lib/pagelib.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  * This file contains the moodle_page class. There is normally a single instance
  19  * of this class in the $PAGE global variable. This class is a central repository
  20  * of information about the page we are building up to send back to the user.
  21  *
  22  * @package core
  23  * @category page
  24  * @copyright  1999 onwards Martin Dougiamas  {@link http://moodle.com}
  25  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  26  */
  27
  28 defined('MOODLE_INTERNAL') || die();
  29
  30 /**
  31  * $PAGE is a central store of information about the current page we are
  32  * generating in response to the user's request.
  33  *
  34  * It does not do very much itself
  35  * except keep track of information, however, it serves as the access point to
  36  * some more significant components like $PAGE->theme, $PAGE->requires,
  37  * $PAGE->blocks, etc.
  38  *
  39  * @copyright 2009 Tim Hunt
  40  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  41  * @since Moodle 2.0
  42  * @package core
  43  * @category page
  44  *
  45  * The following properties are alphabetical. Please keep it that way so that its
  46  * easy to maintain.
  47  *
  48  * @property-read string $activityname The type of activity we are in, for example 'forum' or 'quiz'.
  49  *      Will be null if this page is not within a module.
  50  * @property-read stdClass $activityrecord The row from the activities own database table (for example
  51  *      the forum or quiz table) that this page belongs to. Will be null
  52  *      if this page is not within a module.
  53  * @property-read array $alternativeversions Mime type => object with ->url and ->title.
  54  * @property-read block_manager $blocks The blocks manager object for this page.
  55  * @property-read array $blockmanipulations
  56  * @property-read string $bodyclasses A string to use within the class attribute on the body tag.
  57  * @property-read string $bodyid A string to use as the id of the body tag.
  58  * @property-read string $button The HTML to go where the Turn editing on button normally goes.
  59  * @property-read bool $cacheable Defaults to true. Set to false to stop the page being cached at all.
  60  * @property-read array $categories An array of all the categories the page course belongs to,
  61  *      starting with the immediately containing category, and working out to
  62  *      the top-level category. This may be the empty array if we are in the
  63  *      front page course.
  64  * @property-read mixed $category The category that the page course belongs to.
  65  * @property-read cm_info $cm The course_module that this page belongs to. Will be null
  66  *      if this page is not within a module. This is a full cm object, as loaded
  67  *      by get_coursemodule_from_id or get_coursemodule_from_instance,
  68  *      so the extra modname and name fields are present.
  69  * @property-read context $context The main context to which this page belongs.
  70  * @property-read stdClass $course The current course that we are inside - a row from the
  71  *      course table. (Also available as $COURSE global.) If we are not inside
  72  *      an actual course, this will be the site course.
  73  * @property-read string $devicetypeinuse The name of the device type in use
  74  * @property-read string $docspath The path to the Moodle docs for this page.
  75  * @property-read string $focuscontrol The id of the HTML element to be focused when the page has loaded.
  76  * @property-read bool $headerprinted True if the page header has already been printed.
  77  * @property-read string $heading The main heading that should be displayed at the top of the <body>.
  78  * @property-read string $headingmenu The menu (or actions) to display in the heading
  79  * @property-read array $layout_options An arrays with options for the layout file.
  80  * @property-read array $legacythemeinuse True if the legacy browser theme is in use.
  81  * @property-read navbar $navbar The navbar object used to display the navbar
  82  * @property-read global_navigation $navigation The navigation structure for this page.
  83  * @property-read xhtml_container_stack $opencontainers Tracks XHTML tags on this page that have been opened but not closed.
  84  *      mainly for internal use by the rendering code.
  85  * @property-read string $pagelayout The general type of page this is. For example 'normal', 'popup', 'home'.
  86  *      Allows the theme to display things differently, if it wishes to.
  87  * @property-read string $pagetype The page type string, should be used as the id for the body tag in the theme.
  88  * @property-read int $periodicrefreshdelay The periodic refresh delay to use with meta refresh
  89  * @property-read page_requirements_manager $requires Tracks the JavaScript, CSS files, etc. required by this page.
  90  * @property-read string $requestip The IP address of the current request, null if unknown.
  91  * @property-read string $requestorigin The type of request 'web', 'ws', 'cli', 'restore', etc.
  92  * @property-read settings_navigation $settingsnav The settings navigation
  93  * @property-read int $state One of the STATE_... constants
  94  * @property-read string $subpage The subpage identifier, if any.
  95  * @property-read theme_config $theme The theme for this page.
  96  * @property-read string $title The title that should go in the <head> section of the HTML of this page.
  97  * @property-read moodle_url $url The moodle url object for this page.
  98  */
  99 class moodle_page {
 100
 101     /** The state of the page before it has printed the header **/
 102     const STATE_BEFORE_HEADER = 0;
 103
 104     /** The state the page is in temporarily while the header is being printed **/
 105     const STATE_PRINTING_HEADER = 1;
 106
 107     /** The state the page is in while content is presumably being printed **/
 108     const STATE_IN_BODY = 2;
 109
 110     /**
 111      * The state the page is when the footer has been printed and its function is
 112      * complete.
 113      */
 114     const STATE_DONE = 3;
 115
 116     /**
 117      * @var int The current state of the page. The state a page is within
 118      * determines what actions are possible for it.
 119      */
 120     protected $_state = self::STATE_BEFORE_HEADER;
 121
 122     /**
 123      * @var stdClass The course currently associated with this page.
 124      * If not has been provided the front page course is used.
 125      */
 126     protected $_course = null;
 127
 128     /**
 129      * @var cm_info If this page belongs to a module, this is the cm_info module
 130      * description object.
 131      */
 132     protected $_cm = null;
 133
 134     /**
 135      * @var stdClass If $_cm is not null, then this will hold the corresponding
 136      * row from the modname table. For example, if $_cm->modname is 'quiz', this
 137      * will be a row from the quiz table.
 138      */
 139     protected $_module = null;
 140
 141     /**
 142      * @var context The context that this page belongs to.
 143      */
 144     protected $_context = null;
 145
 146     /**
 147      * @var array This holds any categories that $_course belongs to, starting with the
 148      * particular category it belongs to, and working out through any parent
 149      * categories to the top level. These are loaded progressively, if needed.
 150      * There are three states. $_categories = null initially when nothing is
 151      * loaded; $_categories = array($id => $cat, $parentid => null) when we have
 152      * loaded $_course->category, but not any parents; and a complete array once
 153      * everything is loaded.
 154      */
 155     protected $_categories = null;
 156
 157     /**
 158      * @var array An array of CSS classes that should be added to the body tag in HTML.
 159      */
 160     protected $_bodyclasses = array();
 161
 162     /**
 163      * @var string The title for the page. Used within the title tag in the HTML head.
 164      */
 165     protected $_title = '';
 166
 167     /**
 168      * @var string The string to use as the heading of the page. Shown near the top of the
 169      * page within most themes.
 170      */
 171     protected $_heading = '';
 172
 173     /**
 174      * @var string The pagetype is used to describe the page and defaults to a representation
 175      * of the physical path to the page e.g. my-index, mod-quiz-attempt
 176      */
 177     protected $_pagetype = null;
 178
 179     /**
 180      * @var string The pagelayout to use when displaying this page. The
 181      * pagelayout needs to have been defined by the theme in use, or one of its
 182      * parents. By default base is used however standard is the more common layout.
 183      * Note that this gets automatically set by core during operations like
 184      * require_login.
 185      */
 186     protected $_pagelayout = 'base';
 187
 188     /**
 189      * @var array List of theme layout options, these are ignored by core.
 190      * To be used in individual theme layout files only.
 191      */
 192     protected $_layout_options = null;
 193
 194     /**
 195      * @var string An optional arbitrary parameter that can be set on pages where the context
 196      * and pagetype is not enough to identify the page.
 197      */
 198     protected $_subpage = '';
 199
 200     /**
 201      * @var string Set a different path to use for the 'Moodle docs for this page' link.
 202      * By default, it uses the path of the file for instance mod/quiz/attempt.
 203      */
 204     protected $_docspath = null;
 205
 206     /**
 207      * @var string A legacy class that will be added to the body tag
 208      */
 209     protected $_legacyclass = null;
 210
 211     /**
 212      * @var moodle_url The URL for this page. This is mandatory and must be set
 213      * before output is started.
 214      */
 215     protected $_url = null;
 216
 217     /**
 218      * @var array An array of links to alternative versions of this page.
 219      * Primarily used for RSS versions of the current page.
 220      */
 221     protected $_alternateversions = array();
 222
 223     /**
 224      * @var block_manager The blocks manager for this page. It is responsible for
 225      * the blocks and there content on this page.
 226      */
 227     protected $_blocks = null;
 228
 229     /**
 230      * @var page_requirements_manager Page requirements manager. It is responsible
 231      * for all JavaScript and CSS resources required by this page.
 232      */
 233     protected $_requires = null;
 234
 235     /**
 236      * @var string The capability required by the user in order to edit blocks
 237      * and block settings on this page.
 238      */
 239     protected $_blockseditingcap = 'moodle/site:manageblocks';
 240
 241     /**
 242      * @var bool An internal flag to record when block actions have been processed.
 243      * Remember block actions occur on the current URL and it is important that
 244      * even they are never executed more than once.
 245      */
 246     protected $_block_actions_done = false;
 247
 248     /**
 249      * @var array An array of any other capabilities the current user must have
 250      * in order to editing the page and/or its content (not just blocks).
 251      */
 252     protected $_othereditingcaps = array();
 253
 254     /**
 255      * @var bool Sets whether this page should be cached by the browser or not.
 256      * If it is set to true (default) the page is served with caching headers.
 257      */
 258     protected $_cacheable = true;
 259
 260     /**
 261      * @var string Can be set to the ID of an element on the page, if done that
 262      * element receives focus when the page loads.
 263      */
 264     protected $_focuscontrol = '';
 265
 266     /**
 267      * @var string HTML to go where the turn on editing button is located. This
 268      * is nearly a legacy item and not used very often any more.
 269      */
 270     protected $_button = '';
 271
 272     /**
 273      * @var theme_config The theme to use with this page. This has to be properly
 274      * initialised via {@link moodle_page::initialise_theme_and_output()} which
 275      * happens magically before any operation that requires it.
 276      */
 277     protected $_theme = null;
 278
 279     /**
 280      * @var global_navigation Contains the global navigation structure.
 281      */
 282     protected $_navigation = null;
 283
 284     /**
 285      * @var settings_navigation Contains the settings navigation structure.
 286      */
 287     protected $_settingsnav = null;
 288
 289     /**
 290      * @var navbar Contains the navbar structure.
 291      */
 292     protected $_navbar = null;
 293
 294     /**
 295      * @var string The menu (or actions) to display in the heading.
 296      */
 297     protected $_headingmenu = null;
 298
 299     /**
 300      * @var array stack trace. Then the theme is initialised, we save the stack
 301      * trace, for use in error messages.
 302      */
 303     protected $_wherethemewasinitialised = null;
 304
 305     /**
 306      * @var xhtml_container_stack Tracks XHTML tags on this page that have been
 307      * opened but not closed.
 308      */
 309     protected $_opencontainers;
 310
 311     /**
 312      * @var int Sets the page to refresh after a given delay (in seconds) using
 313      * meta refresh in {@link standard_head_html()} in outputlib.php
 314      * If set to null(default) the page is not refreshed
 315      */
 316     protected $_periodicrefreshdelay = null;
 317
 318     /**
 319      * @var array Associative array of browser shortnames (as used by check_browser_version)
 320      * and their minimum required versions
 321      */
 322     protected $_legacybrowsers = array('MSIE' => 6.0);
 323
 324     /**
 325      * @var string Is set to the name of the device type in use.
 326      * This will we worked out when it is first used.
 327      */
 328     protected $_devicetypeinuse = null;
 329
 330     /**
 331      * @var bool Used to determine if HTTPS should be required for login.
 332      */
 333     protected $_https_login_required = false;
 334
 335     /**
 336      * @var bool Determines if popup notifications allowed on this page.
 337      * Code such as the quiz module disables popup notifications in situations
 338      * such as upgrading or completing a quiz.
 339      */
 340     protected $_popup_notification_allowed = true;
 341
 342     // Magic getter methods =============================================================
 343     // Due to the __get magic below, you normally do not call these as $PAGE->magic_get_x
 344     // methods, but instead use the $PAGE->x syntax.
 345
 346     /**
 347      * Please do not call this method directly, use the ->state syntax. {@link moodle_page::__get()}.
 348      * @return integer one of the STATE_XXX constants. You should not normally need
 349      * to use this in your code. It is intended for internal use by this class
 350      * and its friends like print_header, to check that everything is working as
 351      * expected. Also accessible as $PAGE->state.
 352      */
 353     protected function magic_get_state() {
 354         return $this->_state;
 355     }
 356
 357     /**
 358      * Please do not call this method directly, use the ->headerprinted syntax. {@link moodle_page::__get()}.
 359      * @return bool has the header already been printed?
 360      */
 361     protected function magic_get_headerprinted() {
 362         return $this->_state >= self::STATE_IN_BODY;
 363     }
 364
 365     /**
 366      * Please do not call this method directly, use the ->course syntax. {@link moodle_page::__get()}.
 367      * @return stdClass the current course that we are inside - a row from the
 368      * course table. (Also available as $COURSE global.) If we are not inside
 369      * an actual course, this will be the site course.
 370      */
 371     protected function magic_get_course() {
 372         global $SITE;
 373         if (is_null($this->_course)) {
 374             return $SITE;
 375         }
 376         return $this->_course;
 377     }
 378
 379     /**
 380      * Please do not call this method directly, use the ->cm syntax. {@link moodle_page::__get()}.
 381      * @return cm_info the course_module that this page belongs to. Will be null
 382      * if this page is not within a module. This is a full cm object, as loaded
 383      * by get_coursemodule_from_id or get_coursemodule_from_instance,
 384      * so the extra modname and name fields are present.
 385      */
 386     protected function magic_get_cm() {
 387         return $this->_cm;
 388     }
 389
 390     /**
 391      * Please do not call this method directly, use the ->activityrecord syntax. {@link moodle_page::__get()}.
 392      * @return stdClass the row from the activities own database table (for example
 393      * the forum or quiz table) that this page belongs to. Will be null
 394      * if this page is not within a module.
 395      */
 396     protected function magic_get_activityrecord() {
 397         if (is_null($this->_module) && !is_null($this->_cm)) {
 398             $this->load_activity_record();
 399         }
 400         return $this->_module;
 401     }
 402
 403     /**
 404      * Please do not call this method directly, use the ->activityname syntax. {@link moodle_page::__get()}.
 405      * @return string the The type of activity we are in, for example 'forum' or 'quiz'.
 406      * Will be null if this page is not within a module.
 407      */
 408     protected function magic_get_activityname() {
 409         if (is_null($this->_cm)) {
 410             return null;
 411         }
 412         return $this->_cm->modname;
 413     }
 414
 415     /**
 416      * Please do not call this method directly, use the ->category syntax. {@link moodle_page::__get()}.
 417      * @return stdClass the category that the page course belongs to. If there isn't one
 418      * (that is, if this is the front page course) returns null.
 419      */
 420     protected function magic_get_category() {
 421         $this->ensure_category_loaded();
 422         if (!empty($this->_categories)) {
 423             return reset($this->_categories);
 424         } else {
 425             return null;
 426         }
 427     }
 428
 429     /**
 430      * Please do not call this method directly, use the ->categories syntax. {@link moodle_page::__get()}.
 431      * @return array an array of all the categories the page course belongs to,
 432      * starting with the immediately containing category, and working out to
 433      * the top-level category. This may be the empty array if we are in the
 434      * front page course.
 435      */
 436     protected function magic_get_categories() {
 437         $this->ensure_categories_loaded();
 438         return $this->_categories;
 439     }
 440
 441     /**
 442      * Please do not call this method directly, use the ->context syntax. {@link moodle_page::__get()}.
 443      * @return context the main context to which this page belongs.
 444      */
 445     protected function magic_get_context() {
 446         if (is_null($this->_context)) {
 447             if (CLI_SCRIPT or NO_MOODLE_COOKIES) {
 448                 // Cli scripts work in system context, do not annoy devs with debug info.
 449                 // Very few scripts do not use cookies, we can safely use system as default context there.
 450             } else {
 451                 debugging('Coding problem: $PAGE->context was not set. You may have forgotten '
 452                     .'to call require_login() or $PAGE->set_context(). The page may not display '
 453                     .'correctly as a result');
 454             }
 455             $this->_context = context_system::instance();
 456         }
 457         return $this->_context;
 458     }
 459
 460     /**
 461      * Please do not call this method directly, use the ->pagetype syntax. {@link moodle_page::__get()}.
 462      * @return string e.g. 'my-index' or 'mod-quiz-attempt'.
 463      */
 464     protected function magic_get_pagetype() {
 465         global $CFG;
 466         if (is_null($this->_pagetype) || isset($CFG->pagepath)) {
 467             $this->initialise_default_pagetype();
 468         }
 469         return $this->_pagetype;
 470     }
 471
 472     /**
 473      * Please do not call this method directly, use the ->pagetype syntax. {@link moodle_page::__get()}.
 474      * @return string The id to use on the body tag, uses {@link magic_get_pagetype()}.
 475      */
 476     protected function magic_get_bodyid() {
 477         return 'page-'.$this->pagetype;
 478     }
 479
 480     /**
 481      * Please do not call this method directly, use the ->pagelayout syntax. {@link moodle_page::__get()}.
 482      * @return string the general type of page this is. For example 'standard', 'popup', 'home'.
 483      *      Allows the theme to display things differently, if it wishes to.
 484      */
 485     protected function magic_get_pagelayout() {
 486         return $this->_pagelayout;
 487     }
 488
 489     /**
 490      * Please do not call this method directly, use the ->layout_options syntax. {@link moodle_page::__get()}.
 491      * @return array returns arrays with options for layout file
 492      */
 493     protected function magic_get_layout_options() {
 494         if (!is_array($this->_layout_options)) {
 495             $this->_layout_options = $this->_theme->pagelayout_options($this->pagelayout);
 496         }
 497         return $this->_layout_options;
 498     }
 499
 500     /**
 501      * Please do not call this method directly, use the ->subpage syntax. {@link moodle_page::__get()}.
 502      * @return string The subpage identifier, if any.
 503      */
 504     protected function magic_get_subpage() {
 505         return $this->_subpage;
 506     }
 507
 508     /**
 509      * Please do not call this method directly, use the ->bodyclasses syntax. {@link moodle_page::__get()}.
 510      * @return string the class names to put on the body element in the HTML.
 511      */
 512     protected function magic_get_bodyclasses() {
 513         return implode(' ', array_keys($this->_bodyclasses));
 514     }
 515
 516     /**
 517      * Please do not call this method directly, use the ->title syntax. {@link moodle_page::__get()}.
 518      * @return string the title that should go in the <head> section of the HTML of this page.
 519      */
 520     protected function magic_get_title() {
 521         return $this->_title;
 522     }
 523
 524     /**
 525      * Please do not call this method directly, use the ->heading syntax. {@link moodle_page::__get()}.
 526      * @return string the main heading that should be displayed at the top of the <body>.
 527      */
 528     protected function magic_get_heading() {
 529         return $this->_heading;
 530     }
 531
 532     /**
 533      * Please do not call this method directly, use the ->heading syntax. {@link moodle_page::__get()}.
 534      * @return string The menu (or actions) to display in the heading
 535      */
 536     protected function magic_get_headingmenu() {
 537         return $this->_headingmenu;
 538     }
 539
 540     /**
 541      * Please do not call this method directly, use the ->docspath syntax. {@link moodle_page::__get()}.
 542      * @return string the path to the Moodle docs for this page.
 543      */
 544     protected function magic_get_docspath() {
 545         if (is_string($this->_docspath)) {
 546             return $this->_docspath;
 547         } else {
 548             return str_replace('-', '/', $this->pagetype);
 549         }
 550     }
 551
 552     /**
 553      * Please do not call this method directly, use the ->url syntax. {@link moodle_page::__get()}.
 554      * @return moodle_url the clean URL required to load the current page. (You
 555      * should normally use this in preference to $ME or $FULLME.)
 556      */
 557     protected function magic_get_url() {
 558         global $FULLME;
 559         if (is_null($this->_url)) {
 560             debugging('This page did not call $PAGE->set_url(...). Using '.s($FULLME), DEBUG_DEVELOPER);
 561             $this->_url = new moodle_url($FULLME);
 562             // Make sure the guessed URL cannot lead to dangerous redirects.
 563             $this->_url->remove_params('sesskey');
 564         }
 565         return new moodle_url($this->_url); // Return a clone for safety.
 566     }
 567
 568     /**
 569      * The list of alternate versions of this page.
 570      * @return array mime type => object with ->url and ->title.
 571      */
 572     protected function magic_get_alternateversions() {
 573         return $this->_alternateversions;
 574     }
 575
 576     /**
 577      * Please do not call this method directly, use the ->blocks syntax. {@link moodle_page::__get()}.
 578      * @return block_manager the blocks manager object for this page.
 579      */
 580     protected function magic_get_blocks() {
 581         global $CFG;
 582         if (is_null($this->_blocks)) {
 583             if (!empty($CFG->blockmanagerclass)) {
 584                 if (!empty($CFG->blockmanagerclassfile)) {
 585                     require_once($CFG->blockmanagerclassfile);
 586                 }
 587                 $classname = $CFG->blockmanagerclass;
 588             } else {
 589                 $classname = 'block_manager';
 590             }
 591             $this->_blocks = new $classname($this);
 592         }
 593         return $this->_blocks;
 594     }
 595
 596     /**
 597      * Please do not call this method directly, use the ->requires syntax. {@link moodle_page::__get()}.
 598      * @return page_requirements_manager tracks the JavaScript, CSS files, etc. required by this page.
 599      */
 600     protected function magic_get_requires() {
 601         if (is_null($this->_requires)) {
 602             $this->_requires = new page_requirements_manager();
 603         }
 604         return $this->_requires;
 605     }
 606
 607     /**
 608      * Please do not call this method directly, use the ->cacheable syntax. {@link moodle_page::__get()}.
 609      * @return bool can this page be cached by the user's browser.
 610      */
 611     protected function magic_get_cacheable() {
 612         return $this->_cacheable;
 613     }
 614
 615     /**
 616      * Please do not call this method directly, use the ->focuscontrol syntax. {@link moodle_page::__get()}.
 617      * @return string the id of the HTML element to be focused when the page has loaded.
 618      */
 619     protected function magic_get_focuscontrol() {
 620         return $this->_focuscontrol;
 621     }
 622
 623     /**
 624      * Please do not call this method directly, use the ->button syntax. {@link moodle_page::__get()}.
 625      * @return string the HTML to go where the Turn editing on button normally goes.
 626      */
 627     protected function magic_get_button() {
 628         return $this->_button;
 629     }
 630
 631     /**
 632      * Please do not call this method directly, use the ->theme syntax. {@link moodle_page::__get()}.
 633      * @return theme_config the initialised theme for this page.
 634      */
 635     protected function magic_get_theme() {
 636         if (is_null($this->_theme)) {
 637             $this->initialise_theme_and_output();
 638         }
 639         return $this->_theme;
 640     }
 641
 642     /**
 643      * Returns an array of minipulations or false if there are none to make.
 644      *
 645      * @since Moodle 2.5.1 2.6
 646      * @return bool|array
 647      */
 648     protected function magic_get_blockmanipulations() {
 649         if (!right_to_left()) {
 650             return false;
 651         }
 652         if (is_null($this->_theme)) {
 653             $this->initialise_theme_and_output();
 654         }
 655         return $this->_theme->blockrtlmanipulations;
 656     }
 657
 658     /**
 659      * Please do not call this method directly, use the ->devicetypeinuse syntax. {@link moodle_page::__get()}.
 660      * @return string The device type being used.
 661      */
 662     protected function magic_get_devicetypeinuse() {
 663         if (empty($this->_devicetypeinuse)) {
 664             $this->_devicetypeinuse = core_useragent::get_user_device_type();
 665         }
 666         return $this->_devicetypeinuse;
 667     }
 668
 669     /**
 670      * Please do not call this method directly use the ->periodicrefreshdelay syntax
 671      * {@link moodle_page::__get()}
 672      * @return int The periodic refresh delay to use with meta refresh
 673      */
 674     protected function magic_get_periodicrefreshdelay() {
 675         return $this->_periodicrefreshdelay;
 676     }
 677
 678     /**
 679      * Please do not call this method directly use the ->opencontainers syntax. {@link moodle_page::__get()}
 680      * @return xhtml_container_stack tracks XHTML tags on this page that have been opened but not closed.
 681      *      mainly for internal use by the rendering code.
 682      */
 683     protected function magic_get_opencontainers() {
 684         if (is_null($this->_opencontainers)) {
 685             $this->_opencontainers = new xhtml_container_stack();
 686         }
 687         return $this->_opencontainers;
 688     }
 689
 690     /**
 691      * Return the navigation object
 692      * @return global_navigation
 693      */
 694     protected function magic_get_navigation() {
 695         if ($this->_navigation === null) {
 696             $this->_navigation = new global_navigation($this);
 697         }
 698         return $this->_navigation;
 699     }
 700
 701     /**
 702      * Return a navbar object
 703      * @return navbar
 704      */
 705     protected function magic_get_navbar() {
 706         if ($this->_navbar === null) {
 707             $this->_navbar = new navbar($this);
 708         }
 709         return $this->_navbar;
 710     }
 711
 712     /**
 713      * Returns the settings navigation object
 714      * @return settings_navigation
 715      */
 716     protected function magic_get_settingsnav() {
 717         if ($this->_settingsnav === null) {
 718             $this->_settingsnav = new settings_navigation($this);
 719             $this->_settingsnav->initialise();
 720         }
 721         return $this->_settingsnav;
 722     }
 723
 724     /**
 725      * Returns request IP address.
 726      *
 727      * @return string IP address or null if unknown
 728      */
 729     protected function magic_get_requestip() {
 730         return getremoteaddr(null);
 731     }
 732
 733     /**
 734      * Returns the origin of current request.
 735      *
 736      * Note: constants are not required because we need to use these values in logging and reports.
 737      *
 738      * @return string 'web', 'ws', 'cli', 'restore', etc.
 739      */
 740     protected function magic_get_requestorigin() {
 741         if (class_exists('restore_controller', false) && restore_controller::is_executing()) {
 742             return 'restore';
 743         }
 744
 745         if (WS_SERVER) {
 746             return 'ws';
 747         }
 748
 749         if (CLI_SCRIPT) {
 750             return 'cli';
 751         }
 752
 753         return 'web';
 754     }
 755
 756     /**
 757      * PHP overloading magic to make the $PAGE->course syntax work by redirecting
 758      * it to the corresponding $PAGE->magic_get_course() method if there is one, and
 759      * throwing an exception if not.
 760      *
 761      * @param string $name property name
 762      * @return mixed
 763      * @throws coding_exception
 764      */
 765     public function __get($name) {
 766         $getmethod = 'magic_get_' . $name;
 767         if (method_exists($this, $getmethod)) {
 768             return $this->$getmethod();
 769         } else {
 770             throw new coding_exception('Unknown property ' . $name . ' of $PAGE.');
 771         }
 772     }
 773
 774     /**
 775      * PHP overloading magic to catch obvious coding errors.
 776      *
 777      * This method has been created to catch obvious coding errors where the
 778      * developer has tried to set a page property using $PAGE->key = $value.
 779      * In the moodle_page class all properties must be set using the appropriate
 780      * $PAGE->set_something($value) method.
 781      *
 782      * @param string $name property name
 783      * @param mixed $value Value
 784      * @return void Throws exception if field not defined in page class
 785      * @throws coding_exception
 786      */
 787     public function __set($name, $value) {
 788         if (method_exists($this, 'set_' . $name)) {
 789             throw new coding_exception('Invalid attempt to modify page object', "Use \$PAGE->set_$name() instead.");
 790         } else {
 791             throw new coding_exception('Invalid attempt to modify page object', "Unknown property $name");
 792         }
 793     }
 794
 795     // Other information getting methods ==========================================.
 796
 797     /**
 798      * Returns instance of page renderer
 799      *
 800      * @param string $component name such as 'core', 'mod_forum' or 'qtype_multichoice'.
 801      * @param string $subtype optional subtype such as 'news' resulting to 'mod_forum_news'
 802      * @param string $target one of rendering target constants
 803      * @return renderer_base
 804      */
 805     public function get_renderer($component, $subtype = null, $target = null) {
 806         if ($this->pagelayout === 'maintenance') {
 807             // If the page is using the maintenance layout then we're going to force target to maintenance.
 808             // This leads to a special core renderer that is designed to block access to API's that are likely unavailable for this
 809             // page layout.
 810             $target = RENDERER_TARGET_MAINTENANCE;
 811         }
 812         return $this->magic_get_theme()->get_renderer($this, $component, $subtype, $target);
 813     }
 814
 815     /**
 816      * Checks to see if there are any items on the navbar object
 817      *
 818      * @return bool true if there are, false if not
 819      */
 820     public function has_navbar() {
 821         if ($this->_navbar === null) {
 822             $this->_navbar = new navbar($this);
 823         }
 824         return $this->_navbar->has_items();
 825     }
 826
 827     /**
 828      * Should the current user see this page in editing mode.
 829      * That is, are they allowed to edit this page, and are they currently in
 830      * editing mode.
 831      * @return bool
 832      */
 833     public function user_is_editing() {
 834         global $USER;
 835         return !empty($USER->editing) && $this->user_allowed_editing();
 836     }
 837
 838     /**
 839      * Does the user have permission to edit blocks on this page.
 840      * @return bool
 841      */
 842     public function user_can_edit_blocks() {
 843         return has_capability($this->_blockseditingcap, $this->_context);
 844     }
 845
 846     /**
 847      * Does the user have permission to see this page in editing mode.
 848      * @return bool
 849      */
 850     public function user_allowed_editing() {
 851         return has_any_capability($this->all_editing_caps(), $this->_context);
 852     }
 853
 854     /**
 855      * Get a description of this page. Normally displayed in the footer in developer debug mode.
 856      * @return string
 857      */
 858     public function debug_summary() {
 859         $summary = '';
 860         $summary .= 'General type: ' . $this->pagelayout . '. ';
 861         if (!during_initial_install()) {
 862             $summary .= 'Context ' . $this->context->get_context_name() . ' (context id ' . $this->_context->id . '). ';
 863         }
 864         $summary .= 'Page type ' . $this->pagetype .  '. ';
 865         if ($this->subpage) {
 866             $summary .= 'Sub-page ' . $this->subpage .  '. ';
 867         }
 868         return $summary;
 869     }
 870
 871     // Setter methods =============================================================.
 872
 873     /**
 874      * Set the state.
 875      *
 876      * The state must be one of that STATE_... constants, and the state is only allowed to advance one step at a time.
 877      *
 878      * @param int $state The new state.
 879      * @throws coding_exception
 880      */
 881     public function set_state($state) {
 882         if ($state != $this->_state + 1 || $state > self::STATE_DONE) {
 883             throw new coding_exception('Invalid state passed to moodle_page::set_state. We are in state ' .
 884                     $this->_state . ' and state ' . $state . ' was requested.');
 885         }
 886
 887         if ($state == self::STATE_PRINTING_HEADER) {
 888             $this->starting_output();
 889         }
 890
 891         $this->_state = $state;
 892     }
 893
 894     /**
 895      * Set the current course. This sets both $PAGE->course and $COURSE. It also
 896      * sets the right theme and locale.
 897      *
 898      * Normally you don't need to call this function yourself, require_login will
 899      * call it for you if you pass a $course to it. You can use this function
 900      * on pages that do need to call require_login().
 901      *
 902      * Sets $PAGE->context to the course context, if it is not already set.
 903      *
 904      * @param stdClass $course the course to set as the global course.
 905      * @throws coding_exception
 906      */
 907     public function set_course($course) {
 908         global $COURSE, $PAGE, $CFG, $SITE;
 909
 910         if (empty($course->id)) {
 911             throw new coding_exception('$course passed to moodle_page::set_course does not look like a proper course object.');
 912         }
 913
 914         $this->ensure_theme_not_set();
 915
 916         if (!empty($this->_course->id) && $this->_course->id != $course->id) {
 917             $this->_categories = null;
 918         }
 919
 920         $this->_course = clone($course);
 921
 922         if ($this === $PAGE) {
 923             $COURSE = $this->_course;
 924             moodle_setlocale();
 925         }
 926
 927         if (!$this->_context) {
 928             $this->set_context(context_course::instance($this->_course->id));
 929         }
 930
 931         // Notify course format that this page is set for the course.
 932         if ($this->_course->id != $SITE->id) {
 933             require_once($CFG->dirroot.'/course/lib.php');
 934             $courseformat = course_get_format($this->_course);
 935             $this->add_body_class('format-'. $courseformat->get_format());
 936             $courseformat->page_set_course($this);
 937         } else {
 938             $this->add_body_class('format-site');
 939         }
 940     }
 941
 942     /**
 943      * Set the main context to which this page belongs.
 944      *
 945      * @param context $context a context object. You normally get this with context_xxxx::instance().
 946      */
 947     public function set_context($context) {
 948         if ($context === null) {
 949             // Extremely ugly hack which sets context to some value in order to prevent warnings,
 950             // use only for core error handling!!!!
 951             if (!$this->_context) {
 952                 $this->_context = context_system::instance();
 953             }
 954             return;
 955         }
 956
 957         // Ideally we should set context only once.
 958         if (isset($this->_context) && $context->id !== $this->_context->id) {
 959             $current = $this->_context->contextlevel;
 960             if ($current == CONTEXT_SYSTEM or $current == CONTEXT_COURSE) {
 961                 // Hmm - not ideal, but it might produce too many warnings due to the design of require_login.
 962             } else if ($current == CONTEXT_MODULE and ($parentcontext = $context->get_parent_context()) and
 963                 $this->_context->id == $parentcontext->id) {
 964                 // Hmm - most probably somebody did require_login() and after that set the block context.
 965             } else {
 966                 // We do not want devs to do weird switching of context levels on the fly because we might have used
 967                 // the context already such as in text filter in page title.
 968                 // This is explicitly allowed for webservices though which may
 969                 // call "external_api::validate_context on many contexts in a single request.
 970                 if (!WS_SERVER) {
 971                     debugging("Coding problem: unsupported modification of PAGE->context from {$current} to {$context->contextlevel}");
 972                 }
 973             }
 974         }
 975
 976         $this->_context = $context;
 977     }
 978
 979     /**
 980      * The course module that this page belongs to (if it does belong to one).
 981      *
 982      * @param stdClass|cm_info $cm a record from course_modules table or cm_info from get_fast_modinfo().
 983      * @param stdClass $course
 984      * @param stdClass $module
 985      * @return void
 986      * @throws coding_exception
 987      */
 988     public function set_cm($cm, $course = null, $module = null) {
 989         global $DB, $CFG, $SITE;
 990
 991         if (!isset($cm->id) || !isset($cm->course)) {
 992             throw new coding_exception('Invalid $cm. It has to be instance of cm_info or record from the course_modules table.');
 993         }
 994
 995         if (!$this->_course || $this->_course->id != $cm->course) {
 996             if (!$course) {
 997                 $course = $DB->get_record('course', array('id' => $cm->course), '*', MUST_EXIST);
 998             }
 999             if ($course->id != $cm->course) {
1000                 throw new coding_exception('The course you passed to $PAGE->set_cm does not correspond to the $cm.');
1001             }
1002             $this->set_course($course);
1003         }
1004
1005         // Make sure we have a $cm from get_fast_modinfo as this contains activity access details.
1006         if (!($cm instanceof cm_info)) {
1007             $modinfo = get_fast_modinfo($this->_course);
1008             $cm = $modinfo->get_cm($cm->id);
1009         }
1010         $this->_cm = $cm;
1011
1012         // Unfortunately the context setting is a mess.
1013         // Let's try to work around some common block problems and show some debug messages.
1014         if (empty($this->_context) or $this->_context->contextlevel != CONTEXT_BLOCK) {
1015             $context = context_module::instance($cm->id);
1016             $this->set_context($context);
1017         }
1018
1019         if ($module) {
1020             $this->set_activity_record($module);
1021         }
1022
1023         // Notify course format that this page is set for the course module.
1024         if ($this->_course->id != $SITE->id) {
1025             require_once($CFG->dirroot.'/course/lib.php');
1026             course_get_format($this->_course)->page_set_cm($this);
1027         }
1028     }
1029
1030     /**
1031      * Sets the activity record. This could be a row from the main table for a
1032      * module. For instance if the current module (cm) is a forum this should be a row
1033      * from the forum table.
1034      *
1035      * @param stdClass $module A row from the main database table for the module that this page belongs to.
1036      * @throws coding_exception
1037      */
1038     public function set_activity_record($module) {
1039         if (is_null($this->_cm)) {
1040             throw new coding_exception('You cannot call $PAGE->set_activity_record until after $PAGE->cm has been set.');
1041         }
1042         if ($module->id != $this->_cm->instance || $module->course != $this->_course->id) {
1043             throw new coding_exception('The activity record does not seem to correspond to the cm that has been set.');
1044         }
1045         $this->_module = $module;
1046     }
1047
1048     /**
1049      * Sets the pagetype to use for this page.
1050      *
1051      * Normally you do not need to set this manually, it is automatically created
1052      * from the script name. However, on some pages this is overridden.
1053      * For example the page type for course/view.php includes the course format,
1054      * for example 'course-view-weeks'. This gets used as the id attribute on
1055      * <body> and also for determining which blocks are displayed.
1056      *
1057      * @param string $pagetype e.g. 'my-index' or 'mod-quiz-attempt'.
1058      */
1059     public function set_pagetype($pagetype) {
1060         $this->_pagetype = $pagetype;
1061     }
1062
1063     /**
1064      * Sets the layout to use for this page.
1065      *
1066      * The page layout determines how the page will be displayed, things such as
1067      * block regions, content areas, etc are controlled by the layout.
1068      * The theme in use for the page will determine that the layout contains.
1069      *
1070      * This properly defaults to 'base', so you only need to call this function if
1071      * you want something different. The exact range of supported layouts is specified
1072      * in the standard theme.
1073      *
1074      * For an idea of the common page layouts see
1075      * {@link http://docs.moodle.org/dev/Themes_2.0#The_different_layouts_as_of_August_17th.2C_2010}
1076      * But please keep in mind that it may be (and normally is) out of date.
1077      * The only place to find an accurate up-to-date list of the page layouts
1078      * available for your version of Moodle is {@link theme/base/config.php}
1079      *
1080      * @param string $pagelayout the page layout this is. For example 'popup', 'home'.
1081      */
1082     public function set_pagelayout($pagelayout) {
1083         // Uncomment this to debug theme pagelayout issues like missing blocks.
1084         // if (!empty($this->_wherethemewasinitialised) && $pagelayout != $this->_pagelayout)
1085         //     debugging('Page layout has already been set and cannot be changed.', DEBUG_DEVELOPER);
1086         $this->_pagelayout = $pagelayout;
1087     }
1088
1089     /**
1090      * If context->id and pagetype are not enough to uniquely identify this page,
1091      * then you can set a subpage id as well. For example, the tags page sets
1092      *
1093      * @param string $subpage an arbitrary identifier that, along with context->id
1094      *      and pagetype, uniquely identifies this page.
1095      */
1096     public function set_subpage($subpage) {
1097         if (empty($subpage)) {
1098             $this->_subpage = '';
1099         } else {
1100             $this->_subpage = $subpage;
1101         }
1102     }
1103
1104     /**
1105      * Adds a CSS class to the body tag of the page.
1106      *
1107      * @param string $class add this class name ot the class attribute on the body tag.
1108      * @throws coding_exception
1109      */
1110     public function add_body_class($class) {
1111         if ($this->_state > self::STATE_BEFORE_HEADER) {
1112             throw new coding_exception('Cannot call moodle_page::add_body_class after output has been started.');
1113         }
1114         $this->_bodyclasses[$class] = 1;
1115     }
1116
1117     /**
1118      * Adds an array of body classes to the body tag of this page.
1119      *
1120      * @param array $classes this utility method calls add_body_class for each array element.
1121      */
1122     public function add_body_classes($classes) {
1123         foreach ($classes as $class) {
1124             $this->add_body_class($class);
1125         }
1126     }
1127
1128     /**
1129      * Sets the title for the page.
1130      * This is normally used within the title tag in the head of the page.
1131      *
1132      * @param string $title the title that should go in the <head> section of the HTML of this page.
1133      */
1134     public function set_title($title) {
1135         $title = format_string($title);
1136         $title = strip_tags($title);
1137         $title = str_replace('"', '&quot;', $title);
1138         $this->_title = $title;
1139     }
1140
1141     /**
1142      * Sets the heading to use for the page.
1143      * This is normally used as the main heading at the top of the content.
1144      *
1145      * @param string $heading the main heading that should be displayed at the top of the <body>.
1146      */
1147     public function set_heading($heading) {
1148         $this->_heading = format_string($heading);
1149     }
1150
1151     /**
1152      * Sets some HTML to use next to the heading {@link moodle_page::set_heading()}
1153      *
1154      * @param string $menu The menu/content to show in the heading
1155      */
1156     public function set_headingmenu($menu) {
1157         $this->_headingmenu = $menu;
1158     }
1159
1160     /**
1161      * Set the course category this page belongs to manually.
1162      *
1163      * This automatically sets $PAGE->course to be the site course. You cannot
1164      * use this method if you have already set $PAGE->course - in that case,
1165      * the category must be the one that the course belongs to. This also
1166      * automatically sets the page context to the category context.
1167      *
1168      * @param int $categoryid The id of the category to set.
1169      * @throws coding_exception
1170      */
1171     public function set_category_by_id($categoryid) {
1172         global $SITE;
1173         if (!is_null($this->_course)) {
1174             throw new coding_exception('Course has already been set. You cannot change the category now.');
1175         }
1176         if (is_array($this->_categories)) {
1177             throw new coding_exception('Course category has already been set. You cannot to change it now.');
1178         }
1179         $this->ensure_theme_not_set();
1180         $this->set_course($SITE);
1181         $this->load_category($categoryid);
1182         $this->set_context(context_coursecat::instance($categoryid));
1183     }
1184
1185     /**
1186      * Set a different path to use for the 'Moodle docs for this page' link.
1187      *
1188      * By default, it uses the pagetype, which is normally the same as the
1189      * script name. So, for example, for mod/quiz/attempt.php, pagetype is
1190      * mod-quiz-attempt, and so docspath is mod/quiz/attempt.
1191      *
1192      * @param string $path the path to use at the end of the moodle docs URL.
1193      */
1194     public function set_docs_path($path) {
1195         $this->_docspath = $path;
1196     }
1197
1198     /**
1199      * You should call this method from every page to set the URL that should be used to return to this page.
1200      *
1201      * Used, for example, by the blocks editing UI to know where to return the
1202      * user after an action.
1203      * For example, course/view.php does:
1204      *      $id = optional_param('id', 0, PARAM_INT);
1205      *      $PAGE->set_url('/course/view.php', array('id' => $id));
1206      *
1207      * @param moodle_url|string $url URL relative to $CFG->wwwroot or {@link moodle_url} instance
1208      * @param array $params parameters to add to the URL
1209      * @throws coding_exception
1210      */
1211     public function set_url($url, array $params = null) {
1212         global $CFG;
1213
1214         if (is_string($url) && strpos($url, 'http') !== 0) {
1215             if (strpos($url, '/') === 0) {
1216                 // We have to use httpswwwroot here, because of loginhttps pages.
1217                 $url = $CFG->httpswwwroot . $url;
1218             } else {
1219                 throw new coding_exception('Invalid parameter $url, has to be full url or in shortened form starting with /.');
1220             }
1221         }
1222
1223         $this->_url = new moodle_url($url, $params);
1224
1225         $fullurl = $this->_url->out_omit_querystring();
1226         if (strpos($fullurl, "$CFG->httpswwwroot/") !== 0) {
1227             debugging('Most probably incorrect set_page() url argument, it does not match the httpswwwroot!');
1228         }
1229         $shorturl = str_replace("$CFG->httpswwwroot/", '', $fullurl);
1230
1231         if (is_null($this->_pagetype)) {
1232             $this->initialise_default_pagetype($shorturl);
1233         }
1234     }
1235
1236     /**
1237      * Make sure page URL does not contain the given URL parameter.
1238      *
1239      * This should not be necessary if the script has called set_url properly.
1240      * However, in some situations like the block editing actions; when the URL
1241      * has been guessed, it will contain dangerous block-related actions.
1242      * Therefore, the blocks code calls this function to clean up such parameters
1243      * before doing any redirect.
1244      *
1245      * @param string $param the name of the parameter to make sure is not in the
1246      * page URL.
1247      */
1248     public function ensure_param_not_in_url($param) {
1249         $this->_url->remove_params($param);
1250     }
1251
1252     /**
1253      * Sets an alternative version of this page.
1254      *
1255      * There can be alternate versions of some pages (for example an RSS feed version).
1256      * Call this method for each alternative version available.
1257      * For each alternative version a link will be included in the <head> tag.
1258      *
1259      * @param string $title The title to give the alternate version.
1260      * @param string|moodle_url $url The URL of the alternate version.
1261      * @param string $mimetype The mime-type of the alternate version.
1262      * @throws coding_exception
1263      */
1264     public function add_alternate_version($title, $url, $mimetype) {
1265         if ($this->_state > self::STATE_BEFORE_HEADER) {
1266             throw new coding_exception('Cannot call moodle_page::add_alternate_version after output has been started.');
1267         }
1268         $alt = new stdClass;
1269         $alt->title = $title;
1270         $alt->url = $url;
1271         $this->_alternateversions[$mimetype] = $alt;
1272     }
1273
1274     /**
1275      * Specify a form control should be focused when the page has loaded.
1276      *
1277      * @param string $controlid the id of the HTML element to be focused.
1278      */
1279     public function set_focuscontrol($controlid) {
1280         $this->_focuscontrol = $controlid;
1281     }
1282
1283     /**
1284      * Specify a fragment of HTML that goes where the 'Turn editing on' button normally goes.
1285      *
1286      * @param string $html the HTML to display there.
1287      */
1288     public function set_button($html) {
1289         $this->_button = $html;
1290     }
1291
1292     /**
1293      * Set the capability that allows users to edit blocks on this page.
1294      *
1295      * Normally the default of 'moodle/site:manageblocks' is used, but a few
1296      * pages like the My Moodle page need to use a different capability
1297      * like 'moodle/my:manageblocks'.
1298      *
1299      * @param string $capability a capability.
1300      */
1301     public function set_blocks_editing_capability($capability) {
1302         $this->_blockseditingcap = $capability;
1303     }
1304
1305     /**
1306      * Some pages let you turn editing on for reasons other than editing blocks.
1307      * If that is the case, you can pass other capabilities that let the user
1308      * edit this page here.
1309      *
1310      * @param string|array $capability either a capability, or an array of capabilities.
1311      */
1312     public function set_other_editing_capability($capability) {
1313         if (is_array($capability)) {
1314             $this->_othereditingcaps = array_unique($this->_othereditingcaps + $capability);
1315         } else {
1316             $this->_othereditingcaps[] = $capability;
1317         }
1318     }
1319
1320     /**
1321      * Sets whether the browser should cache this page or not.
1322      *
1323      * @param bool $cacheable can this page be cached by the user's browser.
1324      */
1325     public function set_cacheable($cacheable) {
1326         $this->_cacheable = $cacheable;
1327     }
1328
1329     /**
1330      * Sets the page to periodically refresh
1331      *
1332      * This function must be called before $OUTPUT->header has been called or
1333      * a coding exception will be thrown.
1334      *
1335      * @param int $delay Sets the delay before refreshing the page, if set to null refresh is cancelled.
1336      * @throws coding_exception
1337      */
1338     public function set_periodic_refresh_delay($delay = null) {
1339         if ($this->_state > self::STATE_BEFORE_HEADER) {
1340             throw new coding_exception('You cannot set a periodic refresh delay after the header has been printed');
1341         }
1342         if ($delay === null) {
1343             $this->_periodicrefreshdelay = null;
1344         } else if (is_int($delay)) {
1345             $this->_periodicrefreshdelay = $delay;
1346         }
1347     }
1348
1349     /**
1350      * Force this page to use a particular theme.
1351      *
1352      * Please use this cautiously.
1353      * It is only intended to be used by the themes selector admin page.
1354      *
1355      * @param string $themename the name of the theme to use.
1356      */
1357     public function force_theme($themename) {
1358         $this->ensure_theme_not_set();
1359         $this->_theme = theme_config::load($themename);
1360     }
1361
1362     /**
1363      * Reload theme settings.
1364      *
1365      * This is used when we need to reset settings
1366      * because they are now double cached in theme.
1367      */
1368     public function reload_theme() {
1369         if (!is_null($this->_theme)) {
1370             $this->_theme = theme_config::load($this->_theme->name);
1371         }
1372     }
1373
1374     /**
1375      * This function indicates that current page requires the https when $CFG->loginhttps enabled.
1376      *
1377      * By using this function properly, we can ensure 100% https-ized pages
1378      * at our entire discretion (login, forgot_password, change_password)
1379      *
1380      * @return void
1381      * @throws coding_exception
1382      */
1383     public function https_required() {
1384         global $CFG;
1385
1386         if (!is_null($this->_url)) {
1387             throw new coding_exception('https_required() must be used before setting page url!');
1388         }
1389
1390         $this->ensure_theme_not_set();
1391
1392         $this->_https_login_required = true;
1393
1394         if (!empty($CFG->loginhttps)) {
1395             $CFG->httpswwwroot = str_replace('http:', 'https:', $CFG->wwwroot);
1396         } else {
1397             $CFG->httpswwwroot = $CFG->wwwroot;
1398         }
1399     }
1400
1401     /**
1402      * Makes sure that page previously marked with https_required() is really using https://, if not it redirects to https://
1403      *
1404      * @return void (may redirect to https://self)
1405      * @throws coding_exception
1406      */
1407     public function verify_https_required() {
1408         global $CFG, $FULLME;
1409
1410         if (is_null($this->_url)) {
1411             throw new coding_exception('verify_https_required() must be called after setting page url!');
1412         }
1413
1414         if (!$this->_https_login_required) {
1415             throw new coding_exception('verify_https_required() must be called only after https_required()!');
1416         }
1417
1418         if (empty($CFG->loginhttps)) {
1419             // Https not required, so stop checking.
1420             return;
1421         }
1422
1423         if (strpos($this->_url, 'https://')) {
1424             // Detect if incorrect PAGE->set_url() used, it is recommended to use root-relative paths there.
1425             throw new coding_exception('Invalid page url. It must start with https:// for pages that set https_required()!');
1426         }
1427
1428         if (!empty($CFG->sslproxy)) {
1429             // It does not make much sense to use sslproxy and loginhttps at the same time.
1430             return;
1431         }
1432
1433         // Now the real test and redirect!
1434         // NOTE: do NOT use this test for detection of https on current page because this code is not compatible with SSL proxies,
1435         //       instead use (strpos($CFG->httpswwwroot, 'https:') === 0).
1436         if (strpos($FULLME, 'https:') !== 0) {
1437             // This may lead to infinite redirect on an incorrectly configured site.
1438             // In that case set $CFG->loginhttps=0; within /config.php.
1439             redirect($this->_url);
1440         }
1441     }
1442
1443     // Initialisation methods =====================================================
1444     // These set various things up in a default way.
1445
1446     /**
1447      * This method is called when the page first moves out of the STATE_BEFORE_HEADER
1448      * state. This is our last change to initialise things.
1449      */
1450     protected function starting_output() {
1451         global $CFG;
1452
1453         if (!during_initial_install()) {
1454             $this->blocks->load_blocks();
1455             if (empty($this->_block_actions_done)) {
1456                 $this->_block_actions_done = true;
1457                 if ($this->blocks->process_url_actions($this)) {
1458                     redirect($this->url->out(false));
1459                 }
1460             }
1461             $this->blocks->create_all_block_instances();
1462         }
1463
1464         // If maintenance mode is on, change the page header.
1465         if (!empty($CFG->maintenance_enabled)) {
1466             $this->set_button('<a href="' . $CFG->wwwroot . '/' . $CFG->admin .
1467                     '/settings.php?section=maintenancemode">' . get_string('maintenancemode', 'admin') .
1468                     '</a> ' . $this->button);
1469
1470             $title = $this->title;
1471             if ($title) {
1472                 $title .= ' - ';
1473             }
1474             $this->set_title($title . get_string('maintenancemode', 'admin'));
1475         } else {
1476             // Show the messaging popup if there are messages.
1477             message_popup_window();
1478         }
1479
1480         $this->initialise_standard_body_classes();
1481     }
1482
1483     /**
1484      * Method for use by Moodle core to set up the theme. Do not
1485      * use this in your own code.
1486      *
1487      * Make sure the right theme for this page is loaded. Tell our
1488      * blocks_manager about the theme block regions, and then, if
1489      * we are $PAGE, set up the global $OUTPUT.
1490      *
1491      * @return void
1492      */
1493     public function initialise_theme_and_output() {
1494         global $OUTPUT, $PAGE, $SITE, $CFG;
1495
1496         if (!empty($this->_wherethemewasinitialised)) {
1497             return;
1498         }
1499
1500         if (!during_initial_install()) {
1501             // Detect PAGE->context mess.
1502             $this->magic_get_context();
1503         }
1504
1505         if (!$this->_course && !during_initial_install()) {
1506             $this->set_course($SITE);
1507         }
1508
1509         if (is_null($this->_theme)) {
1510             $themename = $this->resolve_theme();
1511             $this->_theme = theme_config::load($themename);
1512         }
1513
1514         $this->_theme->setup_blocks($this->pagelayout, $this->blocks);
1515         if ($this->_theme->enable_dock && !empty($CFG->allowblockstodock)) {
1516             $this->requires->strings_for_js(array('addtodock', 'undockitem', 'dockblock', 'undockblock', 'undockall', 'hidedockpanel', 'hidepanel'), 'block');
1517             $this->requires->string_for_js('thisdirectionvertical', 'langconfig');
1518             $this->requires->yui_module('moodle-core-dock-loader', 'M.core.dock.loader.initLoader');
1519         }
1520
1521         if ($this === $PAGE) {
1522             $target = null;
1523             if ($this->pagelayout === 'maintenance') {
1524                 // If the page is using the maintenance layout then we're going to force target to maintenance.
1525                 // This leads to a special core renderer that is designed to block access to API's that are likely unavailable for this
1526                 // page layout.
1527                 $target = RENDERER_TARGET_MAINTENANCE;
1528             }
1529             $OUTPUT = $this->get_renderer('core', null, $target);
1530         }
1531
1532         $this->_wherethemewasinitialised = debug_backtrace();
1533     }
1534
1535     /**
1536      * Work out the theme this page should use.
1537      *
1538      * This depends on numerous $CFG settings, and the properties of this page.
1539      *
1540      * @return string the name of the theme that should be used on this page.
1541      */
1542     protected function resolve_theme() {
1543         global $CFG, $USER, $SESSION;
1544
1545         if (empty($CFG->themeorder)) {
1546             $themeorder = array('course', 'category', 'session', 'user', 'site');
1547         } else {
1548             $themeorder = $CFG->themeorder;
1549             // Just in case, make sure we always use the site theme if nothing else matched.
1550             $themeorder[] = 'site';
1551         }
1552
1553         $mnetpeertheme = '';
1554         if (isloggedin() and isset($CFG->mnet_localhost_id) and $USER->mnethostid != $CFG->mnet_localhost_id) {
1555             require_once($CFG->dirroot.'/mnet/peer.php');
1556             $mnetpeer = new mnet_peer();
1557             $mnetpeer->set_id($USER->mnethostid);
1558             if ($mnetpeer->force_theme == 1 && $mnetpeer->theme != '') {
1559                 $mnetpeertheme = $mnetpeer->theme;
1560             }
1561         }
1562
1563         foreach ($themeorder as $themetype) {
1564             switch ($themetype) {
1565                 case 'course':
1566                     if (!empty($CFG->allowcoursethemes) && !empty($this->_course->theme) && $this->devicetypeinuse == 'default') {
1567                         return $this->_course->theme;
1568                     }
1569                 break;
1570
1571                 case 'category':
1572                     if (!empty($CFG->allowcategorythemes) && $this->devicetypeinuse == 'default') {
1573                         $categories = $this->categories;
1574                         foreach ($categories as $category) {
1575                             if (!empty($category->theme)) {
1576                                 return $category->theme;
1577                             }
1578                         }
1579                     }
1580                 break;
1581
1582                 case 'session':
1583                     if (!empty($SESSION->theme)) {
1584                         return $SESSION->theme;
1585                     }
1586                 break;
1587
1588                 case 'user':
1589                     if (!empty($CFG->allowuserthemes) && !empty($USER->theme) && $this->devicetypeinuse == 'default') {
1590                         if ($mnetpeertheme) {
1591                             return $mnetpeertheme;
1592                         } else {
1593                             return $USER->theme;
1594                         }
1595                     }
1596                 break;
1597
1598                 case 'site':
1599                     if ($mnetpeertheme) {
1600                         return $mnetpeertheme;
1601                     }
1602                     // First try for the device the user is using.
1603                     $devicetheme = core_useragent::get_device_type_theme($this->devicetypeinuse);
1604                     if (!empty($devicetheme)) {
1605                         return $devicetheme;
1606                     }
1607                     // Next try for the default device (as a fallback).
1608                     $devicetheme = core_useragent::get_device_type_theme('default');
1609                     if (!empty($devicetheme)) {
1610                         return $devicetheme;
1611                     }
1612                     // The default device theme isn't set up - use the overall default theme.
1613                     return theme_config::DEFAULT_THEME;
1614             }
1615         }
1616
1617         // We should most certainly have resolved a theme by now. Something has gone wrong.
1618         debugging('Error resolving the theme to use for this page.', DEBUG_DEVELOPER);
1619         return theme_config::DEFAULT_THEME;
1620     }
1621
1622
1623     /**
1624      * Sets ->pagetype from the script name. For example, if the script that was
1625      * run is mod/quiz/view.php, ->pagetype will be set to 'mod-quiz-view'.
1626      *
1627      * @param string $script the path to the script that should be used to
1628      * initialise ->pagetype. If not passed the $SCRIPT global will be used.
1629      * If legacy code has set $CFG->pagepath that will be used instead, and a
1630      * developer warning issued.
1631      */
1632     protected function initialise_default_pagetype($script = null) {
1633         global $CFG, $SCRIPT;
1634
1635         if (isset($CFG->pagepath)) {
1636             debugging('Some code appears to have set $CFG->pagepath. That was a horrible deprecated thing. ' .
1637                     'Don\'t do it! Try calling $PAGE->set_pagetype() instead.');
1638             $script = $CFG->pagepath;
1639             unset($CFG->pagepath);
1640         }
1641
1642         if (is_null($script)) {
1643             $script = ltrim($SCRIPT, '/');
1644             $len = strlen($CFG->admin);
1645             if (substr($script, 0, $len) == $CFG->admin) {
1646                 $script = 'admin' . substr($script, $len);
1647             }
1648         }
1649
1650         $path = str_replace('.php', '', $script);
1651         if (substr($path, -1) == '/') {
1652             $path .= 'index';
1653         }
1654
1655         if (empty($path) || $path == 'index') {
1656             $this->_pagetype = 'site-index';
1657         } else {
1658             $this->_pagetype = str_replace('/', '-', $path);
1659         }
1660     }
1661
1662     /**
1663      * Initialises the CSS classes that will be added to body tag of the page.
1664      *
1665      * The function is responsible for adding all of the critical CSS classes
1666      * that describe the current page, and its state.
1667      * This includes classes that describe the following for example:
1668      *    - Current language
1669      *    - Language direction
1670      *    - YUI CSS initialisation
1671      *    - Pagelayout
1672      * These are commonly used in CSS to target specific types of pages.
1673      */
1674     protected function initialise_standard_body_classes() {
1675         global $CFG, $USER;
1676
1677         $pagetype = $this->pagetype;
1678         if ($pagetype == 'site-index') {
1679             $this->_legacyclass = 'course';
1680         } else if (substr($pagetype, 0, 6) == 'admin-') {
1681             $this->_legacyclass = 'admin';
1682         }
1683         $this->add_body_class($this->_legacyclass);
1684
1685         $pathbits = explode('-', trim($pagetype));
1686         for ($i = 1; $i < count($pathbits); $i++) {
1687             $this->add_body_class('path-' . join('-', array_slice($pathbits, 0, $i)));
1688         }
1689
1690         $this->add_body_classes(core_useragent::get_browser_version_classes());
1691         $this->add_body_class('dir-' . get_string('thisdirection', 'langconfig'));
1692         $this->add_body_class('lang-' . current_language());
1693         $this->add_body_class('yui-skin-sam'); // Make YUI happy, if it is used.
1694         $this->add_body_class('yui3-skin-sam'); // Make YUI3 happy, if it is used.
1695         $this->add_body_class($this->url_to_class_name($CFG->wwwroot));
1696
1697         // Extra class describing current page layout.
1698         $this->add_body_class('pagelayout-' . $this->_pagelayout);
1699
1700         if (!during_initial_install()) {
1701             $this->add_body_class('course-' . $this->_course->id);
1702             $this->add_body_class('context-' . $this->_context->id);
1703         }
1704
1705         if (!empty($this->_cm)) {
1706             $this->add_body_class('cmid-' . $this->_cm->id);
1707         }
1708
1709         if (!empty($CFG->allowcategorythemes)) {
1710             $this->ensure_category_loaded();
1711             foreach ($this->_categories as $catid => $notused) {
1712                 $this->add_body_class('category-' . $catid);
1713             }
1714         } else {
1715             $catid = 0;
1716             if (is_array($this->_categories)) {
1717                 $catids = array_keys($this->_categories);
1718                 $catid = reset($catids);
1719             } else if (!empty($this->_course->category)) {
1720                 $catid = $this->_course->category;
1721             }
1722             if ($catid) {
1723                 $this->add_body_class('category-' . $catid);
1724             }
1725         }
1726
1727         if (!isloggedin()) {
1728             $this->add_body_class('notloggedin');
1729         }
1730
1731         if (!empty($USER->editing)) {
1732             $this->add_body_class('editing');
1733             if (optional_param('bui_moveid', false, PARAM_INT)) {
1734                 $this->add_body_class('blocks-moving');
1735             }
1736         }
1737
1738         if (!empty($CFG->blocksdrag)) {
1739             $this->add_body_class('drag');
1740         }
1741
1742         if ($this->_devicetypeinuse != 'default') {
1743             $this->add_body_class($this->_devicetypeinuse . 'theme');
1744         }
1745     }
1746
1747     /**
1748      * Loads the activity record for the current CM object associated with this
1749      * page.
1750      *
1751      * This will load {@link moodle_page::$_module} with a row from the related
1752      * module table in the database.
1753      * For instance if {@link moodle_page::$_cm} is a forum then a row from the
1754      * forum table will be loaded.
1755      */
1756     protected function load_activity_record() {
1757         global $DB;
1758         if (is_null($this->_cm)) {
1759             return;
1760         }
1761         $this->_module = $DB->get_record($this->_cm->modname, array('id' => $this->_cm->instance));
1762     }
1763
1764     /**
1765      * This function ensures that the category of the current course has been
1766      * loaded, and if not, the function loads it now.
1767      *
1768      * @return void
1769      * @throws coding_exception
1770      */
1771     protected function ensure_category_loaded() {
1772         if (is_array($this->_categories)) {
1773             return; // Already done.
1774         }
1775         if (is_null($this->_course)) {
1776             throw new coding_exception('Attempt to get the course category for this page before the course was set.');
1777         }
1778         if ($this->_course->category == 0) {
1779             $this->_categories = array();
1780         } else {
1781             $this->load_category($this->_course->category);
1782         }
1783     }
1784
1785     /**
1786      * Loads the requested category into the pages categories array.
1787      *
1788      * @param int $categoryid
1789      * @throws moodle_exception
1790      */
1791     protected function load_category($categoryid) {
1792         global $DB;
1793         $category = $DB->get_record('course_categories', array('id' => $categoryid));
1794         if (!$category) {
1795             throw new moodle_exception('unknowncategory');
1796         }
1797         $this->_categories[$category->id] = $category;
1798         $parentcategoryids = explode('/', trim($category->path, '/'));
1799         array_pop($parentcategoryids);
1800         foreach (array_reverse($parentcategoryids) as $catid) {
1801             $this->_categories[$catid] = null;
1802         }
1803     }
1804
1805     /**
1806      * Ensures that the category the current course is within, as well as all of
1807      * its parent categories, have been loaded.
1808      *
1809      * @return void
1810      */
1811     protected function ensure_categories_loaded() {
1812         global $DB;
1813         $this->ensure_category_loaded();
1814         if (!is_null(end($this->_categories))) {
1815             return; // Already done.
1816         }
1817         $idstoload = array_keys($this->_categories);
1818         array_shift($idstoload);
1819         $categories = $DB->get_records_list('course_categories', 'id', $idstoload);
1820         foreach ($idstoload as $catid) {
1821             $this->_categories[$catid] = $categories[$catid];
1822         }
1823     }
1824
1825     /**
1826      * Ensure the theme has not been loaded yet. If it has an exception is thrown.
1827      *
1828      * @throws coding_exception
1829      */
1830     protected function ensure_theme_not_set() {
1831         if (!is_null($this->_theme)) {
1832             throw new coding_exception('The theme has already been set up for this page ready for output. ' .
1833                     'Therefore, you can no longer change the theme, or anything that might affect what ' .
1834                     'the current theme is, for example, the course.',
1835                     'Stack trace when the theme was set up: ' . format_backtrace($this->_wherethemewasinitialised));
1836         }
1837     }
1838
1839     /**
1840      * Converts the provided URL into a CSS class that be used within the page.
1841      * This is primarily used to add the wwwroot to the body tag as a CSS class.
1842      *
1843      * @param string $url
1844      * @return string
1845      */
1846     protected function url_to_class_name($url) {
1847         $bits = parse_url($url);
1848         $class = str_replace('.', '-', $bits['host']);
1849         if (!empty($bits['port'])) {
1850             $class .= '--' . $bits['port'];
1851         }
1852         if (!empty($bits['path'])) {
1853             $path = trim($bits['path'], '/');
1854             if ($path) {
1855                 $class .= '--' . str_replace('/', '-', $path);
1856             }
1857         }
1858         return $class;
1859     }
1860
1861     /**
1862      * Combines all of the required editing caps for the page and returns them
1863      * as an array.
1864      *
1865      * @return array
1866      */
1867     protected function all_editing_caps() {
1868         $caps = $this->_othereditingcaps;
1869         $caps[] = $this->_blockseditingcap;
1870         return $caps;
1871     }
1872
1873     /**
1874      * Returns true if the page URL has beem set.
1875      *
1876      * @return bool
1877      */
1878     public function has_set_url() {
1879         return ($this->_url!==null);
1880     }
1881
1882     /**
1883      * Gets set when the block actions for the page have been processed.
1884      *
1885      * @param bool $setting
1886      */
1887     public function set_block_actions_done($setting = true) {
1888         $this->_block_actions_done = $setting;
1889     }
1890
1891     /**
1892      * Are popup notifications allowed on this page?
1893      * Popup notifications may be disallowed in situations such as while upgrading or completing a quiz
1894      *
1895      * @return bool true if popup notifications may be displayed
1896      */
1897     public function get_popup_notification_allowed() {
1898         return $this->_popup_notification_allowed;
1899     }
1900
1901     /**
1902      * Allow or disallow popup notifications on this page. Popups are allowed by default.
1903      *
1904      * @param bool $allowed true if notifications are allowed. False if not allowed. They are allowed by default.
1905      */
1906     public function set_popup_notification_allowed($allowed) {
1907         $this->_popup_notification_allowed = $allowed;
1908     }
1909
1910     /**
1911      * Returns the block region having made any required theme manipulations.
1912      *
1913      * @since Moodle 2.5.1 2.6
1914      * @param string $region
1915      * @return string
1916      */
1917     public function apply_theme_region_manipulations($region) {
1918         if ($this->blockmanipulations && isset($this->blockmanipulations[$region])) {
1919             $regionwas = $region;
1920             $regionnow = $this->blockmanipulations[$region];
1921             if ($this->blocks->is_known_region($regionwas) && $this->blocks->is_known_region($regionnow)) {
1922                 // Both the before and after regions are known so we can swap them over.
1923                 return $regionnow;
1924             }
1925             // We didn't know about both, we won't swap them over.
1926             return $regionwas;
1927         }
1928         return $region;
1929     }
1930 }