<?php
/***************************************************************
 *  Copyright notice
 *
 *  (c) 2010 Marcus Krause <marcus#exp2010@t3sec.info>
 *		   Steffen Kamper <info@sk-typo3.de>
 *  All rights reserved
 *
 *  This script is part of the TYPO3 project. The TYPO3 project 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.
 *
 *  The GNU General Public License can be found at
 *  http://www.gnu.org/copyleft/gpl.html.
 *
 *  This script 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.
 *
 *  This copyright notice MUST APPEAR in all copies of the script!
 ***************************************************************/
/**
 * class.tx_em_parser_mirrorxmlpushparser.php
 *
 * Module: Extension manager - mirrors.xml push-parser
 *
 * $Id$
 *
 * @author  Marcus Krause <marcus#exp2010@t3sec.info>
 * @author  Steffen Kamper <info@sk-typo3.de>
 */


/**
 * Parser for TYPO3's mirrors.xml file.
 *
 * Depends on PHP ext/xml which should be available
 * with PHP 4+. This is the parser used in TYPO3
 * Core <= 4.3 (without the "collect all data in one
 * array" behaviour).
 * Notice: ext/xml has proven to be buggy with entities.
 * Use at least PHP 5.2.9+ and libxml2 2.7.3+!
 *
 * @author	  Marcus Krause <marcus#exp2010@t3sec.info>
 * @author	  Steffen Kamper <info@sk-typo3.de>
 *
 * @since	   2010-11-17
 * @package	 TYPO3
 * @subpackage  EM
 */
class tx_em_Parser_MirrorXmlPushParser extends tx_em_Parser_MirrorXmlAbstractParser implements SplSubject {


	/**
	 * Keeps list of attached observers.
	 *
	 * @var  array
	 */
	protected $observers = array();


	/**
	 * Class constructor.
	 *
	 * @return void
	 */
	function __construct() {
		$this->requiredPHPExt = 'xml';

		if ($this->isAvailable()) {
			$this->objXML = xml_parser_create();
			xml_set_object($this->objXML, $this);
		}
	}

	/**
	 * Method parses a mirror.xml file.
	 *
	 * @param   string  $file: GZIP stream resource
	 * @return  void
	 * @throws  em_mirrorxml_Exception  in case of XML parser errors
	 */
	public function parseXML($file) {

		if (!is_resource($this->objXML)) {
			$this->throwException('Unable to create XML parser.');
		}
		// keep original character case of XML document
		xml_parser_set_option($this->objXML, XML_OPTION_CASE_FOLDING, FALSE);
		xml_parser_set_option($this->objXML, XML_OPTION_SKIP_WHITE, FALSE);
		xml_parser_set_option($this->objXML, XML_OPTION_TARGET_ENCODING, 'utf-8');
		xml_set_element_handler($this->objXML, 'startElement', 'endElement');
		xml_set_character_data_handler($this->objXML, 'characterData');

		if (!($fp = fopen($file, "r"))) {
			$this->throwException(sprintf('Unable to open file ressource %s.', htmlspecialchars($file)));
		}
		while ($data = fread($fp, 4096)) {
			if (!xml_parse($this->objXML, $data, feof($fp))) {
				$this->throwException(sprintf('XML error %s in line %u of file ressource %s.',
					xml_error_string(xml_get_error_code($this->objXML)),
					xml_get_current_line_number($this->objXML),
					htmlspecialchars($file)));
			}
		}
		xml_parser_free($this->objXML);
	}

	/**
	 * Method is invoked when parser accesses start tag of an element.
	 *
	 * @param   ressource  $parser parser resource
	 * @param   string	 $elementName: element name at parser's current position
	 * @param   array	  $attrs: array of an element's attributes if available
	 * @return  void
	 */
	protected function startElement($parser, $elementName, $attrs) {
		switch ($elementName) {
			default:
				$this->element = $elementName;
		}
	}

	/**
	 * Method is invoked when parser accesses end tag of an element.
	 *
	 * @param   ressource  $parser parser resource
	 * @param   string	 $elementName: element name at parser's current position
	 * @return  void
	 */
	protected function endElement($parser, $elementName) {
		switch ($elementName) {
			case 'mirror':
				$this->notify();
				$this->resetProperties();
				break;
			default:
				$this->element = NULL;
		}
	}

	/**
	 * Method is invoked when parser accesses any character other than elements.
	 *
	 * @param   ressource  $parser: parser ressource
	 * @param   string	 $data: an element's value
	 * @return  void
	 */
	protected function characterData($parser, $data) {
		if (isset($this->element)) {
			switch ($this->element) {
				case 'title':
					$this->title = $data;
					break;
				case 'host':
					$this->host = $data;
					break;
				case 'path':
					$this->path = $data;
					break;
				case 'country':
					$this->country = $data;
					break;
				case 'name':
					$this->sponsorname = $data;
					break;
				case 'link':
					$this->sponsorlink = $data;
					break;
				case 'logo':
					$this->sponsorlogo = $data;
					break;
			}
		}
	}

	/**
	 * Method attaches an observer.
	 *
	 * @access  public
	 * @param   SplObserver  $observer  an observer to attach
	 * @return  void
	 * @see	 $observers, detach(), notify()
	 */
	public function attach(SplObserver $observer) {
		$this->observers[] = $observer;
	}

	/**
	 * Method detaches an attached observer
	 *
	 * @access  public
	 * @param   SplObserver  $observer  an observer to detach
	 * @return  void
	 * @see	 $observers, attach(), notify()
	 */
	public function detach(SplObserver $observer) {
		$key = array_search($observer, $this->observers, true);
		if (!($key === false)) {
			unset($this->observers[$key]);
		}
	}

	/**
	 * Method notifies attached observers.
	 *
	 * @access  public
	 * @return  void
	 * @see	 $observers, attach(), detach()
	 */
	public function notify() {
		foreach ($this->observers as $observer) {
			$observer->update($this);
		}
	}
}

if (defined('TYPO3_MODE') && isset($GLOBALS['TYPO3_CONF_VARS'][TYPO3_MODE]['XCLASS']['typo3/sysext/em/classes/parser/class.tx_em_parser_mirrorxmlpushparser.php'])) {
	include_once($GLOBALS['TYPO3_CONF_VARS'][TYPO3_MODE]['XCLASS']['typo3/sysext/em/classes/parser/class.tx_em_parser_mirrorxmlpushparser.php']);
}

?>