lib/outputrequirementslib.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  * Library functions to facilitate the use of JavaScript in Moodle.
  19  *
  20  * Note: you can find history of this file in lib/ajax/ajaxlib.php
  21  *
  22  * @copyright 2009 Tim Hunt, 2010 Petr Skoda
  23  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  24  * @package core
  25  * @category output
  26  */
  27
  28 defined('MOODLE_INTERNAL') || die();
  29
  30 /**
  31  * This class tracks all the things that are needed by the current page.
  32  *
  33  * Normally, the only instance of this  class you will need to work with is the
  34  * one accessible via $PAGE->requires.
  35  *
  36  * Typical usage would be
  37  * <pre>
  38  *     $PAGE->requires->js_init_call('M.mod_forum.init_view');
  39  * </pre>
  40  *
  41  * It also supports obsoleted coding style withouth YUI3 modules.
  42  * <pre>
  43  *     $PAGE->requires->css('/mod/mymod/userstyles.php?id='.$id); // not overridable via themes!
  44  *     $PAGE->requires->js('/mod/mymod/script.js');
  45  *     $PAGE->requires->js('/mod/mymod/small_but_urgent.js', true);
  46  *     $PAGE->requires->js_function_call('init_mymod', array($data), true);
  47  * </pre>
  48  *
  49  * There are some natural restrictions on some methods. For example, {@link css()}
  50  * can only be called before the <head> tag is output. See the comments on the
  51  * individual methods for details.
  52  *
  53  * @copyright 2009 Tim Hunt, 2010 Petr Skoda
  54  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  55  * @since Moodle 2.0
  56  * @package core
  57  * @category output
  58  */
  59 class page_requirements_manager {
  60
  61     /**
  62      * @var array List of string available from JS
  63      */
  64     protected $stringsforjs = array();
  65
  66     /**
  67      * @var array List of JS variables to be initialised
  68      */
  69     protected $jsinitvariables = array('head'=>array(), 'footer'=>array());
  70
  71     /**
  72      * @var array Included JS scripts
  73      */
  74     protected $jsincludes = array('head'=>array(), 'footer'=>array());
  75
  76     /**
  77      * @var array List of needed function calls
  78      */
  79     protected $jscalls = array('normal'=>array(), 'ondomready'=>array());
  80
  81     /**
  82      * @var array List of skip links, those are needed for accessibility reasons
  83      */
  84     protected $skiplinks = array();
  85
  86     /**
  87      * @var array Javascript code used for initialisation of page, it should
  88      * be relatively small
  89      */
  90     protected $jsinitcode = array();
  91
  92     /**
  93      * @var array of moodle_url Theme sheets, initialised only from core_renderer
  94      */
  95     protected $cssthemeurls = array();
  96
  97     /**
  98      * @var array of moodle_url List of custom theme sheets, these are strongly discouraged!
  99      * Useful mostly only for CSS submitted by teachers that is not part of the theme.
 100      */
 101     protected $cssurls = array();
 102
 103     /**
 104      * @var array List of requested event handlers
 105      */
 106     protected $eventhandlers = array();
 107
 108     /**
 109      * @var array Extra modules
 110      */
 111     protected $extramodules = array();
 112
 113     /**
 114      * @var bool Flag indicated head stuff already printed
 115      */
 116     protected $headdone = false;
 117
 118     /**
 119      * @var bool Flag indicating top of body already printed
 120      */
 121     protected $topofbodydone = false;
 122
 123     /**
 124      * @var YAHOO_util_Loader YUI PHPLoader instance responsible for YUI2 loading
 125      * from PHP only
 126      */
 127     protected $yui2loader;
 128
 129     /**
 130      * @var stdClass YUI PHPLoader instance responsible for YUI3 loading from PHP only
 131      */
 132     protected $yui3loader;
 133
 134     /**
 135      * @var stdClass YUI loader information for YUI3 loading from javascript
 136      */
 137     protected $M_yui_loader;
 138
 139     /**
 140      * @var array Some config vars exposed in JS, please no secret stuff there
 141      */
 142     protected $M_cfg;
 143
 144     /**
 145      * @var array Stores debug backtraces from when JS modules were included in the page
 146      */
 147     protected $debug_moduleloadstacktraces = array();
 148
 149     /**
 150      * Page requirements constructor.
 151      */
 152     public function __construct() {
 153         global $CFG;
 154
 155         require_once("$CFG->libdir/yui/phploader/phploader/loader.php");
 156
 157         $this->yui3loader = new stdClass();
 158         $this->yui2loader = new YAHOO_util_Loader($CFG->yui2version);
 159
 160         // set up some loader options
 161         if (debugging('', DEBUG_DEVELOPER)) {
 162             $this->yui3loader->filter = YUI_RAW; // for more detailed logging info use YUI_DEBUG here
 163             $this->yui2loader->filter = YUI_RAW; // for more detailed logging info use YUI_DEBUG here
 164             $this->yui2loader->allowRollups = false;
 165         } else {
 166             $this->yui3loader->filter = null;
 167             $this->yui2loader->filter = null;
 168         }
 169         if (!empty($CFG->useexternalyui) and strpos($CFG->httpswwwroot, 'https:') !== 0) {
 170             $this->yui3loader->base = 'http://yui.yahooapis.com/' . $CFG->yui3version . '/build/';
 171             $this->yui2loader->base = 'http://yui.yahooapis.com/' . $CFG->yui2version . '/build/';
 172             $this->yui3loader->comboBase = 'http://yui.yahooapis.com/combo?';
 173             $this->yui2loader->comboBase = 'http://yui.yahooapis.com/combo?';
 174         } else {
 175             $this->yui3loader->base = $CFG->httpswwwroot . '/lib/yui/'. $CFG->yui3version . '/build/';
 176             $this->yui2loader->base = $CFG->httpswwwroot . '/lib/yui/'. $CFG->yui2version . '/build/';
 177             $this->yui3loader->comboBase = $CFG->httpswwwroot . '/theme/yui_combo.php?';
 178             $this->yui2loader->comboBase = $CFG->httpswwwroot . '/theme/yui_combo.php?';
 179         }
 180
 181         // enable combo loader? this significantly helps with caching and performance!
 182         $this->yui3loader->combine = !empty($CFG->yuicomboloading);
 183         $this->yui2loader->combine = !empty($CFG->yuicomboloading);
 184
 185         if (empty($CFG->cachejs)) {
 186             $jsrev = -1;
 187         } else if (empty($CFG->jsrev)) {
 188             $jsrev = 1;
 189         } else {
 190             $jsrev = $CFG->jsrev;
 191         }
 192
 193         // set up JS YUI loader helper object
 194         $this->M_yui_loader = new stdClass();
 195         $this->M_yui_loader->base         = $this->yui3loader->base;
 196         $this->M_yui_loader->comboBase    = $this->yui3loader->comboBase;
 197         $this->M_yui_loader->combine      = $this->yui3loader->combine;
 198         $this->M_yui_loader->filter       = (string)$this->yui3loader->filter;
 199         $this->M_yui_loader->insertBefore = 'firstthemesheet';
 200         $this->M_yui_loader->modules      = array();
 201         $this->M_yui_loader->groups       = array(
 202             'moodle' => array(
 203                 'name' => 'moodle',
 204                 'base' => $CFG->httpswwwroot . '/theme/yui_combo.php?moodle/'.$jsrev.'/',
 205                 'comboBase' => $CFG->httpswwwroot . '/theme/yui_combo.php?',
 206                 'combine' => $this->yui3loader->combine,
 207                 'filter' => '',
 208                 'ext' => false,
 209                 'root' => 'moodle/'.$jsrev.'/', // Add the rev to the root path so that we can control caching
 210                 'patterns' => array(
 211                     'moodle-' => array(
 212                         'group' => 'moodle',
 213                         'configFn' => '@MOODLECONFIGFN@'
 214                     ),
 215                     'root' => 'moodle'
 216                 )
 217             ),
 218             'local' => array(
 219                 'name' => 'gallery',
 220                 'base' => $CFG->wwwroot.'/lib/yui/gallery/',
 221                 'comboBase' => $CFG->httpswwwroot . '/theme/yui_combo.php?',
 222                 'combine' => $this->yui3loader->combine,
 223                 'filter' => $this->M_yui_loader->filter,
 224                 'ext' => false,
 225                 'root' => 'gallery/',
 226                 'patterns' => array(
 227                     'gallery-' => array(
 228                         'group' => 'gallery',
 229                         'configFn' => '@GALLERYCONFIGFN@',
 230                     ),
 231                     'root' => 'gallery'
 232                 )
 233             )
 234         );
 235         $this->add_yui2_modules(); // adds loading info for all YUI2 modules
 236         $this->js_module($this->find_module('core_filepicker'));
 237         $this->js_module($this->find_module('core_dock'));
 238
 239     }
 240
 241     /**
 242      * This method adds yui2 modules into the yui3 JS loader so that they can
 243      * be easily included for use in JavaScript.
 244      */
 245     protected function add_yui2_modules() {
 246         //note: this function is definitely not perfect, because
 247         //      it adds tons of markup into each page, but it can be
 248         //      abstracted into separate JS file with proper headers
 249         global $CFG;
 250
 251         $GLOBALS['yui_current'] = array();
 252         require($CFG->libdir.'/yui/phploader/lib/meta/config_'.$CFG->yui2version.'.php');
 253         $info = $GLOBALS['yui_current'];
 254         unset($GLOBALS['yui_current']);
 255
 256         if (empty($CFG->yuicomboloading)) {
 257             $urlbase = $this->yui2loader->base;
 258         } else {
 259             $urlbase = $this->yui2loader->comboBase.$CFG->yui2version.'/build/';
 260         }
 261
 262         $modules = array();
 263         $ignored = array(); // list of CSS modules that are not needed
 264         foreach ($info['moduleInfo'] as $name => $module) {
 265             if ($module['type'] === 'css') {
 266                 $ignored[$name] = true;
 267             } else {
 268                 $modules['yui2-'.$name] = $module;
 269             }
 270         }
 271         foreach ($modules as $name=>$module) {
 272             $module['fullpath'] = $urlbase.$module['path']; // fix path to point to correct location
 273             unset($module['path']);
 274             unset($module['skinnable']); // we load all YUI2 css automatically, this prevents weird missing css loader problems
 275             foreach(array('requires', 'optional', 'supersedes') as $fixme) {
 276                 if (!empty($module[$fixme])) {
 277                     $fixed = false;
 278                     foreach ($module[$fixme] as $key=>$dep) {
 279                         if (isset($ignored[$dep])) {
 280                             unset($module[$fixme][$key]);
 281                             $fixed = true;
 282                         } else {
 283                             $module[$fixme][$key] = 'yui2-'.$dep;
 284                         }
 285                     }
 286                     if ($fixed) {
 287                         $module[$fixme] = array_merge($module[$fixme]); // fix keys
 288                     }
 289                 }
 290             }
 291             $this->M_yui_loader->modules[$name] = $module;
 292             if (debugging('', DEBUG_DEVELOPER)) {
 293                 if (!array_key_exists($name, $this->debug_moduleloadstacktraces)) {
 294                     $this->debug_moduleloadstacktraces[$name] = array();
 295                 }
 296                 $this->debug_moduleloadstacktraces[$name][] = format_backtrace(debug_backtrace());
 297             }
 298         }
 299     }
 300
 301     /**
 302      * Initialise with the bits of JavaScript that every Moodle page should have.
 303      *
 304      * @param moodle_page $page
 305      * @param core_renderer $renderer
 306      */
 307     protected function init_requirements_data(moodle_page $page, core_renderer $renderer) {
 308         global $CFG;
 309
 310         // JavaScript should always work with $CFG->httpswwwroot rather than $CFG->wwwroot.
 311         // Otherwise, in some situations, users will get warnings about insecure content
 312         // on secure pages from their web browser.
 313
 314         $this->M_cfg = array(
 315             'wwwroot'             => $CFG->httpswwwroot, // Yes, really. See above.
 316             'sesskey'             => sesskey(),
 317             'loadingicon'         => $renderer->pix_url('i/loading_small', 'moodle')->out(false),
 318             'themerev'            => theme_get_revision(),
 319             'theme'               => $page->theme->name,
 320             'jsrev'               => ((empty($CFG->cachejs) or empty($CFG->jsrev)) ? -1 : $CFG->jsrev),
 321         );
 322         if (debugging('', DEBUG_DEVELOPER)) {
 323             $this->M_cfg['developerdebug'] = true;
 324             $this->yui2_lib('logger');
 325         }
 326
 327         // accessibility stuff
 328         $this->skip_link_to('maincontent', get_string('tocontent', 'access'));
 329
 330         // to be removed soon
 331         $this->yui2_lib('dom');        // at least javascript-static.js needs to be migrated to YUI3
 332
 333         $this->string_for_js('confirmation', 'admin');
 334         $this->string_for_js('cancel', 'moodle');
 335         $this->string_for_js('yes', 'moodle');
 336
 337         if ($page->pagelayout === 'frametop') {
 338             $this->js_init_call('M.util.init_frametop');
 339         }
 340     }
 341
 342     /**
 343      * Ensure that the specified JavaScript file is linked to from this page.
 344      *
 345      * NOTE: This function is to be used in rare cases only, please store your JS in module.js file
 346      * and use $PAGE->requires->js_init_call() instead.
 347      *
 348      * By default the link is put at the end of the page, since this gives best page-load performance.
 349      *
 350      * Even if a particular script is requested more than once, it will only be linked
 351      * to once.
 352      *
 353      * @param string|moodle_url $url The path to the .js file, relative to $CFG->dirroot / $CFG->wwwroot.
 354      *      For example '/mod/mymod/customscripts.js'; use moodle_url for external scripts
 355      * @param bool $inhead initialise in head
 356      */
 357     public function js($url, $inhead = false) {
 358         $url = $this->js_fix_url($url);
 359         $where = $inhead ? 'head' : 'footer';
 360         $this->jsincludes[$where][$url->out()] = $url;
 361     }
 362
 363     /**
 364      * Ensure that the specified YUI2 library file, and all its required dependencies,
 365      * are linked to from this page.
 366      *
 367      * By default the link is put at the end of the page, since this gives best page-load
 368      * performance. Optional dependencies are not loaded automatically - if you want
 369      * them you will need to load them first with other calls to this method.
 370      *
 371      * Even if a particular library is requested more than once (perhaps as a dependency
 372      * of other libraries) it will only be linked to once.
 373      *
 374      * The library is leaded as soon as possible, if $OUTPUT->header() not used yet it
 375      * is put into the page header, otherwise it is loaded in the page footer.
 376      *
 377      * @param string|array $libname the name of the YUI2 library you require. For example 'autocomplete'.
 378      */
 379     public function yui2_lib($libname) {
 380         $libnames = (array)$libname;
 381         foreach ($libnames as $lib) {
 382             $this->yui2loader->load($lib);
 383         }
 384     }
 385
 386     /**
 387      * Returns the actual url through which a script is served.
 388      *
 389      * @param moodle_url|string $url full moodle url, or shortened path to script
 390      * @return moodle_url
 391      */
 392     protected function js_fix_url($url) {
 393         global $CFG;
 394
 395         if ($url instanceof moodle_url) {
 396             return $url;
 397         } else if (strpos($url, '/') === 0) {
 398             if (debugging()) {
 399                 // check file existence only when in debug mode
 400                 if (!file_exists($CFG->dirroot . strtok($url, '?'))) {
 401                     throw new coding_exception('Attempt to require a JavaScript file that does not exist.', $url);
 402                 }
 403             }
 404             if (!empty($CFG->cachejs) and !empty($CFG->jsrev) and strpos($url, '/lib/editor/') !== 0 and substr($url, -3) === '.js') {
 405                 return new moodle_url($CFG->httpswwwroot.'/lib/javascript.php', array('file'=>$url, 'rev'=>$CFG->jsrev));
 406             } else {
 407                 return new moodle_url($CFG->httpswwwroot.$url);
 408             }
 409         } else {
 410             throw new coding_exception('Invalid JS url, it has to be shortened url starting with / or moodle_url instance.', $url);
 411         }
 412     }
 413
 414     /**
 415      * Find out if JS module present and return details.
 416      *
 417      * @param string $component name of component in frankenstyle, ex: core_group, mod_forum
 418      * @return array description of module or null if not found
 419      */
 420     protected function find_module($component) {
 421         global $CFG;
 422
 423         $module = null;
 424
 425         if (strpos($component, 'core_') === 0) {
 426             // must be some core stuff - list here is not complete, this is just the stuff used from multiple places
 427             // so that we do nto have to repeat the definition of these modules over and over again
 428             switch($component) {
 429                 case 'core_filepicker':
 430                     $module = array('name'     => 'core_filepicker',
 431                                     'fullpath' => '/repository/filepicker.js',
 432                                     'requires' => array('base', 'node', 'node-event-simulate', 'json', 'async-queue', 'io-base', 'io-upload-iframe', 'io-form', 'yui2-button', 'yui2-container', 'yui2-layout', 'yui2-menu', 'yui2-treeview', 'yui2-dragdrop', 'yui2-cookie'),
 433                                     'strings'  => array(array('add', 'repository'), array('back', 'repository'), array('cancel', 'moodle'), array('close', 'repository'),
 434                                                         array('cleancache', 'repository'), array('copying', 'repository'), array('date', 'repository'), array('downloadsucc', 'repository'),
 435                                                         array('emptylist', 'repository'), array('error', 'repository'), array('federatedsearch', 'repository'),
 436                                                         array('filenotnull', 'repository'), array('getfile', 'repository'), array('help', 'moodle'), array('iconview', 'repository'),
 437                                                         array('invalidjson', 'repository'), array('linkexternal', 'repository'), array('listview', 'repository'),
 438                                                         array('loading', 'repository'), array('login', 'repository'), array('logout', 'repository'), array('noenter', 'repository'),
 439                                                         array('noresult', 'repository'), array('manageurl', 'repository'), array('popup', 'repository'), array('preview', 'repository'),
 440                                                         array('refresh', 'repository'), array('save', 'repository'), array('saveas', 'repository'), array('saved', 'repository'),
 441                                                         array('saving', 'repository'), array('search', 'repository'), array('searching', 'repository'), array('size', 'repository'),
 442                                                         array('submit', 'repository'), array('sync', 'repository'), array('title', 'repository'), array('upload', 'repository'),
 443                                                         array('uploading', 'repository'), array('xhtmlerror', 'repository'),
 444                                                         array('cancel'), array('chooselicense', 'repository'), array('author', 'repository'),array('next', 'moodle'),
 445                                                         array('ok', 'moodle'), array('error', 'moodle'), array('info', 'moodle'), array('norepositoriesavailable', 'repository'), array('norepositoriesexternalavailable', 'repository'),
 446                                                         array('nofilesattached', 'repository'), array('filepicker', 'repository'),
 447                                                         array('nofilesavailable', 'repository'), array('overwrite', 'repository'),
 448                                                         array('renameto', 'repository'), array('fileexists', 'repository'),
 449                                                         array('fileexistsdialogheader', 'repository'), array('fileexistsdialog_editor', 'repository'),
 450                                                         array('fileexistsdialog_filemanager', 'repository')
 451                                                     ));
 452                     break;
 453                 case 'core_comment':
 454                     $module = array('name'     => 'core_comment',
 455                                     'fullpath' => '/comment/comment.js',
 456                                     'requires' => array('base', 'io-base', 'node', 'json', 'yui2-animation', 'overlay'),
 457                                     'strings' => array(array('confirmdeletecomments', 'admin'), array('yes', 'moodle'), array('no', 'moodle'))
 458                                 );
 459                     break;
 460                 case 'core_role':
 461                     $module = array('name'     => 'core_role',
 462                                     'fullpath' => '/admin/roles/module.js',
 463                                     'requires' => array('node', 'cookie'));
 464                     break;
 465                 case 'core_completion':
 466                     $module = array('name'     => 'core_completion',
 467                                     'fullpath' => '/course/completion.js');
 468                     break;
 469                 case 'core_dock':
 470                     $module = array('name'     => 'core_dock',
 471                                     'fullpath' => '/blocks/dock.js',
 472                                     'requires' => array('base', 'node', 'event-custom', 'event-mouseenter', 'event-resize'),
 473                                     'strings' => array(array('addtodock', 'block'),array('undockitem', 'block'),array('undockall', 'block'),array('thisdirectionvertical', 'langconfig')));
 474                     break;
 475                 case 'core_message':
 476                     $module = array('name'     => 'core_message',
 477                                     'requires' => array('base', 'node', 'event', 'node-event-simulate'),
 478                                     'fullpath' => '/message/module.js');
 479                     break;
 480                 case 'core_group':
 481                     $module = array('name'     => 'core_group',
 482                                     'fullpath' => '/group/module.js',
 483                                     'requires' => array('node', 'overlay', 'event-mouseenter'));
 484                     break;
 485                 case 'core_question_engine':
 486                     $module = array('name'     => 'core_question_engine',
 487                                     'fullpath' => '/question/qengine.js',
 488                                     'requires' => array('node', 'event'));
 489                     break;
 490                 case 'core_rating':
 491                     $module = array('name'     => 'core_rating',
 492                                     'fullpath' => '/rating/module.js',
 493                                     'requires' => array('node', 'event', 'overlay', 'io-base', 'json'));
 494                     break;
 495                 case 'core_filetree':
 496                     $module = array('name'     => 'core_filetree',
 497                                     'fullpath' => '/files/module.js',
 498                                     'requires' => array('node', 'event', 'overlay', 'io-base', 'json', 'yui2-treeview'));
 499                     break;
 500                 case 'core_dndupload':
 501                     $module = array('name'     => 'core_dndupload',
 502                                     'fullpath' => '/lib/form/dndupload.js',
 503                                     'requires' => array('node', 'event', 'json'),
 504                                     'strings'  => array(array('uploadformlimit', 'moodle'), array('droptoupload', 'moodle'), array('maxfilesreached', 'moodle'), array('dndenabled_inbox', 'moodle')));
 505                     break;
 506             }
 507
 508         } else {
 509             if ($dir = get_component_directory($component)) {
 510                 if (file_exists("$dir/module.js")) {
 511                     if (strpos($dir, $CFG->dirroot.'/') === 0) {
 512                         $dir = substr($dir, strlen($CFG->dirroot));
 513                         $module = array('name'=>$component, 'fullpath'=>"$dir/module.js", 'requires' => array());
 514                     }
 515                 }
 516             }
 517         }
 518
 519         return $module;
 520     }
 521
 522     /**
 523      * Append YUI3 module to default YUI3 JS loader.
 524      * The structure of module array is described at {@link http://developer.yahoo.com/yui/3/yui/}
 525      *
 526      * @param string|array $module name of module (details are autodetected), or full module specification as array
 527      * @return void
 528      */
 529     public function js_module($module) {
 530         global $CFG;
 531
 532         if (empty($module)) {
 533             throw new coding_exception('Missing YUI3 module name or full description.');
 534         }
 535
 536         if (is_string($module)) {
 537             $module = $this->find_module($module);
 538         }
 539
 540         if (empty($module) or empty($module['name']) or empty($module['fullpath'])) {
 541             throw new coding_exception('Missing YUI3 module details.');
 542         }
 543
 544         // Don't load this module if we already have, no need to!
 545         if ($this->js_module_loaded($module['name'])) {
 546             if (debugging('', DEBUG_DEVELOPER)) {
 547                 $this->debug_moduleloadstacktraces[$module['name']][] = format_backtrace(debug_backtrace());
 548             }
 549             return;
 550         }
 551
 552         $module['fullpath'] = $this->js_fix_url($module['fullpath'])->out(false);
 553         // add all needed strings
 554         if (!empty($module['strings'])) {
 555             foreach ($module['strings'] as $string) {
 556                 $identifier = $string[0];
 557                 $component = isset($string[1]) ? $string[1] : 'moodle';
 558                 $a = isset($string[2]) ? $string[2] : null;
 559                 $this->string_for_js($identifier, $component, $a);
 560             }
 561         }
 562         unset($module['strings']);
 563
 564         // Process module requirements and attempt to load each. This allows
 565         // moodle modules to require each other.
 566         if (!empty($module['requires'])){
 567             foreach ($module['requires'] as $requirement) {
 568                 $rmodule = $this->find_module($requirement);
 569                 if (is_array($rmodule)) {
 570                     $this->js_module($rmodule);
 571                 }
 572             }
 573         }
 574
 575         if ($this->headdone) {
 576             $this->extramodules[$module['name']] = $module;
 577         } else {
 578             $this->M_yui_loader->modules[$module['name']] = $module;
 579         }
 580         if (debugging('', DEBUG_DEVELOPER)) {
 581             if (!array_key_exists($module['name'], $this->debug_moduleloadstacktraces)) {
 582                 $this->debug_moduleloadstacktraces[$module['name']] = array();
 583             }
 584             $this->debug_moduleloadstacktraces[$module['name']][] = format_backtrace(debug_backtrace());
 585         }
 586     }
 587
 588     /**
 589      * Returns true if the module has already been loaded.
 590      *
 591      * @param string|array $module
 592      * @return bool True if the module has already been loaded
 593      */
 594     protected function js_module_loaded($module) {
 595         if (is_string($module)) {
 596             $modulename = $module;
 597         } else {
 598             $modulename = $module['name'];
 599         }
 600         return array_key_exists($modulename, $this->M_yui_loader->modules) ||
 601                array_key_exists($modulename, $this->extramodules);
 602     }
 603
 604     /**
 605      * Returns the stacktraces from loading js modules.
 606      * @return array
 607      */
 608     public function get_loaded_modules() {
 609         return $this->debug_moduleloadstacktraces;
 610     }
 611
 612     /**
 613      * Ensure that the specified CSS file is linked to from this page.
 614      *
 615      * Because stylesheet links must go in the <head> part of the HTML, you must call
 616      * this function before {@link get_head_code()} is called. That normally means before
 617      * the call to print_header. If you call it when it is too late, an exception
 618      * will be thrown.
 619      *
 620      * Even if a particular style sheet is requested more than once, it will only
 621      * be linked to once.
 622      *
 623      * Please note use of this feature is strongly discouraged,
 624      * it is suitable only for places where CSS is submitted directly by teachers.
 625      * (Students must not be allowed to submit any external CSS because it may
 626      * contain embedded javascript!). Example of correct use is mod/data.
 627      *
 628      * @param string $stylesheet The path to the .css file, relative to $CFG->wwwroot.
 629      *   For example:
 630      *      $PAGE->requires->css('mod/data/css.php?d='.$data->id);
 631      */
 632     public function css($stylesheet) {
 633         global $CFG;
 634
 635         if ($this->headdone) {
 636             throw new coding_exception('Cannot require a CSS file after &lt;head> has been printed.', $stylesheet);
 637         }
 638
 639         if ($stylesheet instanceof moodle_url) {
 640             // ok
 641         } else if (strpos($stylesheet, '/') === 0) {
 642             $stylesheet = new moodle_url($CFG->httpswwwroot.$stylesheet);
 643         } else {
 644             throw new coding_exception('Invalid stylesheet parameter.', $stylesheet);
 645         }
 646
 647         $this->cssurls[$stylesheet->out()] = $stylesheet; // overrides
 648     }
 649
 650     /**
 651      * Add theme stylkesheet to page - do not use from plugin code,
 652      * this should be called only from the core renderer!
 653      *
 654      * @param moodle_url $stylesheet
 655      * @return void
 656      */
 657     public function css_theme(moodle_url $stylesheet) {
 658         $this->cssthemeurls[] = $stylesheet;
 659     }
 660
 661     /**
 662      * Ensure that a skip link to a given target is printed at the top of the <body>.
 663      *
 664      * You must call this function before {@link get_top_of_body_code()}, (if not, an exception
 665      * will be thrown). That normally means you must call this before the call to print_header.
 666      *
 667      * If you ask for a particular skip link to be printed, it is then your responsibility
 668      * to ensure that the appropriate <a name="..."> tag is printed in the body of the
 669      * page, so that the skip link goes somewhere.
 670      *
 671      * Even if a particular skip link is requested more than once, only one copy of it will be output.
 672      *
 673      * @param $target the name of anchor this link should go to. For example 'maincontent'.
 674      * @param $linktext The text to use for the skip link. Normally get_string('skipto', 'access', ...);
 675      */
 676     public function skip_link_to($target, $linktext) {
 677         if ($this->topofbodydone) {
 678             debugging('Page header already printed, can not add skip links any more, code needs to be fixed.');
 679             return;
 680         }
 681         $this->skiplinks[$target] = $linktext;
 682     }
 683
 684     /**
 685      * !!!DEPRECATED!!! please use js_init_call() if possible
 686      * Ensure that the specified JavaScript function is called from an inline script
 687      * somewhere on this page.
 688      *
 689      * By default the call will be put in a script tag at the
 690      * end of the page after initialising Y instance, since this gives best page-load
 691      * performance and allows you to use YUI3 library.
 692      *
 693      * If you request that a particular function is called several times, then
 694      * that is what will happen (unlike linking to a CSS or JS file, where only
 695      * one link will be output).
 696      *
 697      * The main benefit of the method is the automatic encoding of all function parameters.
 698      *
 699      * @param string $function the name of the JavaScritp function to call. Can
 700      *      be a compound name like 'Y.Event.purgeElement'. Can also be
 701      *      used to create and object by using a 'function name' like 'new user_selector'.
 702      * @param array $arguments and array of arguments to be passed to the function.
 703      *      When generating the function call, this will be escaped using json_encode,
 704      *      so passing objects and arrays should work.
 705      * @param bool $ondomready If tru the function is only called when the dom is
 706      *      ready for manipulation.
 707      * @param int $delay The delay before the function is called.
 708      */
 709     public function js_function_call($function, array $arguments = null, $ondomready = false, $delay = 0) {
 710         $where = $ondomready ? 'ondomready' : 'normal';
 711         $this->jscalls[$where][] = array($function, $arguments, $delay);
 712     }
 713
 714     /**
 715      * Adds a call to make use of a YUI gallery module. DEPRECATED DO NOT USE!!!
 716      *
 717      * @deprecated DO NOT USE
 718      *
 719      * @param string|array $modules One or more gallery modules to require
 720      * @param string $version
 721      * @param string $function
 722      * @param array $arguments
 723      * @param bool $ondomready
 724      */
 725     public function js_gallery_module($modules, $version, $function, array $arguments = null, $ondomready = false) {
 726         global $CFG;
 727         debugging('This function will be removed before 2.0 is released please change it from js_gallery_module to yui_module', DEBUG_DEVELOPER);
 728         $this->yui_module($modules, $function, $arguments, $version, $ondomready);
 729     }
 730
 731     /**
 732      * Creates a JavaScript function call that requires one or more modules to be loaded
 733      *
 734      * This function can be used to include all of the standard YUI module types within JavaScript:
 735      *     - YUI3 modules    [node, event, io]
 736      *     - YUI2 modules    [yui2-*]
 737      *     - Moodle modules  [moodle-*]
 738      *     - Gallery modules [gallery-*]
 739      *
 740      * @param array|string $modules One or more modules
 741      * @param string $function The function to call once modules have been loaded
 742      * @param array $arguments An array of arguments to pass to the function
 743      * @param string $galleryversion The gallery version to use
 744      * @param bool $ondomready
 745      */
 746     public function yui_module($modules, $function, array $arguments = null, $galleryversion = '2010.04.08-12-35', $ondomready = false) {
 747         global $CFG;
 748
 749         if (!is_array($modules)) {
 750             $modules = array($modules);
 751         }
 752         if (empty($CFG->useexternalyui) || true) {
 753             // We need to set the M.yui.galleryversion to the correct version
 754             $jscode = 'M.yui.galleryversion='.json_encode($galleryversion).';';
 755         } else {
 756             // Set Y's config.gallery to the version
 757             $jscode = 'Y.config.gallery='.json_encode($galleryversion).';';
 758         }
 759         $jscode .= 'Y.use('.join(',', array_map('json_encode', convert_to_array($modules))).',function() {'.js_writer::function_call($function, $arguments).'});';
 760         if ($ondomready) {
 761             $jscode = "Y.on('domready', function() { $jscode });";
 762         }
 763         $this->jsinitcode[] = $jscode;
 764     }
 765
 766     /**
 767      * Ensure that the specified JavaScript function is called from an inline script
 768      * from page footer.
 769      *
 770      * @param string $function the name of the JavaScritp function to with init code,
 771      *      usually something like 'M.mod_mymodule.init'
 772      * @param array $extraarguments and array of arguments to be passed to the function.
 773      *      The first argument is always the YUI3 Y instance with all required dependencies
 774      *      already loaded.
 775      * @param bool $ondomready wait for dom ready (helps with some IE problems when modifying DOM)
 776      * @param array $module JS module specification array
 777      */
 778     public function js_init_call($function, array $extraarguments = null, $ondomready = false, array $module = null) {
 779         $jscode = js_writer::function_call_with_Y($function, $extraarguments);
 780         if (!$module) {
 781             // detect module automatically
 782             if (preg_match('/M\.([a-z0-9]+_[^\.]+)/', $function, $matches)) {
 783                 $module = $this->find_module($matches[1]);
 784             }
 785         }
 786
 787         $this->js_init_code($jscode, $ondomready, $module);
 788     }
 789
 790     /**
 791      * Add short static javascript code fragment to page footer.
 792      * This is intended primarily for loading of js modules and initialising page layout.
 793      * Ideally the JS code fragment should be stored in plugin renderer so that themes
 794      * may override it.
 795      * @param string $jscode
 796      * @param bool $ondomready wait for dom ready (helps with some IE problems when modifying DOM)
 797      * @param array $module JS module specification array
 798      */
 799     public function js_init_code($jscode, $ondomready = false, array $module = null) {
 800         $jscode = trim($jscode, " ;\n"). ';';
 801
 802         if ($module) {
 803             $this->js_module($module);
 804             $modulename = $module['name'];
 805             $jscode = "Y.use('$modulename', function(Y) { $jscode });";
 806         }
 807
 808         if ($ondomready) {
 809             $jscode = "Y.on('domready', function() { $jscode });";
 810         }
 811
 812         $this->jsinitcode[] = $jscode;
 813     }
 814
 815     /**
 816      * Make a language string available to JavaScript.
 817      *
 818      * All the strings will be available in a M.str object in the global namespace.
 819      * So, for example, after a call to $PAGE->requires->string_for_js('course', 'moodle');
 820      * then the JavaScript variable M.str.moodle.course will be 'Course', or the
 821      * equivalent in the current language.
 822      *
 823      * The arguments to this function are just like the arguments to get_string
 824      * except that $component is not optional, and there are some aspects to consider
 825      * when the string contains {$a} placeholder.
 826      *
 827      * If the string does not contain any {$a} placeholder, you can simply use
 828      * M.str.component.identifier to obtain it. If you prefer, you can call
 829      * M.util.get_string(identifier, component) to get the same result.
 830      *
 831      * If you need to use {$a} placeholders, there are two options. Either the
 832      * placeholder should be substituted in PHP on server side or it should
 833      * be substituted in Javascript at client side.
 834      *
 835      * To substitute the placeholder at server side, just provide the required
 836      * value for the placeholder when you require the string. Because each string
 837      * is only stored once in the JavaScript (based on $identifier and $module)
 838      * you cannot get the same string with two different values of $a. If you try,
 839      * an exception will be thrown. Once the placeholder is substituted, you can
 840      * use M.str or M.util.get_string() as shown above:
 841      *
 842      *     // require the string in PHP and replace the placeholder
 843      *     $PAGE->requires->string_for_js('fullnamedisplay', 'moodle', $USER);
 844      *     // use the result of the substitution in Javascript
 845      *     alert(M.str.moodle.fullnamedisplay);
 846      *
 847      * To substitute the placeholder at client side, use M.util.get_string()
 848      * function. It implements the same logic as {@link get_string()}:
 849      *
 850      *     // require the string in PHP but keep {$a} as it is
 851      *     $PAGE->requires->string_for_js('fullnamedisplay', 'moodle');
 852      *     // provide the values on the fly in Javascript
 853      *     user = { firstname : 'Harry', lastname : 'Potter' }
 854      *     alert(M.util.get_string('fullnamedisplay', 'moodle', user);
 855      *
 856      * If you do need the same string expanded with different $a values in PHP
 857      * on server side, then the solution is to put them in your own data structure
 858      * (e.g. and array) that you pass to JavaScript with {@link data_for_js()}.
 859      *
 860      * @param string $identifier the desired string.
 861      * @param string $component the language file to look in.
 862      * @param mixed $a any extra data to add into the string (optional).
 863      */
 864     public function string_for_js($identifier, $component, $a = NULL) {
 865         $string = get_string($identifier, $component, $a);
 866         if (!$component) {
 867             throw new coding_exception('The $module parameter is required for page_requirements_manager::string_for_js.');
 868         }
 869         if (isset($this->stringsforjs[$component][$identifier]) && $this->stringsforjs[$component][$identifier] !== $string) {
 870             throw new coding_exception("Attempt to re-define already required string '$identifier' " .
 871                     "from lang file '$component'. Did you already ask for it with a different \$a? {$this->stringsforjs[$component][$identifier]} !== $string");
 872         }
 873         $this->stringsforjs[$component][$identifier] = $string;
 874     }
 875
 876     /**
 877      * Make an array of language strings available for JS
 878      *
 879      * This function calls the above function {@link string_for_js()} for each requested
 880      * string in the $identifiers array that is passed to the argument for a single module
 881      * passed in $module.
 882      *
 883      * <code>
 884      * $PAGE->requires->strings_for_js(array('one', 'two', 'three'), 'mymod', array('a', null, 3));
 885      *
 886      * // The above is identitical to calling
 887      *
 888      * $PAGE->requires->string_for_js('one', 'mymod', 'a');
 889      * $PAGE->requires->string_for_js('two', 'mymod');
 890      * $PAGE->requires->string_for_js('three', 'mymod', 3);
 891      * </code>
 892      *
 893      * @param array $identifiers An array of desired strings
 894      * @param string $component The module to load for
 895      * @param mixed $a This can either be a single variable that gets passed as extra
 896      *         information for every string or it can be an array of mixed data where the
 897      *         key for the data matches that of the identifier it is meant for.
 898      *
 899      */
 900     public function strings_for_js($identifiers, $component, $a=NULL) {
 901         foreach ($identifiers as $key => $identifier) {
 902             if (is_array($a) && array_key_exists($key, $a)) {
 903                 $extra = $a[$key];
 904             } else {
 905                 $extra = $a;
 906             }
 907             $this->string_for_js($identifier, $component, $extra);
 908         }
 909     }
 910
 911     /**
 912      * !!!!!!DEPRECATED!!!!!! please use js_init_call() for everything now.
 913      *
 914      * Make some data from PHP available to JavaScript code.
 915      *
 916      * For example, if you call
 917      * <pre>
 918      *      $PAGE->requires->data_for_js('mydata', array('name' => 'Moodle'));
 919      * </pre>
 920      * then in JavsScript mydata.name will be 'Moodle'.
 921      * @param string $variable the the name of the JavaScript variable to assign the data to.
 922      *      Will probably work if you use a compound name like 'mybuttons.button[1]', but this
 923      *      should be considered an experimental feature.
 924      * @param mixed $data The data to pass to JavaScript. This will be escaped using json_encode,
 925      *      so passing objects and arrays should work.
 926      * @param bool $inhead initialise in head
 927      * @return void
 928      */
 929     public function data_for_js($variable, $data, $inhead=false) {
 930         $where = $inhead ? 'head' : 'footer';
 931         $this->jsinitvariables[$where][] = array($variable, $data);
 932     }
 933
 934     /**
 935      * Creates a YUI event handler.
 936      *
 937      * @param mixed $selector standard YUI selector for elemnts, may be array or string, element id is in the form "#idvalue"
 938      * @param string $event A valid DOM event (click, mousedown, change etc.)
 939      * @param string $function The name of the function to call
 940      * @param array  $arguments An optional array of argument parameters to pass to the function
 941      */
 942     public function event_handler($selector, $event, $function, array $arguments = null) {
 943         $this->eventhandlers[] = array('selector'=>$selector, 'event'=>$event, 'function'=>$function, 'arguments'=>$arguments);
 944     }
 945
 946     /**
 947      * Returns code needed for registering of event handlers.
 948      * @return string JS code
 949      */
 950     protected function get_event_handler_code() {
 951         $output = '';
 952         foreach ($this->eventhandlers as $h) {
 953             $output .= js_writer::event_handler($h['selector'], $h['event'], $h['function'], $h['arguments']);
 954         }
 955         return $output;
 956     }
 957
 958     /**
 959      * Get the inline JavaScript code that need to appear in a particular place.
 960      * @param bool $ondomready
 961      * @return string
 962      */
 963     protected function get_javascript_code($ondomready) {
 964         $where = $ondomready ? 'ondomready' : 'normal';
 965         $output = '';
 966         if ($this->jscalls[$where]) {
 967             foreach ($this->jscalls[$where] as $data) {
 968                 $output .= js_writer::function_call($data[0], $data[1], $data[2]);
 969             }
 970             if (!empty($ondomready)) {
 971                 $output = "    Y.on('domready', function() {\n$output\n    });";
 972             }
 973         }
 974         return $output;
 975     }
 976
 977     /**
 978      * Returns js code to be executed when Y is available.
 979      * @return string
 980      */
 981     protected function get_javascript_init_code() {
 982         if (count($this->jsinitcode)) {
 983             return implode("\n", $this->jsinitcode) . "\n";
 984         }
 985         return '';
 986     }
 987
 988     /**
 989      * Returns basic YUI3 JS loading code.
 990      * YUI3 is using autoloading of both CSS and JS code.
 991      *
 992      * Major benefit of this compared to standard js/csss loader is much improved
 993      * caching, better browser cache utilisation, much fewer http requests.
 994      *
 995      * @return string
 996      */
 997     protected function get_yui3lib_headcode() {
 998         global $CFG;
 999
1000         $code = '';
1001
1002         if ($this->yui3loader->combine) {
1003             $code .= '<link rel="stylesheet" type="text/css" href="'.$this->yui3loader->comboBase
1004                      .$CFG->yui3version.'/build/cssreset/reset-min.css&amp;'
1005                      .$CFG->yui3version.'/build/cssfonts/fonts-min.css&amp;'
1006                      .$CFG->yui3version.'/build/cssgrids/grids-min.css&amp;'
1007                      .$CFG->yui3version.'/build/cssbase/base-min.css" />';
1008             $code .= '<script type="text/javascript" src="'.$this->yui3loader->comboBase.$CFG->yui3version.'/build/yui/yui-min.js"></script>';
1009         } else {
1010             $code .= '<link rel="stylesheet" type="text/css" href="'.$this->yui3loader->base.'cssreset/reset-min.css" />';
1011             $code .= '<link rel="stylesheet" type="text/css" href="'.$this->yui3loader->base.'cssfonts/fonts-min.css" />';
1012             $code .= '<link rel="stylesheet" type="text/css" href="'.$this->yui3loader->base.'cssgrids/grids-min.css" />';
1013             $code .= '<link rel="stylesheet" type="text/css" href="'.$this->yui3loader->base.'cssbase/base-min.css" />';
1014             $code .= '<script type="text/javascript" src="'.$this->yui3loader->base.'yui/yui-min.js"></script>';
1015         }
1016
1017
1018         if ($this->yui3loader->filter === YUI_RAW) {
1019             $code = str_replace('-min.css', '.css', $code);
1020             $code = str_replace('-min.js', '.js', $code);
1021         } else if ($this->yui3loader->filter === YUI_DEBUG) {
1022             $code = str_replace('-min.css', '.css', $code);
1023             $code = str_replace('-min.js', '-debug.js', $code);
1024         }
1025
1026         return $code;
1027     }
1028
1029     /**
1030      * Returns basic YUI2 JS loading code.
1031      * It can be called manually at any time.
1032      * If called manually the result needs to be output using echo().
1033      *
1034      * Major benefit of this compared to standard js loader is much improved
1035      * caching, better browser cache utilisation, much fewer http requests.
1036      *
1037      * All YUI2 CSS is loaded automatically.
1038      *
1039      * @return string JS embedding code
1040      */
1041     public function get_yui2lib_code() {
1042         global $CFG;
1043
1044         if ($this->headdone) {
1045             $code = $this->yui2loader->script();
1046         } else {
1047             $code = $this->yui2loader->script();
1048             if ($this->yui2loader->combine) {
1049                 $skinurl = $this->yui2loader->comboBase . $CFG->yui2version . '/build/assets/skins/sam/skin.css';
1050             } else {
1051                 $skinurl = $this->yui2loader->base . 'assets/skins/sam/skin.css';
1052             }
1053             // please note this is a temporary hack until we fully migrate to later YUI3 that has all the widgets
1054             $attributes = array('rel'=>'stylesheet', 'type'=>'text/css', 'href'=>$skinurl);
1055             $code .= "\n" . html_writer::empty_tag('link', $attributes) . "\n";
1056         }
1057         $code = str_replace('&amp;', '&', $code);
1058         $code = str_replace('&', '&amp;', $code);
1059         return $code;
1060     }
1061
1062     /**
1063      * Returns html tags needed for inclusion of theme CSS
1064      *
1065      * @return string
1066      */
1067     protected function get_css_code() {
1068         // First of all the theme CSS, then any custom CSS
1069         // Please note custom CSS is strongly discouraged,
1070         // because it can not be overridden by themes!
1071         // It is suitable only for things like mod/data which accepts CSS from teachers.
1072         $attributes = array('rel'=>'stylesheet', 'type'=>'text/css');
1073
1074         // This line of code may look funny but it is currently required in order
1075         // to avoid MASSIVE display issues in Internet Explorer.
1076         // As of IE8 + YUI3.1.1 the reference stylesheet (firstthemesheet) gets
1077         // ignored whenever another resource is added until such time as a redraw
1078         // is forced, usually by moving the mouse over the affected element.
1079         $code = html_writer::tag('script', '/** Required in order to fix style inclusion problems in IE with YUI **/', array('id'=>'firstthemesheet', 'type'=>'text/css'));
1080
1081         $urls = $this->cssthemeurls + $this->cssurls;
1082         foreach ($urls as $url) {
1083             $attributes['href'] = $url;
1084             $code .= html_writer::empty_tag('link', $attributes) . "\n";
1085             // this id is needed in first sheet only so that theme may override YUI sheets laoded on the fly
1086             unset($attributes['id']);
1087         }
1088
1089         return $code;
1090     }
1091
1092     /**
1093      * Adds extra modules specified after printing of page header
1094      *
1095      * @return string
1096      */
1097     protected function get_extra_modules_code() {
1098         if (empty($this->extramodules)) {
1099             return '';
1100         }
1101         return html_writer::script(js_writer::function_call('M.yui.add_module', array($this->extramodules)));
1102     }
1103
1104     /**
1105      * Generate any HTML that needs to go inside the <head> tag.
1106      *
1107      * Normally, this method is called automatically by the code that prints the
1108      * <head> tag. You should not normally need to call it in your own code.
1109      *
1110      * @param moodle_page $page
1111      * @param core_renderer $renderer
1112      * @return string the HTML code to to inside the <head> tag.
1113      */
1114     public function get_head_code(moodle_page $page, core_renderer $renderer) {
1115         global $CFG;
1116
1117         // note: the $page and $output are not stored here because it would
1118         // create circular references in memory which prevents garbage collection
1119         $this->init_requirements_data($page, $renderer);
1120
1121         // yui3 JS and CSS is always loaded first - it is cached in browser
1122         $output = $this->get_yui3lib_headcode();
1123
1124         // BC: load basic YUI2 for now, all yui2 things should be loaded via Y.use('yui2-oldmodulename')
1125         $output .= $this->get_yui2lib_code();
1126
1127         // now theme CSS + custom CSS in this specific order
1128         $output .= $this->get_css_code();
1129
1130         // set up global YUI3 loader object - this should contain all code needed by plugins
1131         // note: in JavaScript just use "YUI(M.yui.loader).use('overlay', function(Y) { .... });"
1132         // this needs to be done before including any other script
1133         $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";
1134         $js .= js_writer::set_variable('M.yui.loader', $this->M_yui_loader, false) . "\n";
1135         $js .= js_writer::set_variable('M.cfg', $this->M_cfg, false);
1136         $js = str_replace('"@GALLERYCONFIGFN@"', 'galleryConfigFn', $js);
1137         $js = str_replace('"@MOODLECONFIGFN@"', 'moodleConfigFn', $js);
1138
1139         $output .= html_writer::script($js);
1140
1141         // link our main JS file, all core stuff should be there
1142         $output .= html_writer::script('', $this->js_fix_url('/lib/javascript-static.js'));
1143
1144         // add variables
1145         if ($this->jsinitvariables['head']) {
1146             $js = '';
1147             foreach ($this->jsinitvariables['head'] as $data) {
1148                 list($var, $value) = $data;
1149                 $js .= js_writer::set_variable($var, $value, true);
1150             }
1151             $output .= html_writer::script($js);
1152         }
1153
1154         // all the other linked things from HEAD - there should be as few as possible
1155         if ($this->jsincludes['head']) {
1156             foreach ($this->jsincludes['head'] as $url) {
1157                 $output .= html_writer::script('', $url);
1158             }
1159         }
1160
1161         // mark head sending done, it is not possible to anything there
1162         $this->headdone = true;
1163
1164         return $output;
1165     }
1166
1167     /**
1168      * Generate any HTML that needs to go at the start of the <body> tag.
1169      *
1170      * Normally, this method is called automatically by the code that prints the
1171      * <head> tag. You should not normally need to call it in your own code.
1172      *
1173      * @return string the HTML code to go at the start of the <body> tag.
1174      */
1175     public function get_top_of_body_code() {
1176         // first the skip links
1177         $links = '';
1178         $attributes = array('class'=>'skip');
1179         foreach ($this->skiplinks as $url => $text) {
1180             $attributes['href'] = '#' . $url;
1181             $links .= html_writer::tag('a', $text, $attributes);
1182         }
1183         $output = html_writer::tag('div', $links, array('class'=>'skiplinks')) . "\n";
1184
1185         // then the clever trick for hiding of things not needed when JS works
1186         $output .= html_writer::script("document.body.className += ' jsenabled';") . "\n";
1187         $this->topofbodydone = true;
1188         return $output;
1189     }
1190
1191     /**
1192      * Generate any HTML that needs to go at the end of the page.
1193      *
1194      * Normally, this method is called automatically by the code that prints the
1195      * page footer. You should not normally need to call it in your own code.
1196      *
1197      * @return string the HTML code to to at the end of the page.
1198      */
1199     public function get_end_code() {
1200         global $CFG;
1201         // add other requested modules
1202         $output = $this->get_extra_modules_code();
1203
1204         // add missing YUI2 YUI - to be removed once we convert everything to YUI3!
1205         $output .= $this->get_yui2lib_code();
1206
1207         // all the other linked scripts - there should be as few as possible
1208         if ($this->jsincludes['footer']) {
1209             foreach ($this->jsincludes['footer'] as $url) {
1210                 $output .= html_writer::script('', $url);
1211             }
1212         }
1213
1214         // add all needed strings
1215         if (!empty($this->stringsforjs)) {
1216             $output .= html_writer::script(js_writer::set_variable('M.str', $this->stringsforjs));
1217         }
1218
1219         // add variables
1220         if ($this->jsinitvariables['footer']) {
1221             $js = '';
1222             foreach ($this->jsinitvariables['footer'] as $data) {
1223                 list($var, $value) = $data;
1224                 $js .= js_writer::set_variable($var, $value, true);
1225             }
1226             $output .= html_writer::script($js);
1227         }
1228
1229         $inyuijs = $this->get_javascript_code(false);
1230         $ondomreadyjs = $this->get_javascript_code(true);
1231         $jsinit = $this->get_javascript_init_code();
1232         $handlersjs = $this->get_event_handler_code();
1233
1234         // there is no global Y, make sure it is available in your scope
1235         $js = "YUI(M.yui.loader).use('node', function(Y) {\n{$inyuijs}{$ondomreadyjs}{$jsinit}{$handlersjs}\n});";
1236
1237         $output .= html_writer::script($js);
1238
1239         return $output;
1240     }
1241
1242     /**
1243      * Have we already output the code in the <head> tag?
1244      *
1245      * @return bool
1246      */
1247     public function is_head_done() {
1248         return $this->headdone;
1249     }
1250
1251     /**
1252      * Have we already output the code at the start of the <body> tag?
1253      *
1254      * @return bool
1255      */
1256     public function is_top_of_body_done() {
1257         return $this->topofbodydone;
1258     }
1259 }
1260
1261 /**
1262  * Invalidate all server and client side JS caches.
1263  */
1264 function js_reset_all_caches() {
1265     global $CFG;
1266     require_once("$CFG->libdir/filelib.php");
1267
1268     set_config('jsrev', empty($CFG->jsrev) ? 1 : $CFG->jsrev+1);
1269     fulldelete("$CFG->cachedir/js");
1270 }