int     cno; // number of subchunks
  unsigned char    v1; // unknown (0x01)
  unsigned char    v2; // unknown (0x02)
} ASF_header_t;

typedef struct __attribute__((packed)) {
  unsigned char client[16]; // Client GUID
  unsigned long long file_size;
  unsigned long long creat_time; //File creation time FILETIME 8
  unsigned long long packets;    //Number of packets UINT64 8
  unsigned long long end_timestamp; //Timestamp of the end position UINT64 8
  unsigned long long duration;  //Duration of the playback UINT64 8
  unsigned long start_timestamp; //Timestamp of the start position UINT32 4
  unsigned long unk1; //Unknown, maybe reserved ( usually contains 0 ) UINT32 4
  unsigned long flags; //Unknown, maybe flags ( usually contains 2 ) UINT32 4
  unsigned long packetsize; //Size of packet, in bytes UINT32 4
  unsigned long packetsize2; //Size of packet ( confirm ) UINT32 4
  unsigned long frame_size; //Size of uncompressed video frame UINT32 4
} ASF_file_header_t;

typedef struct __attribute__((packed)) {
  unsigned char type[16]; // Stream type (audio/video) GUID 16
  unsigned char concealment[16]; // Audio error concealment type GUID 16
  unsigned long long unk1; // Unknown, maybe reserved ( usually contains 0 ) UINT64 8
  unsigned long type_size; //Total size of type-specific data UINT32 4
  unsigned long stream_size; //Size of stream-specific data UINT32 4
  unsigned short stream_no; //Stream number UINT16 2
  unsigned long unk2; //Unknown UINT32 4
} ASF_stream_header_t;

typedef struct __attribute__((packed)) {
  unsigned char streamno;
  unsigned char seq;
  unsigned long x;
  unsigned char flag;
} ASF_segmhdr_t;


ASF_header_t asfh;
ASF_obj_header_t objh;
ASF_file_header_t fileh;
ASF_stream_header_t streamh;
unsigned char buffer[8192];

int i;

static char* chunk_type(unsigned char* guid){
  switch(*((unsigned int*)guid)){
    case 0xF8699E40: return "guid_audio_stream";
    case 0xBC19EFC0: return "guid_video_stream";
    case 0x49f1a440: return "guid_audio_conceal_none";
    case 0xbfc3cd50: return "guid_audio_conceal_interleave";
    case 0x75B22630: return "guid_header";
    case 0x75b22636: return "guid_data_chunk";
    case 0x33000890: return "guid_index_chunk";
    case 0xB7DC0791: return "guid_stream_header";
    case 0xD6E229D1: return "guid_header_2_0";
    case 0x8CABDCA1: return "guid_file_header";
  }
  return NULL;
}

static void print_wave_header(WAVEFORMATEX *h){
  printf("======= WAVE Format =======\n");

  printf("Format Tag: %d (0x%X)\n", h->wFormatTag, h->wFormatTag);
  printf("Channels: %d\n", h->nChannels);
  printf("Samplerate: %ld\n", h->nSamplesPerSec);
  printf("avg byte/sec: %ld\n", h->nAvgBytesPerSec);
  printf("Block align: %d\n", h->nBlockAlign);
  printf("bits/sample: %d\n", h->wBitsPerSample);
  printf("cbSize: %d\n", h->cbSize);

  switch(h->wFormatTag){
    case 0x01:        printf("Audio in PCM format\n"); break;
    case 0x50:        printf("Audio in MPEG Layer 1/2 format\n"); break;
    case 0x55:        printf("Audio in MPEG Layer-3 format\n"); break; // ACM
    case 0x02:        printf("Audio in MS ADPCM format\n"); break;  // ACM
    case 0x11:        printf("Audio in IMA ADPCM format\n"); break; // ACM
    case 0x31:
    case 0x32:        printf("Audio in MS GSM 6.10 format\n"); break; // ACM
    case 0x160:
    case 0x161:       printf("Audio in DivX WMA format\n"); break; // ACM
    default:          printf("Audio in UNKNOWN (id=0x%X) format\n", h->wFormatTag);
  }

  printf("===========================\n");
}

static void print_video_header(BITMAPINFOHEADER *h){
  printf("======= VIDEO Format ======\n");
  printf("  biSize %ld\n", h->biSize);
  printf("  biWidth %ld\n", h->biWidth);
  printf("  biHeight %ld\n", h->biHeight);
  printf("  biPlanes %d\n", h->biPlanes);
  printf("  biBitCount %d\n", h->biBitCount);
  printf("  biCompression %ld='%.4s'\n", h->biCompression, &h->biCompression);
  printf("  biSizeImage %ld\n", h->biSizeImage);
  printf("===========================\n");
}

FILE* streams[128];

int main(int argc, char* argv[]){
  FILE *f = fopen(argc > 1 ? argv[1] : "Alice Deejay - Back In My Life.asf", "rb");

  if(!f){
    printf("file not found\n");
    exit(1);
  }

  //printf("sizeof=%d\n", sizeof(objh));
  //printf("sizeof=%d\n", sizeof(asfh));

  fread(&asfh, sizeof(asfh), 1, f); // header obj
  //for(i = 0; i < 16; i++)
  //  printf("%02X ", asfh.objh.guid[i]);
  printf("[%s] %d  (subchunks: %d)\n", chunk_type(asfh.objh.guid),
         (int) asfh.objh.size, asfh.cno);

  while(fread(&objh, sizeof(objh), 1, f) > 0){
    int pos = ftell(f);
    //for(i = 0; i < 16; i++)
    //  printf("%02X ", objh.guid[i]);
    printf("0x%08X  [%s] %d\n", pos-sizeof(objh), chunk_type(objh.guid),
           (int) objh.size);
    switch(*((unsigned int*)&objh.guid)){
      case 0xB7DC0791: // guid_stream_header
        fread(&streamh, sizeof(streamh), 1, f);
        printf("stream type: %s\n", chunk_type(streamh.type));
        printf("stream concealment: %s\n", chunk_type(streamh.concealment));
        printf("type: %d bytes,  stream: %d bytes  ID: %d\n",
               (int)streamh.type_size, (int)streamh.stream_size,
               (int)streamh.stream_no);
        printf("FILEPOS=0x%lX\n", ftell(f));
        // type-specific data:
        fread(buffer,streamh.type_size,1,f);
        switch(*((unsigned int*)&streamh.type)){
        case 0xF8699E40:  // guid_audio_stream
          print_wave_header((WAVEFORMATEX*)buffer);
          break;
        case 0xBC19EFC0:  // guid_video_stream
          print_video_header((BITMAPINFOHEADER*)&buffer[4 + 4 + 1 + 2]);
          break;
        }
        // stream-specific data:
        fread(buffer, streamh.stream_size, 1, f);
        break;
      //case 0xD6E229D1:
      //  return "guid_header_2_0";
      case 0x8CABDCA1: // guid_file_header
        fread(&fileh, sizeof(fileh), 1, f);
        printf("packets: %d  flags: %d  pack_size: %d  frame_size: %d\n",
               (int)fileh.packets, (int)fileh.flags, (int)fileh.packetsize,
               (int)fileh.frame_size);
        break;
      case 0x75b22636: // guid_data_chunk
        { int endp = pos + objh.size - sizeof(objh);
          unsigned char* packet = malloc((int)fileh.packetsize);
          int fpos;
          fseek(f, 26, SEEK_CUR);
          while((fpos = ftell(f)) < endp){
            fread(packet, (int)fileh.packetsize, 1, f);
            if(packet[0] == 0x82){
              unsigned char flags = packet[3];
              unsigned char* p = &packet[5];
              unsigned long time;
              unsigned short duration;
              int segs = 1;
              int seg;
              int padding=0;
              if(flags & 8){
                padding = p[0];
                ++p;
              } else
              if(flags & 16){
                padding = p[0] | (p[1] << 8);
                p += 2;
              }
              time = *((unsigned long*)p);
              p += 4;
              duration = *((unsigned short*)p);
              p += 2;
              if(flags & 1){
                segs = p[0] - 0x80;
                ++p;
              }
              printf("%08X:  flag=%02X  segs=%d  pad=%d  time=%ld  dur=%d\n",
                     fpos, flags, segs, padding, time, duration);
              for(seg = 0; seg < segs; seg++){
                ASF_segmhdr_t* sh = (ASF_segmhdr_t*)p;
                int len = 0;
                p += sizeof(ASF_segmhdr_t);
                if(sh->flag & 8) p+=8;// else
                if(sh->flag & 1) ++p;
                if(flags & 1){
                  len = *((unsigned short*)p);
                  p += 2;
                }
                printf("  seg #%d: streamno=%d  seq=%d  flag=%02X  len=%d\n",
                       seg, sh->streamno&0x7F, sh->seq, sh->flag, len);
  #ifdef SAVE_STREAMS
                if(!streams[sh->streamno & 0x7F]){
                  char name[256];
                  snprintf(name, 256, "stream%02X.dat", sh->streamno & 0x7F);
                  streams[sh->streamno & 0x7F] = fopen(name, "wb");
                }
                fwrite(p, len, 1, streams[sh->streamno & 0x7F]);
  #endif
                p += len;
              }
            } else
              printf("%08X:  UNKNOWN  %02X %02X %02X %02X %02X...\n", fpos,
                     packet[0], packet[1], packet[2], packet[3], packet[4]);
          }
        }
        break;

        //case 0x33000890:
        //  return "guid_index_chunk";

    }
    fseek(f, pos + objh.size - sizeof(objh), SEEK_SET);
  }

  return 0;
}
