lib/outputrequirementslib.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle is free software: you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation, either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18
  19 /**
  20  * Library functions to facilitate the use of JavaScript in Moodle.
  21  *
  22  * @package    core
  23  * @subpackage lib
  24  * @copyright  2009 Tim Hunt, 2010 Petr Skoda
  25  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  26  */
  27
  28 defined('MOODLE_INTERNAL') || die();
  29
  30 // note: you can find history of this file in lib/ajax/ajaxlib.php
  31
  32 /**
  33  * This class tracks all the things that are needed by the current page.
  34  *
  35  * Normally, the only instance of this  class you will need to work with is the
  36  * one accessible via $PAGE->requires.
  37  *
  38  * Typical usage would be
  39  * <pre>
  40  *     $PAGE->requires->js_init_call('M.mod_forum.init_view');
  41  * </pre>
  42  *
  43  * It also supports obsoleted coding style withouth YUI3 modules.
  44  * <pre>
  45  *     $PAGE->requires->css('/mod/mymod/userstyles.php?id='.$id); // not overridable via themes!
  46  *     $PAGE->requires->js('/mod/mymod/script.js');
  47  *     $PAGE->requires->js('/mod/mymod/small_but_urgent.js', true);
  48  *     $PAGE->requires->js_function_call('init_mymod', array($data), true);
  49  * </pre>
  50  *
  51  * There are some natural restrictions on some methods. For example, {@link css()}
  52  * can only be called before the <head> tag is output. See the comments on the
  53  * individual methods for details.
  54  *
  55  * @copyright 2009 Tim Hunt, 2010 Petr Skoda
  56  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  57  * @since Moodle 2.0
  58  */
  59 class page_requirements_manager {
  60     /** List of string available from JS */
  61     protected $stringsforjs = array();
  62     /** List of JS variables to be initialised */
  63     protected $jsinitvariables = array('head'=>array(), 'footer'=>array());
  64     /** Included JS scripts */
  65     protected $jsincludes = array('head'=>array(), 'footer'=>array());
  66     /** List of needed function calls */
  67     protected $jscalls = array('normal'=>array(), 'ondomready'=>array());
  68     /**
  69      * List of skip links, those are needed for accessibility reasons
  70      * @var array
  71      */
  72     protected $skiplinks = array();
  73     /**
  74      * Javascript code used for initialisation of page, it should be relatively small
  75      * @var array
  76      */
  77     protected $jsinitcode = array();
  78     /**
  79      * Theme sheets, initialised only from core_renderer
  80      * @var array of moodle_url
  81      */
  82     protected $cssthemeurls = array();
  83     /**
  84      * List of custom theme sheets, these are strongly discouraged!
  85      * Useful mostly only for CSS submitted by teachers that is not part of the theme.
  86      * @var array of moodle_url
  87      */
  88     protected $cssurls = array();
  89     /**
  90      * List of requested event handlers
  91      * @var array
  92      */
  93     protected $eventhandlers = array();
  94     /**
  95      * Extra modules
  96      * @var array
  97      */
  98     protected $extramodules = array();
  99     /** Flag indicated head stuff already printed */
 100     protected $headdone = false;
 101     /** Flag indicating top of body already printed */
 102     protected $topofbodydone = false;
 103
 104     /** YUI PHPLoader instance responsible for YUI2 loading from PHP only */
 105     protected $yui2loader;
 106     /** YUI PHPLoader instance responsible for YUI3 loading from PHP only */
 107     protected $yui3loader;
 108     /** YUI PHPLoader instance responsible for YUI3 loading from javascript */
 109     protected $M_yui_loader;
 110     /** some config vars exposed in JS, please no secret stuff there */
 111     protected $M_cfg;
 112     /** stores debug backtraces from when JS modules were included in the page */
 113     protected $debug_moduleloadstacktraces = array();
 114
 115     /**
 116      * Page requirements constructor.
 117      */
 118     public function __construct() {
 119         global $CFG;
 120
 121         require_once("$CFG->libdir/yui/phploader/phploader/loader.php");
 122
 123         $this->yui3loader = new YAHOO_util_Loader($CFG->yui3version);
 124         $this->yui2loader = new YAHOO_util_Loader($CFG->yui2version);
 125
 126         // set up some loader options
 127         if (debugging('', DEBUG_DEVELOPER)) {
 128             $this->yui3loader->filter = YUI_DEBUG; // alternatively we could use just YUI_RAW here
 129             $this->yui2loader->filter = YUI_DEBUG; // alternatively we could use just YUI_RAW here
 130         } else {
 131             $this->yui3loader->filter = null;
 132             $this->yui2loader->filter = null;
 133         }
 134         if (!empty($CFG->useexternalyui)) {
 135             $this->yui3loader->base = 'http://yui.yahooapis.com/' . $CFG->yui3version . '/build/';
 136             $this->yui2loader->base = 'http://yui.yahooapis.com/' . $CFG->yui2version . '/build/';
 137             $this->yui3loader->comboBase = 'http://yui.yahooapis.com/combo?';
 138             $this->yui2loader->comboBase = 'http://yui.yahooapis.com/combo?';
 139         } else {
 140             $this->yui3loader->base = $CFG->httpswwwroot . '/lib/yui/'. $CFG->yui3version . '/build/';
 141             $this->yui2loader->base = $CFG->httpswwwroot . '/lib/yui/'. $CFG->yui2version . '/build/';
 142             $this->yui3loader->comboBase = $CFG->httpswwwroot . '/theme/yui_combo.php?';
 143             $this->yui2loader->comboBase = $CFG->httpswwwroot . '/theme/yui_combo.php?';
 144         }
 145
 146         // enable combo loader? this significantly helps with caching and performance!
 147         $this->yui3loader->combine = !empty($CFG->yuicomboloading);
 148         $this->yui2loader->combine = !empty($CFG->yuicomboloading);
 149
 150         if (empty($CFG->cachejs)) {
 151             $jsrev = -1;
 152         } else if (empty($CFG->jsrev)) {
 153             $jsrev = 1;
 154         } else {
 155             $jsrev = $CFG->jsrev;
 156         }
 157
 158         // set up JS YUI loader helper object
 159         $this->M_yui_loader = new stdClass();
 160         $this->M_yui_loader->base         = $this->yui3loader->base;
 161         $this->M_yui_loader->comboBase    = $this->yui3loader->comboBase;
 162         $this->M_yui_loader->combine      = $this->yui3loader->combine;
 163         $this->M_yui_loader->filter       = ($this->yui3loader->filter == YUI_DEBUG) ? 'debug' : '';
 164         $this->M_yui_loader->insertBefore = 'firstthemesheet';
 165         $this->M_yui_loader->modules      = array();
 166         $this->M_yui_loader->groups       = array(
 167             'moodle' => array(
 168                 'name' => 'moodle',
 169                 'base' => $CFG->httpswwwroot . '/theme/yui_combo.php?moodle/'.$jsrev.'/',
 170                 'comboBase' => $CFG->httpswwwroot . '/theme/yui_combo.php?',
 171                 'combine' => $this->yui3loader->combine,
 172                 'filter' => '',
 173                 'ext' => false,
 174                 'root' => 'moodle/'.$jsrev.'/', // Add the rev to the root path so that we can control caching
 175                 'patterns' => array(
 176                     'moodle-' => array(
 177                         'group' => 'moodle',
 178                         'configFn' => '@MOODLECONFIGFN@'
 179                     ),
 180                     'root' => 'moodle'
 181                 )
 182             ),
 183             'local' => array(
 184                 'name' => 'gallery',
 185                 'base' => $CFG->wwwroot.'/lib/yui/gallery/',
 186                 'comboBase' => $CFG->httpswwwroot . '/theme/yui_combo.php?',
 187                 'combine' => $this->yui3loader->combine,
 188                 'filter' => $this->M_yui_loader->filter,
 189                 'ext' => false,
 190                 'root' => 'gallery/',
 191                 'patterns' => array(
 192                     'gallery-' => array(
 193                         'group' => 'gallery',
 194                         'configFn' => '@GALLERYCONFIGFN@',
 195                     ),
 196                     'root' => 'gallery'
 197                 )
 198             )
 199         );
 200         $this->add_yui2_modules(); // adds loading info for all YUI2 modules
 201         $this->js_module($this->find_module('core_filepicker'));
 202         $this->js_module($this->find_module('core_dock'));
 203
 204         // YUI3 init code
 205         $libs = array('cssreset', 'cssbase', 'cssfonts', 'cssgrids', 'node', 'loader'); // full CSS reset + basic libs
 206         foreach ($libs as $lib) {
 207             $this->yui3loader->load($lib);
 208         }
 209     }
 210
 211     /**
 212      * This method adds yui2 modules into the yui3 JS loader-
 213      * @return void
 214      */
 215     protected function add_yui2_modules() {
 216         //note: this function is definitely not perfect, because
 217         //      it adds tons of markup into each page, but it can be
 218         //      abstracted into separate JS file with proper headers
 219         global $CFG;
 220
 221         $GLOBALS['yui_current'] = array();
 222         require($CFG->libdir.'/yui/phploader/lib/meta/config_'.$CFG->yui2version.'.php');
 223         $info = $GLOBALS['yui_current'];
 224         unset($GLOBALS['yui_current']);
 225
 226         if (empty($CFG->yuicomboloading)) {
 227             $urlbase = $this->yui2loader->base;
 228         } else {
 229             $urlbase = $this->yui2loader->comboBase.$CFG->yui2version.'/build/';
 230         }
 231
 232         $modules = array();
 233         $ignored = array(); // list of CSS modules that are not needed
 234         foreach ($info['moduleInfo'] as $name => $module) {
 235             if ($module['type'] === 'css') {
 236                 $ignored[$name] = true;
 237             } else {
 238                 $modules['yui2-'.$name] = $module;
 239             }
 240         }
 241         foreach ($modules as $name=>$module) {
 242             $module['fullpath'] = $urlbase.$module['path']; // fix path to point to correct location
 243             unset($module['path']);
 244             unset($module['skinnable']); // we load all YUI2 css automatically, this prevents weird missing css loader problems
 245             foreach(array('requires', 'optional', 'supersedes') as $fixme) {
 246                 if (!empty($module[$fixme])) {
 247                     $fixed = false;
 248                     foreach ($module[$fixme] as $key=>$dep) {
 249                         if (isset($ignored[$dep])) {
 250                             unset($module[$fixme][$key]);
 251                             $fixed = true;
 252                         } else {
 253                             $module[$fixme][$key] = 'yui2-'.$dep;
 254                         }
 255                     }
 256                     if ($fixed) {
 257                         $module[$fixme] = array_merge($module[$fixme]); // fix keys
 258                     }
 259                 }
 260             }
 261             $this->M_yui_loader->modules[$name] = $module;
 262             if (debugging('', DEBUG_DEVELOPER)) {
 263                 if (!array_key_exists($name, $this->debug_moduleloadstacktraces)) {
 264                     $this->debug_moduleloadstacktraces[$name] = array();
 265                 }
 266                 $this->debug_moduleloadstacktraces[$name][] = format_backtrace(debug_backtrace());
 267             }
 268         }
 269     }
 270
 271     /**
 272      * Initialise with the bits of JavaScript that every Moodle page should have.
 273      *
 274      * @param moodle_page $page
 275      * @param core_renderer $output
 276      */
 277     protected function init_requirements_data(moodle_page $page, core_renderer $renderer) {
 278         global $CFG;
 279
 280         // JavaScript should always work with $CFG->httpswwwroot rather than $CFG->wwwroot.
 281         // Otherwise, in some situations, users will get warnings about insecure content
 282         // on secure pages from their web browser.
 283
 284         $this->M_cfg = array(
 285             'wwwroot'             => $CFG->httpswwwroot, // Yes, really. See above.
 286             'sesskey'             => sesskey(),
 287             'loadingicon'         => $renderer->pix_url('i/loading_small', 'moodle')->out(false),
 288             'themerev'            => theme_get_revision(),
 289             'theme'               => $page->theme->name,
 290             'jsrev'               => ((empty($CFG->cachejs) or empty($CFG->jsrev)) ? -1 : $CFG->jsrev),
 291         );
 292         if (debugging('', DEBUG_DEVELOPER)) {
 293             $this->M_cfg['developerdebug'] = true;
 294             $this->yui2_lib('logger');
 295         }
 296
 297         // accessibility stuff
 298         $this->skip_link_to('maincontent', get_string('tocontent', 'access'));
 299
 300         // to be removed soon
 301         $this->yui2_lib('dom');        // at least javascript-static.js needs to be migrated to YUI3
 302
 303         $this->string_for_js('confirmation', 'admin');
 304         $this->string_for_js('cancel', 'moodle');
 305         $this->string_for_js('yes', 'moodle');
 306
 307         if ($page->pagelayout === 'frametop') {
 308             $this->js_init_call('M.util.init_frametop');
 309         }
 310     }
 311
 312     /**
 313      * Ensure that the specified JavaScript file is linked to from this page.
 314      *
 315      * NOTE: This function is to be used in rare cases only, please store your JS in module.js file
 316      * and use $PAGE->requires->js_init_call() instead.
 317      *
 318      * By default the link is put at the end of the page, since this gives best page-load performance.
 319      *
 320      * Even if a particular script is requested more than once, it will only be linked
 321      * to once.
 322      *
 323      * @param string|moodle_url $url The path to the .js file, relative to $CFG->dirroot / $CFG->wwwroot.
 324      *      For example '/mod/mymod/customscripts.js'; use moodle_url for external scripts
 325      * @param bool $inhead initialise in head
 326      * @return void
 327      */
 328     public function js($url, $inhead=false) {
 329         $url = $this->js_fix_url($url);
 330         $where = $inhead ? 'head' : 'footer';
 331         $this->jsincludes[$where][$url->out()] = $url;
 332     }
 333
 334     /**
 335      * Ensure that the specified YUI2 library file, and all its required dependencies,
 336      * are linked to from this page.
 337      *
 338      * By default the link is put at the end of the page, since this gives best page-load
 339      * performance. Optional dependencies are not loaded automatically - if you want
 340      * them you will need to load them first with other calls to this method.
 341      *
 342      * Even if a particular library is requested more than once (perhaps as a dependency
 343      * of other libraries) it will only be linked to once.
 344      *
 345      * The library is leaded as soon as possible, if $OUTPUT->header() not used yet it
 346      * is put into the page header, otherwise it is loaded in the page footer.
 347      *
 348      * @param string|array $libname the name of the YUI2 library you require. For example 'autocomplete'.
 349      * @return void
 350      */
 351     public function yui2_lib($libname) {
 352         $libnames = (array)$libname;
 353         foreach ($libnames as $lib) {
 354             $this->yui2loader->load($lib);
 355         }
 356     }
 357
 358     /**
 359      * Returns the actual url through which a script is served.
 360      * @param moodle_url|string $url full moodle url, or shortened path to script
 361      * @return moodle_url
 362      */
 363     protected function js_fix_url($url) {
 364         global $CFG;
 365
 366         if ($url instanceof moodle_url) {
 367             return $url;
 368         } else if (strpos($url, '/') === 0) {
 369             if (debugging()) {
 370                 // check file existence only when in debug mode
 371                 if (!file_exists($CFG->dirroot . strtok($url, '?'))) {
 372                     throw new coding_exception('Attempt to require a JavaScript file that does not exist.', $url);
 373                 }
 374             }
 375             if (!empty($CFG->cachejs) and !empty($CFG->jsrev) and strpos($url, '/lib/editor/') !== 0 and substr($url, -3) === '.js') {
 376                 return new moodle_url($CFG->httpswwwroot.'/lib/javascript.php', array('file'=>$url, 'rev'=>$CFG->jsrev));
 377             } else {
 378                 return new moodle_url($CFG->httpswwwroot.$url);
 379             }
 380         } else {
 381             throw new coding_exception('Invalid JS url, it has to be shortened url starting with / or moodle_url instance.', $url);
 382         }
 383     }
 384
 385     /**
 386      * Find out if JS module present and return details.
 387      * @param string $component name of component in frankenstyle, ex: core_group, mod_forum
 388      * @return array description of module or null if not found
 389      */
 390     protected function find_module($component) {
 391         global $CFG;
 392
 393         $module = null;
 394
 395
 396         if (strpos($component, 'core_') === 0) {
 397             // must be some core stuff - list here is not complete, this is just the stuff used from multiple places
 398             // so that we do nto have to repeat the definition of these modules over and over again
 399             switch($component) {
 400                 case 'core_filepicker':
 401                     $module = array('name'     => 'core_filepicker',
 402                                     'fullpath' => '/repository/filepicker.js',
 403                                     'requires' => array('base', 'node', 'node-event-simulate', 'json', 'async-queue', 'io', 'yui2-button', 'yui2-container', 'yui2-layout', 'yui2-menu', 'yui2-treeview', 'yui2-dragdrop', 'yui2-cookie'),
 404                                     'strings'  => array(array('add', 'repository'), array('back', 'repository'), array('cancel', 'moodle'), array('close', 'repository'),
 405                                                         array('cleancache', 'repository'), array('copying', 'repository'), array('date', 'repository'), array('downloadsucc', 'repository'),
 406                                                         array('emptylist', 'repository'), array('error', 'repository'), array('federatedsearch', 'repository'),
 407                                                         array('filenotnull', 'repository'), array('getfile', 'repository'), array('help', 'moodle'), array('iconview', 'repository'),
 408                                                         array('invalidjson', 'repository'), array('linkexternal', 'repository'), array('listview', 'repository'),
 409                                                         array('loading', 'repository'), array('login', 'repository'), array('logout', 'repository'), array('noenter', 'repository'),
 410                                                         array('noresult', 'repository'), array('manageurl', 'repository'), array('popup', 'repository'), array('preview', 'repository'),
 411                                                         array('refresh', 'repository'), array('save', 'repository'), array('saveas', 'repository'), array('saved', 'repository'),
 412                                                         array('saving', 'repository'), array('search', 'repository'), array('searching', 'repository'), array('size', 'repository'),
 413                                                         array('submit', 'repository'), array('sync', 'repository'), array('title', 'repository'), array('upload', 'repository'),
 414                                                         array('uploading', 'repository'), array('xhtmlerror', 'repository'),
 415                                                         array('cancel'), array('chooselicense', 'repository'), array('author', 'repository'),
 416                                                         array('ok', 'moodle'), array('error', 'moodle'), array('info', 'moodle'), array('norepositoriesavailable', 'repository'), array('norepositoriesexternalavailable', 'repository'),
 417                                                         array('nofilesattached', 'repository'), array('filepicker', 'repository'),
 418                                                         array('nofilesavailable', 'repository'), array('overwrite', 'repository'),
 419                                                         array('renameto', 'repository'), array('fileexists', 'repository'),
 420                                                         array('fileexistsdialogheader', 'repository'), array('fileexistsdialog_editor', 'repository'),
 421                                                         array('fileexistsdialog_filemanager', 'repository')
 422                                                     ));
 423                     break;
 424                 case 'core_comment':
 425                     $module = array('name'     => 'core_comment',
 426                                     'fullpath' => '/comment/comment.js',
 427                                     'requires' => array('base', 'io', 'node', 'json', 'yui2-animation', 'overlay'),
 428                                     'strings' => array(array('confirmdeletecomments', 'admin'), array('yes', 'moodle'), array('no', 'moodle'))
 429                                 );
 430                     break;
 431                 case 'core_role':
 432                     $module = array('name'     => 'core_role',
 433                                     'fullpath' => '/admin/roles/module.js',
 434                                     'requires' => array('node', 'cookie'));
 435                     break;
 436                 case 'core_completion':
 437                     $module = array('name'     => 'core_completion',
 438                                     'fullpath' => '/course/completion.js');
 439                     break;
 440                 case 'core_dock':
 441                     $module = array('name'     => 'core_dock',
 442                                     'fullpath' => '/blocks/dock.js',
 443                                     'requires' => array('base', 'node', 'event-custom', 'event-mouseenter', 'event-resize'),
 444                                     'strings' => array(array('addtodock', 'block'),array('undockitem', 'block'),array('undockall', 'block'),array('thisdirectionvertical', 'langconfig')));
 445                     break;
 446                 case 'core_message':
 447                     $module = array('name'     => 'core_message',
 448                                     'fullpath' => '/message/module.js');
 449                     break;
 450                 case 'core_flashdetect':
 451                     $module = array('name'     => 'core_flashdetect',
 452                                     'fullpath' => '/lib/flashdetect/flashdetect.js',
 453                                     'requires' => array('io'));
 454                     break;
 455                 case 'core_group':
 456                     $module = array('name'     => 'core_group',
 457                                     'fullpath' => '/group/module.js',
 458                                     'requires' => array('node', 'overlay', 'event-mouseenter'));
 459                     break;
 460                 case 'core_question_engine':
 461                     $module = array('name'     => 'core_question_engine',
 462                                     'fullpath' => '/question/qengine.js',
 463                                     'requires' => array('node', 'event'));
 464                     break;
 465                 case 'core_rating':
 466                     $module = array('name'     => 'core_rating',
 467                                     'fullpath' => '/rating/module.js',
 468                                     'requires' => array('node', 'event', 'overlay', 'io', 'json'));
 469                     break;
 470                 case 'core_filetree':
 471                     $module = array('name'     => 'core_filetree',
 472                                     'fullpath' => '/files/module.js',
 473                                     'requires' => array('node', 'event', 'overlay', 'io', 'json', 'yui2-treeview'));
 474                     break;
 475             }
 476
 477         } else {
 478             if ($dir = get_component_directory($component)) {
 479                 if (file_exists("$dir/module.js")) {
 480                     if (strpos($dir, $CFG->dirroot.'/') === 0) {
 481                         $dir = substr($dir, strlen($CFG->dirroot));
 482                         $module = array('name'=>$component, 'fullpath'=>"$dir/module.js", 'requires' => array());
 483                     }
 484                 }
 485             }
 486         }
 487
 488         return $module;
 489     }
 490
 491     /**
 492      * Append YUI3 module to default YUI3 JS loader.
 493      * The structure of module array is described at http://developer.yahoo.com/yui/3/yui/:
 494      * @param string|array $module name of module (details are autodetected), or full module specification as array
 495      * @return void
 496      */
 497     public function js_module($module) {
 498         global $CFG;
 499
 500         if (empty($module)) {
 501             throw new coding_exception('Missing YUI3 module name or full description.');
 502         }
 503
 504         if (is_string($module)) {
 505             $module = $this->find_module($module);
 506         }
 507
 508         if (empty($module) or empty($module['name']) or empty($module['fullpath'])) {
 509             throw new coding_exception('Missing YUI3 module details.');
 510         }
 511
 512         // Don't load this module if we already have, no need to!
 513         if ($this->js_module_loaded($module['name'])) {
 514             if (debugging('', DEBUG_DEVELOPER)) {
 515                 $this->debug_moduleloadstacktraces[$module['name']][] = format_backtrace(debug_backtrace());
 516             }
 517             return;
 518         }
 519
 520         $module['fullpath'] = $this->js_fix_url($module['fullpath'])->out(false);
 521         // add all needed strings
 522         if (!empty($module['strings'])) {
 523             foreach ($module['strings'] as $string) {
 524                 $identifier = $string[0];
 525                 $component = isset($string[1]) ? $string[1] : 'moodle';
 526                 $a = isset($string[2]) ? $string[2] : null;
 527                 $this->string_for_js($identifier, $component, $a);
 528             }
 529         }
 530         unset($module['strings']);
 531
 532         // Process module requirements and attempt to load each. This allows
 533         // moodle modules to require each other.
 534         if (!empty($module['requires'])){
 535             foreach ($module['requires'] as $requirement) {
 536                 $rmodule = $this->find_module($requirement);
 537                 if (is_array($rmodule)) {
 538                     $this->js_module($rmodule);
 539                 }
 540             }
 541         }
 542
 543         if ($this->headdone) {
 544             $this->extramodules[$module['name']] = $module;
 545         } else {
 546             $this->M_yui_loader->modules[$module['name']] = $module;
 547         }
 548         if (debugging('', DEBUG_DEVELOPER)) {
 549             if (!array_key_exists($module['name'], $this->debug_moduleloadstacktraces)) {
 550                 $this->debug_moduleloadstacktraces[$module['name']] = array();
 551             }
 552             $this->debug_moduleloadstacktraces[$module['name']][] = format_backtrace(debug_backtrace());
 553         }
 554     }
 555
 556     /**
 557      * Returns true if the module has already been loaded.
 558      *
 559      * @param string|array $modulename
 560      * @return bool True if the module has already been loaded
 561      */
 562     protected function js_module_loaded($module) {
 563         if (is_string($module)) {
 564             $modulename = $module;
 565         } else {
 566             $modulename = $module['name'];
 567         }
 568         return array_key_exists($modulename, $this->M_yui_loader->modules) ||
 569                array_key_exists($modulename, $this->extramodules);
 570     }
 571
 572     /**
 573      * Returns the stacktraces from loading js modules.
 574      * @return array
 575      */
 576     public function get_loaded_modules() {
 577         return $this->debug_moduleloadstacktraces;
 578     }
 579
 580     /**
 581      * Ensure that the specified CSS file is linked to from this page.
 582      *
 583      * Because stylesheet links must go in the <head> part of the HTML, you must call
 584      * this function before {@link get_head_code()} is called. That normally means before
 585      * the call to print_header. If you call it when it is too late, an exception
 586      * will be thrown.
 587      *
 588      * Even if a particular style sheet is requested more than once, it will only
 589      * be linked to once.
 590      *
 591      * Please note use of this feature is strongly discouraged,
 592      * it is suitable only for places where CSS is submitted directly by teachers.
 593      * (Students must not be allowed to submit any external CSS because it may
 594      * contain embedded javascript!). Example of correct use is mod/data.
 595      *
 596      * @param string $stylesheet The path to the .css file, relative to $CFG->wwwroot.
 597      *   For example:
 598      *      $PAGE->requires->css('mod/data/css.php?d='.$data->id);
 599      */
 600     public function css($stylesheet) {
 601         global $CFG;
 602
 603         if ($this->headdone) {
 604             throw new coding_exception('Cannot require a CSS file after &lt;head> has been printed.', $stylesheet);
 605         }
 606
 607         if ($stylesheet instanceof moodle_url) {
 608             // ok
 609         } else if (strpos($stylesheet, '/') === 0) {
 610             $stylesheet = new moodle_url($CFG->httpswwwroot.$stylesheet);
 611         } else {
 612             throw new coding_exception('Invalid stylesheet parameter.', $stylesheet);
 613         }
 614
 615         $this->cssurls[$stylesheet->out()] = $stylesheet; // overrides
 616     }
 617
 618     /**
 619      * Add theme stylkesheet to page - do not use from plugin code,
 620      * this should be called only from the core renderer!
 621      * @param moodle_url $stylesheet
 622      * @return void
 623      */
 624     public function css_theme(moodle_url $stylesheet) {
 625         $this->cssthemeurls[] = $stylesheet;
 626     }
 627
 628     /**
 629      * Ensure that a skip link to a given target is printed at the top of the <body>.
 630      *
 631      * You must call this function before {@link get_top_of_body_code()}, (if not, an exception
 632      * will be thrown). That normally means you must call this before the call to print_header.
 633      *
 634      * If you ask for a particular skip link to be printed, it is then your responsibility
 635      * to ensure that the appropriate <a name="..."> tag is printed in the body of the
 636      * page, so that the skip link goes somewhere.
 637      *
 638      * Even if a particular skip link is requested more than once, only one copy of it will be output.
 639      *
 640      * @param $target the name of anchor this link should go to. For example 'maincontent'.
 641      * @param $linktext The text to use for the skip link. Normally get_string('skipto', 'access', ...);
 642      */
 643     public function skip_link_to($target, $linktext) {
 644         if ($this->topofbodydone) {
 645             debugging('Page header already printed, can not add skip links any more, code needs to be fixed.');
 646             return;
 647         }
 648         $this->skiplinks[$target] = $linktext;
 649     }
 650
 651     /**
 652      * !!!DEPRECATED!!! please use js_init_call() if possible
 653      * Ensure that the specified JavaScript function is called from an inline script
 654      * somewhere on this page.
 655      *
 656      * By default the call will be put in a script tag at the
 657      * end of the page after initialising Y instance, since this gives best page-load
 658      * performance and allows you to use YUI3 library.
 659      *
 660      * If you request that a particular function is called several times, then
 661      * that is what will happen (unlike linking to a CSS or JS file, where only
 662      * one link will be output).
 663      *
 664      * The main benefit of the method is the automatic encoding of all function parameters.
 665      *
 666      * @param string $function the name of the JavaScritp function to call. Can
 667      *      be a compound name like 'Y.Event.purgeElement'. Can also be
 668      *      used to create and object by using a 'function name' like 'new user_selector'.
 669      * @param array $arguments and array of arguments to be passed to the function.
 670      *      When generating the function call, this will be escaped using json_encode,
 671      *      so passing objects and arrays should work.
 672      * @param bool $ondomready
 673      * @param int $delay
 674      * @return void
 675      */
 676     public function js_function_call($function, array $arguments = null, $ondomready = false, $delay = 0) {
 677         $where = $ondomready ? 'ondomready' : 'normal';
 678         $this->jscalls[$where][] = array($function, $arguments, $delay);
 679     }
 680
 681     /**
 682      * Adds a call to make use of a YUI gallery module. DEPRECATED DO NOT USE!!!
 683      *
 684      * @deprecated DO NOT USE
 685      *
 686      * @param string|array $modules One or more gallery modules to require
 687      * @param string $version
 688      * @param string $function
 689      * @param array $arguments
 690      * @param bool $ondomready
 691      */
 692     public function js_gallery_module($modules, $version, $function, array $arguments = null, $ondomready = false) {
 693         global $CFG;
 694         debugging('This function will be removed before 2.0 is released please change it from js_gallery_module to yui_module', DEBUG_DEVELOPER);
 695         $this->yui_module($modules, $function, $arguments, $version, $ondomready);
 696     }
 697
 698     /**
 699      * Creates a JavaScript function call that requires one or more modules to be loaded
 700      *
 701      * This function can be used to include all of the standard YUI module types within JavaScript:
 702      *     - YUI3 modules    [node, event, io]
 703      *     - YUI2 modules    [yui2-*]
 704      *     - Moodle modules  [moodle-*]
 705      *     - Gallery modules [gallery-*]
 706      *
 707      * @param array|string $modules One or more modules
 708      * @param string $function The function to call once modules have been loaded
 709      * @param array $arguments An array of arguments to pass to the function
 710      * @param string $galleryversion The gallery version to use
 711      * @param bool $ondomready
 712      */
 713     public function yui_module($modules, $function, array $arguments = null, $galleryversion = '2010.04.08-12-35', $ondomready = false) {
 714         global $CFG;
 715
 716         if (!is_array($modules)) {
 717             $modules = array($modules);
 718         }
 719         if (empty($CFG->useexternalyui) || true) {
 720             // We need to set the M.yui.galleryversion to the correct version
 721             $jscode = 'M.yui.galleryversion='.json_encode($galleryversion).';';
 722         } else {
 723             // Set Y's config.gallery to the version
 724             $jscode = 'Y.config.gallery='.json_encode($galleryversion).';';
 725         }
 726         $jscode .= 'Y.use('.join(',', array_map('json_encode', $modules)).',function() {'.js_writer::function_call($function, $arguments).'})';
 727         if ($ondomready) {
 728             $jscode = "Y.on('domready', function() { $jscode });";
 729         }
 730         $this->jsinitcode[] = $jscode;
 731     }
 732
 733     /**
 734      * Ensure that the specified JavaScript function is called from an inline script
 735      * from page footer.
 736      *
 737      * @param string $function the name of the JavaScritp function to with init code,
 738      *      usually something like 'M.mod_mymodule.init'
 739      * @param array $extraarguments and array of arguments to be passed to the function.
 740      *      The first argument is always the YUI3 Y instance with all required dependencies
 741      *      already loaded.
 742      * @param bool $ondomready wait for dom ready (helps with some IE problems when modifying DOM)
 743      * @param array $module JS module specification array
 744      * @return void
 745      */
 746     public function js_init_call($function, array $extraarguments = null, $ondomready = false, array $module = null) {
 747         $jscode = js_writer::function_call_with_Y($function, $extraarguments);
 748         if (!$module) {
 749             // detect module automatically
 750             if (preg_match('/M\.([a-z0-9]+_[^\.]+)/', $function, $matches)) {
 751                 $module = $this->find_module($matches[1]);
 752             }
 753         }
 754
 755         $this->js_init_code($jscode, $ondomready, $module);
 756     }
 757
 758     /**
 759      * Add short static javascript code fragment to page footer.
 760      * This is intended primarily for loading of js modules and initialising page layout.
 761      * Ideally the JS code fragment should be stored in plugin renderer so that themes
 762      * may override it.
 763      * @param string $jscode
 764      * @param bool $ondomready wait for dom ready (helps with some IE problems when modifying DOM)
 765      * @param array $module JS module specification array
 766      * @return void
 767      */
 768     public function js_init_code($jscode, $ondomready = false, array $module = null) {
 769         $jscode = trim($jscode, " ;\n"). ';';
 770
 771         if ($module) {
 772             $this->js_module($module);
 773             $modulename = $module['name'];
 774             $jscode = "Y.use('$modulename', function(Y) { $jscode });";
 775         }
 776
 777         if ($ondomready) {
 778             $jscode = "Y.on('domready', function() { $jscode });";
 779         }
 780
 781         $this->jsinitcode[] = $jscode;
 782     }
 783
 784     /**
 785      * Make a language string available to JavaScript.
 786      *
 787      * All the strings will be available in a M.str object in the global namespace.
 788      * So, for example, after a call to $PAGE->requires->string_for_js('course', 'moodle');
 789      * then the JavaScript variable M.str.moodle.course will be 'Course', or the
 790      * equivalent in the current language.
 791      *
 792      * The arguments to this function are just like the arguments to get_string
 793      * except that $component is not optional, and there are some aspects to consider
 794      * when the string contains {$a} placeholder.
 795      *
 796      * If the string does not contain any {$a} placeholder, you can simply use
 797      * M.str.component.identifier to obtain it. If you prefer, you can call
 798      * M.util.get_string(identifier, component) to get the same result.
 799      *
 800      * If you need to use {$a} placeholders, there are two options. Either the
 801      * placeholder should be substituted in PHP on server side or it should
 802      * be substituted in Javascript at client side.
 803      *
 804      * To substitute the placeholder at server side, just provide the required
 805      * value for the placeholder when you require the string. Because each string
 806      * is only stored once in the JavaScript (based on $identifier and $module)
 807      * you cannot get the same string with two different values of $a. If you try,
 808      * an exception will be thrown. Once the placeholder is substituted, you can
 809      * use M.str or M.util.get_string() as shown above:
 810      *
 811      *     // require the string in PHP and replace the placeholder
 812      *     $PAGE->requires->string_for_js('fullnamedisplay', 'moodle', $USER);
 813      *     // use the result of the substitution in Javascript
 814      *     alert(M.str.moodle.fullnamedisplay);
 815      *
 816      * To substitute the placeholder at client side, use M.util.get_string()
 817      * function. It implements the same logic as {@see get_string()}:
 818      *
 819      *     // require the string in PHP but keep {$a} as it is
 820      *     $PAGE->requires->string_for_js('fullnamedisplay', 'moodle');
 821      *     // provide the values on the fly in Javascript
 822      *     user = { firstname : 'Harry', lastname : 'Potter' }
 823      *     alert(M.util.get_string('fullnamedisplay', 'moodle', user);
 824      *
 825      * If you do need the same string expanded with different $a values in PHP
 826      * on server side, then the solution is to put them in your own data structure
 827      * (e.g. and array) that you pass to JavaScript with {@link data_for_js()}.
 828      *
 829      * @param string $identifier the desired string.
 830      * @param string $module the language file to look in.
 831      * @param mixed $a any extra data to add into the string (optional).
 832      */
 833     public function string_for_js($identifier, $component, $a = NULL) {
 834         $string = get_string($identifier, $component, $a);
 835         if (!$component) {
 836             throw new coding_exception('The $module parameter is required for page_requirements_manager::string_for_js.');
 837         }
 838         if (isset($this->stringsforjs[$component][$identifier]) && $this->stringsforjs[$component][$identifier] !== $string) {
 839             throw new coding_exception("Attempt to re-define already required string '$identifier' " .
 840                     "from lang file '$component'. Did you already ask for it with a different \$a? {$this->stringsforjs[$component][$identifier]} !== $string");
 841         }
 842         $this->stringsforjs[$component][$identifier] = $string;
 843     }
 844
 845     /**
 846      * Make an array of language strings available for JS
 847      *
 848      * This function calls the above function {@link string_for_js()} for each requested
 849      * string in the $identifiers array that is passed to the argument for a single module
 850      * passed in $module.
 851      *
 852      * <code>
 853      * $PAGE->requires->strings_for_js(array('one', 'two', 'three'), 'mymod', array('a', null, 3));
 854      *
 855      * // The above is identitical to calling
 856      *
 857      * $PAGE->requires->string_for_js('one', 'mymod', 'a');
 858      * $PAGE->requires->string_for_js('two', 'mymod');
 859      * $PAGE->requires->string_for_js('three', 'mymod', 3);
 860      * </code>
 861      *
 862      * @param array $identifiers An array of desired strings
 863      * @param string $component The module to load for
 864      * @param mixed $a This can either be a single variable that gets passed as extra
 865      *         information for every string or it can be an array of mixed data where the
 866      *         key for the data matches that of the identifier it is meant for.
 867      *
 868      */
 869     public function strings_for_js($identifiers, $component, $a=NULL) {
 870         foreach ($identifiers as $key => $identifier) {
 871             if (is_array($a) && array_key_exists($key, $a)) {
 872                 $extra = $a[$key];
 873             } else {
 874                 $extra = $a;
 875             }
 876             $this->string_for_js($identifier, $component, $extra);
 877         }
 878     }
 879
 880     /**
 881      * !!!!!!DEPRECATED!!!!!! please use js_init_call() for everything now.
 882      *
 883      * Make some data from PHP available to JavaScript code.
 884      *
 885      * For example, if you call
 886      * <pre>
 887      *      $PAGE->requires->data_for_js('mydata', array('name' => 'Moodle'));
 888      * </pre>
 889      * then in JavsScript mydata.name will be 'Moodle'.
 890      * @param string $variable the the name of the JavaScript variable to assign the data to.
 891      *      Will probably work if you use a compound name like 'mybuttons.button[1]', but this
 892      *      should be considered an experimental feature.
 893      * @param mixed $data The data to pass to JavaScript. This will be escaped using json_encode,
 894      *      so passing objects and arrays should work.
 895      * @param bool $inhead initialise in head
 896      * @return void
 897      */
 898     public function data_for_js($variable, $data, $inhead=false) {
 899         $where = $inhead ? 'head' : 'footer';
 900         $this->jsinitvariables[$where][] = array($variable, $data);
 901     }
 902
 903     /**
 904      * Creates a YUI event handler.
 905      *
 906      * @param mixed $selector standard YUI selector for elemnts, may be array or string, element id is in the form "#idvalue"
 907      * @param string $event A valid DOM event (click, mousedown, change etc.)
 908      * @param string $function The name of the function to call
 909      * @param array  $arguments An optional array of argument parameters to pass to the function
 910      * @return void
 911      */
 912     public function event_handler($selector, $event, $function, array $arguments = null) {
 913         $this->eventhandlers[] = array('selector'=>$selector, 'event'=>$event, 'function'=>$function, 'arguments'=>$arguments);
 914     }
 915
 916     /**
 917      * Returns code needed for registering of event handlers.
 918      * @return string JS code
 919      */
 920     protected function get_event_handler_code() {
 921         $output = '';
 922         foreach ($this->eventhandlers as $h) {
 923             $output .= js_writer::event_handler($h['selector'], $h['event'], $h['function'], $h['arguments']);
 924         }
 925         return $output;
 926     }
 927
 928     /**
 929      * Get the inline JavaScript code that need to appear in a particular place.
 930      * @return bool $ondomready
 931      */
 932     protected function get_javascript_code($ondomready) {
 933         $where = $ondomready ? 'ondomready' : 'normal';
 934         $output = '';
 935         if ($this->jscalls[$where]) {
 936             foreach ($this->jscalls[$where] as $data) {
 937                 $output .= js_writer::function_call($data[0], $data[1], $data[2]);
 938             }
 939             if (!empty($ondomready)) {
 940                 $output = "    Y.on('domready', function() {\n$output\n    });";
 941             }
 942         }
 943         return $output;
 944     }
 945
 946     /**
 947      * Returns js code to be executed when Y is available.
 948      * @return unknown_type
 949      */
 950     protected function get_javascript_init_code() {
 951         if (count($this->jsinitcode)) {
 952             return implode("\n", $this->jsinitcode) . "\n";
 953         }
 954         return '';
 955     }
 956
 957     /**
 958      * Returns basic YUI3 JS loading code.
 959      * YUI3 is using autoloading of both CSS and JS code.
 960      *
 961      * Major benefit of this compared to standard js/csss loader is much improved
 962      * caching, better browser cache utilisation, much fewer http requests.
 963      *
 964      * @return string
 965      */
 966     protected function get_yui3lib_headcode() {
 967         $code = $this->yui3loader->tags();
 968         // unfortunately yui loader does not produce xhtml strict code, so let's fix it for now
 969         $code = str_replace('&amp;', '&', $code);
 970         $code = str_replace('&', '&amp;', $code);
 971         return $code;
 972     }
 973
 974     /**
 975      * Returns basic YUI2 JS loading code.
 976      * It can be called manually at any time.
 977      * If called manually the result needs to be output using echo().
 978      *
 979      * Major benefit of this compared to standard js loader is much improved
 980      * caching, better browser cache utilisation, much fewer http requests.
 981      *
 982      * All YUI2 CSS is loaded automatically.
 983      *
 984      * @return string JS embedding code
 985      */
 986     public function get_yui2lib_code() {
 987         global $CFG;
 988
 989         if ($this->headdone) {
 990             $code = $this->yui2loader->script();
 991         } else {
 992             $code = $this->yui2loader->script();
 993             if ($this->yui2loader->combine) {
 994                 $skinurl = $this->yui2loader->comboBase . $CFG->yui2version . '/build/assets/skins/sam/skin.css';
 995             } else {
 996                 $skinurl = $this->yui2loader->base . 'assets/skins/sam/skin.css';
 997             }
 998             // please note this is a temporary hack until we fully migrate to later YUI3 that has all the widgets
 999             $attributes = array('rel'=>'stylesheet', 'type'=>'text/css', 'href'=>$skinurl);
1000             $code .= "\n" . html_writer::empty_tag('link', $attributes) . "\n";
1001         }
1002         $code = str_replace('&amp;', '&', $code);
1003         $code = str_replace('&', '&amp;', $code);
1004         return $code;
1005     }
1006
1007     /**
1008      * Returns html tags needed for inclusion of theme CSS
1009      * @return string
1010      */
1011     protected function get_css_code() {
1012         // First of all the theme CSS, then any custom CSS
1013         // Please note custom CSS is strongly discouraged,
1014         // because it can not be overridden by themes!
1015         // It is suitable only for things like mod/data which accepts CSS from teachers.
1016         $attributes = array('rel'=>'stylesheet', 'type'=>'text/css');
1017
1018         // This line of code may look funny but it is currently required in order
1019         // to avoid MASSIVE display issues in Internet Explorer.
1020         // As of IE8 + YUI3.1.1 the reference stylesheet (firstthemesheet) gets
1021         // ignored whenever another resource is added until such time as a redraw
1022         // is forced, usually by moving the mouse over the affected element.
1023         $code = html_writer::tag('script', '/** Required in order to fix style inclusion problems in IE with YUI **/', array('id'=>'firstthemesheet', 'type'=>'text/css'));
1024
1025         $urls = $this->cssthemeurls + $this->cssurls;
1026         foreach ($urls as $url) {
1027             $attributes['href'] = $url;
1028             $code .= html_writer::empty_tag('link', $attributes) . "\n";
1029             // this id is needed in first sheet only so that theme may override YUI sheets laoded on the fly
1030             unset($attributes['id']);
1031         }
1032
1033         return $code;
1034     }
1035
1036     /**
1037      * Adds extra modules specified after printing of page header
1038      */
1039     protected function get_extra_modules_code() {
1040         if (empty($this->extramodules)) {
1041             return '';
1042         }
1043         return html_writer::script(js_writer::function_call('M.yui.add_module', array($this->extramodules)));
1044     }
1045
1046     /**
1047      * Generate any HTML that needs to go inside the <head> tag.
1048      *
1049      * Normally, this method is called automatically by the code that prints the
1050      * <head> tag. You should not normally need to call it in your own code.
1051      *
1052      * @return string the HTML code to to inside the <head> tag.
1053      */
1054     public function get_head_code(moodle_page $page, core_renderer $renderer) {
1055         global $CFG;
1056
1057         // note: the $page and $output are not stored here because it would
1058         // create circular references in memory which prevents garbage collection
1059         $this->init_requirements_data($page, $renderer);
1060
1061         // yui3 JS and CSS is always loaded first - it is cached in browser
1062         $output = $this->get_yui3lib_headcode();
1063
1064         // BC: load basic YUI2 for now, all yui2 things should be loaded via Y.use('yui2-oldmodulename')
1065         $output .= $this->get_yui2lib_code();
1066
1067         // now theme CSS + custom CSS in this specific order
1068         $output .= $this->get_css_code();
1069
1070         // set up global YUI3 loader object - this should contain all code needed by plugins
1071         // note: in JavaScript just use "YUI(M.yui.loader).use('overlay', function(Y) { .... });"
1072         // this needs to be done before including any other script
1073         $js = "var M = {}; M.yui = {}; var moodleConfigFn = function(me) {var p = me.path, b = me.name.replace(/^moodle-/,'').split('-', 3), n = b.pop();if (/(skin|core)/.test(n)) {n = b.pop();me.type = 'css';};me.path = b.join('-')+'/'+n+'/'+n+'.'+me.type;}; var galleryConfigFn = function(me) {var p = me.path,v=M.yui.galleryversion,f;if(/-(skin|core)/.test(me.name)) {me.type = 'css';p = p.replace(/-(skin|core)/, '').replace(/\.js/, '.css').split('/'), f = p.pop().replace(/(\-(min|debug))/, '');if (/-skin/.test(me.name)) {p.splice(p.length,0,v,'assets','skins','sam', f);} else {p.splice(p.length,0,v,'assets', f);};} else {p = p.split('/'), f = p.pop();p.splice(p.length,0,v, f);};me.path = p.join('/');};\n";
1074         $js .= js_writer::set_variable('M.yui.loader', $this->M_yui_loader, false) . "\n";
1075         $js .= js_writer::set_variable('M.cfg', $this->M_cfg, false);
1076         $js = str_replace('"@GALLERYCONFIGFN@"', 'galleryConfigFn', $js);
1077         $js = str_replace('"@MOODLECONFIGFN@"', 'moodleConfigFn', $js);
1078
1079         $output .= html_writer::script($js);
1080
1081         // link our main JS file, all core stuff should be there
1082         $output .= html_writer::script('', $this->js_fix_url('/lib/javascript-static.js'));
1083
1084         // add variables
1085         if ($this->jsinitvariables['head']) {
1086             $js = '';
1087             foreach ($this->jsinitvariables['head'] as $data) {
1088                 list($var, $value) = $data;
1089                 $js .= js_writer::set_variable($var, $value, true);
1090             }
1091             $output .= html_writer::script($js);
1092         }
1093
1094         // all the other linked things from HEAD - there should be as few as possible
1095         if ($this->jsincludes['head']) {
1096             foreach ($this->jsincludes['head'] as $url) {
1097                 $output .= html_writer::script('', $url);
1098             }
1099         }
1100
1101         // mark head sending done, it is not possible to anything there
1102         $this->headdone = true;
1103
1104         return $output;
1105     }
1106
1107     /**
1108      * Generate any HTML that needs to go at the start of the <body> tag.
1109      *
1110      * Normally, this method is called automatically by the code that prints the
1111      * <head> tag. You should not normally need to call it in your own code.
1112      *
1113      * @return string the HTML code to go at the start of the <body> tag.
1114      */
1115     public function get_top_of_body_code() {
1116         // first the skip links
1117         $links = '';
1118         $attributes = array('class'=>'skip');
1119         foreach ($this->skiplinks as $url => $text) {
1120             $attributes['href'] = '#' . $url;
1121             $links .= html_writer::tag('a', $text, $attributes);
1122         }
1123         $output = html_writer::tag('div', $links, array('class'=>'skiplinks')) . "\n";
1124
1125         // then the clever trick for hiding of things not needed when JS works
1126         $output .= html_writer::script("document.body.className += ' jsenabled';") . "\n";
1127         $this->topofbodydone = true;
1128         return $output;
1129     }
1130
1131     /**
1132      * Generate any HTML that needs to go at the end of the page.
1133      *
1134      * Normally, this method is called automatically by the code that prints the
1135      * page footer. You should not normally need to call it in your own code.
1136      *
1137      * @return string the HTML code to to at the end of the page.
1138      */
1139     public function get_end_code() {
1140         global $CFG;
1141         // add other requested modules
1142         $output = $this->get_extra_modules_code();
1143
1144         // add missing YUI2 YUI - to be removed once we convert everything to YUI3!
1145         $output .= $this->get_yui2lib_code();
1146
1147         // all the other linked scripts - there should be as few as possible
1148         if ($this->jsincludes['footer']) {
1149             foreach ($this->jsincludes['footer'] as $url) {
1150                 $output .= html_writer::script('', $url);
1151             }
1152         }
1153
1154         // add all needed strings
1155         if (!empty($this->stringsforjs)) {
1156             $output .= html_writer::script(js_writer::set_variable('M.str', $this->stringsforjs));
1157         }
1158
1159         // add variables
1160         if ($this->jsinitvariables['footer']) {
1161             $js = '';
1162             foreach ($this->jsinitvariables['footer'] as $data) {
1163                 list($var, $value) = $data;
1164                 $js .= js_writer::set_variable($var, $value, true);
1165             }
1166             $output .= html_writer::script($js);
1167         }
1168
1169         $inyuijs = $this->get_javascript_code(false);
1170         $ondomreadyjs = $this->get_javascript_code(true);
1171         $jsinit = $this->get_javascript_init_code();
1172         $handlersjs = $this->get_event_handler_code();
1173
1174         // there is no global Y, make sure it is available in your scope
1175         $js = "YUI(M.yui.loader).use('node', function(Y) {\n{$inyuijs}{$ondomreadyjs}{$jsinit}{$handlersjs}\n});";
1176
1177         $output .= html_writer::script($js);
1178
1179         return $output;
1180     }
1181
1182     /**
1183      * @return boolean Have we already output the code in the <head> tag?
1184      */
1185     public function is_head_done() {
1186         return $this->headdone;
1187     }
1188
1189     /**
1190      * @return boolean Have we already output the code at the start of the <body> tag?
1191      */
1192     public function is_top_of_body_done() {
1193         return $this->topofbodydone;
1194     }
1195 }
1196
1197 /**
1198  * Invalidate all server and client side JS caches.
1199  * @return void
1200  */
1201 function js_reset_all_caches() {
1202     global $CFG;
1203     require_once("$CFG->libdir/filelib.php");
1204
1205     set_config('jsrev', empty($CFG->jsrev) ? 1 : $CFG->jsrev+1);
1206     fulldelete("$CFG->dataroot/cache/js");
1207 }
1208