#include <dirent.h>
#include <limits.h>
#include <search.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include "blaze822.h"

static int fflag;
static int nflag;
static int rflag;

struct name {
	char *id;
	char *file;
};

static void *names;

int
nameorder(const void *a, const void *b)
{
	struct name *ia = (struct name *)a;
	struct name *ib = (struct name *)b;

	return strcmp(ia->id, ib->id);
}

char *
namefind(char *id)
{
	struct name key, **result;
	key.id = id;

	if (!(result = tfind(&key, &names, nameorder)))
		return 0;

	return (*result)->file;
}

void
namescan(char *dir)
{
	DIR *fd;
	struct dirent *d;

	fd = opendir(dir);
	if (!fd)
		return;
	while ((d = readdir(fd))) {
		if (d->d_type != DT_REG && d->d_type != DT_UNKNOWN)
			continue;
		if (d->d_name[0] == '.')
			continue;

		char file[PATH_MAX];
		snprintf(file, sizeof file, "%s/%s", dir, d->d_name);

		char *e;
		if ((e = strstr(d->d_name, ":2,")))
			*e = 0;

		struct name *c = malloc(sizeof (struct name));
		c->id = strdup(d->d_name);
		c->file = strdup(file);
		tsearch(c, &names, nameorder);
	}
	closedir(fd);

	// add dir so know we scanned it already
	struct name *c = malloc(sizeof (struct name));
	c->id = c->file = strdup(dir);
	tsearch(c, &names, nameorder);
}

char *
search(char *file)
{
	char dir[PATH_MAX];
	char *e;
	if ((e = strrchr(file, '/'))) {
		snprintf(dir, sizeof dir, "%.*s", (int)(e-file), file);
		file = e+1;
	} else {
		snprintf(dir, sizeof dir, ".");
	}

	if (!namefind(dir))
		namescan(dir);

	return namefind(file);
}

/* strategy to find a Maildir file name:
   - if file exists, all good
   - try a few common different flags
   - index the containing dir, try to search for the id
   - if its in new/, try the same in cur/
 */
int
fix(char *file)
{
	int i;
	for (i = 0; *file == ' '; i++, file++)
		;

	char buf[PATH_MAX];
	char *bufptr = buf;

	if (*file == '<' || access(file, F_OK) == 0) {
		bufptr = file;
		goto ok;
	}

	char *e;
	char *sep;

	if ((e = strstr(file, ":2,"))) {
		sep = "";
		e[3] = 0;
	} else {
		sep = ":2,";
	}
	snprintf(buf, sizeof buf, "%s%s", file, sep);
	if (access(buf, F_OK) == 0) goto ok;
	snprintf(buf, sizeof buf, "%s%sS", file, sep);
	if (access(buf, F_OK) == 0) goto ok;
	snprintf(buf, sizeof buf, "%s%sRS", file, sep);
	if (access(buf, F_OK) == 0) goto ok;
	snprintf(buf, sizeof buf, "%s%sFS", file, sep);
	if (access(buf, F_OK) == 0) goto ok;

	if ((bufptr = search(file))) goto ok;

	char *ee = strrchr(file, '/');
	if (ee >= file + 3 && ee[-3] == 'n' && ee[-2] == 'e' && ee[-1] == 'w') {
		ee[-3] = 'c'; ee[-2] = 'u'; ee[-1] = 'r';
		return fix(file);
	}

	return 0;
ok:
	while(i--)
		putchar(' ');
	printf("%s\n", bufptr);
	return 1;
}

int
stdinmode()
{
	char *line = 0;
	char *l;
	size_t linelen = 0;
	ssize_t rd;
	long i = 0;

	while ((rd = getline(&line, &linelen, stdin)) != -1) {
		if (line[rd-1] == '\n')
			line[rd-1] = 0;

		if (nflag) {
			printf("%ld\n", ++i);
			break;
		}

		l = line;
		if (rflag)
			while (*l == ' ' || *l == '\t')
				l++;
		if (fflag)
			fix(l);
		else
			printf("%s\n", l);
	}

	free(line);
	return 0;
}

int
main(int argc, char *argv[])
{
	int c;
	while ((c = getopt(argc, argv, "fnr")) != -1)
		switch(c) {
		case 'f': fflag = 1; break;
		case 'n': nflag = 1; break;
		case 'r': rflag = 1; break;
		default:
			// XXX usage
			exit(1);
		}

	if (optind == argc && !isatty(0))
		return stdinmode();

	char *map = blaze822_seq_open(0);
	if (!map)
		return 1;

	int i;
	char *f;
	char *a;
	struct blaze822_seq_iter iter = { 0 };

	if (optind == argc) {
		a = ":";
		i = argc;
		goto hack;
	}
	for (i = optind; i < argc; i++) {
		a = argv[i];
hack:
		if (strchr(a, '/')) {
			printf("%s\n", a);
			continue;
		}
		while ((f = blaze822_seq_next(map, a, &iter))) {
			if (nflag) {
				printf("%ld\n", iter.line-1);
			} else {
				char *s = f;
				if (rflag)
					while (*s == ' ' || *s == '\t')
						s++;
				if (fflag)
					fix(s);
				else
					printf("%s\n", s);
			}
			free(f);
		}
	}

	return 0;
}