#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include <strings.h>
#include <theora/codec.h>
#include <theora/theoraenc.h>

extern const char *__progname;

static unsigned char frame[640*480*2];
static unsigned char planar_y[640*480];
static unsigned char planar_cb[320*480];
static unsigned char planar_cr[320*480];

static void planarize(void)
{
 unsigned char *ip;
 unsigned char *op_y;
 unsigned char *op_cb;
 unsigned char *op_cr;
 int y;
 int x;

 ip = &frame[0];
 op_y = &planar_y[0];
 op_cb = &planar_cb[0];
 op_cr = &planar_cr[0];
 for (y=480;y>0;y--)
  { for (x=640;x>0;x-=2)
     { *op_y++ = ip[0];
       *op_y++ = ip[2];
       *op_cb++ = ip[1];
       *op_cr++ = ip[3];
       ip += 4;
     }
  }
}

static int rd(void *data, int len)
{
 int r;
 unsigned char *dp;
 int l;

 dp = data;
 l = len;
 while (l > 0)
  { r = read(0,dp,l);
    if (r < 0)
     { fprintf(stderr,"%s: input read: %s\n",__progname,strerror(errno));
       exit(1);
     }
    if (r == 0) return(0);
    if (r > l) abort();
    dp += r;
    l -= r;
  }
 return(1);
}

static void print_pkt(const ogg_packet *p)
{
#if 0
 int i;

 fprintf(stderr,"packet: bytes %ld bos %ld eos %ld gpos %lld pno %lld\n",
	(long int)p->bytes, (long int)p->b_o_s, (long int)p->e_o_s,
	(long long int)p->granulepos, (long long int)p->packetno );
 fprintf(stderr,"packet data:");
 for (i=0;i<p->bytes;i++) fprintf(stderr," %02x",p->packet[i]);
 fprintf(stderr,"\n");
#endif
 printf("%ld %ld %ld %lld %lld\n",
	(long int)p->bytes, (long int)p->b_o_s, (long int)p->e_o_s,
	(long long int)p->granulepos, (long long int)p->packetno );
 fwrite(p->packet,1,p->bytes,stdout);
}

int main(void)
{
 th_info thi;
 th_enc_ctx *thec;
 th_comment comm;
 ogg_packet pkt;
 th_ycbcr_buffer ibuf;
 int e;

 void load_ibuf(void)
  { ibuf[0].width = 640;
    ibuf[0].height = 480;
    ibuf[0].stride = 640;
    ibuf[0].data = &planar_y[0];
    ibuf[1].width = 320;
    ibuf[1].height = 480;
    ibuf[1].stride = 320;
    ibuf[1].data = &planar_cb[0];
    ibuf[2].width = 320;
    ibuf[2].height = 480;
    ibuf[2].stride = 320;
    ibuf[2].data = &planar_cr[0];
  }

 void send_ibuf(void)
  { int e;
    /* XXX th_ycbcr_buffer is an array (!), hence no & */
    e = th_encode_ycbcr_in(thec,ibuf);
    if (e != 0)
     { fprintf(stderr,"th_encode_ycbcr_in error %d\n",e);
       exit(1);
     }
  }

 void drain_output(void)
  { int e;
    while (1)
     { e = th_encode_packetout(thec,0,&pkt);
       if (e == 0) break;
       if (e > 0)
	{ print_pkt(&pkt);
	}
       else
	{ fprintf(stderr,"th_encode_packetout error %d\n",e);
	  exit(1);
	}
     }
    fflush(0);
  }

 thi.version_major = 1; // XXX undocumented
 thi.version_minor = 1; // XXX undocumented
 thi.version_subminor = 1; // XXX undocumented
 thi.frame_width = 640;
 thi.frame_height = 480;
 thi.pic_width = 640;
 thi.pic_height = 480;
 thi.pic_x = 0;
 thi.pic_y = 0;
 /*
  * The documentation says of these "If either is 0, the frame rate is
  *  undefined.".  What it doesn't say is that the encoder will happily
  *  accept such settings, encode them in the resulting stream, and the
  *  decoder will then barf with TH_EBADHEADER.
  */
 thi.fps_numerator = 10;
 thi.fps_denominator = 1;
 thi.aspect_numerator = 1;
 thi.aspect_denominator = 1;
 thi.colorspace = TH_CS_ITU_REC_470M;
 thi.pixel_fmt = TH_PF_422;
 thi.target_bitrate = 0;
 thi.quality = 0;
 thi.keyframe_granule_shift = 6;
 thec = th_encode_alloc(&thi);
 // th_encode_ctl(...) none needed
 comm.user_comments = 0;
 comm.comment_lengths = 0;
 comm.comments = 0;
 comm.vendor = 0;
 while (1)
  { e = th_encode_flushheader(thec,&comm,&pkt);
    if (e == 0) break;
    if (e > 0)
     { print_pkt(&pkt);
     }
    else
     { fprintf(stderr,"th_encode_flushheader error %d\n",e);
       exit(1);
     }
  }
 if (! rd(&frame[0],640*480*2)) exit(0);
 planarize();
 while (rd(&frame[0],640*480*2))
  { fprintf(stderr,"frame in\n");
    load_ibuf();
    send_ibuf();
    drain_output();
    planarize();
  }
 fprintf(stderr,"final frame in\n");
 load_ibuf();
 send_ibuf();
 drain_output();
 th_encode_free(thec);
 printf(".");
 return(0);
}