[Summary view]

   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  /**
  19   * Utility class for browsing of module files.
  20   *
  21   * @package    core_files
  22   * @copyright  2008 Petr Skoda (http://skodak.org)
  23   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  24   */
  25  
  26  defined('MOODLE_INTERNAL') || die();
  27  
  28  /**
  29   * Represents a module context in the tree navigated by {@link file_browser}.
  30   *
  31   * @package    core_files
  32   * @copyright  2008 Petr Skoda (http://skodak.org)
  33   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  34   */
  35  class file_info_context_module extends file_info {
  36      /** @var stdClass Course object */
  37      protected $course;
  38      /** @var cm_info Course module object */
  39      protected $cm;
  40      /** @var string Module name */
  41      protected $modname;
  42      /** @var array Available file areas */
  43      protected $areas;
  44      /** @var array caches the result of last call to get_non_empty_children() */
  45      protected $nonemptychildren;
  46  
  47      /**
  48       * Constructor
  49       *
  50       * @param file_browser $browser file browser instance
  51       * @param stdClass $context context object
  52       * @param stdClass $course course object
  53       * @param stdClass $cm course module object
  54       * @param string $modname module name
  55       */
  56      public function __construct($browser, $context, $course, $cm, $modname) {
  57          global $CFG;
  58  
  59          parent::__construct($browser, $context);
  60          $this->course  = $course;
  61          $this->cm      = cm_info::create($cm);
  62          $this->modname = $this->cm->modname;
  63          $this->nonemptychildren = null;
  64  
  65          if ($functionname = component_callback_exists('mod_'.$modname, 'get_file_areas')) {
  66              $cm = $this->cm->get_course_module_record();
  67              $this->areas = $functionname($course, $cm, $context);
  68          } else {
  69              $this->areas = array();
  70          }
  71  
  72          unset($this->areas['intro']); // hardcoded, ignore attempts to override it
  73      }
  74  
  75      /**
  76       * Return information about this specific context level
  77       *
  78       * @param string $component component
  79       * @param string $filearea file area
  80       * @param int $itemid item ID
  81       * @param string $filepath file path
  82       * @param string $filename file name
  83       * @return file_info|null
  84       */
  85      public function get_file_info($component, $filearea, $itemid, $filepath, $filename) {
  86          // try to emulate require_login() tests here
  87          if (!isloggedin()) {
  88              return null;
  89          }
  90  
  91          $coursecontext = $this->context->get_course_context(true);
  92          if (!$this->course->visible and !has_capability('moodle/course:viewhiddencourses', $coursecontext)) {
  93              return null;
  94          }
  95  
  96          if (!is_viewing($this->context) and !$this->browser->is_enrolled($this->course->id)) {
  97              // no peaking here if not enrolled or inspector
  98              return null;
  99          }
 100  
 101          if (!$this->cm->uservisible) {
 102              // activity hidden sorry
 103              return null;
 104          }
 105  
 106          if (empty($component)) {
 107              return $this;
 108          }
 109  
 110          if ($component == 'mod_'.$this->modname and $filearea === 'intro') {
 111              return $this->get_area_intro($itemid, $filepath, $filename);
 112          } else if ($component == 'backup' and $filearea === 'activity') {
 113              return $this->get_area_backup($itemid, $filepath, $filename);
 114          }
 115  
 116          if ($functionname = component_callback_exists('mod_'.$this->modname, 'get_file_info')) {
 117              $cm = $this->cm->get_course_module_record();
 118              return $functionname($this->browser, $this->areas, $this->course, $cm,
 119                  $this->context, $filearea, $itemid, $filepath, $filename);
 120          }
 121  
 122          return null;
 123      }
 124  
 125      /**
 126       * Get a file from module intro area
 127       *
 128       * @param int $itemid item ID
 129       * @param string $filepath file path
 130       * @param string $filename file name
 131       * @return file_info|null
 132       */
 133      protected function get_area_intro($itemid, $filepath, $filename) {
 134          global $CFG;
 135  
 136          if (!plugin_supports('mod', $this->modname, FEATURE_MOD_INTRO, true) or !has_capability('moodle/course:managefiles', $this->context)) {
 137              return null;
 138          }
 139  
 140          $fs = get_file_storage();
 141  
 142          $filepath = is_null($filepath) ? '/' : $filepath;
 143          $filename = is_null($filename) ? '.' : $filename;
 144          if (!$storedfile = $fs->get_file($this->context->id, 'mod_'.$this->modname, 'intro', 0, $filepath, $filename)) {
 145              if ($filepath === '/' and $filename === '.') {
 146                  $storedfile = new virtual_root_file($this->context->id, 'mod_'.$this->modname, 'intro', 0);
 147              } else {
 148                  // not found
 149                  return null;
 150              }
 151          }
 152  
 153          $urlbase = $CFG->wwwroot.'/pluginfile.php';
 154          return new file_info_stored($this->browser, $this->context, $storedfile, $urlbase, get_string('moduleintro'), false, true, true, false);
 155      }
 156  
 157      /**
 158       * Get a file from module backup area
 159       *
 160       * @param int $itemid item ID
 161       * @param string $filepath file path
 162       * @param string $filename file name
 163       * @return file_info|null
 164       */
 165      protected function get_area_backup($itemid, $filepath, $filename) {
 166          global $CFG;
 167  
 168          if (!has_capability('moodle/backup:backupactivity', $this->context)) {
 169              return null;
 170          }
 171  
 172          $fs = get_file_storage();
 173  
 174          $filepath = is_null($filepath) ? '/' : $filepath;
 175          $filename = is_null($filename) ? '.' : $filename;
 176          if (!$storedfile = $fs->get_file($this->context->id, 'backup', 'activity', 0, $filepath, $filename)) {
 177              if ($filepath === '/' and $filename === '.') {
 178                  $storedfile = new virtual_root_file($this->context->id, 'backup', 'activity', 0);
 179              } else {
 180                  // not found
 181                  return null;
 182              }
 183          }
 184  
 185          $downloadable = has_capability('moodle/backup:downloadfile', $this->context);
 186          $uploadable   = has_capability('moodle/restore:uploadfile', $this->context);
 187  
 188          $urlbase = $CFG->wwwroot.'/pluginfile.php';
 189          return new file_info_stored($this->browser, $this->context, $storedfile, $urlbase, get_string('activitybackup', 'repository'), false, $downloadable, $uploadable, false);
 190      }
 191  
 192      /**
 193       * Returns localised visible name.
 194       *
 195       * @return string
 196       */
 197      public function get_visible_name() {
 198          return $this->cm->get_formatted_name().' ('.$this->cm->get_module_type_name().')';
 199      }
 200  
 201      /**
 202       * Whether or not files or directories can be added
 203       *
 204       * @return bool
 205       */
 206      public function is_writable() {
 207          return false;
 208      }
 209  
 210      /**
 211       * Whether or not this is an emtpy area
 212       *
 213       * @return bool
 214       */
 215      public function is_empty_area() {
 216          if ($child = $this->get_area_backup(0, '/', '.')) {
 217              if (!$child->is_empty_area()) {
 218                  return false;
 219              }
 220          }
 221          if ($child = $this->get_area_intro(0, '/', '.')) {
 222              if (!$child->is_empty_area()) {
 223                  return false;
 224              }
 225          }
 226  
 227          foreach ($this->areas as $area=>$desctiption) {
 228              if ($child = $this->get_file_info('mod_'.$this->modname, $area, null, null, null)) {
 229                  if (!$child->is_empty_area()) {
 230                      return false;
 231                  }
 232              }
 233          }
 234  
 235          return true;
 236      }
 237  
 238      /**
 239       * Whether or not this is a directory
 240       *
 241       * @return bool
 242       */
 243      public function is_directory() {
 244          return true;
 245      }
 246  
 247      /**
 248       * Returns list of children.
 249       *
 250       * @return array of file_info instances
 251       */
 252      public function get_children() {
 253          return $this->get_filtered_children('*', false, true);
 254      }
 255  
 256      /**
 257       * Help function to return files matching extensions or their count
 258       *
 259       * @param string|array $extensions, either '*' or array of lowercase extensions, i.e. array('.gif','.jpg')
 260       * @param bool|int $countonly if false returns the children, if an int returns just the
 261       *    count of children but stops counting when $countonly number of children is reached
 262       * @param bool $returnemptyfolders if true returns items that don't have matching files inside
 263       * @return array|int array of file_info instances or the count
 264       */
 265      private function get_filtered_children($extensions = '*', $countonly = false, $returnemptyfolders = false) {
 266          global $DB;
 267          // prepare list of areas including intro and backup
 268          $areas = array(
 269              array('mod_'.$this->modname, 'intro'),
 270              array('backup', 'activity')
 271          );
 272          foreach ($this->areas as $area => $desctiption) {
 273              $areas[] = array('mod_'.$this->modname, $area);
 274          }
 275  
 276          $params1 = array('contextid' => $this->context->id, 'emptyfilename' => '.');
 277          list($sql2, $params2) = $this->build_search_files_sql($extensions);
 278          $children = array();
 279          foreach ($areas as $area) {
 280              if (!$returnemptyfolders) {
 281                  // fast pre-check if there are any files in the filearea
 282                  $params1['component'] = $area[0];
 283                  $params1['filearea'] = $area[1];
 284                  if (!$DB->record_exists_sql('SELECT 1 from {files}
 285                          WHERE contextid = :contextid
 286                          AND filename <> :emptyfilename
 287                          AND component = :component
 288                          AND filearea = :filearea '.$sql2,
 289                          array_merge($params1, $params2))) {
 290                      continue;
 291                  }
 292              }
 293              if ($child = $this->get_file_info($area[0], $area[1], null, null, null)) {
 294                  if ($returnemptyfolders || $child->count_non_empty_children($extensions)) {
 295                      $children[] = $child;
 296                      if ($countonly !== false && count($children) >= $countonly) {
 297                          break;
 298                      }
 299                  }
 300              }
 301          }
 302          if ($countonly !== false) {
 303              return count($children);
 304          }
 305          return $children;
 306      }
 307  
 308      /**
 309       * Returns list of children which are either files matching the specified extensions
 310       * or folders that contain at least one such file.
 311       *
 312       * @param string|array $extensions either '*' or array of lowercase extensions, i.e. array('.gif','.jpg')
 313       * @return array of file_info instances
 314       */
 315      public function get_non_empty_children($extensions = '*') {
 316          if ($this->nonemptychildren !== null) {
 317              return $this->nonemptychildren;
 318          }
 319          $this->nonemptychildren = $this->get_filtered_children($extensions);
 320          return $this->nonemptychildren;
 321      }
 322  
 323      /**
 324       * Returns the number of children which are either files matching the specified extensions
 325       * or folders containing at least one such file.
 326       *
 327       * @param string|array $extensions for example '*' or array('.gif','.jpg')
 328       * @param int $limit stop counting after at least $limit non-empty children are found
 329       * @return int
 330       */
 331      public function count_non_empty_children($extensions = '*', $limit = 1) {
 332          if ($this->nonemptychildren !== null) {
 333              return count($this->nonemptychildren);
 334          }
 335          return $this->get_filtered_children($extensions, $limit);
 336      }
 337  
 338      /**
 339       * Returns parent file_info instance
 340       *
 341       * @return file_info|null file_info or null for root
 342       */
 343      public function get_parent() {
 344          $parent = $this->context->get_parent_context();
 345          return $this->browser->get_file_info($parent);
 346      }
 347  }