<?php
/*
 * Gallery - a web based photo album viewer and editor
 * Copyright (C) 2000-2008 Bharat Mediratta
 *
 * 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.
 *
 * 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.
 */

/**
 * RewriteParser class.  Parsers are stored in modules/rewrite/classes/parsers/<parserId> and
 * require a parser.inc file in that directory.
 *
 * @package Rewrite
 * @subpackage Classes
 * @author Douglas Cau <douglas@cau.se>
 * @version $Revision: 17580 $
 * @abstract
 */
class RewriteParser {

    /**
     * The id of this parser
     *
     * @var string parser id
     * @access private
     */
    var $_parserId;

    /**
     * The name of this URL generator class
     *
     * @var string URL generator class name
     * @access private
     */
    var $_urlGeneratorId;

    /**
     * The type of this parser.  Can be either 'preGallery' or 'inGallery'
     *
     * @var string URL generator class name
     * @access private
     */
    var $_type;

    /**
     * Saves the active rewrite rules.  This needs to be implemented by the specific plugin.  It
     * needs to save two rewrite params, activeRules and shortUrls.  activeRules is just a
     * serialized array of the given activeRules and shortUrls is returned by
     * RewriteHelper::parseActiveRules().  It returns REWRITE_STATUS_OK on success.
     *
     * @param array $activeRules (if null, or not set, it defaults to the current rules)
     * @param GalleryModule $upgradeModule (optional)
     * @return array GalleryStatus a status code
     *               int rewrite status code (REWRITE_STATUS_OK on success)
     *               array string module (on error)
     *                     int rule id (on error)
     */
    function saveActiveRules($activeRules=null, $upgradeModule=null) {
	return array(GalleryCoreApi::error(ERROR_UNIMPLEMENTED), null, null);
    }

    /**
     * Saves list of hosts Gallery allows as referrer and if Gallery should allow an empty referrer.
     * This needs to be implemented by the specific plugin.  It needs to save a serialized array of
     * the hosts and the value of allowEmptyReferer to the params accessList and allowEmptyReferer.
     *
     * @param array $accessList access list of referer hosts
     * @param boolean $allowEmptyReferer true if Gallery should allow empty referrer
     * @return array GalleryStatus a status code
     *               int rewrite status code (REWRITE_STATUS_OK on success)
     */
    function saveAccessList($accessList, $allowEmptyReferer) {
	return array(GalleryCoreApi::error(ERROR_UNIMPLEMENTED), null);
    }

    /**
     * By default there's nothing to configure, so we return success.
     *
     * @return array GalleryStatus a status code
     *               boolean true if this parser needs configuration
     */
    function needsConfiguration() {
	return array(null, false);
    }

    /**
     * This function is called when new rules are saved and by rewrite.AdminRewrite to know if this
     * rule should be displayed.  If the parser overrides this function it needs to call this (the
     * parent).  It also verifies that locked rules are saved with the original pattern.  We perform
     * a sanity check to minimize possible conflicts and bad regular expressions.
     *
     * @param array $rule rewrite rule
     * @param array $activeRule (optional) array ('pattern' => string pattern) set to the custom
     *        active rule when called from saveActiveRules
     * @return boolean true if the rule is valid
     */
    function isValidRule($rule, $activeRule=null) {
	if (isset($rule['parser']) && $rule['parser'] != $this->getParserType()) {
	    return false;
	}

	/* Only supported by preGallery parsers */
	if (isset($rule['conditions']) && $this->getParserType() != 'preGallery') {
	    return false;
	}

	/* Only supported by preGallery parsers */
	if (isset($rule['restrict']) && $this->getParserType() != 'preGallery') {
	    return false;
	}

	if (isset($activeRule) && (isset($activeRule['pattern']) != isset($rule['pattern']))) {
	    return false;
	}

	if (isset($activeRule['pattern']) && isset($rule['pattern']) && isset($rule['locked'])
		&& $activeRule['pattern'] != $rule['pattern']) {
	    return false;
	}

	if (isset($activeRule['pattern'])
		&& !preg_match('/^[a-zA-Z0-9\/\.\%\-]+$/', $activeRule['pattern'])) {
	    return false;
	}

	return true;
    }

    /**
     * Returns translated error message, called from AdminRewrite when an unsucsessful save has been
     * made.  A valid $code is anything that $this->saveActiveRules would return if an error occurs.
     *
     * @param int $code rewrite status code
     * @param RewriteModule $rewriteModule (optional)
     * @return array GalleryStatus a status code
     *               string translated error message
     */
    function getErrorMessage($code, $rewriteModule=null) {
	if (!isset($rewriteModule)) {
	    list ($ret, $rewriteModule) = GalleryCoreApi::loadPlugin('module', 'rewrite');
	    if ($ret) {
		return array($ret, null);
	    }
	}

	switch ($code) {
	case REWRITE_STATUS_BAD_KEYWORD:
	    return array(null,
		$rewriteModule->translate('Bad keyword.'));
	case REWRITE_STATUS_DUPE_SHORT_URL:
	    return array(null,
		$rewriteModule->translate('Duplicate short URL rule.'));
	case REWRITE_STATUS_INVALID_PATTERN:
	    return array(null,
		$rewriteModule->translate('Invalid pattern.'));
	case REWRITE_STATUS_EMPTY_VALUE:
	    return array(null,
		$rewriteModule->translate('Empty configuration value.'));
	}

	return array(null, null);
    }

    /**
     * Displays the test results if the template variable $TestResults.body is set.  It should be a
     * Gallery base dir relative path.
     *
     * @param GalleryTemplate $template
     * @param array $form the form values
     * @return GalleryStatus a status code
     */
    function loadTestResultsTemplate(&$template, &$form) {
	return null;
    }

    /**
     * Handles the submitted form and should save any settings (ie. forced tests).
     *
     * @param array $form the form values
     * @return array GalleryStatus a status code
     *               array error codes
     *               array status codes
     */
    function handleTestResultsRequest($form) {
	return array(null, array(), array());
    }

    /**
     * Displays the parser configuration if the template variable $AdminParser.body is set.  It
     * should be a Gallery base dir relative path.
     *
     * @param GalleryTemplate $template
     * @param array $form the form values
     * @return GalleryStatus a status code
     */
    function loadAdminParserTemplate(&$template, &$form) {
	return null;
    }

    /**
     * Handles the submitted form and should save the settings.
     *
     * @param array $form the form values
     * @return array GalleryStatus a status code
     *               array error codes
     *               array status codes
     */
    function handleAdminParserRequest($form) {
	return array(null, array(), array());
    }

    /**
     * @see RewriteApi::needsEmbedConfig
     */
    function needsEmbedConfig() {
	return array(null, false);
    }

    /**
     * @see RewriteApi::fetchEmbedConfig
     */
    function fetchEmbedConfig() {
	return array(null, array());
    }

    /**
     * @see RewriteApi::saveEmbedConfig
     */
    function saveEmbedConfig($params) {
	return array(null, REWRITE_STATUS_OK, null);
    }

    /* Getters and setters below */

    function _setParserId($parserId) {
	$this->_parserId = $parserId;
    }

    function getParserId() {
	return $this->_parserId;
    }

    function _setUrlGeneratorId($urlGenerator) {
	$this->_urlGeneratorId = $urlGenerator;
    }

    function getUrlGeneratorId() {
	return $this->_urlGeneratorId;
    }

    function _setParserType($parserType) {
	$this->_type = $parserType;
    }

    function getParserType() {
	return $this->_type;
    }
}
?>