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/>.

/**

 * Private imscp module utility functions

 *

 * @package mod_imscp

 * @copyright  2009 Petr Skoda  {@link http://skodak.org}

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

 */

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

require_once("$CFG->dirroot/mod/imscp/lib.php");

require_once("$CFG->libdir/filelib.php");

require_once("$CFG->libdir/resourcelib.php");

/**

 * Print IMSCP content to page.

 *

 * @param stdClass $imscp module instance.

 * @param stdClass $cm course module.

 * @param stdClass $course record.

 */

function imscp_print_content($imscp, $cm, $course) {

    global $PAGE, $CFG;

    $items = array_filter((array) unserialize_array($imscp->structure));

    echo '<div id="imscp_layout">';

    echo '<div id="imscp_toc">';

    echo '<div id="imscp_tree"><ul>';

    foreach ($items as $item) {

        echo imscp_htmllize_item($item, $imscp, $cm);

    }

    echo '</ul></div>';

    echo '<div id="imscp_nav" style="display:none">';

    echo '<button id="nav_skipprev">&lt;&lt;</button><button id="nav_prev">&lt;</button><button id="nav_up">^</button>';

    echo '<button id="nav_next">&gt;</button><button id="nav_skipnext">&gt;&gt;</button>';

    echo '</div>';

    echo '</div>';

    echo '</div>';

    $PAGE->requires->js_init_call('M.mod_imscp.init');

}

/**

 * Internal function - creates htmls structure suitable for YUI tree.

 */

function imscp_htmllize_item($item, $imscp, $cm) {

    global $CFG;

    if ($item['href']) {

        if (preg_match('|^https?://|', $item['href'])) {

            $url = $item['href'];

        } else {

            $context = context_module::instance($cm->id);

            $urlbase = "$CFG->wwwroot/pluginfile.php";

            $path = '/'.$context->id.'/mod_imscp/content/'.$imscp->revision.'/'.$item['href'];

            $url = file_encode_url($urlbase, $path, false);

        }

        $result = "<li><a href=\"$url\">".$item['title'].'</a>';

    } else {

        $result = '<li>'.$item['title'];

    }

    if ($item['subitems']) {

        $result .= '<ul>';

        foreach ($item['subitems'] as $subitem) {

            $result .= imscp_htmllize_item($subitem, $imscp, $cm);

        }

        $result .= '</ul>';

    }

    $result .= '</li>';

    return $result;

}

/**

 * Parse an IMS content package's manifest file to determine its structure

 * @param object $imscp

 * @param object $context

 * @return array

 */

function imscp_parse_structure($imscp, $context) {

    $fs = get_file_storage();

    if (!$manifestfile = $fs->get_file($context->id, 'mod_imscp', 'content', $imscp->revision, '/', 'imsmanifest.xml')) {

        return null;

    }

    return imscp_parse_manifestfile($manifestfile->get_content(), $imscp, $context);

}

/**

 * Parse the contents of a IMS package's manifest file.

 * @param string $manifestfilecontents the contents of the manifest file

 * @return array

 */

function imscp_parse_manifestfile($manifestfilecontents, $imscp, $context) {

    $doc = new DOMDocument();

    if (!$doc->loadXML($manifestfilecontents, LIBXML_NONET)) {

        return null;

    }

    // We put this fake URL as base in order to detect path changes caused by xml:base attributes.

    $doc->documentURI = 'http://grrr/';

    $xmlorganizations = $doc->getElementsByTagName('organizations');

    if (empty($xmlorganizations->length)) {

        return null;

    }

    $default = null;

    if ($xmlorganizations->item(0)->attributes->getNamedItem('default')) {

        $default = $xmlorganizations->item(0)->attributes->getNamedItem('default')->nodeValue;

    }

    $xmlorganization = $doc->getElementsByTagName('organization');

    if (empty($xmlorganization->length)) {

        return null;

    }

    $organization = null;

    foreach ($xmlorganization as $org) {

        if (is_null($organization)) {

            // Use first if default nor found.

            $organization = $org;

        }

        if (!$org->attributes->getNamedItem('identifier')) {

            continue;

        }

        if ($default === $org->attributes->getNamedItem('identifier')->nodeValue) {

            // Found default - use it.

            $organization = $org;

            break;

        }

    }

    // Load all resources.

    $resources = array();

    $xmlresources = $doc->getElementsByTagName('resource');

    foreach ($xmlresources as $res) {

        if (!$identifier = $res->attributes->getNamedItem('identifier')) {

            continue;

        }

        $identifier = $identifier->nodeValue;

        if ($xmlbase = $res->baseURI) {

            // Undo the fake URL, we are interested in relative links only.

            $xmlbase = str_replace('http://grrr/', '/', $xmlbase);

            $xmlbase = rtrim($xmlbase, '/').'/';

        } else {

            $xmlbase = '';

        }

        if (!$href = $res->attributes->getNamedItem('href')) {

            // If href not found look for <file href="help.htm"/>.

            $fileresources = $res->getElementsByTagName('file');

            foreach ($fileresources as $file) {

                $href = $file->getAttribute('href');

            }

            if (pathinfo($href, PATHINFO_EXTENSION) == 'xml') {

                $href = imscp_recursive_href($href, $imscp, $context);

            }

            if (empty($href)) {

                continue;

            }

        } else {

            $href = $href->nodeValue;

        }

        if (strpos($href, 'http://') !== 0) {

            $href = $xmlbase.$href;

        }

        // Item href cleanup - Some packages are poorly done and use \ in urls.

        $href = ltrim(strtr($href, "\\", '/'), '/');

        $resources[$identifier] = $href;

    }

    $items = array();

    foreach ($organization->childNodes as $child) {

        if ($child->nodeName === 'item') {

            if (!$item = imscp_recursive_item($child, 0, $resources)) {

                continue;

            }

            $items[] = $item;

        }

    }

    return $items;

}

function imscp_recursive_href($manifestfilename, $imscp, $context) {

    $fs = get_file_storage();

    $dirname = dirname($manifestfilename);

    $filename = basename($manifestfilename);

    if ($dirname !== '/') {

        $dirname = "/$dirname/";

    }

    if (!$manifestfile = $fs->get_file($context->id, 'mod_imscp', 'content', $imscp->revision, $dirname, $filename)) {

        return null;

    }

    $doc = new DOMDocument();

    if (!$doc->loadXML($manifestfile->get_content(), LIBXML_NONET)) {

        return null;

    }

    $xmlresources = $doc->getElementsByTagName('resource');

    foreach ($xmlresources as $res) {

        if (!$href = $res->attributes->getNamedItem('href')) {

            $fileresources = $res->getElementsByTagName('file');

            foreach ($fileresources as $file) {

                $href = $file->getAttribute('href');

                if (pathinfo($href, PATHINFO_EXTENSION) == 'xml') {

                    $href = imscp_recursive_href($href, $imscp, $context);

                }

                if (pathinfo($href, PATHINFO_EXTENSION) == 'htm' || pathinfo($href, PATHINFO_EXTENSION) == 'html') {

                    return $href;

                }

            }

        }

    }

    return $manifestfilename;

}

function imscp_recursive_item($xmlitem, $level, $resources) {

    $identifierref = '';

    if ($identifierref = $xmlitem->attributes->getNamedItem('identifierref')) {

        $identifierref = $identifierref->nodeValue;

    }

    $title = '?';

    $subitems = array();

    foreach ($xmlitem->childNodes as $child) {

        if ($child->nodeName === 'title') {

            $title = $child->textContent;

        } else if ($child->nodeName === 'item') {

            if ($subitem = imscp_recursive_item($child, $level + 1, $resources)) {

                $subitems[] = $subitem;

            }

        }

    }

    return array('href'     => isset($resources[$identifierref]) ? $resources[$identifierref] : '',

                 'title'    => $title,

                 'level'    => $level,

                 'subitems' => $subitems,

                );

}

/**

 * Wrapper for function libxml_disable_entity_loader() deprecated in PHP 8

 *

 * Method was deprecated in PHP 8 and it shows deprecation message. However it is still

 * required in the previous versions on PHP. While Moodle supports both PHP 7 and 8 we need to keep it.

 * @see https://php.watch/versions/8.0/libxml_disable_entity_loader-deprecation

 *

 * @param bool $value

 * @return bool

 *

 * @deprecated since Moodle 4.3

 */

function imscp_libxml_disable_entity_loader(bool $value): bool {

    debugging(__FUNCTION__ . '() is deprecated, please do not use it any more', DEBUG_DEVELOPER);

    return true;

}

/**

 * File browsing support class

 *

 * @copyright  2009 Petr Skoda  {@link http://skodak.org}

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

 */

class imscp_file_info extends file_info {

    protected $course;

    protected $cm;

    protected $areas;

    protected $filearea;

    public function __construct($browser, $course, $cm, $context, $areas, $filearea) {

        parent::__construct($browser, $context);

        $this->course   = $course;

        $this->cm       = $cm;

        $this->areas    = $areas;

        $this->filearea = $filearea;

    }

    /**

     * Returns list of standard virtual file/directory identification.

     * The difference from stored_file parameters is that null values

     * are allowed in all fields

     * @return array with keys contextid, filearea, itemid, filepath and filename

     */

    public function get_params() {

        return array('contextid' => $this->context->id,

                     'component' => 'mod_imscp',

                     'filearea'  => $this->filearea,

                     'itemid'    => null,

                     'filepath'  => null,

                     'filename'  => null);

    }

    /**

     * Returns localised visible name.

     * @return string

     */

    public function get_visible_name() {

        return $this->areas[$this->filearea];

    }

    /**

     * Can I add new files or directories?

     * @return bool

     */

    public function is_writable() {

        return false;

    }

    /**

     * Is directory?

     * @return bool

     */

    public function is_directory() {

        return true;

    }

    /**

     * Returns list of children.

     * @return array of file_info instances

     */

    public function get_children() {

        return $this->get_filtered_children('*', false, true);

    }

    /**

     * Help function to return files matching extensions or their count

     *

     * @param string|array $extensions, either '*' or array of lowercase extensions, i.e. array('.gif','.jpg')

     * @param bool|int $countonly if false returns the children, if an int returns just the

     *    count of children but stops counting when $countonly number of children is reached

     * @param bool $returnemptyfolders if true returns items that don't have matching files inside

     * @return array|int array of file_info instances or the count

     */

    private function get_filtered_children($extensions = '*', $countonly = false, $returnemptyfolders = false) {

        global $DB;

        $params = array('contextid' => $this->context->id,

            'component' => 'mod_imscp',

            'filearea' => $this->filearea);

        $sql = 'SELECT DISTINCT itemid

                    FROM {files}

                    WHERE contextid = :contextid

                    AND component = :component

                    AND filearea = :filearea';

        if (!$returnemptyfolders) {

            $sql .= ' AND filename <> :emptyfilename';

            $params['emptyfilename'] = '.';

        }

        list($sql2, $params2) = $this->build_search_files_sql($extensions);

        $sql .= ' '.$sql2;

        $params = array_merge($params, $params2);

        if ($countonly !== false) {

            $sql .= ' ORDER BY itemid';

        }

        $rs = $DB->get_recordset_sql($sql, $params);

        $children = array();

        foreach ($rs as $record) {

            if ($child = $this->browser->get_file_info($this->context, 'mod_imscp', $this->filearea, $record->itemid)) {

                $children[] = $child;

                if ($countonly !== false && count($children) >= $countonly) {

                    break;

                }

            }

        }

        $rs->close();

        if ($countonly !== false) {

            return count($children);

        }

        return $children;

    }

    /**

     * Returns list of children which are either files matching the specified extensions

     * or folders that contain at least one such file.

     *

     * @param string|array $extensions, either '*' or array of lowercase extensions, i.e. array('.gif','.jpg')

     * @return array of file_info instances

     */

    public function get_non_empty_children($extensions = '*') {

        return $this->get_filtered_children($extensions, false);

    }

    /**

     * Returns the number of children which are either files matching the specified extensions

     * or folders containing at least one such file.

     *

     * @param string|array $extensions, for example '*' or array('.gif','.jpg')

     * @param int $limit stop counting after at least $limit non-empty children are found

     * @return int

     */

    public function count_non_empty_children($extensions = '*', $limit = 1) {

        return $this->get_filtered_children($extensions, $limit);

    }

    /**

     * Returns parent file_info instance

     * @return file_info or null for root

     */

    public function get_parent() {

        return $this->browser->get_file_info($this->context);

    }

}