/*
 * Copyright © 2011 Intel Corporation
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that copyright
 * notice and this permission notice appear in supporting documentation, and
 * that the name of the copyright holders not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  The copyright holders make no representations
 * about the suitability of this software for any purpose.  It is provided "as
 * is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 */

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

#include "configparser.h"

static int
handle_key(const struct config_key *key, const char *value)
{
	char *end, *s;
	int i, len;
	
	switch (key->type) {
	case CONFIG_KEY_INTEGER:
		i = strtol(value, &end, 0);
		if (*end != '\n') {
			fprintf(stderr, "invalid integer: %s\n", value);
			return -1;
		}
		*(int *)key->data = i;
		return 0;

	case CONFIG_KEY_STRING:
		len = strlen(value);
		s = malloc(len);
		if (s == NULL)
			return -1;
		memcpy(s, value, len - 1);
		s[len - 1] = '\0';
		*(char **)key->data = s;
		return 0;

	case CONFIG_KEY_BOOLEAN:
		if (strcmp(value, "false\n") == 0)
			*(int *)key->data = 0;
		else if (strcmp(value, "true\n") == 0)
			*(int *)key->data = 1;
		else {
			fprintf(stderr, "invalid bool: %s\n", value);
			return -1;
		}
		return 0;

	default:
		assert(0);
		break;
	}
}

int
parse_config_file(const char *path,
		  const struct config_section *sections, int num_sections,
		  void *data)
{
	FILE *fp;
	char line[512], *p;
	const struct config_section *current = NULL;
	int i;

	fp = fopen(path, "r");
	if (fp == NULL) {
		fprintf(stderr, "couldn't open %s\n", path);
		return -1;
	}

	while (fgets(line, sizeof line, fp)) {
		if (line[0] == '#' || line[0] == '\n') {
			continue;
		} if (line[0] == '[') {
			p = strchr(&line[1], ']');
			if (!p || p[1] != '\n') {
				fprintf(stderr, "malformed "
					"section header: %s\n", line);
				fclose(fp);
				return -1;
			}
			if (current && current->done)
				current->done(data);
			p[0] = '\0';
			for (i = 0; i < num_sections; i++) {
				if (strcmp(sections[i].name, &line[1]) == 0) {
					current = &sections[i];
					break;
				}
			}
			if (i == num_sections)
				current = NULL;
		} else if (p = strchr(line, '='), p != NULL) {
			if (current == NULL)
				continue;
			p[0] = '\0';
			for (i = 0; i < current->num_keys; i++) {
				if (strcmp(current->keys[i].name, line) == 0) {
					if (handle_key(&current->keys[i], &p[1]) < 0) {
						fclose(fp);
						return -1;
					}
					break;
				}
			}
		} else {
			fprintf(stderr, "malformed config line: %s\n", line);
			fclose(fp);
			return -1;
		}
	}

	if (current && current->done)
		current->done(data);

	fclose(fp);

	return 0;
}

char *
config_file_path(const char *name)
{
	const char dotconf[] = "/.config/";
	const char *config_dir;
	const char *home_dir;
	char *path;
	size_t size;

	config_dir = getenv("XDG_CONFIG_HOME");
	if (!config_dir) {
		home_dir = getenv("HOME");
		if (!home_dir) {
			fprintf(stderr, "HOME is not set, using cwd.\n");
			return strdup(name);
		}

		size = strlen(home_dir) + sizeof dotconf + strlen(name);
		path = malloc(size);
		if (!path)
			return NULL;

		snprintf(path, size, "%s%s%s", home_dir, dotconf, name);
		return path;
	}

	size = strlen(config_dir) + 1 + strlen(name) + 1;
	path = malloc(size);
	if (!path)
		return NULL;

	snprintf(path, size, "%s/%s", config_dir, name);
	return path;
}