<?php
/**
 *  
 * @author  Benjamin Gillissen <hide@address.com>
 * 
 *	**************************************************************

	Copyright (C) 2009  Benjamin Gillissen
	
	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.
	
	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU General Public License for more details at:
	http://www.gnu.org/copyleft/gpl.html

 *	**************************************************************
 */

class file_cache extends file_abstract {
	
	private $CRef;
	private $expire;
	private $maxsize;
	private $match;
	private $isconn;
	
	public function __construct($CRef){
		$this->CRef = $CRef;
		$this->expire = configs::get('file_cache', $this->CRef, 'expire');
		$this->maxsize = configs::get('file_cache', $this->CRef, 'size');
		$this->match = configs::get('file_cache', $this->CRef, 'match');
		parent::__construct(configs::get('file_cache', $this->CRef, 'repo'));
		$this->isconn = $this->connect();
	}
	
	private function getbasefolder(){
		//report/report_%hash%.xml';
		$buf = split('/', $this->match);
		foreach($buf as $k => $v ){
			if ( isset($buf[$k+1]) ){ $out[] = $v; }
		}
		if ( isset($out) ){ return implode("/", $out); }
		return FALSE;
	}
	
	private function getfilematch(){
		//report/report_%hash%.xml';
		$buf = split('/', $this->match);
		$buf = $buf[count($buf)-1];
		$buf = '('.str_replace('%hash%', ')([a-z0-9]{32})(', $buf).')';	
		return $buf;
	}
	
	public function getpath($ref){ 
		return str_replace('%hash%', CORE::hash($ref), $this->match); 
	}
	
	public function cleanup(){
		if ( !$this->isconn ){ return FALSE; }
		$base = $this->getbasefolder();
		$this->chdir($base);
		$match = $this->getfilematch();
		$tots=0;
		$rfa=0;
		echo "Cleaning Cache : $this->CRef\n";
		while( FALSE !== ($file = $this->readdir('')) ){
			if ( ereg($match, $file) ){
				if ( $this->getmtime($file)+$this->expire <= time() ){
					$rfa++;
					
					$this->remove($file);
				} else {
					$tots = $tots + $this->getsize($file);
				}
			}
		}
		
		echo "$rfa files removed for expiration\n";
		errors::raise($rfa.' of the oldest files have been removed from cache '.$this->CRef, CORE_LOG_NOTICE, 'FCACHE');
		echo "Cache size : ".$tots.', limit : '.$this->maxsize."\n";
		if ( $tots >= $this->maxsize ){		
			while( FALSE !== ($file = $this->readdir('')) ){
				if ( ereg($match, $file) ){ $buf[$file] = $this->getmtime($file); }
			}
			if ( isset($buf) ){
				asort($buf, SORT_NUMERIC);
				$i=0;
				foreach($buf as $file => $mtime){
					if ( $tots >= $this->maxsize ){
						$tots = $tots - $this->getsize($file);
						$this->remove($file);	
						$i++;
					} else { break; }
				}
				echo "$i of the oldest files have been removed\n";
				errors::raise('Cache '.$this->CRef.' has exceeded his max size, '.$i.' of the oldest files have been removed', CORE_LOG_DEBUG, 'FCACHE');
			}
		}
		$this->chdir('/');
		return TRUE;
	}
	
	public function iscached($ref){
		if ( !$this->isconn ){ return FALSE; }
		$p = $this->getpath($ref);		
		return $this->isfile($p);
	}
	
	public function isexpired($ref){
		if ( !$this->isconn ){ return FALSE; }
		$p = $this->getpath($ref);		
		if ( !$this->isfile($p) ){ return TRUE; }
		if ( $this->getmtime($p)+$this->expire <= time() ){ return TRUE; }
		return FALSE;
	}
	
	public function import_file($ref, $srcfile, $repo=NULL){
		if ( !$this->isconn ){ return FALSE; }
		if ( !file_exists($srcfile) ){
			errors::raise('File to import to cache '.$this->CRef.', source does not exists localy : '.$srcfile, CORE_LOG_ERROR, 'FCACHE');
			return FALSE; 
		}
		return $this->copy($repo, $srcfile, $this->getreporef(), $this->getpath($ref));
	}
	
	public function import_data($ref, $data){
		if ( !$this->isconn ){ return FALSE; }
		if ( empty($data) ){ errors::raise('Importing empty data to cache, is it really needed?', CORE_LOG_NOTICE, 'FCACHE'); }
		return $this->writefile($this->getpath($ref), $data);
	}
	
	public function append_data($ref, $data){
		if ( !$this->isconn ){ return FALSE; }
		if ( empty($data) ){ errors::raise('Importing empty data to cache, is it really needed?', CORE_LOG_NOTICE, 'FCACHE'); }
		return $this->writefile($this->getpath($ref), $data);
	}
	
}