/* $Id: pltek.c,v 1.3 1993/01/23 06:16:10 mjl Exp $
   $Log: pltek.c,v $
 * Revision 1.3  1993/01/23  06:16:10  mjl
 * Formatting changes only to pltek.  plrender changes include: support for
 * polylines (even converts connected lines while reading into polylines for
 * better response), new color model support, event handler support.  New
 * events recognized allow seeking to arbitrary locations in the file (absolute
 * or relative), and backward.  Some old capabilities (no longer useful)
 * eliminated.
 *
 * Revision 1.2  1992/09/29  04:46:48  furnish
 * Massive clean up effort to remove support for garbage compilers (K&R).
 *
 * Revision 1.1  1992/05/20  21:36:00  furnish
 * Initial checkin of the whole PLPLOT project.
 *
*/

/*
*  pltek.c
*  Review a Tektronix vector file.
*  from 'scan', by Clair Nielsen, LANL.
*  Modifications by Maurice LeBrun, IFS.
*
*  This version works well with xterm and at least one vt100/tek emulator
*  I've tried.
*/

#include <stdio.h>

static long start[1000];
void describe();
#define UNSELECTED -999

/* Define graphics control characters. */
/* INDENT OFF */

#define FF   12
#define CAN  24
#define ESC  27
#define GS   29
#define US   31
#define ETX  003

/* INDENT ON */

int
main(int argc, char *argv[])
{
    FILE *fd, *fd1;
    char infile[128];
    int i, j, k, nb, nframe, iframe, ifirst, oldframe;
    int istop;
    char xtra;
    char buf[1024], lastchar;
    int dummy;
    char *ninp;
    char ibuf[128];
    char c;

    if (argc < 2) {
	describe();
	exit(1);
    }
    else
	strcpy(infile, argv[1]);

    if ((fd = fopen(infile, "r")) == NULL) {
	printf("Cannot open %s\n", argv[1]);
	exit(1);
    }
    fd1 = fopen("temp.out", "w");

/* Find out how many frames there are in file. */

    iframe = 0;
    start[0] = 0;
    for (i = 0; i < 10000; i++) {
	nb = fread(buf, 1, 1024, fd);
	if (nb <= 0)
	    break;
	ifirst = 0;
	for (j = 0; j < nb; j++) {
	    if ((lastchar = buf[j]) == '\f') {
		ifirst = j - 1;
		iframe++;
		start[iframe] = 1024 * i + ifirst + 2;
	    }
	}
    }

/* don't count a FF at the end of the file as a separate frame */

    if (lastchar == '\f')
	iframe--;

    nframe = iframe + 1;
    printf("found %d frames\n", nframe);

/* Loop until the user quits */

    iframe = 0;
    while (1) {
	oldframe = iframe;
	iframe++;
	if (iframe >= 1 && iframe <= nframe)
	    printf("Frame Number? [%d] ", iframe);
	else {
	    iframe = UNSELECTED;
	    printf("Command? ");
	}

	gets(ibuf);
	c = ibuf[0];

/* User input a frame number or a return */
/* A carriage return in response to the prompt proceeds to the next page. */

	if (isdigit(c) || c == '\0') {
#ifdef MSDOS
	    igrame = atoi(ibuf);
#else
	    sscanf(ibuf, " %d", &iframe);
#endif
	    if (iframe == UNSELECTED)
		continue;
	    if (iframe > nframe) {
		printf("  Last frame = %d.\n", nframe);
		continue;
	    }
	    if (iframe < 0) {
		iframe += oldframe;
		if (iframe < 0) {
		    printf("  Illegal frame number.\n");
		    continue;
		}
	    }
	}

/* User input a command or garbage */

	else {
	    if (c == 'h' || c == '?') {
		describe();
		continue;
	    }
	    else if (c == 'q')
		break;
	    else {
		describe();
		continue;
	    }
	}

	istop = fseek(fd, start[iframe - 1], 0);
	xtra = '\0';
	istop = 0;
	printf("%c[?38h", ESC);	/* open graphics window */
	printf("%c", GS);	/* set to vector mode */
	printf("%c%c", ESC, FF);/* clear screen */

	for (i = 0; i < 10000; i++) {
	    if (xtra != '\0') {
		fwrite(&xtra, 1, 1, stdout);
		xtra = '\0';
	    }
	    nb = fread(buf, 1, 1024, fd);
	    if (nb <= 0)
		break;
	    ifirst = 0;
	    for (j = 0; j < nb; j++) {
		if (buf[j] == '\f') {
		    fwrite(&buf[ifirst], 1, j - ifirst, stdout);
		    fflush(stdout);
		    istop = 1;
		    break;
		}
	    }
	    if (istop != 0)
		break;
	    if (buf[nb] == ESC) {
		j = j - 1;
		xtra = ESC;
	    }
	    fwrite(&buf[ifirst], 1, j - ifirst, stdout);
	}
	printf("%c%c", US, CAN);
	printf("%c%c", ESC, ETX);
	fflush(stdout);
    }
    fclose(fd);
}

/*----------------------------------------------------------------------*\
*  describe()
*
*  Print help message.
*  Note: if this message starts to exceed 512 bytes, may need to split
*  since some compilers can't handle strings that long.
\*----------------------------------------------------------------------*/
/* INDENT OFF */

void 
describe (void)
{
    fputs("\
\n\
Usage: pltek filename \n\
At the prompt, the following replies are recognized:\n\
\n\
    h	  Gives this help message.\n\
    ?     As above.\n\
    q	  Quits program.\n\
   <n>	  Goes to the specified frame number (surprise!).\n\
	  If negative, will go back the specified number of frames.\n\
 <Return> Goes to the next frame (first frame, if initial reply).\n\
\n\
", stdout);
}