/*
   decode_tm6000.c - decode multiplexed format from TM5600/TM6000 USB

   Copyright (C) 2007 Mauro Carvalho Chehab <mchehab@infradead.org>

   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 version 2.

   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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
#include "../lib/v4l2_driver.h"
#include <stdio.h>
#include <string.h>
#include <argp.h>
#include <unistd.h>

const char *argp_program_version="decode_tm6000 version 0.0.1";
const char *argp_program_bug_address="Mauro Carvalho Chehab <mchehab@infradead.org>";
const char doc[]="Decodes tm6000 proprietary format streams";
const struct argp_option options[] = {
	{"verbose",	'v',	0,	0,	"enables debug messages", 0},
	{"device",	'd',	"DEV",	0,	"uses device for reading", 0},
	{"output",	'o',	"FILE",	0,	"outputs raw stream to a file", 0},
	{"input",	'i',	"FILE",	0,	"parses a file, instead of a device", 0},
	{"audio",	'a',	0,	0,	"outputs audio on stdout", 0},
	{"read",	'r',	0,	0,	"use read() instead of mmap method", 0},
	{ 0, 0, 0, 0, 0, 0 }
};

static int debug=0, audio=0, use_mmap=1;
static char *devname="/dev/video0";
static char *filename=NULL;
static enum {
	NORMAL,
	INPUT,
	OUTPUT
} mode = NORMAL;

static FILE *fout;

//const char args_doc[]="ARG1 ARG2";

static error_t parse_opt (int key, char *arg, struct argp_state *state)
{
	switch (key) {
	case 'a':
		audio++;
		break;
	case 'r':
		use_mmap=0;
		break;
	case 'v':
		debug++;
		break;
	case 'd':
		devname=arg;
		break;
	case 'i':
	case 'o':
		if (mode!=NORMAL) {
			argp_error(state,"You can't use input/output options simultaneously.\n");
			break;
		}
		if (key=='i')
			mode=INPUT;
		else
			mode=OUTPUT;

		filename=arg;
		break;
	default:
		return ARGP_ERR_UNKNOWN;
	}
	return 0;
}

static struct argp argp = {
	.options=options,
	.parser=parse_opt,
	.args_doc=NULL,
	.doc=doc,
};

#define TM6000_URB_MSG_LEN 180
enum {
	TM6000_URB_MSG_VIDEO=1,
	TM6000_URB_MSG_AUDIO,
	TM6000_URB_MSG_VBI,
	TM6000_URB_MSG_PTS,
	TM6000_URB_MSG_ERR,
};

const char *tm6000_msg_type[]= {
	"unknown(0)",	//0
	"video",	//1
	"audio",	//2
	"vbi",		//3
	"pts",		//4
	"err",		//5
	"unknown(6)",	//6
	"unknown(7)",	//7
};

#define dprintf(fmt,arg...) \
	if (debug) fprintf(stderr, fmt, ##arg)

int recebe_buffer (struct v4l2_buffer *v4l2_buf, struct v4l2_t_buf *buf)
{
	fwrite (buf->start,buf->length,1,fout);
	return 0;
}


int read_mmap(struct v4l2_driver *drv)
{
	double freq;

	freq=193.25 * 1000 * 1000;
	v4l2_getset_freq (drv,V4L2_SET, &freq);

	printf("Preparing for frames...\n");
	fflush (stdout);
	sleep(1);

	v4l2_mmap_bufs(drv, 2);

	v4l2_start_streaming(drv);

	printf("Waiting for frames...\n");
	while (1) {
		fd_set fds;
		struct timeval tv;
		int r;

		FD_ZERO (&fds);
		FD_SET (drv->fd, &fds);

		/* Timeout. */
		tv.tv_sec = 2;
		tv.tv_usec = 0;

		r = select (drv->fd + 1, &fds, NULL, NULL, &tv);
		if (-1 == r) {
			if (EINTR == errno)

			perror ("select");
			return errno;
		}

		if (0 == r) {
			fprintf (stderr, "select timeout\n");
			return errno;
		}

		if (v4l2_rcvbuf(drv, recebe_buffer))
			break;
	}
	return 0;
}


int main (int argc, char*argv[])
{
	FILE *fp;
	unsigned char c, buf[TM6000_URB_MSG_LEN], img[720*2*480];
	unsigned int  cmd, cpysize, pktsize, size, field, block, line, pos=0;
	unsigned long header=0;
	int           linesize=720*2,skip=0;
	struct v4l2_format fmt;
	struct v4l2_driver drv;

	argp_parse (&argp, argc, argv, 0, 0, 0);

	if (mode!=INPUT) {
		if (v4l2_open (devname, 1,&drv)<0) {
			perror ("Error opening dev");
			return -1;
		}
		fp=fdopen(drv.fd,"r");
		if (!fp) {
			perror("error associating dev");
			return -1;
		}

		memset (&fmt,0,sizeof(fmt));

		uint32_t pixelformat=V4L2_PIX_FMT_TM6000;

		if (v4l2_gettryset_fmt_cap (&drv,V4L2_SET,&fmt, 720, 480,
						pixelformat,V4L2_FIELD_ANY)) {
			perror("set_input to tm6000 raw format");
			return -1;
		}
	}

	if (mode==INPUT) {
		fp=fopen(filename,"r");
		if (!fp) {
			perror ("error opening a file for parsing");
			return -1;
		}
		dprintf("file %s opened for parsing\n",filename);
	}

	if (mode==OUTPUT) {
		char outbuf[2<<18];

		fout=fopen(filename,"w");
		if (!fout) {
			perror ("error opening a file to write");
			return -1;
		}
		dprintf("file %s opened for output\n",filename);

		if (use_mmap) {
			return (read_mmap(&drv));
		}

		do {
			size=fread(outbuf,1, sizeof(outbuf), fp);
			if (!size) {
				fclose (fp);
				return 0;
			}
			dprintf("writing %d bytes\n",size);
			fwrite(outbuf,1, size,fout);
//			fflush(fout);
		} while (1);
	}

	while (1) {
		skip=0;
		header=0;
		do {
			c=fgetc(fp);
			header=(header>>8)&0xffffff;
			header=header|(c<<24);
			skip++;
		} while ( (((header>>24)&0xff) != 0x47) );

		/* split the header fields */
		size  = (((header & 0x7e)<<1) -1) * 4;
		block = (header>>7) & 0xf;
		field = (header>>11) & 0x1;
		line  = (header>>12) & 0x1ff;
		cmd   = (header>>21) & 0x7;

		/* Read the remaining buffer */
		fread((char *)buf,sizeof(buf), 1, fp);

		/* FIXME: Mounts the image as field0+field1
			* It should, instead, check if the user selected
			* entrelaced or non-entrelaced mode
			*/
		pos=((line<<1)+field)*linesize+
					block*TM6000_URB_MSG_LEN;

			/* Prints debug info */
		dprintf("0x%08x (skip %d), %s size=%d, num=%d,line=%d, field=%d\n",
				(unsigned int)header, skip,
				 tm6000_msg_type[cmd],
				 size, block, line, field);

		/* Don't allow to write out of the buffer */
		if (pos+sizeof(buf) > sizeof(img))
			cmd = TM6000_URB_MSG_ERR;

		/* handles each different URB message */
		switch(cmd) {
		case TM6000_URB_MSG_VIDEO:
			/* Fills video buffer */
			memcpy(buf,&img[pos],sizeof(buf));
		case TM6000_URB_MSG_AUDIO:
			if (audio)
				fwrite(buf,sizeof(buf),1,stdout);
//		case TM6000_URB_MSG_VBI:
//		case TM6000_URB_MSG_PTS:
		break;
		}
	}
	fclose(fp);
	return 0;
}