lib/filebrowser/file_info_context_module.php

   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 }