# include "stdio.h"
# include "assert.h"
# include "refer.h"
# include "re.h"

#ifndef D1
#define	D1 0
#endif
#if D1
#define	D(x) x
#else
#define	D(x)
#endif

static void overflo(void);

/*
 * checks list of drops for false drops;
 * uses rprog (usually "deliv") to find items
 */

void dropout(List *master, FILE *fc, int nitem, char *qitem[], char *rprog, int full)
{
	int nf;
	int	i, j, len;
	char	res[100], output[TXTLEN];
	extern int	colevel, reached;
	int need;
	re_ac *fg;

	D(fprintf(stderr, "in dropout, nf %d master %ld %ld %ld\n", nf, master->el[0], master->el[1], master->el[2]));
	nf = master->n;
	master->n = 0;
/*
 * build aho-corasick machine to check for false drops
 */
	fg = re_acinit();
	for (j = 0; j < nitem; j++) {
		char *keyw = qitem[j];
		if (!re_acadd(fg, keyw, keyw+strlen(keyw)))
			overflo();
	}
	if (!re_accomp(fg))
		overflo();
/*
 * check each candidate
 */
	for (i = 0; i < nf; i++) {
		D(fprintf(stderr, "i %d master %lo\n", i, master->el[i]));
		xseek(fc, master->el[i], 0);
		fgets(res, sizeof(res), fc);
		D(fprintf(stderr, "tag %s", res));
		if (!rdkeyfile(res, output, sizeof(output))) {
			char *s;

			D(fprintf(stderr, "not rdkeyfile try rprog %c\n", rprog? 'y': 'n'));
			if ((s = strchr(res, ';')) != 0 ||
			    (s = strchr(res, '\n')) != 0)
				*s = 0;
			if (rprog)
				corout(res, output, rprog, 0, sizeof(output));
			else
				findline(res, output, sizeof(output), indexdate);
		}
		len = strlen(output);
		D(fprintf(stderr, "item %d of %d, tag %s len %d output\n%s\n..\n", i, nf, res, len, output));
		if (len == 0)
			continue;
		need = colevel? reached: nitem;	/* min. number of matches required */
		if (re_run(fg, output, len, need) >= need) {
			D(fprintf(stderr, "fgrep found it\n"));
			applist(master, master->el[i]);
			if (master->n <= full) {
				if (soutput == 0)
					fputs(output, stdout);
				else
					strcpy(soutput, output);
			}
		}
	}
	/* free(fg); */	/* not done: space allocated statically in fgrep.c */
}

int rdkeyfile(char *res, char *output, unsigned outlen)
{
	extern FILE *fd;
	long	lp; 
	int	len;
	char *ref;

	if (fd == 0) {
		D(fprintf(stderr, "no fd in rdkeyfile\n"));
		return 0;
	}
	if (outlen)
		*output = 0;
	if ((ref = strchr(res, ';')) != 0 &&
	    sscanf(ref+1, "%ld,%d", &lp, &len) == 2) {
		fseek(fd, lp, 0);
		if (len < 0)
			len = 0;
		if (len > outlen)
			len = outlen;
		fgets(output, len, fd);
		return 1;
	}
	return 0;
}

static void overflo(void) 
{
	err("too many keywords to check (fgrep)\n");
}