/*
 * libs.c - Component libraries
 *
 * Copyright 2012 by Werner Almesberger
 *
 * 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; either version 2 of the License, or
 * (at your option) any later version.
 */

#define	_GNU_SOURCE /* for strcasecmp */
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <sys/types.h>
#include <dirent.h>

#include "util.h"
#include "libs.h"


struct entry {
	struct name *names;
	int units;
	struct entry *next;
};

static struct lib {
	const char *path;
	struct entry *comps;
	struct lib *next;
} *libs = NULL;


const char *lookup_sym(const char *name, const struct name **names, int *units)
{
	const struct lib *lib;
	const struct entry *e;

	for (lib = libs; lib; lib = lib->next)
		for (e = lib->comps; e; e = e->next)
			if (!strcasecmp(e->names->s, name)) {
				if (names)
					*names = e->names;
				if (units)
					*units = e->units;
				return lib->path;
			}
	return NULL;
}


static const char *field(const char *s, int n)
{
	while (n-- && *s) {
		while (*s && !isspace(*s))
			s++;
		while (*s && isspace(*s))
			s++;
	}
	return *s ? s : NULL;
}


static void add_name(struct entry *e, char *s)
{
	char *nl;
	struct name **p;

	nl = strchr(s, '\n');
	if (nl)
		*nl = 0;
	for (p = &e->names; *p; p = &(*p)->next);
	*p = alloc_type(struct name);
	(*p)->s = stralloc(s);
	(*p)->next = NULL;
}


void add_lib(const char *path)
{
	FILE *file;
	struct lib *lib;
	struct entry *e = NULL;
	char buf[1024]; /* @@@ */
	char *name, *spc;
	const char *s;

	file = fopen(path, "r");
	if (!file) {
		perror(path);
		exit(1);
	}

	lib = alloc_type(struct lib);
	lib->path = stralloc(path);
	lib->comps = NULL;
	lib->next = libs;
	libs = lib;

	while (fgets(buf, sizeof(buf), file)) {
		if (!strncmp(buf, "ALIAS ", 6) && e)
			add_name(e, buf+6);
		if (strncmp(buf, "DEF ", 4))
			continue;
		s = field(buf, 7);
		if (!s) {
			fprintf(stderr, "DEF record lacks units field in %s\n",
			     path);
			exit(1);
		}
		name = buf+4;
		if (*name == '~')
			name++;
		spc = strchr(name, ' ');
		if (!spc) {
			fprintf(stderr, "invalid DEF line in %s\n", path);
			exit(1);
		}
		*spc = 0;
		e = alloc_type(struct entry);
		e->names = NULL;
		add_name(e, name);
		e->units = atoi(s);
		if (!e->units) {
			fprintf(stderr, "invalid number of units in %s\n",
			    path);
			exit(1);
		}
		e->next = lib->comps;
		lib->comps = e;
	}

	fclose(file);
}


void add_libdir(const char *path)
{
	DIR *dir;
	const struct dirent *de;
	size_t len;
	char *tmp;

	dir = opendir(path);
	if (!dir) {
		perror(path);
		exit(1);
	}
	while (1) {
		de = readdir(dir);
		if (!de)
			break;
		len = strlen(de->d_name);
		if (len < 4)
			continue;
		if (strcmp(de->d_name+len-4, ".lib"))
			continue;
		if (asprintf(&tmp, "%s/%s", path, de->d_name) < 0) {
			perror("asprintf");
			exit(1);
		}
		add_lib(tmp);
	}
	closedir(dir);
}