<?php if (!defined('BASEPATH')) exit('No direct script access allowed');

Class Cache_util
{
	
	function __construct($params=array())
	{
		$this->ci = & get_instance();
		if(empty($params)||!is_array($params))
		$params=array('adapter'=>$this->ci->config->item('cache_adapter'));
		$this->ci->load->driver('cache',$params); 
	
	}
	
	public function save($top_folder,$idtype,$objectid,$data)
	{
		$cacheInfo = $this->getCachInfo($top_folder,$idtype,$objectid);
		if(!is_dir($cacheInfo['cache_path']))
		{
			mkdirs($cacheInfo['cache_path']);
		}
		
		$oldPath = $this->ci->config->item('cache_path');
		$this->ci->cache->set_cache_path($cacheInfo['cache_path']);
		$this->ci->cache->save($cacheInfo['cache_id'],$data,$this->ci->config->item('biz_cache_time'));
		$this->ci->cache->set_cache_path($oldPath);
		
	}
	public function get($top_folder,$idtype,$objectid)
	{
		$cacheInfo = $this->getCachInfo($top_folder,$idtype,$objectid);
		$oldPath = $this->ci->config->item('cache_path');
		$this->ci->cache->set_cache_path($cacheInfo['cache_path']);
		$stats = $this->ci->cache->get($cacheInfo['cache_id']);
		$this->ci->cache->set_cache_path($oldPath);
		return $stats;
		
	}
	public function delete($top_folder,$idtype,$objectid)
	{
		$cacheInfo = $this->getCachInfo($top_folder,$idtype,$objectid);
		$oldPath = $this->ci->config->item('cache_path');
		$this->ci->cache->set_cache_path($cacheInfo['cache_path']);
		@$this->ci->cache->delete($cacheInfo['cache_id']);
		$this->ci->cache->set_cache_path($oldPath);
	}
	// @return array: cache_path, cache_id
	private function getCachInfo($top_folder,$idtype,$objectid)
	{
		$longid = str_pad($objectid,9, "0", STR_PAD_LEFT);
		$info['cache_path'] = APPPATH.'cache/'.$top_folder.'/'.substr($longid,0,3).'/'.substr($longid,3,3).'/';
		$info['cache_id'] = $top_folder.'_'.$idtype.'_'.$objectid;
		
		return $info;
	}
	
}
?>