<?php 
/**
 * 文件缓存
 * 
 * [WeEngine System] Copyright (c) 2013 WE7.CC
 */
defined('IN_IA') or exit('Access Denied');
/**
 * 缓存函数四个,分别用于写入,读取,删除,清空缓存。暂时采用文件缓冲,期待使用memcache或mysql内存缓冲
 */
load()->func('file');
define('CACHE_FILE_PATH', IA_ROOT . '/data/cache/');
/**
 * 获取文件缓存数据
 * @param string $key 缓存文件名称(key)
 * @param string $dir 缓存文件目录
 * @param boolean $include 获取缓存方式
 * @return mixed
 */
function cache_read($key, $dir = '', $include = true) {
	$key = str_replace(':', '@', $key);
	$key = CACHE_FILE_PATH . $key;
	if (!is_file($key)) {
		return array();
	}
	return $include ? include $key : file_get_contents($key);
}
/**
 * 设置文件缓存数据
 * @param string $key 缓存文件名称(key)
 * @param mixed $data 缓存数据
 * @param string $dir 缓存文件目录
 * @return boolean
 */
function cache_write($key, $data, $dir = '') {
	global $_W;
	if (empty($key) || !isset($data)) {
		return false;
	}
	$key = str_replace(':', '@', $key);
	if (!is_string($data)) {
		$data = "<?php \r\ndefined('IN_IA') or exit('Access Denied');\r\nreturn " . var_export($data, true) . ';';
	}
	$key = CACHE_FILE_PATH . $key;
	mkdirs(dirname($key));
	file_put_contents($key, $data);
	@chmod($key, $_W['config']['setting']['filemode']);
	return is_file($key);
}
/**
 * 删除指定缓存文件
 * @param string $key 缓存文件名称(key)
 * @param string $dir 缓存文件目录
 * @return boolean
 */
function cache_delete($key, $dir = '') {
	$cache_relation_keys = cache_relation_keys($key);
	if (is_error($cache_relation_keys)) {
		return $cache_relation_keys;
	}
	if (is_array($cache_relation_keys) && !empty($cache_relation_keys)) {
		foreach ($cache_relation_keys as $key) {
			$cache_info = cache_load($key);
			if (!empty($cache_info)) {
				$key = str_replace(':', '@', $key);
				$key = CACHE_FILE_PATH . $key;
				$result = file_delete($key);
				if (!$result) {
					return error(1, '缓存: ' . $key . ' 删除失败!');
				}
			}
		}
	}
	return true;
}

/**
 * 清空所有缓存文件
 * @param string $dir 缓存文件目录
 * @return boolean
 */
function cache_clean($dir = '') {
	return rmdirs(CACHE_FILE_PATH, true);
}