<?php
/**
 * 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; under version 2
 * of the License (non-upgradable).
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Copyright (c) 2008-2010 (original work) Deutsche Institut für Internationale Pädagogische Forschung (under the project TAO-TRANSFER);
 *               2009-2012 (update and modification) Public Research Centre Henri Tudor (under the project TAO-SUSTAIN & TAO-DEV);
 *
 */

/**
 * Short description of class tao_helpers_form_validators_Callback
 *
 * @access public
 * @author Joel Bout, <joel.bout@tudor.lu>
 * @package tao
 */
class tao_helpers_form_validators_Callback extends tao_helpers_form_Validator
{
    public function setOptions(array $options)
    {
        parent::setOptions($options);

        if (
            !$this->hasOption('function')
            && !(($this->hasOption('class') || $this->hasOption('object'))
                && $this->hasOption('method'))
        ) {
            throw new Exception("Please define a callback function or method");
        }

        if ($this->hasOption('message')) {
            $this->setMessage($this->getOption('message'));
        }
    }

    /**
     * Short description of method evaluate
     *
     * @access public
     * @author Joel Bout, <joel.bout@tudor.lu>
     * @param string $values
     * @return bool
     * @throws common_Exception
     * @internal param $values
     */
    public function evaluate($values)
    {
        $returnValue = (bool) false;

        if ($this->hasOption('function')) {
            $function = $this->getOption('function');
            if (function_exists($function)) {
                $callback = [$function];
            } else {
                throw new common_Exception("callback function does not exist");
            }
        } elseif ($this->hasOption('class')) {
            $class = $this->getOption('class');
            $method = $this->getOption('method');
            if (class_exists($class) && method_exists($class, $method)) {
                $callback = [$class, $method];
            } else {
                throw new common_Exception("callback method does not exist");
            }
        } elseif ($this->hasOption('object')) {
            $object = $this->getOption('object');
            $method = $this->getOption('method');
            if (method_exists($object, $method)) {
                $callback = [$object, $method];
            } else {
                throw new common_Exception("callback method does not exist");
            }
        }

        if ($this->hasOption('param')) {
            $returnValue = (bool)call_user_func($callback, $values, $this->getOption('param'));
        } else {
            $returnValue = (bool)call_user_func($callback, $values);
        }

        return (bool)$returnValue;
    }
}