<?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 ratewatch extends file_abstract {
	
	private static $fmatch = '/%REF%_%HASH%.slot';
	private $lm;
	private $to;
	private $ref;

	public function __construct($limit, $timeout, $ref){
		$this->lm = $limit;
		$this->to = $timeout;
		$this->ref = $ref;
		//check for 'rate' file repo config, and happend if not present
		parent::__construct('rate');
		parent::connect();
	}
	
	private function filematch($file){ return ( ereg($this->ref, $file) AND ereg('.slot', $file) ); }
	
	public function cleanup(){
		//release expired slots.
		$d=0;
		while( FALSE !== ($file = $this->readdir('/')) ){
			if ( TRUE === $this->filematch($file) ){ 
				if ( (time()-$this->getmtime($file)) >= $this->to ){ 
					$d++;
					$this->remove('/'.$file, FALSE); 
				}
			}
		}
		if ($d != 0 ){ errors::raise($d.' slot(s) has been released for "'.$this->ref.'"', CORE_LOG_DEBUG, 'RATEWATCH'); }
	}
	
	public function gotfree_slot(){
		//how many free slot do we have ?
		$c=0;
		while( FALSE !== ($file = $this->readdir('/')) ){
			if ( TRUE === $this->filematch($file) ){ $c++; }
		}
		return ( $c < $this->lm );
	}
	
	public function add_slot($did){
		//lock a slot, by creating a file.
		if ( $this->gotfree_slot() ){
			$p = str_replace('%REF%', $this->ref, self::$fmatch);
			$p = str_replace('%HASH%', CORE::hash(NULL,5), $p);
			return $this->createfile($p, $did);
		}
	}
	
	public function fetchslots(){
		//for each slots, return the times that left before slot is released.
		while( FALSE !== ($file = $this->readdir('/')) ){
			if ( TRUE === $this->filematch($file) ){
				errors::raise('Found rate slot file : "'.$file.'" for '.$this->ref, CORE_LOG_DEBUG, 'RATE');
				$ft = $this->getmtime($file);
				$o[$ft] = $this->readfile($file);
				
			}
		}
		$l=0;
		if ( isset($o) AND @is_array($o) ){
			ksort($o);
			$k = array_keys($o);
			$i=0;
			while($i < $this->lm){
				if ( isset($k[$i]) ){
					$l++;
					$t[$i]['expire']= $this->to-(time() - $k[$i]);
					$t[$i]['desc'] 	= $o[$k[$i]];
				} else {
					$t[$i]['expire']= '';
					$t[$i]['desc'] 	= '-';
				}
				$i++;
			}
		} else {
			$i=0;
			while($i < $this->lm){
				$t[$i]['expire']= '';
				$t[$i]['desc'] 	= '-';
				$i++;
			}
		}
		errors::raise($l.' / '.$this->lm.' locked slots for '.$this->ref.'.', CORE_LOG_DEBUG, 'RATE');
		return $t;
		
	}
}