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Differences Between: [Versions 310 and 401] [Versions 39 and 401] [Versions 401 and 403]

   1  <?php
   2  // This file is part of Moodle - http://moodle.org/
   3  //
   4  // Moodle is free software: you can redistribute it and/or modify
   5  // it under the terms of the GNU General Public License as published by
   6  // the Free Software Foundation, either version 3 of the License, or
   7  // (at your option) any later version.
   8  //
   9  // Moodle is distributed in the hope that it will be useful,
  10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  // GNU General Public License for more details.
  13  //
  14  // You should have received a copy of the GNU General Public License
  15  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16  
  17  /**
  18   * Private imscp module utility functions
  19   *
  20   * @package mod_imscp
  21   * @copyright  2009 Petr Skoda  {@link http://skodak.org}
  22   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23   */
  24  
  25  defined('MOODLE_INTERNAL') || die();
  26  
  27  require_once("$CFG->dirroot/mod/imscp/lib.php");
  28  require_once("$CFG->libdir/filelib.php");
  29  require_once("$CFG->libdir/resourcelib.php");
  30  
  31  /**
  32   * Print IMSCP content to page.
  33   *
  34   * @param stdClass $imscp module instance.
  35   * @param stdClass $cm course module.
  36   * @param stdClass $course record.
  37   */
  38  function imscp_print_content($imscp, $cm, $course) {
  39      global $PAGE, $CFG;
  40  
  41      $items = array_filter((array) unserialize_array($imscp->structure));
  42  
  43      echo '<div id="imscp_layout">';
  44      echo '<div id="imscp_toc">';
  45      echo '<div id="imscp_tree"><ul>';
  46      foreach ($items as $item) {
  47          echo imscp_htmllize_item($item, $imscp, $cm);
  48      }
  49      echo '</ul></div>';
  50      echo '<div id="imscp_nav" style="display:none">';
  51      echo '<button id="nav_skipprev">&lt;&lt;</button><button id="nav_prev">&lt;</button><button id="nav_up">^</button>';
  52      echo '<button id="nav_next">&gt;</button><button id="nav_skipnext">&gt;&gt;</button>';
  53      echo '</div>';
  54      echo '</div>';
  55      echo '</div>';
  56  
  57      $PAGE->requires->js_init_call('M.mod_imscp.init');
  58  }
  59  
  60  /**
  61   * Internal function - creates htmls structure suitable for YUI tree.
  62   */
  63  function imscp_htmllize_item($item, $imscp, $cm) {
  64      global $CFG;
  65  
  66      if ($item['href']) {
  67          if (preg_match('|^https?://|', $item['href'])) {
  68              $url = $item['href'];
  69          } else {
  70              $context = context_module::instance($cm->id);
  71              $urlbase = "$CFG->wwwroot/pluginfile.php";
  72              $path = '/'.$context->id.'/mod_imscp/content/'.$imscp->revision.'/'.$item['href'];
  73              $url = file_encode_url($urlbase, $path, false);
  74          }
  75          $result = "<li><a href=\"$url\">".$item['title'].'</a>';
  76      } else {
  77          $result = '<li>'.$item['title'];
  78      }
  79      if ($item['subitems']) {
  80          $result .= '<ul>';
  81          foreach ($item['subitems'] as $subitem) {
  82              $result .= imscp_htmllize_item($subitem, $imscp, $cm);
  83          }
  84          $result .= '</ul>';
  85      }
  86      $result .= '</li>';
  87  
  88      return $result;
  89  }
  90  
  91  /**
  92   * Parse an IMS content package's manifest file to determine its structure
  93   * @param object $imscp
  94   * @param object $context
  95   * @return array
  96   */
  97  function imscp_parse_structure($imscp, $context) {
  98      $fs = get_file_storage();
  99  
 100      if (!$manifestfile = $fs->get_file($context->id, 'mod_imscp', 'content', $imscp->revision, '/', 'imsmanifest.xml')) {
 101          return null;
 102      }
 103  
 104      return imscp_parse_manifestfile($manifestfile->get_content(), $imscp, $context);
 105  }
 106  
 107  /**
 108   * Parse the contents of a IMS package's manifest file.
 109   * @param string $manifestfilecontents the contents of the manifest file
 110   * @return array
 111   */
 112  function imscp_parse_manifestfile($manifestfilecontents, $imscp, $context) {
 113      $doc = new DOMDocument();
 114      $oldentities = imscp_libxml_disable_entity_loader(true);
 115      if (!$doc->loadXML($manifestfilecontents, LIBXML_NONET)) {
 116          return null;
 117      }
 118      imscp_libxml_disable_entity_loader($oldentities);
 119  
 120      // We put this fake URL as base in order to detect path changes caused by xml:base attributes.
 121      $doc->documentURI = 'http://grrr/';
 122  
 123      $xmlorganizations = $doc->getElementsByTagName('organizations');
 124      if (empty($xmlorganizations->length)) {
 125          return null;
 126      }
 127      $default = null;
 128      if ($xmlorganizations->item(0)->attributes->getNamedItem('default')) {
 129          $default = $xmlorganizations->item(0)->attributes->getNamedItem('default')->nodeValue;
 130      }
 131      $xmlorganization = $doc->getElementsByTagName('organization');
 132      if (empty($xmlorganization->length)) {
 133          return null;
 134      }
 135      $organization = null;
 136      foreach ($xmlorganization as $org) {
 137          if (is_null($organization)) {
 138              // Use first if default nor found.
 139              $organization = $org;
 140          }
 141          if (!$org->attributes->getNamedItem('identifier')) {
 142              continue;
 143          }
 144          if ($default === $org->attributes->getNamedItem('identifier')->nodeValue) {
 145              // Found default - use it.
 146              $organization = $org;
 147              break;
 148          }
 149      }
 150  
 151      // Load all resources.
 152      $resources = array();
 153  
 154      $xmlresources = $doc->getElementsByTagName('resource');
 155      foreach ($xmlresources as $res) {
 156          if (!$identifier = $res->attributes->getNamedItem('identifier')) {
 157              continue;
 158          }
 159          $identifier = $identifier->nodeValue;
 160          if ($xmlbase = $res->baseURI) {
 161              // Undo the fake URL, we are interested in relative links only.
 162              $xmlbase = str_replace('http://grrr/', '/', $xmlbase);
 163              $xmlbase = rtrim($xmlbase, '/').'/';
 164          } else {
 165              $xmlbase = '';
 166          }
 167          if (!$href = $res->attributes->getNamedItem('href')) {
 168              // If href not found look for <file href="help.htm"/>.
 169              $fileresources = $res->getElementsByTagName('file');
 170              foreach ($fileresources as $file) {
 171                  $href = $file->getAttribute('href');
 172              }
 173              if (pathinfo($href, PATHINFO_EXTENSION) == 'xml') {
 174                  $href = imscp_recursive_href($href, $imscp, $context);
 175              }
 176              if (empty($href)) {
 177                  continue;
 178              }
 179          } else {
 180              $href = $href->nodeValue;
 181          }
 182          if (strpos($href, 'http://') !== 0) {
 183              $href = $xmlbase.$href;
 184          }
 185          // Item href cleanup - Some packages are poorly done and use \ in urls.
 186          $href = ltrim(strtr($href, "\\", '/'), '/');
 187          $resources[$identifier] = $href;
 188      }
 189  
 190      $items = array();
 191      foreach ($organization->childNodes as $child) {
 192          if ($child->nodeName === 'item') {
 193              if (!$item = imscp_recursive_item($child, 0, $resources)) {
 194                  continue;
 195              }
 196              $items[] = $item;
 197          }
 198      }
 199  
 200      return $items;
 201  }
 202  
 203  function imscp_recursive_href($manifestfilename, $imscp, $context) {
 204      $fs = get_file_storage();
 205  
 206      $dirname = dirname($manifestfilename);
 207      $filename = basename($manifestfilename);
 208  
 209      if ($dirname !== '/') {
 210          $dirname = "/$dirname/";
 211      }
 212  
 213      if (!$manifestfile = $fs->get_file($context->id, 'mod_imscp', 'content', $imscp->revision, $dirname, $filename)) {
 214          return null;
 215      }
 216  
 217      $doc = new DOMDocument();
 218      $oldentities = imscp_libxml_disable_entity_loader(true);
 219      if (!$doc->loadXML($manifestfile->get_content(), LIBXML_NONET)) {
 220          return null;
 221      }
 222      imscp_libxml_disable_entity_loader($oldentities);
 223  
 224      $xmlresources = $doc->getElementsByTagName('resource');
 225      foreach ($xmlresources as $res) {
 226          if (!$href = $res->attributes->getNamedItem('href')) {
 227              $fileresources = $res->getElementsByTagName('file');
 228              foreach ($fileresources as $file) {
 229                  $href = $file->getAttribute('href');
 230                  if (pathinfo($href, PATHINFO_EXTENSION) == 'xml') {
 231                      $href = imscp_recursive_href($href, $imscp, $context);
 232                  }
 233  
 234                  if (pathinfo($href, PATHINFO_EXTENSION) == 'htm' || pathinfo($href, PATHINFO_EXTENSION) == 'html') {
 235                      return $href;
 236                  }
 237              }
 238          }
 239      }
 240  
 241      return $manifestfilename;
 242  }
 243  
 244  function imscp_recursive_item($xmlitem, $level, $resources) {
 245      $identifierref = '';
 246      if ($identifierref = $xmlitem->attributes->getNamedItem('identifierref')) {
 247          $identifierref = $identifierref->nodeValue;
 248      }
 249  
 250      $title = '?';
 251      $subitems = array();
 252  
 253      foreach ($xmlitem->childNodes as $child) {
 254          if ($child->nodeName === 'title') {
 255              $title = $child->textContent;
 256  
 257          } else if ($child->nodeName === 'item') {
 258              if ($subitem = imscp_recursive_item($child, $level + 1, $resources)) {
 259                  $subitems[] = $subitem;
 260              }
 261          }
 262      }
 263  
 264      return array('href'     => isset($resources[$identifierref]) ? $resources[$identifierref] : '',
 265                   'title'    => $title,
 266                   'level'    => $level,
 267                   'subitems' => $subitems,
 268                  );
 269  }
 270  
 271  /**
 272   * Wrapper for function libxml_disable_entity_loader() deprecated in PHP 8
 273   *
 274   * Method was deprecated in PHP 8 and it shows deprecation message. However it is still
 275   * required in the previous versions on PHP. While Moodle supports both PHP 7 and 8 we need to keep it.
 276   * @see https://php.watch/versions/8.0/libxml_disable_entity_loader-deprecation
 277   *
 278   * @param bool $value
 279   * @return bool
 280   */
 281  function imscp_libxml_disable_entity_loader(bool $value): bool {
 282      if (PHP_VERSION_ID < 80000) {
 283          return (bool)libxml_disable_entity_loader($value);
 284      }
 285      return true;
 286  }
 287  
 288  /**
 289   * File browsing support class
 290   *
 291   * @copyright  2009 Petr Skoda  {@link http://skodak.org}
 292   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 293   */
 294  class imscp_file_info extends file_info {
 295      protected $course;
 296      protected $cm;
 297      protected $areas;
 298      protected $filearea;
 299  
 300      public function __construct($browser, $course, $cm, $context, $areas, $filearea) {
 301          parent::__construct($browser, $context);
 302          $this->course   = $course;
 303          $this->cm       = $cm;
 304          $this->areas    = $areas;
 305          $this->filearea = $filearea;
 306      }
 307  
 308      /**
 309       * Returns list of standard virtual file/directory identification.
 310       * The difference from stored_file parameters is that null values
 311       * are allowed in all fields
 312       * @return array with keys contextid, filearea, itemid, filepath and filename
 313       */
 314      public function get_params() {
 315          return array('contextid' => $this->context->id,
 316                       'component' => 'mod_imscp',
 317                       'filearea'  => $this->filearea,
 318                       'itemid'    => null,
 319                       'filepath'  => null,
 320                       'filename'  => null);
 321      }
 322  
 323      /**
 324       * Returns localised visible name.
 325       * @return string
 326       */
 327      public function get_visible_name() {
 328          return $this->areas[$this->filearea];
 329      }
 330  
 331      /**
 332       * Can I add new files or directories?
 333       * @return bool
 334       */
 335      public function is_writable() {
 336          return false;
 337      }
 338  
 339      /**
 340       * Is directory?
 341       * @return bool
 342       */
 343      public function is_directory() {
 344          return true;
 345      }
 346  
 347      /**
 348       * Returns list of children.
 349       * @return array of file_info instances
 350       */
 351      public function get_children() {
 352          return $this->get_filtered_children('*', false, true);
 353      }
 354  
 355      /**
 356       * Help function to return files matching extensions or their count
 357       *
 358       * @param string|array $extensions, either '*' or array of lowercase extensions, i.e. array('.gif','.jpg')
 359       * @param bool|int $countonly if false returns the children, if an int returns just the
 360       *    count of children but stops counting when $countonly number of children is reached
 361       * @param bool $returnemptyfolders if true returns items that don't have matching files inside
 362       * @return array|int array of file_info instances or the count
 363       */
 364      private function get_filtered_children($extensions = '*', $countonly = false, $returnemptyfolders = false) {
 365          global $DB;
 366          $params = array('contextid' => $this->context->id,
 367              'component' => 'mod_imscp',
 368              'filearea' => $this->filearea);
 369          $sql = 'SELECT DISTINCT itemid
 370                      FROM {files}
 371                      WHERE contextid = :contextid
 372                      AND component = :component
 373                      AND filearea = :filearea';
 374          if (!$returnemptyfolders) {
 375              $sql .= ' AND filename <> :emptyfilename';
 376              $params['emptyfilename'] = '.';
 377          }
 378          list($sql2, $params2) = $this->build_search_files_sql($extensions);
 379          $sql .= ' '.$sql2;
 380          $params = array_merge($params, $params2);
 381          if ($countonly !== false) {
 382              $sql .= ' ORDER BY itemid';
 383          }
 384  
 385          $rs = $DB->get_recordset_sql($sql, $params);
 386          $children = array();
 387          foreach ($rs as $record) {
 388              if ($child = $this->browser->get_file_info($this->context, 'mod_imscp', $this->filearea, $record->itemid)) {
 389                  $children[] = $child;
 390                  if ($countonly !== false && count($children) >= $countonly) {
 391                      break;
 392                  }
 393              }
 394          }
 395          $rs->close();
 396          if ($countonly !== false) {
 397              return count($children);
 398          }
 399          return $children;
 400      }
 401  
 402      /**
 403       * Returns list of children which are either files matching the specified extensions
 404       * or folders that contain at least one such file.
 405       *
 406       * @param string|array $extensions, either '*' or array of lowercase extensions, i.e. array('.gif','.jpg')
 407       * @return array of file_info instances
 408       */
 409      public function get_non_empty_children($extensions = '*') {
 410          return $this->get_filtered_children($extensions, false);
 411      }
 412  
 413      /**
 414       * Returns the number of children which are either files matching the specified extensions
 415       * or folders containing at least one such file.
 416       *
 417       * @param string|array $extensions, for example '*' or array('.gif','.jpg')
 418       * @param int $limit stop counting after at least $limit non-empty children are found
 419       * @return int
 420       */
 421      public function count_non_empty_children($extensions = '*', $limit = 1) {
 422          return $this->get_filtered_children($extensions, $limit);
 423      }
 424  
 425      /**
 426       * Returns parent file_info instance
 427       * @return file_info or null for root
 428       */
 429      public function get_parent() {
 430          return $this->browser->get_file_info($this->context);
 431      }
 432  }