/*
 *				**** EMBED_PS ****
 *
 * This program builds a C program that will output a postscript file
 * The name of the file to be read is passed.  It must end with .ps
 * The output will be of the same name, but suffixed with a .c
 * instead of a .ps
 *
 * Author:	Bill Pringle (wrp@ivy.unisys.com)
 *
 * Change History:
 *
 * 1.0		Initial release
 *
 * 1.1		Added command options: help option & specify name of function
 *
 */

#include <stdio.h>
#include <string.h>

#ifdef __MSDOS__
#define	DIRSLASH	'\\'
#else
#define	DIRSLASH	'/'
#endif

void	embed_ps(char *, char *, FILE *, FILE *);
void	prologue(char *, char *, FILE *);
void	do_help(char *);
void	do_usage(char *);

main(int argc, char **argv)
{
	char	*Prog;					/* name of program */
	char	*dir;					/* directory name */
	char	buf[BUFSIZ];			/* input buffer */
	FILE	*infp;					/* input file pointer */
	FILE	*ofp;					/* output file pointer */
	int		len;					/* length */
	char	*fname;					/* name of function */
	char	*p;						/* pointer for parsing */

	if ((Prog = strrchr(argv[0],DIRSLASH)) == NULL)
	{	/* no slash, use current directory */
		Prog = argv[0];				/* program name */
		dir = "./";					/* directory name */
	} else
	{
		*Prog++ = '\0';				/* program name */
		dir = argv[0];				/* directory name */
	}

#ifdef __MSDOS__
	if ((p = strrchr(Prog,'.')) != NULL) *p = '\0';
	for (p = Prog; *p != '\0'; p++) if (isupper(*p)) *p = tolower(*p);
#endif

	if (argc == 1)
	{		/* no arguments, display help message and quit */
		do_help(Prog);
		return 0;
	}

	fname = "prologue_ps";			/* default name of function */

	for (argc--, argv++; argc > 0; argc--, argv++)
	{		/* process argument(s) */
		if (argv[0][0] == '-')
		{		/* command option - process it */
			switch(argv[0][1])
			{		/* process option itself */
				case 'h':		/* help */
					do_help(Prog);
					return 0;		/* terminate */

				case 'n':		/* name of function */
					if (argv[0][2] == '\0')
					{		/* function name is next argument */
						argc--; argv++;		/* shift option out */
						fname = argv[0];		/* name of function */
					} else fname = argv[0] + 2;	/* name of function */
					break;

				default:		/* bad option */
					fprintf(stderr,"%s: Invalid option (%s)\n", Prog, argv[0]);
					do_usage(Prog);
					return 1;		/* bad option */
			}
		} else
		{		/* input file name given */
			if ((infp = fopen(argv[0],"r")) == NULL)
			{	/* not found - try execute directory */
				strcpy(buf,dir);		/* directory */
				len = strlen(buf);		/* length of name */
				buf[len] = DIRSLASH;	/* add directory slash */
				strcpy(buf+len+1,argv[0]); /* add file name */
				if ((infp = fopen(buf,"r")) == NULL)
				{	/* still not found - give up */
					fprintf(stderr,"%s: Can't open file %s\n",
						Prog, argv[0]);
					continue;
				}
			}

			strcpy(buf,argv[0]);		/* get file name */
			len = strlen(buf);			/* length of name */
			if (strcmp(buf + len - 3, ".ps"))
			{	/* file doesn't end in .ps */
				fprintf(stderr,"%s: File (%s) must end in '.ps'\n",
					Prog, argv[0]);
				fclose(infp);				/* close input file */
				continue;
			}

			strcpy(buf + len - 3, ".c"); /* c file name */

			if ((ofp = fopen(buf,"w")) == NULL)
			{	/* can't open output file */
				fprintf(stderr,"%s: Can't open output file %s.\n",
					Prog, buf);
			}
			embed_ps(Prog,fname,infp,ofp);
		}	/* end of processing argument */
	}
	return 0;
}

void
embed_ps(char *Prog,char *fname, FILE *ifp, FILE *ofp)
{		/* convert PS file ifp into C function fname to file ofp */
	int		c;					/* character read */

	/* output prologue */
	prologue(Prog, fname, ofp);

	fprintf(ofp,"fprintf(ofp,\"");

	while ((c = fgetc(ifp)) != EOF) switch(c)
	{	/* check for output character */
		case '\\':	fprintf(ofp,"\\\\"); break;
		case '"':	fprintf(ofp,"\\\""); break;
		case '%':	fprintf(ofp,"%%%%"); break;
		case '\n':	fprintf(ofp,"\\n\");\nfprintf(ofp,\""); break;
		default:	fputc(c,ofp);
	}
	fprintf(ofp,"\\n\");\n}\n");
}

void
prologue(char *Prog, char *fname, FILE *ofp)
{
	fprintf(ofp,"/*\t\t\t\t**** %s ****\n", fname);
	fprintf(ofp,"/* this program was automatically generated by %s. */\n", Prog);
	fprintf(ofp,"/* you should probably not edit it */\n");
	fprintf(ofp,"#include <stdio.h>\n");
	fprintf(ofp,"void\n%s(FILE *ofp)\n{\n", fname);
}

void
do_help(char *Prog)
{		/* display help message for user */
	int		i;		/* loop variable */
	char *msg[] = {
"This program reads a PostScript program and produces a C program that will\n",
"\tcreate a duplicate of the original file.\n",
"\nThe user may specify a function name (the default is prologue_ps)\n",
"\nThe program assumes that the input file has a suffix of `.ps'.\n",
"The output file will have the suffix changed to `.c'\n",
"\nFor example, the command:\n",
"\n",
"\t%s -f foo bar.ps\n",
"\nwill read the PostScript file bar.ps and create a C source file bar.c\n",
"which will contain a function `foo' which, when called, will output the\n",
"contents of the original file.\n",
NULL};

	for (i=0; msg[i] != NULL; i++) fprintf(stderr,msg[i],Prog);
	do_usage(Prog);
}

void
do_usage(char *Prog)
{		/* output a usage message */
	int		i;		/* loop index variable */
	char	*msg[] = {
"Usage:\t%s [-f fname] pfile ...\n",
"-OR- for help, type:\n"
"\t%s -h\n",
"Where:\n"
"\tfname\tis the name of the C function to be created.\n",
"\tpfile\tis the name of the PostScript input file with a suffix of .ps\n",
NULL};

	for (i=0; msg[i] != NULL; i++) fprintf(stderr,msg[i],Prog);
}