<?php
/**
 * Base class for simple HTML_QuickForm2 elements (not Containers)
 *
 * PHP version 5
 *
 * LICENSE:
 * 
 * Copyright (c) 2006, 2007, Alexey Borzov <avb@php.net>,
 *                           Bertrand Mansion <golgote@mamasam.com>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *    * Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *    * Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the 
 *      documentation and/or other materials provided with the distribution.
 *    * The names of the authors may not be used to endorse or promote products 
 *      derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * @category   HTML
 * @package    HTML_QuickForm2
 * @author     Alexey Borzov <avb@php.net>
 * @author     Bertrand Mansion <golgote@mamasam.com>
 * @license    http://opensource.org/licenses/bsd-license.php New BSD License
 * @version    CVS: $Id: Element.php,v 1.11 2007/04/17 13:51:25 mansion Exp $
 * @link       http://pear.php.net/package/HTML_QuickForm2
 */

/**
 * Base class for all HTML_QuickForm2 elements 
 */
require_once 'HTML/QuickForm2/Node.php';

/**
 * Abstract base class for simple QuickForm2 elements (not Containers) 
 *
 * @category   HTML
 * @package    HTML_QuickForm2
 * @author     Alexey Borzov <avb@php.net>
 * @author     Bertrand Mansion <golgote@mamasam.com>
 * @version    Release: 0.1.0
 */
abstract class HTML_QuickForm2_Element extends HTML_QuickForm2_Node
{
   /**
    * 'name' and 'id' attributes should be always present and their setting 
    * should go through setName() and setId(). 
    * @var array
    */
    protected $watchedAttributes = array('id', 'name');

    protected function onAttributeChange($name, $value = null)
    {
        if ('name' == $name) {
            if (null === $value) {
                throw new HTML_QuickForm2_InvalidArgumentException(
                    "Required attribute 'name' can not be removed"
                );
            } else {
                $this->setName($value);
            }
        } elseif ('id' == $name) {
            if (null === $value) {
                throw new HTML_QuickForm2_InvalidArgumentException(
                    "Required attribute 'id' can not be removed"
                );
            } else {
                $this->setId($value);
            }
        }
    }

    public function getName()
    {
        return $this->attributes['name'];
    }

    public function setName($name)
    {
        $this->attributes['name'] = (string)$name;
        $this->updateValue();
    }

    public function getId()
    {
        return isset($this->attributes['id'])? $this->attributes['id']: null;
    }

    public function setId($id = null)
    {
        if (is_null($id)) {
            $id = self::generateId($this->getName());
        } else {
            self::storeId($id);
        }
        $this->attributes['id'] = (string)$id;
    }

   /**
    * Generates hidden form field containing the element's value
    *
    * This is used to pass the frozen element's value if 'persistent freeze'
    * feature is on
    *
    * @return string
    */
    protected function getPersistentContent()
    {
        if (!$this->persistent || null === ($value = $this->getValue())) {
            return '';
        }
        return '<input type="hidden"' . self::getAttributesString(array(
            'name'  => $this->getName(),
            'value' => $value,
            'id'    => $this->getId()
        )) . ' />';
    }

   /**
    * Called when the element needs to update its value from form's data sources
    *
    * The default behaviour is to go through the complete list of the data 
    * sources until the non-null value is found.
    */
    protected function updateValue()
    {
        $name = $this->getName();
        foreach ($this->getDataSources() as $ds) {
            if (null !== ($value = $ds->getValue($name))) {
                $this->setValue($value);
                return;
            }
        }
    }
}
?>
