/* This file is in the public domain. */

#include <poll.h>
#include <math.h>
#include <stdio.h>
#include <errno.h>
#include <ctype.h>
#include <fcntl.h>
#include <stdlib.h>
#include <stdarg.h>
#include <unistd.h>
#include <strings.h>
#include <sys/ioctl.h>

#include "mp4.h"

extern const char *__progname;

static const char *ifilename;
static const char *ofilename;
static MP4 *curfile;
static int prev_rate;
static int prev_chan;
static FILE *ofp;

#define Cisspace(x) isspace((unsigned char)(x))

static void handleargs(int ac, char **av)
{
 int skip;
 int errs;

 skip = 0;
 errs = 0;
 for (;ac;ac--,av++)
  { if (skip > 0)
     { skip --;
       continue;
     }
    if (**av != '-')
     { if (! ifilename)
	{ ifilename = *av;
	}
       else if (! ofilename)
	{ ofilename = *av;
	}
       else
	{ fprintf(stderr,"%s: extra argument `%s'\n",__progname,*av);
	  errs = 1;
	}
       continue;
     }
    if (0)
     {
needarg:;
       fprintf(stderr,"%s: %s needs a following argument\n",__progname,*av);
       errs = 1;
       continue;
     }
#define WANTARG() do { if (++skip >= ac) goto needarg; } while (0)
    if (! strcmp(*av,"-in"))
     { WANTARG();
       ifilename = av[skip];
       continue;
     }
    if (! strcmp(*av,"-out"))
     { WANTARG();
       ofilename = av[skip];
       continue;
     }
#undef WANTARG
    fprintf(stderr,"%s: unrecognized option `%s'\n",__progname,*av);
    errs = 1;
  }
 if (!ifilename || !ofilename)
  { fprintf(stderr,"%s: need input and output filenames\n",__progname);
    errs = 1;
  }
 if (errs) exit(1);
}

#if 0
static int compute_shift(unsigned long int m)
{
 int n;

 if (! m) abort();
 m &= ~ (m >> 1);
 if (m & (m-1)) abort();
 n = 0;
 if (m & 0xffff0000)
  { m >>= 16;
    n += 16;
  }
 if (m & 0x0000ff00)
  { m >>= 8;
    n += 8;
  }
 if (m & 0x000000f0)
  { m >>= 4;
    n += 4;
  }
 if (m & 0x0000000c)
  { m >>= 2;
    n += 2;
  }
 if (m & 0x00000002)
  { m >>= 1;
    n ++;
  }
 return(n);
}
#endif

static void init_play(void)
{
 prev_rate = -1;
 prev_chan = -1;
 ofp = fopen(ofilename,"w");
}

static void play_file(void)
{
 int i;
 int ax;
 MP4TRK *at;
 const MP4ADESC *ad;
 int nb;

 curfile = mp4_open(ifilename,0);
 mp4_scan(curfile);
 ax = -1;
 for (i=mp4_ntracks(curfile)-1;i>=0;i--)
  { switch (mp4_track_type(curfile,i))
     { default:
	  abort();
	  break;
       case MP4_TT_AUDIO:
	  ax = i;
	  break;
       case MP4_TT_VIDEO:
	  break;
     }
  }
 if (ax < 0) printf("*** no audio found\n");
 at = mp4_open_audio(curfile,ax);
 while (1)
  { ad = mp4_get_audio(at);
    if (ad->samples)
     { switch (ad->format)
	{ case MP4_AFMT_SLIN16N:
	     nb = ad->samples * ad->channels * 2;
	     fwrite(ad->data,1,nb,ofp);
	     break;
	  default:
	     abort();
	     break;
	}
     }
    else
     { mp4_close_track(at);
       break;
     }
  }
}

int main(int, char **);
int main(int ac, char **av)
{
 handleargs(ac-1,av+1);
 init_play();
 play_file();
 fclose(ofp);
 return(0);
}