Proyectos de Subversion Moodle

<?php

// This file is part of Moodle - http://moodle.org/

//

// Moodle 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 3 of the License, or

// (at your option) any later version.

//

// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**

 * Filter converting emoticon texts into images

 *

 * This filter uses the emoticon settings in Site admin > Appearance > HTML settings

 * and replaces emoticon texts with images.

 *

 * @package    filter

 * @subpackage emoticon

 * @see        emoticon_manager

 * @copyright  2010 David Mudrak <david@moodle.com>

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

defined('MOODLE_INTERNAL') || die();

class filter_emoticon extends moodle_text_filter {

    /**

     * Internal cache used for replacing. Multidimensional array;

     * - dimension 1: language,

     * - dimension 2: theme.

     * @var array

     */

    protected static $emoticontexts = array();

    /**

     * Internal cache used for replacing. Multidimensional array;

     * - dimension 1: language,

     * - dimension 2: theme.

     * @var array

     */

    protected static $emoticonimgs = array();

    /**

     * Apply the filter to the text

     *

     * @see filter_manager::apply_filter_chain()

     * @param string $text to be processed by the text

     * @param array $options filter options

     * @return string text after processing

     */

    public function filter($text, array $options = array()) {

        if (!isset($options['originalformat'])) {

            // if the format is not specified, we are probably called by {@see format_string()}

            // in that case, it would be dangerous to replace text with the image because it could

            // be stripped. therefore, we do nothing

            return $text;

        }

        if (in_array($options['originalformat'], explode(',', get_config('filter_emoticon', 'formats')))) {

            return $this->replace_emoticons($text);

        }

        return $text;

    }

    ////////////////////////////////////////////////////////////////////////////

    // internal implementation starts here

    ////////////////////////////////////////////////////////////////////////////

    /**

     * Replace emoticons found in the text with their images

     *

     * @param string $text to modify

     * @return string the modified result

     */

    protected function replace_emoticons($text) {

        global $CFG, $OUTPUT, $PAGE;

        $lang = current_language();

        $theme = $PAGE->theme->name;

        if (!isset(self::$emoticontexts[$lang][$theme]) or !isset(self::$emoticonimgs[$lang][$theme])) {

            // prepare internal caches

            $manager = get_emoticon_manager();

            $emoticons = $manager->get_emoticons();

            self::$emoticontexts[$lang][$theme] = array();

            self::$emoticonimgs[$lang][$theme] = array();

            foreach ($emoticons as $emoticon) {

                self::$emoticontexts[$lang][$theme][] = $emoticon->text;

                self::$emoticonimgs[$lang][$theme][] = $OUTPUT->render($manager->prepare_renderable_emoticon($emoticon));

            }

            unset($emoticons);

        }

        if (empty(self::$emoticontexts[$lang][$theme])) { // No emoticons defined, nothing to process here.

            return $text;

        }

        // Detect all zones that we should not handle (including the nested tags).

        $processing = preg_split('/(<\/?(?:span|script|pre)[^>]*>)/is', $text, 0, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY);

        // Initialize the results.

        $resulthtml = "";

        $exclude = 0;

        // Define the patterns that mark the start of the forbidden zones.

        $excludepattern = array('/^<script/is', '/^<span[^>]+class="nolink[^"]*"/is', '/^<pre/is');

        // Loop through the fragments.

        foreach ($processing as $fragment) {

            // If we are not ignoring, we MUST test if we should.

            if ($exclude == 0) {

                foreach ($excludepattern as $exp) {

                    if (preg_match($exp, $fragment)) {

                        $exclude = $exclude + 1;

                        break;

                    }

                }

            }

            if ($exclude > 0) {

                // If we are ignoring the fragment, then we must check if we may have reached the end of the zone.

                if (strpos($fragment, '</span') !== false || strpos($fragment, '</script') !== false

                    || strpos($fragment, '</pre') !== false) {

                    $exclude -= 1;

                    // This is needed because of a double increment at the first element.

                    if ($exclude == 1) {

                        $exclude -= 1;

                    }

                } else if (strpos($fragment, '<span') !== false || strpos($fragment, '<script') !== false

                    || strpos($fragment, '<pre') !== false) {

                    // If we find a nested tag we increase the exclusion level.

                    $exclude = $exclude + 1;

                }

            } else if (strpos($fragment, '<span') === false ||

                       strpos($fragment, '</span') === false) {

                // This is the meat of the code - this is run every time.

                // This code only runs for fragments that are not ignored (including the tags themselves).

                $fragment = str_replace(self::$emoticontexts[$lang][$theme], self::$emoticonimgs[$lang][$theme], $fragment);

            }

            $resulthtml .= $fragment;

        }

        return $resulthtml;

    }

}