<?php
# ***** BEGIN LICENSE BLOCK *****
# This file is part of DotClear.
# Copyright (c) 2004 Olivier Meunier and contributors. All rights
# reserved.
#
# DotClear 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.
#
# DotClear 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.
#
# You should have received a copy of the GNU General Public License
# along with DotClear; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# ***** END LICENSE BLOCK *****


class antispam
{
	var $questions = array();

	function __construct()
	{
	}

	function buildQuestions()
	{
		if (dc_use_custom_questions && file_exists(DC_BASE_DIR . '/conf/questions.ini'))
		{
			$this->questions = parse_ini_file(DC_BASE_DIR . '/conf/questions.ini', true);
		}
		else
		{
			$chiffres = array(1=>'un', 'deux', 'trois', 'quatre', 'cinq', 'six', 'sept', 'huit', 'neuf',
				'dix', 'onze', 'douze', 'treize', 'quatorze', 'quinze', 'seize', 'dix-sept', 'dix-huit',
				'dix-neuf', 'vingt');

			for ($i = 1; $i < 20; $i++)
			{
				$this->questions[] = array("Si j'additionne ".$i." et ".$i.", ca fait combien ? (en chiffres)", $i+$i);
				$this->questions[] = array("Combien ca fait ".$chiffres[$i]." multiplie avec 2 ? (en chiffres)", $i*2);
				$this->questions[] = array("J'ai ".$chiffres[$i]." pommes dans mon panier, combien de pommes j'ai dans mon panier ? (en chiffres)", $i);
			}

			$fruits = array('fraise', 'pomme', 'framboise', 'cerise', 'poire');
			foreach ($fruits as $fruit)
			{
				$this->questions[] = array("Quel est le fruit qu'on trouve dans la compote de ".$fruit."s ? (en toutes lettres, au singulier)", $fruit);
				$this->questions[] = array("Quel fruit trouve-ton dans la confiture de ".$fruit."s ? (en toutes lettres, au singulier)", $fruit);
			}
		}
	}

	function generateQuestion($id)
	{
		$max = count($this->questions) - 1;
		$rand = mt_rand(0, $max);

		@session_start();
		$_SESSION['answer_' . (int)$id] = $this->questions[$rand][1];

		return $this->questions[$rand][0];
	}

	function checkAnswer($id, $answer)
	{
		@session_start();
		if (empty($_SESSION['answer_' . (int)$id]))
		{
			return false;
		}

		if (strcasecmp(trim($_SESSION['answer_' . (int)$id]), trim($answer)) == 0)
		{
			unset($_SESSION['answer_' . (int)$id]);
			return true;
		}

		return false;
	}

	// Basé sur spamtimeout
	// http://archiblog.stratic.fr/178-spamtimeout-adieu-spam-trackbacks-dotclear
	function getTimeCode($ts)
	{
		// heure actuelle (relative / billet)
		$refTime = (int) (time() - $ts);

		// encodage de l'heure (sans reveler l'heure de reference)
		return base_convert( $refTime ^ $ts, 10, 36);
	}

	function checkTimeCode($code, $ts)
	{
		// heure actuelle (relative / billet)
		$curTime = (int) (time() - $ts);

		// decodage de l'heure relative de l'URL
		$refTime = ( (int) base_convert($code, 36, 10 )) ^ $ts;

		// calcul de l'age de l'URL
		$duration = $curTime - $refTime;

		// Controle expiration URL / timeout
		if ( $duration < 2 || $duration > 900 ) {
			return false;
		}

		return true;
	}

}

?>