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 get_string $a parameters - used for validation only.
  68      */
  69     protected $stringsforjs_as = array();
  70
  71     /**
  72      * @var array List of JS variables to be initialised
  73      */
  74     protected $jsinitvariables = array('head'=>array(), 'footer'=>array());
  75
  76     /**
  77      * @var array Included JS scripts
  78      */
  79     protected $jsincludes = array('head'=>array(), 'footer'=>array());
  80
  81     /**
  82      * @var array List of needed function calls
  83      */
  84     protected $jscalls = array('normal'=>array(), 'ondomready'=>array());
  85
  86     /**
  87      * @var array List of skip links, those are needed for accessibility reasons
  88      */
  89     protected $skiplinks = array();
  90
  91     /**
  92      * @var array Javascript code used for initialisation of page, it should
  93      * be relatively small
  94      */
  95     protected $jsinitcode = array();
  96
  97     /**
  98      * @var array of moodle_url Theme sheets, initialised only from core_renderer
  99      */
 100     protected $cssthemeurls = array();
 101
 102     /**
 103      * @var array of moodle_url List of custom theme sheets, these are strongly discouraged!
 104      * Useful mostly only for CSS submitted by teachers that is not part of the theme.
 105      */
 106     protected $cssurls = array();
 107
 108     /**
 109      * @var array List of requested event handlers
 110      */
 111     protected $eventhandlers = array();
 112
 113     /**
 114      * @var array Extra modules
 115      */
 116     protected $extramodules = array();
 117
 118     /**
 119      * @var bool Flag indicated head stuff already printed
 120      */
 121     protected $headdone = false;
 122
 123     /**
 124      * @var bool Flag indicating top of body already printed
 125      */
 126     protected $topofbodydone = false;
 127
 128     /**
 129      * @var stdClass YUI PHPLoader instance responsible for YUI3 loading from PHP only
 130      */
 131     protected $yui3loader;
 132
 133     /**
 134      * @var YUI_config default YUI loader configuration
 135      */
 136     protected $YUI_config;
 137
 138     /**
 139      * @var array Some config vars exposed in JS, please no secret stuff there
 140      */
 141     protected $M_cfg;
 142
 143     /**
 144      * @var array Stores debug backtraces from when JS modules were included in the page
 145      */
 146     protected $debug_moduleloadstacktraces = array();
 147
 148     /**
 149      * @var array list of requested jQuery plugins
 150      */
 151     protected $jqueryplugins = array();
 152
 153     /**
 154      * @var array list of jQuery plugin overrides
 155      */
 156     protected $jquerypluginoverrides = array();
 157
 158     /**
 159      * Page requirements constructor.
 160      */
 161     public function __construct() {
 162         global $CFG;
 163
 164         // You may need to set up URL rewrite rule because oversized URLs might not be allowed by web server.
 165         $sep = empty($CFG->yuislasharguments) ? '?' : '/';
 166
 167         $this->yui3loader = new stdClass();
 168         $this->YUI_config = new YUI_config();
 169
 170         // Set up some loader options.
 171         if (!empty($CFG->useexternalyui) and strpos($CFG->httpswwwroot, 'https:') !== 0) {
 172             $this->yui3loader->base = 'http://yui.yahooapis.com/' . $CFG->yui3version . '/build/';
 173             $this->yui3loader->comboBase = 'http://yui.yahooapis.com/combo?';
 174         } else {
 175             $this->yui3loader->base = $CFG->httpswwwroot . '/lib/yuilib/'. $CFG->yui3version . '/build/';
 176             $this->yui3loader->comboBase = $CFG->httpswwwroot . '/theme/yui_combo.php'.$sep;
 177         }
 178
 179         // Enable combo loader? This significantly helps with caching and performance!
 180         $this->yui3loader->combine = !empty($CFG->yuicomboloading);
 181
 182         if (empty($CFG->cachejs)) {
 183             $jsrev = -1;
 184         } else if (empty($CFG->jsrev)) {
 185             $jsrev = 1;
 186         } else {
 187             $jsrev = $CFG->jsrev;
 188         }
 189
 190         // Set up JS YUI loader helper object.
 191         $this->YUI_config->base         = $this->yui3loader->base;
 192         $this->YUI_config->comboBase    = $this->yui3loader->comboBase;
 193         $this->YUI_config->combine      = $this->yui3loader->combine;
 194
 195         $configname = $this->YUI_config->set_config_function("if(/-skin|reset|fonts|grids|base/.test(me.name)){me.type='css';me.path=me.path.replace(/\.js/,'.css');me.path=me.path.replace(/\/yui2-skin/,'/assets/skins/sam/yui2-skin');}");
 196         $this->YUI_config->add_group('yui2', array(
 197             // Loader configuration for our 2in3, for now ignores $CFG->useexternalyui.
 198             'base' => $CFG->httpswwwroot . '/lib/yuilib/2in3/' . $CFG->yui2version . '/build/',
 199             'comboBase' => $CFG->httpswwwroot . '/theme/yui_combo.php'.$sep,
 200             'combine' => $this->yui3loader->combine,
 201             'ext' => false,
 202             'root' => '2in3/' . $CFG->yui2version .'/build/',
 203             'patterns' => array(
 204                 'yui2-' => array(
 205                     'group' => 'yui2',
 206                     'configFn' => $configname,
 207                 )
 208             )
 209         ));
 210         $configname = $this->YUI_config->set_config_function("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;if(me.type !== 'css'){me.path=me.path+'-min';};me.path=me.path+'.'+me.type;");
 211         $this->YUI_config->add_group('moodle', array(
 212             'name' => 'moodle',
 213             'base' => $CFG->httpswwwroot . '/theme/yui_combo.php'.$sep.'moodle/'.$jsrev.'/',
 214             'combine' => $this->yui3loader->combine,
 215             'comboBase' => $CFG->httpswwwroot . '/theme/yui_combo.php'.$sep,
 216             'ext' => false,
 217             'root' => 'moodle/'.$jsrev.'/', // Add the rev to the root path so that we can control caching.
 218             'patterns' => array(
 219                 'moodle-' => array(
 220                     'group' => 'moodle',
 221                     'configFn' => $configname,
 222                 )
 223             )
 224         ));
 225
 226         // Set some more loader options applying to groups too.
 227         if (debugging('', DEBUG_DEVELOPER)) {
 228             // When debugging is enabled, we want to load the non-minified (RAW) versions of YUI library modules rather
 229             // than the DEBUG versions as these generally generate too much logging for our purposes.
 230             // However we do want the DEBUG versions of our Moodle-specific modules.
 231             // To debug a YUI-specific issue, change the yui3loader->filter value to DEBUG.
 232             $this->YUI_config->filter = 'RAW';
 233             $this->YUI_config->groups['moodle']['filter'] = 'DEBUG';
 234
 235             // We use the yui3loader->filter setting when writing the YUI3 seed scripts into the header.
 236             $this->yui3loader->filter = $this->YUI_config->filter;
 237             $this->YUI_config->debug = true;
 238         } else {
 239             $this->yui3loader->filter = null;
 240             $this->YUI_config->debug = false;
 241         }
 242
 243         // Add the moodle group's module data.
 244         $this->YUI_config->add_moodle_metadata();
 245
 246         // Every page should include definition of following modules.
 247         $this->js_module($this->find_module('core_filepicker'));
 248         $this->js_module($this->find_module('core_dock'));
 249     }
 250
 251     /**
 252      * Initialise with the bits of JavaScript that every Moodle page should have.
 253      *
 254      * @param moodle_page $page
 255      * @param core_renderer $renderer
 256      */
 257     protected function init_requirements_data(moodle_page $page, core_renderer $renderer) {
 258         global $CFG;
 259
 260         // JavaScript should always work with $CFG->httpswwwroot rather than $CFG->wwwroot.
 261         // Otherwise, in some situations, users will get warnings about insecure content
 262         // on secure pages from their web browser.
 263
 264         $this->M_cfg = array(
 265             'wwwroot'             => $CFG->httpswwwroot, // Yes, really. See above.
 266             'sesskey'             => sesskey(),
 267             'loadingicon'         => $renderer->pix_url('i/loading_small', 'moodle')->out(false),
 268             'themerev'            => theme_get_revision(),
 269             'slasharguments'      => (int)(!empty($CFG->slasharguments)),
 270             'theme'               => $page->theme->name,
 271             'jsrev'               => ((empty($CFG->cachejs) or empty($CFG->jsrev)) ? -1 : $CFG->jsrev),
 272             'svgicons'            => $page->theme->use_svg_icons()
 273         );
 274         if (debugging('', DEBUG_DEVELOPER)) {
 275             $this->M_cfg['developerdebug'] = true;
 276         }
 277
 278         // Accessibility stuff.
 279         $this->skip_link_to('maincontent', get_string('tocontent', 'access'));
 280
 281         // Add strings used on many pages.
 282         $this->string_for_js('confirmation', 'admin');
 283         $this->string_for_js('cancel', 'moodle');
 284         $this->string_for_js('yes', 'moodle');
 285
 286         // Alter links in top frame to break out of frames.
 287         if ($page->pagelayout === 'frametop') {
 288             $this->js_init_call('M.util.init_frametop');
 289         }
 290
 291         // Include block drag/drop if editing is on
 292         if ($page->user_is_editing()) {
 293             $params = array(
 294                 'courseid' => $page->course->id,
 295                 'pagetype' => $page->pagetype,
 296                 'pagelayout' => $page->pagelayout,
 297                 'subpage' => $page->subpage,
 298                 'regions' => $page->blocks->get_regions(),
 299                 'contextid' => $page->context->id,
 300             );
 301             if (!empty($page->cm->id)) {
 302                 $params['cmid'] = $page->cm->id;
 303             }
 304             $page->requires->yui_module('moodle-core-blocks', 'M.core_blocks.init_dragdrop', array($params), null, true);
 305         }
 306     }
 307
 308     /**
 309      * Ensure that the specified JavaScript file is linked to from this page.
 310      *
 311      * NOTE: This function is to be used in RARE CASES ONLY, please store your JS in module.js file
 312      * and use $PAGE->requires->js_init_call() instead or use /yui/ subdirectories for YUI modules.
 313      *
 314      * By default the link is put at the end of the page, since this gives best page-load performance.
 315      *
 316      * Even if a particular script is requested more than once, it will only be linked
 317      * to once.
 318      *
 319      * @param string|moodle_url $url The path to the .js file, relative to $CFG->dirroot / $CFG->wwwroot.
 320      *      For example '/mod/mymod/customscripts.js'; use moodle_url for external scripts
 321      * @param bool $inhead initialise in head
 322      */
 323     public function js($url, $inhead = false) {
 324         $url = $this->js_fix_url($url);
 325         $where = $inhead ? 'head' : 'footer';
 326         $this->jsincludes[$where][$url->out()] = $url;
 327     }
 328
 329     /**
 330      * Request inclusion of jQuery library in the page.
 331      *
 332      * NOTE: this should not be used in official Moodle distribution!
 333      *
 334      * We are going to bundle jQuery 1.9.x until we drop support
 335      * all support for IE 6-8. Use $PAGE->requires->jquery_plugin('migrate')
 336      * for code written for earlier jQuery versions.
 337      *
 338      * {@see http://docs.moodle.org/dev/jQuery}
 339      */
 340     public function jquery() {
 341         $this->jquery_plugin('jquery');
 342     }
 343
 344     /**
 345      * Request inclusion of jQuery plugin.
 346      *
 347      * NOTE: this should not be used in official Moodle distribution!
 348      *
 349      * jQuery plugins are located in plugin/jquery/* subdirectory,
 350      * plugin/jquery/plugins.php lists all available plugins.
 351      *
 352      * Included core plugins:
 353      *   - jQuery UI
 354      *   - jQuery Migrate (useful for code written for previous UI version)
 355      *
 356      * Add-ons may include extra jQuery plugins in jquery/ directory,
 357      * plugins.php file defines the mapping between plugin names and
 358      * necessary page includes.
 359      *
 360      * Examples:
 361      * <code>
 362      *   // file: mod/xxx/view.php
 363      *   $PAGE->requires->jquery();
 364      *   $PAGE->requires->jquery_plugin('ui');
 365      *   $PAGE->requires->jquery_plugin('ui-css');
 366      * </code>
 367      *
 368      * <code>
 369      *   // file: theme/yyy/lib.php
 370      *   function theme_yyy_page_init(moodle_page $page) {
 371      *       $page->requires->jquery();
 372      *       $page->requires->jquery_plugin('ui');
 373      *       $page->requires->jquery_plugin('ui-css');
 374      *   }
 375      * </code>
 376      *
 377      * <code>
 378      *   // file: blocks/zzz/block_zzz.php
 379      *   public function get_required_javascript() {
 380      *       parent::get_required_javascript();
 381      *       $this->page->requires->jquery();
 382      *       $page->requires->jquery_plugin('ui');
 383      *       $page->requires->jquery_plugin('ui-css');
 384      *   }
 385      * </code>
 386      *
 387      * {@see http://docs.moodle.org/dev/jQuery}
 388      *
 389      * @param string $plugin name of the jQuery plugin as defined in jquery/plugins.php
 390      * @param string $component name of the component
 391      * @return bool success
 392      */
 393     public function jquery_plugin($plugin, $component = 'core') {
 394         global $CFG;
 395
 396         if ($this->headdone) {
 397             debugging('Can not add jQuery plugins after starting page output!');
 398             return false;
 399         }
 400
 401         if ($component !== 'core' and in_array($plugin, array('jquery', 'ui', 'ui-css', 'migrate'))) {
 402             debugging("jQuery plugin '$plugin' is included in Moodle core, other components can not use the same name.", DEBUG_DEVELOPER);
 403             $component = 'core';
 404         } else if ($component !== 'core' and strpos($component, '_') === false) {
 405             // Let's normalise the legacy activity names, Frankenstyle rulez!
 406             $component = 'mod_' . $component;
 407         }
 408
 409         if (empty($this->jqueryplugins) and ($component !== 'core' or $plugin !== 'jquery')) {
 410             // Make sure the jQuery itself is always loaded first,
 411             // the order of all other plugins depends on order of $PAGE_>requires->.
 412             $this->jquery_plugin('jquery', 'core');
 413         }
 414
 415         if (isset($this->jqueryplugins[$plugin])) {
 416             // No problem, we already have something, first Moodle plugin to register the jQuery plugin wins.
 417             return true;
 418         }
 419
 420         $componentdir = get_component_directory($component);
 421         if (!file_exists($componentdir) or !file_exists("$componentdir/jquery/plugins.php")) {
 422             debugging("Can not load jQuery plugin '$plugin', missing plugins.php in component '$component'.", DEBUG_DEVELOPER);
 423             return false;
 424         }
 425
 426         $plugins = array();
 427         require("$componentdir/jquery/plugins.php");
 428
 429         if (!isset($plugins[$plugin])) {
 430             debugging("jQuery plugin '$plugin' can not be found in component '$component'.", DEBUG_DEVELOPER);
 431             return false;
 432         }
 433
 434         $this->jqueryplugins[$plugin] = new stdClass();
 435         $this->jqueryplugins[$plugin]->plugin    = $plugin;
 436         $this->jqueryplugins[$plugin]->component = $component;
 437         $this->jqueryplugins[$plugin]->urls      = array();
 438
 439         foreach ($plugins[$plugin]['files'] as $file) {
 440             if (debugging('', DEBUG_DEVELOPER)) {
 441                 if (!file_exists("$componentdir/jquery/$file")) {
 442                     debugging("Invalid file '$file' specified in jQuery plugin '$plugin' in component '$component'");
 443                     continue;
 444                 }
 445                 $file = str_replace('.min.css', '.css', $file);
 446                 $file = str_replace('.min.js', '.js', $file);
 447             }
 448             if (!file_exists("$componentdir/jquery/$file")) {
 449                 debugging("Invalid file '$file' specified in jQuery plugin '$plugin' in component '$component'");
 450                 continue;
 451             }
 452             if (!empty($CFG->slasharguments)) {
 453                 $url = new moodle_url("$CFG->httpswwwroot/theme/jquery.php");
 454                 $url->set_slashargument("/$component/$file");
 455
 456             } else {
 457                 // This is not really good, we need slasharguments for relative links, this means no caching...
 458                 $path = realpath("$componentdir/jquery/$file");
 459                 if (strpos($path, $CFG->dirroot) === 0) {
 460                     $url = $CFG->httpswwwroot.preg_replace('/^'.preg_quote($CFG->dirroot, '/').'/', '', $path);
 461                     $url = new moodle_url($url);
 462                 } else {
 463                     // Bad luck, fix your server!
 464                     debugging("Moodle jQuery integration requires 'slasharguments' setting to be enabled.");
 465                     continue;
 466                 }
 467             }
 468             $this->jqueryplugins[$plugin]->urls[] = $url;
 469         }
 470
 471         return true;
 472     }
 473
 474     /**
 475      * Request replacement of one jQuery plugin by another.
 476      *
 477      * This is useful when themes want to replace the jQuery UI theme,
 478      * the problem is that theme can not prevent others from including the core ui-css plugin.
 479      *
 480      * Example:
 481      *  1/ generate new jQuery UI theme and place it into theme/yourtheme/jquery/
 482      *  2/ write theme/yourtheme/jquery/plugins.php
 483      *  3/ init jQuery from theme
 484      *
 485      * <code>
 486      *   // file theme/yourtheme/lib.php
 487      *   function theme_yourtheme_page_init($page) {
 488      *       $page->requires->jquery_plugin('yourtheme-ui-css', 'theme_yourtheme');
 489      *       $page->requires->jquery_override_plugin('ui-css', 'yourtheme-ui-css');
 490      *   }
 491      * </code>
 492      *
 493      * This code prevents loading of standard 'ui-css' which my be requested by other plugins,
 494      * the 'yourtheme-ui-css' gets loaded only if some other code requires jquery.
 495      *
 496      * {@see http://docs.moodle.org/dev/jQuery}
 497      *
 498      * @param string $oldplugin original plugin
 499      * @param string $newplugin the replacement
 500      */
 501     public function jquery_override_plugin($oldplugin, $newplugin) {
 502         if ($this->headdone) {
 503             debugging('Can not override jQuery plugins after starting page output!');
 504             return;
 505         }
 506         $this->jquerypluginoverrides[$oldplugin] = $newplugin;
 507     }
 508
 509     /**
 510      * Return jQuery related markup for page start.
 511      * @return string
 512      */
 513     protected function get_jquery_headcode() {
 514         if (empty($this->jqueryplugins['jquery'])) {
 515             // If nobody requested jQuery then do not bother to load anything.
 516             // This may be useful for themes that want to override 'ui-css' only if requested by something else.
 517             return '';
 518         }
 519
 520         $included = array();
 521         $urls = array();
 522
 523         foreach ($this->jqueryplugins as $name => $unused) {
 524             if (isset($included[$name])) {
 525                 continue;
 526             }
 527             if (array_key_exists($name, $this->jquerypluginoverrides)) {
 528                 // The following loop tries to resolve the replacements,
 529                 // use max 100 iterations to prevent infinite loop resulting
 530                 // in blank page.
 531                 $cyclic = true;
 532                 $oldname = $name;
 533                 for ($i=0; $i<100; $i++) {
 534                     $name = $this->jquerypluginoverrides[$name];
 535                     if (!array_key_exists($name, $this->jquerypluginoverrides)) {
 536                         $cyclic = false;
 537                         break;
 538                     }
 539                 }
 540                 if ($cyclic) {
 541                     // We can not do much with cyclic references here, let's use the old plugin.
 542                     $name = $oldname;
 543                     debugging("Cyclic overrides detected for jQuery plugin '$name'");
 544
 545                 } else if (empty($name)) {
 546                     // Developer requested removal of the plugin.
 547                     continue;
 548
 549                 } else if (!isset($this->jqueryplugins[$name])) {
 550                     debugging("Unknown jQuery override plugin '$name' detected");
 551                     $name = $oldname;
 552
 553                 } else if (isset($included[$name])) {
 554                     // The plugin was already included, easy.
 555                     continue;
 556                 }
 557             }
 558
 559             $plugin = $this->jqueryplugins[$name];
 560             $urls = array_merge($urls, $plugin->urls);
 561             $included[$name] = true;
 562         }
 563
 564         $output = '';
 565         $attributes = array('rel' => 'stylesheet', 'type' => 'text/css');
 566         foreach ($urls as $url) {
 567             if (preg_match('/\.js$/', $url)) {
 568                 $output .= html_writer::script('', $url);
 569             } else if (preg_match('/\.css$/', $url)) {
 570                 $attributes['href'] = $url;
 571                 $output .= html_writer::empty_tag('link', $attributes) . "\n";
 572             }
 573         }
 574
 575         return $output;
 576     }
 577
 578     /**
 579      * This method was used to load YUI2 libraries into global scope,
 580      * use YUI 2in3 instead. Every YUI2 module is represented as a yui2-*
 581      * sandboxed module in YUI3 code via Y.YUI2. property.
 582      *
 583      * {@see http://tracker.moodle.org/browse/MDL-34741}
 584      *
 585      * @param string|array $libname
 586      * @deprecated since 2.4
 587      */
 588     public function yui2_lib($libname) {
 589         throw new coding_exception('PAGE->yui2_lib() is not available any more, use YUI 2in3 instead, see MDL-34741 for more information.');
 590     }
 591
 592     /**
 593      * Returns the actual url through which a script is served.
 594      *
 595      * @param moodle_url|string $url full moodle url, or shortened path to script
 596      * @return moodle_url
 597      */
 598     protected function js_fix_url($url) {
 599         global $CFG;
 600
 601         if ($url instanceof moodle_url) {
 602             return $url;
 603         } else if (strpos($url, '/') === 0) {
 604             // Fix the admin links if needed.
 605             if ($CFG->admin !== 'admin') {
 606                 if (strpos($url, "/admin/") === 0) {
 607                     $url = preg_replace("|^/admin/|", "/$CFG->admin/", $url);
 608                 }
 609             }
 610             if (debugging()) {
 611                 // Check file existence only when in debug mode.
 612                 if (!file_exists($CFG->dirroot . strtok($url, '?'))) {
 613                     throw new coding_exception('Attempt to require a JavaScript file that does not exist.', $url);
 614                 }
 615             }
 616             if (!empty($CFG->cachejs) and !empty($CFG->jsrev) and $CFG->jsrev > 0 and substr($url, -3) === '.js') {
 617                 if (empty($CFG->slasharguments)) {
 618                     return new moodle_url($CFG->httpswwwroot.'/lib/javascript.php', array('rev'=>$CFG->jsrev, 'jsfile'=>$url));
 619                 } else {
 620                     $returnurl = new moodle_url($CFG->httpswwwroot.'/lib/javascript.php');
 621                     $returnurl->set_slashargument('/'.$CFG->jsrev.$url);
 622                     return $returnurl;
 623                 }
 624             } else {
 625                 return new moodle_url($CFG->httpswwwroot.$url);
 626             }
 627         } else {
 628             throw new coding_exception('Invalid JS url, it has to be shortened url starting with / or moodle_url instance.', $url);
 629         }
 630     }
 631
 632     /**
 633      * Find out if JS module present and return details.
 634      *
 635      * @param string $component name of component in frankenstyle, ex: core_group, mod_forum
 636      * @return array description of module or null if not found
 637      */
 638     protected function find_module($component) {
 639         global $CFG, $PAGE;
 640
 641         $module = null;
 642
 643         if (strpos($component, 'core_') === 0) {
 644             // Must be some core stuff - list here is not complete, this is just the stuff used from multiple places
 645             // so that we do nto have to repeat the definition of these modules over and over again.
 646             switch($component) {
 647                 case 'core_filepicker':
 648                     $module = array('name'     => 'core_filepicker',
 649                                     'fullpath' => '/repository/filepicker.js',
 650                                     'requires' => array('base', 'node', 'node-event-simulate', 'json', 'async-queue', 'io-base', 'io-upload-iframe', 'io-form', 'yui2-treeview', 'panel', 'cookie', 'datatable', 'datatable-sort', 'resize-plugin', 'dd-plugin', 'escape', 'moodle-core_filepicker'),
 651                                     'strings'  => array(array('lastmodified', 'moodle'), array('name', 'moodle'), array('type', 'repository'), array('size', 'repository'),
 652                                                         array('invalidjson', 'repository'), array('error', 'moodle'), array('info', 'moodle'),
 653                                                         array('nofilesattached', 'repository'), array('filepicker', 'repository'), array('logout', 'repository'),
 654                                                         array('nofilesavailable', 'repository'), array('norepositoriesavailable', 'repository'),
 655                                                         array('fileexistsdialogheader', 'repository'), array('fileexistsdialog_editor', 'repository'),
 656                                                         array('fileexistsdialog_filemanager', 'repository'), array('renameto', 'repository'),
 657                                                         array('referencesexist', 'repository')
 658                                                     ));
 659                     break;
 660                 case 'core_comment':
 661                     $module = array('name'     => 'core_comment',
 662                                     'fullpath' => '/comment/comment.js',
 663                                     'requires' => array('base', 'io-base', 'node', 'json', 'yui2-animation', 'overlay'),
 664                                     'strings' => array(array('confirmdeletecomments', 'admin'), array('yes', 'moodle'), array('no', 'moodle'))
 665                                 );
 666                     break;
 667                 case 'core_role':
 668                     $module = array('name'     => 'core_role',
 669                                     'fullpath' => '/admin/roles/module.js',
 670                                     'requires' => array('node', 'cookie'));
 671                     break;
 672                 case 'core_completion':
 673                     $module = array('name'     => 'core_completion',
 674                                     'fullpath' => '/course/completion.js');
 675                     break;
 676                 case 'core_dock':
 677                     $module = array('name'     => 'core_dock',
 678                                     'fullpath' => '/blocks/dock.js',
 679                                     'requires' => array('base', 'node', 'event-custom', 'event-mouseenter', 'event-resize', 'escape'),
 680                                     'strings'  => array(array('addtodock', 'block'),array('undockitem', 'block'),array('dockblock', 'block'),
 681                                                         array('undockblock', 'block'),array('undockall', 'block'),array('thisdirectionvertical', 'langconfig'),
 682                                                         array('hidedockpanel', 'block'),array('hidepanel', 'block')
 683                                                     ));
 684                     break;
 685                 case 'core_message':
 686                     $module = array('name'     => 'core_message',
 687                                     'requires' => array('base', 'node', 'event', 'node-event-simulate'),
 688                                     'fullpath' => '/message/module.js');
 689                     break;
 690                 case 'core_group':
 691                     $module = array('name'     => 'core_group',
 692                                     'fullpath' => '/group/module.js',
 693                                     'requires' => array('node', 'overlay', 'event-mouseenter'));
 694                     break;
 695                 case 'core_question_engine':
 696                     $module = array('name'     => 'core_question_engine',
 697                                     'fullpath' => '/question/qengine.js',
 698                                     'requires' => array('node', 'event'));
 699                     break;
 700                 case 'core_rating':
 701                     $module = array('name'     => 'core_rating',
 702                                     'fullpath' => '/rating/module.js',
 703                                     'requires' => array('node', 'event', 'overlay', 'io-base', 'json'));
 704                     break;
 705                 case 'core_dndupload':
 706                     $module = array('name'     => 'core_dndupload',
 707                                     'fullpath' => '/lib/form/dndupload.js',
 708                                     'requires' => array('node', 'event', 'json', 'core_filepicker'),
 709                                     'strings'  => array(array('uploadformlimit', 'moodle'), array('droptoupload', 'moodle'), array('maxfilesreached', 'moodle'),
 710                                                         array('dndenabled_inbox', 'moodle'), array('fileexists', 'moodle'), array('maxbytesforfile', 'moodle'),
 711                                                         array('maxareabytesreached', 'moodle')
 712                                                     ));
 713                     break;
 714             }
 715
 716         } else {
 717             if ($dir = get_component_directory($component)) {
 718                 if (file_exists("$dir/module.js")) {
 719                     if (strpos($dir, $CFG->dirroot.'/') === 0) {
 720                         $dir = substr($dir, strlen($CFG->dirroot));
 721                         $module = array('name'=>$component, 'fullpath'=>"$dir/module.js", 'requires' => array());
 722                     }
 723                 }
 724             }
 725         }
 726
 727         return $module;
 728     }
 729
 730     /**
 731      * Append YUI3 module to default YUI3 JS loader.
 732      * The structure of module array is described at {@link http://developer.yahoo.com/yui/3/yui/}
 733      *
 734      * @param string|array $module name of module (details are autodetected), or full module specification as array
 735      * @return void
 736      */
 737     public function js_module($module) {
 738         global $CFG;
 739
 740         if (empty($module)) {
 741             throw new coding_exception('Missing YUI3 module name or full description.');
 742         }
 743
 744         if (is_string($module)) {
 745             $module = $this->find_module($module);
 746         }
 747
 748         if (empty($module) or empty($module['name']) or empty($module['fullpath'])) {
 749             throw new coding_exception('Missing YUI3 module details.');
 750         }
 751
 752         // Don't load this module if we already have, no need to!
 753         if ($this->js_module_loaded($module['name'])) {
 754             if (debugging('', DEBUG_DEVELOPER)) {
 755                 $this->debug_moduleloadstacktraces[$module['name']][] = format_backtrace(debug_backtrace());
 756             }
 757             return;
 758         }
 759
 760         $module['fullpath'] = $this->js_fix_url($module['fullpath'])->out(false);
 761         // Add all needed strings.
 762         if (!empty($module['strings'])) {
 763             foreach ($module['strings'] as $string) {
 764                 $identifier = $string[0];
 765                 $component = isset($string[1]) ? $string[1] : 'moodle';
 766                 $a = isset($string[2]) ? $string[2] : null;
 767                 $this->string_for_js($identifier, $component, $a);
 768             }
 769         }
 770         unset($module['strings']);
 771
 772         // Process module requirements and attempt to load each. This allows
 773         // moodle modules to require each other.
 774         if (!empty($module['requires'])){
 775             foreach ($module['requires'] as $requirement) {
 776                 $rmodule = $this->find_module($requirement);
 777                 if (is_array($rmodule)) {
 778                     $this->js_module($rmodule);
 779                 }
 780             }
 781         }
 782
 783         if ($this->headdone) {
 784             $this->extramodules[$module['name']] = $module;
 785         } else {
 786             $this->YUI_config->add_module_config($module['name'], $module);
 787         }
 788         if (debugging('', DEBUG_DEVELOPER)) {
 789             if (!array_key_exists($module['name'], $this->debug_moduleloadstacktraces)) {
 790                 $this->debug_moduleloadstacktraces[$module['name']] = array();
 791             }
 792             $this->debug_moduleloadstacktraces[$module['name']][] = format_backtrace(debug_backtrace());
 793         }
 794     }
 795
 796     /**
 797      * Returns true if the module has already been loaded.
 798      *
 799      * @param string|array $module
 800      * @return bool True if the module has already been loaded
 801      */
 802     protected function js_module_loaded($module) {
 803         if (is_string($module)) {
 804             $modulename = $module;
 805         } else {
 806             $modulename = $module['name'];
 807         }
 808         return array_key_exists($modulename, $this->YUI_config->modules) ||
 809                array_key_exists($modulename, $this->extramodules);
 810     }
 811
 812     /**
 813      * Returns the stacktraces from loading js modules.
 814      * @return array
 815      */
 816     public function get_loaded_modules() {
 817         return $this->debug_moduleloadstacktraces;
 818     }
 819
 820     /**
 821      * Ensure that the specified CSS file is linked to from this page.
 822      *
 823      * Because stylesheet links must go in the <head> part of the HTML, you must call
 824      * this function before {@link get_head_code()} is called. That normally means before
 825      * the call to print_header. If you call it when it is too late, an exception
 826      * will be thrown.
 827      *
 828      * Even if a particular style sheet is requested more than once, it will only
 829      * be linked to once.
 830      *
 831      * Please note use of this feature is strongly discouraged,
 832      * it is suitable only for places where CSS is submitted directly by teachers.
 833      * (Students must not be allowed to submit any external CSS because it may
 834      * contain embedded javascript!). Example of correct use is mod/data.
 835      *
 836      * @param string $stylesheet The path to the .css file, relative to $CFG->wwwroot.
 837      *   For example:
 838      *      $PAGE->requires->css('mod/data/css.php?d='.$data->id);
 839      */
 840     public function css($stylesheet) {
 841         global $CFG;
 842
 843         if ($this->headdone) {
 844             throw new coding_exception('Cannot require a CSS file after &lt;head> has been printed.', $stylesheet);
 845         }
 846
 847         if ($stylesheet instanceof moodle_url) {
 848             // ok
 849         } else if (strpos($stylesheet, '/') === 0) {
 850             $stylesheet = new moodle_url($CFG->httpswwwroot.$stylesheet);
 851         } else {
 852             throw new coding_exception('Invalid stylesheet parameter.', $stylesheet);
 853         }
 854
 855         $this->cssurls[$stylesheet->out()] = $stylesheet;
 856     }
 857
 858     /**
 859      * Add theme stylesheet to page - do not use from plugin code,
 860      * this should be called only from the core renderer!
 861      *
 862      * @param moodle_url $stylesheet
 863      * @return void
 864      */
 865     public function css_theme(moodle_url $stylesheet) {
 866         $this->cssthemeurls[] = $stylesheet;
 867     }
 868
 869     /**
 870      * Ensure that a skip link to a given target is printed at the top of the <body>.
 871      *
 872      * You must call this function before {@link get_top_of_body_code()}, (if not, an exception
 873      * will be thrown). That normally means you must call this before the call to print_header.
 874      *
 875      * If you ask for a particular skip link to be printed, it is then your responsibility
 876      * to ensure that the appropriate <a name="..."> tag is printed in the body of the
 877      * page, so that the skip link goes somewhere.
 878      *
 879      * Even if a particular skip link is requested more than once, only one copy of it will be output.
 880      *
 881      * @param string $target the name of anchor this link should go to. For example 'maincontent'.
 882      * @param string $linktext The text to use for the skip link. Normally get_string('skipto', 'access', ...);
 883      */
 884     public function skip_link_to($target, $linktext) {
 885         if ($this->topofbodydone) {
 886             debugging('Page header already printed, can not add skip links any more, code needs to be fixed.');
 887             return;
 888         }
 889         $this->skiplinks[$target] = $linktext;
 890     }
 891
 892     /**
 893      * !!!DEPRECATED!!! please use js_init_call() if possible
 894      * Ensure that the specified JavaScript function is called from an inline script
 895      * somewhere on this page.
 896      *
 897      * By default the call will be put in a script tag at the
 898      * end of the page after initialising Y instance, since this gives best page-load
 899      * performance and allows you to use YUI3 library.
 900      *
 901      * If you request that a particular function is called several times, then
 902      * that is what will happen (unlike linking to a CSS or JS file, where only
 903      * one link will be output).
 904      *
 905      * The main benefit of the method is the automatic encoding of all function parameters.
 906      *
 907      * @deprecated
 908      *
 909      * @param string $function the name of the JavaScritp function to call. Can
 910      *      be a compound name like 'Y.Event.purgeElement'. Can also be
 911      *      used to create and object by using a 'function name' like 'new user_selector'.
 912      * @param array $arguments and array of arguments to be passed to the function.
 913      *      When generating the function call, this will be escaped using json_encode,
 914      *      so passing objects and arrays should work.
 915      * @param bool $ondomready If tru the function is only called when the dom is
 916      *      ready for manipulation.
 917      * @param int $delay The delay before the function is called.
 918      */
 919     public function js_function_call($function, array $arguments = null, $ondomready = false, $delay = 0) {
 920         $where = $ondomready ? 'ondomready' : 'normal';
 921         $this->jscalls[$where][] = array($function, $arguments, $delay);
 922     }
 923
 924     /**
 925      * Adds a call to make use of a YUI gallery module. DEPRECATED DO NOT USE!!!
 926      *
 927      * @deprecated DO NOT USE
 928      *
 929      * @param string|array $modules One or more gallery modules to require
 930      * @param string $version
 931      * @param string $function
 932      * @param array $arguments
 933      * @param bool $ondomready
 934      */
 935     public function js_gallery_module($modules, $version, $function, array $arguments = null, $ondomready = false) {
 936         global $CFG;
 937         debugging('This function will be removed before 2.0 is released please change it from js_gallery_module to yui_module', DEBUG_DEVELOPER);
 938         $this->yui_module($modules, $function, $arguments, $version, $ondomready);
 939     }
 940
 941     /**
 942      * Creates a JavaScript function call that requires one or more modules to be loaded.
 943      *
 944      * This function can be used to include all of the standard YUI module types within JavaScript:
 945      *     - YUI3 modules    [node, event, io]
 946      *     - YUI2 modules    [yui2-*]
 947      *     - Moodle modules  [moodle-*]
 948      *     - Gallery modules [gallery-*]
 949      *
 950      * @param array|string $modules One or more modules
 951      * @param string $function The function to call once modules have been loaded
 952      * @param array $arguments An array of arguments to pass to the function
 953      * @param string $galleryversion The gallery version to use
 954      * @param bool $ondomready
 955      */
 956     public function yui_module($modules, $function, array $arguments = null, $galleryversion = null, $ondomready = false) {
 957         global $CFG;
 958
 959         if (!$galleryversion) {
 960             $galleryversion = '2010.04.08-12-35';
 961         }
 962
 963         if (!is_array($modules)) {
 964             $modules = array($modules);
 965         }
 966         if (empty($CFG->useexternalyui)) {
 967             // We need to set the M.yui.galleryversion to the correct version
 968             $jscode = 'M.yui.galleryversion='.json_encode($galleryversion).';';
 969         } else {
 970             // Set Y's config.gallery to the version
 971             $jscode = 'Y.config.gallery='.json_encode($galleryversion).';';
 972         }
 973         $jscode .= 'Y.use('.join(',', array_map('json_encode', convert_to_array($modules))).',function() {'.js_writer::function_call($function, $arguments).'});';
 974         if ($ondomready) {
 975             $jscode = "Y.on('domready', function() { $jscode });";
 976         }
 977         $this->jsinitcode[] = $jscode;
 978     }
 979
 980     /**
 981      * Ensure that the specified JavaScript function is called from an inline script
 982      * from page footer.
 983      *
 984      * @param string $function the name of the JavaScritp function to with init code,
 985      *      usually something like 'M.mod_mymodule.init'
 986      * @param array $extraarguments and array of arguments to be passed to the function.
 987      *      The first argument is always the YUI3 Y instance with all required dependencies
 988      *      already loaded.
 989      * @param bool $ondomready wait for dom ready (helps with some IE problems when modifying DOM)
 990      * @param array $module JS module specification array
 991      */
 992     public function js_init_call($function, array $extraarguments = null, $ondomready = false, array $module = null) {
 993         $jscode = js_writer::function_call_with_Y($function, $extraarguments);
 994         if (!$module) {
 995             // Detect module automatically.
 996             if (preg_match('/M\.([a-z0-9]+_[^\.]+)/', $function, $matches)) {
 997                 $module = $this->find_module($matches[1]);
 998             }
 999         }
1000
1001         $this->js_init_code($jscode, $ondomready, $module);
1002     }
1003
1004     /**
1005      * Add short static javascript code fragment to page footer.
1006      * This is intended primarily for loading of js modules and initialising page layout.
1007      * Ideally the JS code fragment should be stored in plugin renderer so that themes
1008      * may override it.
1009      *
1010      * @param string $jscode
1011      * @param bool $ondomready wait for dom ready (helps with some IE problems when modifying DOM)
1012      * @param array $module JS module specification array
1013      */
1014     public function js_init_code($jscode, $ondomready = false, array $module = null) {
1015         $jscode = trim($jscode, " ;\n"). ';';
1016
1017         if ($module) {
1018             $this->js_module($module);
1019             $modulename = $module['name'];
1020             $jscode = "Y.use('$modulename', function(Y) { $jscode });";
1021         }
1022
1023         if ($ondomready) {
1024             $jscode = "Y.on('domready', function() { $jscode });";
1025         }
1026
1027         $this->jsinitcode[] = $jscode;
1028     }
1029
1030     /**
1031      * Make a language string available to JavaScript.
1032      *
1033      * All the strings will be available in a M.str object in the global namespace.
1034      * So, for example, after a call to $PAGE->requires->string_for_js('course', 'moodle');
1035      * then the JavaScript variable M.str.moodle.course will be 'Course', or the
1036      * equivalent in the current language.
1037      *
1038      * The arguments to this function are just like the arguments to get_string
1039      * except that $component is not optional, and there are some aspects to consider
1040      * when the string contains {$a} placeholder.
1041      *
1042      * If the string does not contain any {$a} placeholder, you can simply use
1043      * M.str.component.identifier to obtain it. If you prefer, you can call
1044      * M.util.get_string(identifier, component) to get the same result.
1045      *
1046      * If you need to use {$a} placeholders, there are two options. Either the
1047      * placeholder should be substituted in PHP on server side or it should
1048      * be substituted in Javascript at client side.
1049      *
1050      * To substitute the placeholder at server side, just provide the required
1051      * value for the placeholder when you require the string. Because each string
1052      * is only stored once in the JavaScript (based on $identifier and $module)
1053      * you cannot get the same string with two different values of $a. If you try,
1054      * an exception will be thrown. Once the placeholder is substituted, you can
1055      * use M.str or M.util.get_string() as shown above:
1056      *
1057      *     // Require the string in PHP and replace the placeholder.
1058      *     $PAGE->requires->string_for_js('fullnamedisplay', 'moodle', $USER);
1059      *     // Use the result of the substitution in Javascript.
1060      *     alert(M.str.moodle.fullnamedisplay);
1061      *
1062      * To substitute the placeholder at client side, use M.util.get_string()
1063      * function. It implements the same logic as {@link get_string()}:
1064      *
1065      *     // Require the string in PHP but keep {$a} as it is.
1066      *     $PAGE->requires->string_for_js('fullnamedisplay', 'moodle');
1067      *     // Provide the values on the fly in Javascript.
1068      *     user = { firstname : 'Harry', lastname : 'Potter' }
1069      *     alert(M.util.get_string('fullnamedisplay', 'moodle', user);
1070      *
1071      * If you do need the same string expanded with different $a values in PHP
1072      * on server side, then the solution is to put them in your own data structure
1073      * (e.g. and array) that you pass to JavaScript with {@link data_for_js()}.
1074      *
1075      * @param string $identifier the desired string.
1076      * @param string $component the language file to look in.
1077      * @param mixed $a any extra data to add into the string (optional).
1078      */
1079     public function string_for_js($identifier, $component, $a = null) {
1080         if (!$component) {
1081             throw new coding_exception('The $component parameter is required for page_requirements_manager::string_for_js().');
1082         }
1083         if (isset($this->stringsforjs_as[$component][$identifier]) and $this->stringsforjs_as[$component][$identifier] !== $a) {
1084             throw new coding_exception("Attempt to re-define already required string '$identifier' " .
1085                     "from lang file '$component' with different \$a parameter?");
1086         }
1087         if (!isset($this->stringsforjs[$component][$identifier])) {
1088             $this->stringsforjs[$component][$identifier] = new lang_string($identifier, $component, $a);
1089             $this->stringsforjs_as[$component][$identifier] = $a;
1090         }
1091     }
1092
1093     /**
1094      * Make an array of language strings available for JS.
1095      *
1096      * This function calls the above function {@link string_for_js()} for each requested
1097      * string in the $identifiers array that is passed to the argument for a single module
1098      * passed in $module.
1099      *
1100      * <code>
1101      * $PAGE->requires->strings_for_js(array('one', 'two', 'three'), 'mymod', array('a', null, 3));
1102      *
1103      * // The above is identical to calling:
1104      *
1105      * $PAGE->requires->string_for_js('one', 'mymod', 'a');
1106      * $PAGE->requires->string_for_js('two', 'mymod');
1107      * $PAGE->requires->string_for_js('three', 'mymod', 3);
1108      * </code>
1109      *
1110      * @param array $identifiers An array of desired strings
1111      * @param string $component The module to load for
1112      * @param mixed $a This can either be a single variable that gets passed as extra
1113      *         information for every string or it can be an array of mixed data where the
1114      *         key for the data matches that of the identifier it is meant for.
1115      *
1116      */
1117     public function strings_for_js($identifiers, $component, $a = null) {
1118         foreach ($identifiers as $key => $identifier) {
1119             if (is_array($a) && array_key_exists($key, $a)) {
1120                 $extra = $a[$key];
1121             } else {
1122                 $extra = $a;
1123             }
1124             $this->string_for_js($identifier, $component, $extra);
1125         }
1126     }
1127
1128     /**
1129      * !!!!!!DEPRECATED!!!!!! please use js_init_call() for everything now.
1130      *
1131      * Make some data from PHP available to JavaScript code.
1132      *
1133      * For example, if you call
1134      * <pre>
1135      *      $PAGE->requires->data_for_js('mydata', array('name' => 'Moodle'));
1136      * </pre>
1137      * then in JavsScript mydata.name will be 'Moodle'.
1138      *
1139      * @deprecated
1140      * @param string $variable the the name of the JavaScript variable to assign the data to.
1141      *      Will probably work if you use a compound name like 'mybuttons.button[1]', but this
1142      *      should be considered an experimental feature.
1143      * @param mixed $data The data to pass to JavaScript. This will be escaped using json_encode,
1144      *      so passing objects and arrays should work.
1145      * @param bool $inhead initialise in head
1146      * @return void
1147      */
1148     public function data_for_js($variable, $data, $inhead=false) {
1149         $where = $inhead ? 'head' : 'footer';
1150         $this->jsinitvariables[$where][] = array($variable, $data);
1151     }
1152
1153     /**
1154      * Creates a YUI event handler.
1155      *
1156      * @param mixed $selector standard YUI selector for elements, may be array or string, element id is in the form "#idvalue"
1157      * @param string $event A valid DOM event (click, mousedown, change etc.)
1158      * @param string $function The name of the function to call
1159      * @param array  $arguments An optional array of argument parameters to pass to the function
1160      */
1161     public function event_handler($selector, $event, $function, array $arguments = null) {
1162         $this->eventhandlers[] = array('selector'=>$selector, 'event'=>$event, 'function'=>$function, 'arguments'=>$arguments);
1163     }
1164
1165     /**
1166      * Returns code needed for registering of event handlers.
1167      * @return string JS code
1168      */
1169     protected function get_event_handler_code() {
1170         $output = '';
1171         foreach ($this->eventhandlers as $h) {
1172             $output .= js_writer::event_handler($h['selector'], $h['event'], $h['function'], $h['arguments']);
1173         }
1174         return $output;
1175     }
1176
1177     /**
1178      * Get the inline JavaScript code that need to appear in a particular place.
1179      * @param bool $ondomready
1180      * @return string
1181      */
1182     protected function get_javascript_code($ondomready) {
1183         $where = $ondomready ? 'ondomready' : 'normal';
1184         $output = '';
1185         if ($this->jscalls[$where]) {
1186             foreach ($this->jscalls[$where] as $data) {
1187                 $output .= js_writer::function_call($data[0], $data[1], $data[2]);
1188             }
1189             if (!empty($ondomready)) {
1190                 $output = "    Y.on('domready', function() {\n$output\n    });";
1191             }
1192         }
1193         return $output;
1194     }
1195
1196     /**
1197      * Returns js code to be executed when Y is available.
1198      * @return string
1199      */
1200     protected function get_javascript_init_code() {
1201         if (count($this->jsinitcode)) {
1202             return implode("\n", $this->jsinitcode) . "\n";
1203         }
1204         return '';
1205     }
1206
1207     /**
1208      * Returns basic YUI3 JS loading code.
1209      * YUI3 is using autoloading of both CSS and JS code.
1210      *
1211      * Major benefit of this compared to standard js/csss loader is much improved
1212      * caching, better browser cache utilisation, much fewer http requests.
1213      *
1214      * @param moodle_page $page
1215      * @return string
1216      */
1217     protected function get_yui3lib_headcode($page) {
1218         global $CFG;
1219
1220         $code = '';
1221
1222         if ($this->yui3loader->combine) {
1223             if (!empty($page->theme->yuicssmodules)) {
1224                 $modules = array();
1225                 foreach ($page->theme->yuicssmodules as $module) {
1226                     $modules[] = "$CFG->yui3version/build/$module/$module-min.css";
1227                 }
1228                 $code .= '<link rel="stylesheet" type="text/css" href="'.$this->yui3loader->comboBase.implode('&amp;', $modules).'" />';
1229             }
1230             $code .= '<script type="text/javascript" src="'.$this->yui3loader->comboBase
1231                      .$CFG->yui3version.'/build/simpleyui/simpleyui-min.js&amp;'
1232                      .$CFG->yui3version.'/build/loader/loader-min.js"></script>';
1233         } else {
1234             if (!empty($page->theme->yuicssmodules)) {
1235                 foreach ($page->theme->yuicssmodules as $module) {
1236                     $code .= '<link rel="stylesheet" type="text/css" href="'.$this->yui3loader->base.$module.'/'.$module.'-min.css" />';
1237                 }
1238             }
1239             $code .= '<script type="text/javascript" src="'.$this->yui3loader->base.'simpleyui/simpleyui-min.js"></script>';
1240             $code .= '<script type="text/javascript" src="'.$this->yui3loader->base.'loader/loader-min.js"></script>';
1241         }
1242
1243
1244         if ($this->yui3loader->filter === 'RAW') {
1245             $code = str_replace('-min.css', '.css', $code);
1246             $code = str_replace('-min.js', '.js', $code);
1247         } else if ($this->yui3loader->filter === 'DEBUG') {
1248             $code = str_replace('-min.css', '.css', $code);
1249             $code = str_replace('-min.js', '-debug.js', $code);
1250         }
1251
1252         return $code;
1253     }
1254
1255     /**
1256      * Returns html tags needed for inclusion of theme CSS.
1257      *
1258      * @return string
1259      */
1260     protected function get_css_code() {
1261         // First of all the theme CSS, then any custom CSS
1262         // Please note custom CSS is strongly discouraged,
1263         // because it can not be overridden by themes!
1264         // It is suitable only for things like mod/data which accepts CSS from teachers.
1265         $attributes = array('rel'=>'stylesheet', 'type'=>'text/css');
1266
1267         // This line of code may look funny but it is currently required in order
1268         // to avoid MASSIVE display issues in Internet Explorer.
1269         // As of IE8 + YUI3.1.1 the reference stylesheet (firstthemesheet) gets
1270         // ignored whenever another resource is added until such time as a redraw
1271         // is forced, usually by moving the mouse over the affected element.
1272         $code = html_writer::tag('script', '/** Required in order to fix style inclusion problems in IE with YUI **/', array('id'=>'firstthemesheet', 'type'=>'text/css'));
1273
1274         $urls = $this->cssthemeurls + $this->cssurls;
1275         foreach ($urls as $url) {
1276             $attributes['href'] = $url;
1277             $code .= html_writer::empty_tag('link', $attributes) . "\n";
1278             // This id is needed in first sheet only so that theme may override YUI sheets loaded on the fly.
1279             unset($attributes['id']);
1280         }
1281
1282         return $code;
1283     }
1284
1285     /**
1286      * Adds extra modules specified after printing of page header.
1287      *
1288      * @return string
1289      */
1290     protected function get_extra_modules_code() {
1291         if (empty($this->extramodules)) {
1292             return '';
1293         }
1294         return html_writer::script(js_writer::function_call('M.yui.add_module', array($this->extramodules)));
1295     }
1296
1297     /**
1298      * Generate any HTML that needs to go inside the <head> tag.
1299      *
1300      * Normally, this method is called automatically by the code that prints the
1301      * <head> tag. You should not normally need to call it in your own code.
1302      *
1303      * @param moodle_page $page
1304      * @param core_renderer $renderer
1305      * @return string the HTML code to to inside the <head> tag.
1306      */
1307     public function get_head_code(moodle_page $page, core_renderer $renderer) {
1308         global $CFG;
1309
1310         // Note: the $page and $output are not stored here because it would
1311         // create circular references in memory which prevents garbage collection.
1312         $this->init_requirements_data($page, $renderer);
1313
1314         $output = '';
1315
1316         // Set up the M namespace.
1317         $js = "var M = {}; M.yui = {};\n";
1318
1319         // Capture the time now ASAP during page load. This minimises the lag when
1320         // we try to relate times on the server to times in the browser.
1321         // An example of where this is used is the quiz countdown timer.
1322         $js .= "M.pageloadstarttime = new Date();\n";
1323
1324         // Add a subset of Moodle configuration to the M namespace.
1325         $js .= js_writer::set_variable('M.cfg', $this->M_cfg, false);
1326
1327         // Set up global YUI3 loader object - this should contain all code needed by plugins.
1328         // Note: in JavaScript just use "YUI().use('overlay', function(Y) { .... });",
1329         //       this needs to be done before including any other script.
1330         $js .= $this->YUI_config->get_config_functions();
1331         $js .= js_writer::set_variable('YUI_config', $this->YUI_config, false) . "\n";
1332         $js .= "M.yui.loader = {modules: {}};\n"; // Backwards compatibility only, not used any more.
1333         $js = $this->YUI_config->update_header_js($js);
1334
1335         $output .= html_writer::script($js);
1336
1337         // YUI3 JS and CSS need to be loaded in the header but after the YUI_config has been created.
1338         // They should be cached well by the browser.
1339         $output .= $this->get_yui3lib_headcode($page);
1340
1341         // Add hacked jQuery support, it is not intended for standard Moodle distribution!
1342         $output .= $this->get_jquery_headcode();
1343
1344         // Now theme CSS + custom CSS in this specific order.
1345         $output .= $this->get_css_code();
1346
1347         // Link our main JS file, all core stuff should be there.
1348         $output .= html_writer::script('', $this->js_fix_url('/lib/javascript-static.js'));
1349
1350         // Add variables.
1351         if ($this->jsinitvariables['head']) {
1352             $js = '';
1353             foreach ($this->jsinitvariables['head'] as $data) {
1354                 list($var, $value) = $data;
1355                 $js .= js_writer::set_variable($var, $value, true);
1356             }
1357             $output .= html_writer::script($js);
1358         }
1359
1360         // All the other linked things from HEAD - there should be as few as possible.
1361         if ($this->jsincludes['head']) {
1362             foreach ($this->jsincludes['head'] as $url) {
1363                 $output .= html_writer::script('', $url);
1364             }
1365         }
1366
1367         // Mark head sending done, it is not possible to anything there.
1368         $this->headdone = true;
1369
1370         return $output;
1371     }
1372
1373     /**
1374      * Generate any HTML that needs to go at the start of the <body> tag.
1375      *
1376      * Normally, this method is called automatically by the code that prints the
1377      * <head> tag. You should not normally need to call it in your own code.
1378      *
1379      * @return string the HTML code to go at the start of the <body> tag.
1380      */
1381     public function get_top_of_body_code() {
1382         // First the skip links.
1383         $links = '';
1384         $attributes = array('class'=>'skip');
1385         foreach ($this->skiplinks as $url => $text) {
1386             $attributes['href'] = '#' . $url;
1387             $links .= html_writer::tag('a', $text, $attributes);
1388         }
1389         $output = html_writer::tag('div', $links, array('class'=>'skiplinks')) . "\n";
1390
1391         // Then the clever trick for hiding of things not needed when JS works.
1392         $output .= html_writer::script("document.body.className += ' jsenabled';") . "\n";
1393         $this->topofbodydone = true;
1394         return $output;
1395     }
1396
1397     /**
1398      * Generate any HTML that needs to go at the end of the page.
1399      *
1400      * Normally, this method is called automatically by the code that prints the
1401      * page footer. You should not normally need to call it in your own code.
1402      *
1403      * @return string the HTML code to to at the end of the page.
1404      */
1405     public function get_end_code() {
1406         global $CFG;
1407
1408         // Add other requested modules.
1409         $output = $this->get_extra_modules_code();
1410
1411         // All the other linked scripts - there should be as few as possible.
1412         if ($this->jsincludes['footer']) {
1413             foreach ($this->jsincludes['footer'] as $url) {
1414                 $output .= html_writer::script('', $url);
1415             }
1416         }
1417
1418         // Add all needed strings.
1419         if (!empty($this->stringsforjs)) {
1420             $strings = array();
1421             foreach ($this->stringsforjs as $component=>$v) {
1422                 foreach($v as $indentifier => $langstring) {
1423                     $strings[$component][$indentifier] = $langstring->out();
1424                 }
1425             }
1426             $output .= html_writer::script(js_writer::set_variable('M.str', $strings));
1427         }
1428
1429         // Add variables.
1430         if ($this->jsinitvariables['footer']) {
1431             $js = '';
1432             foreach ($this->jsinitvariables['footer'] as $data) {
1433                 list($var, $value) = $data;
1434                 $js .= js_writer::set_variable($var, $value, true);
1435             }
1436             $output .= html_writer::script($js);
1437         }
1438
1439         $inyuijs = $this->get_javascript_code(false);
1440         $ondomreadyjs = $this->get_javascript_code(true);
1441         $jsinit = $this->get_javascript_init_code();
1442         $handlersjs = $this->get_event_handler_code();
1443
1444         // There is no global Y, make sure it is available in your scope.
1445         $js = "YUI().use('node', function(Y) {\n{$inyuijs}{$ondomreadyjs}{$jsinit}{$handlersjs}\n});";
1446
1447         $output .= html_writer::script($js);
1448
1449         return $output;
1450     }
1451
1452     /**
1453      * Have we already output the code in the <head> tag?
1454      *
1455      * @return bool
1456      */
1457     public function is_head_done() {
1458         return $this->headdone;
1459     }
1460
1461     /**
1462      * Have we already output the code at the start of the <body> tag?
1463      *
1464      * @return bool
1465      */
1466     public function is_top_of_body_done() {
1467         return $this->topofbodydone;
1468     }
1469 }
1470
1471 /**
1472  * This class represents the YUI configuration.
1473  *
1474  * @copyright 2013 Andrew Nicols
1475  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
1476  * @since Moodle 2.5
1477  * @package core
1478  * @category output
1479  */
1480 class YUI_config {
1481     /**
1482      * These settings must be public so that when the object is converted to json they are exposed.
1483      * Note: Some of these are camelCase because YUI uses camelCase variable names.
1484      *
1485      * The settings are described and documented in the YUI API at:
1486      * - http://yuilibrary.com/yui/docs/api/classes/config.html
1487      * - http://yuilibrary.com/yui/docs/api/classes/Loader.html
1488      */
1489     public $debug = false;
1490     public $base;
1491     public $comboBase;
1492     public $combine;
1493     public $filter = null;
1494     public $insertBefore = 'firstthemesheet';
1495     public $groups = array();
1496     public $modules = array();
1497
1498     /**
1499      * @var array List of functions used by the YUI Loader group pattern recognition.
1500      */
1501     protected $jsconfigfunctions = array();
1502
1503     /**
1504      * Create a new group within the YUI_config system.
1505      *
1506      * @param String $name The name of the group. This must be unique and
1507      * not previously used.
1508      * @param Array $config The configuration for this group.
1509      * @return void
1510      */
1511     public function add_group($name, $config) {
1512         if (isset($this->groups[$name])) {
1513             throw new coding_exception("A YUI configuration group for '{$name}' already exists. To make changes to this group use YUI_config->update_group().");
1514         }
1515         $this->groups[$name] = $config;
1516     }
1517
1518     /**
1519      * Update an existing group configuration
1520      *
1521      * Note, any existing configuration for that group will be wiped out.
1522      * This includes module configuration.
1523      *
1524      * @param String $name The name of the group. This must be unique and
1525      * not previously used.
1526      * @param Array $config The configuration for this group.
1527      * @return void
1528      */
1529     public function update_group($name, $config) {
1530         if (!isset($this->groups[$name])) {
1531             throw new coding_exception('The Moodle YUI module does not exist. You must define the moodle module config using YUI_config->add_module_config first.');
1532         }
1533         $this->groups[$name] = $config;
1534     }
1535
1536     /**
1537      * Set the value of a configuration function used by the YUI Loader's pattern testing.
1538      *
1539      * Only the body of the function should be passed, and not the whole function wrapper.
1540      *
1541      * The JS function your write will be passed a single argument 'name' containing the
1542      * name of the module being loaded.
1543      *
1544      * @param $function String the body of the JavaScript function. This should be used i
1545      * @return String the name of the function to use in the group pattern configuration.
1546      */
1547     public function set_config_function($function) {
1548         $configname = 'yui' . (count($this->jsconfigfunctions) + 1) . 'ConfigFn';
1549         if (isset($this->jsconfigfunctions[$configname])) {
1550             throw new coding_exception("A YUI config function with this name already exists. Config function names must be unique.");
1551         }
1552         $this->jsconfigfunctions[$configname] = $function;
1553         return '@' . $configname . '@';
1554     }
1555
1556     /**
1557      * Retrieve the list of JavaScript functions for YUI_config groups.
1558      *
1559      * @return String The complete set of config functions
1560      */
1561     public function get_config_functions() {
1562         $configfunctions = '';
1563         foreach ($this->jsconfigfunctions as $functionname => $function) {
1564             $configfunctions .= "var {$functionname} = function(me) {";
1565             $configfunctions .= $function;
1566             $configfunctions .= "};\n";
1567         }
1568         return $configfunctions;
1569     }
1570
1571     /**
1572      * Update the header JavaScript with any required modification for the YUI Loader.
1573      *
1574      * @param $js String The JavaScript to manipulate.
1575      * @return String the modified JS string.
1576      */
1577     public function update_header_js($js) {
1578         // Update the names of the the configFn variables.
1579         // The PHP json_encode function cannot handle literal names so we have to wrap
1580         // them in @ and then replace them with literals of the same function name.
1581         foreach ($this->jsconfigfunctions as $functionname => $function) {
1582             $js = str_replace('"@' . $functionname . '@"', $functionname, $js);
1583         }
1584         return $js;
1585     }
1586
1587     /**
1588      * Add configuration for a specific module.
1589      *
1590      * @param String $name The name of the module to add configuration for.
1591      * @param Array $config The configuration for the specified module.
1592      * @param String $group The name of the group to add configuration for.
1593      * If not specified, then this module is added to the global
1594      * configuration.
1595      * @return void
1596      */
1597     public function add_module_config($name, $config, $group = null) {
1598         if ($group) {
1599             if (!isset($this->groups[$name])) {
1600                 throw new coding_exception('The Moodle YUI module does not exist. You must define the moodle module config using YUI_config->add_module_config first.');
1601             }
1602             if (!isset($this->groups[$group]['modules'])) {
1603                 $this->groups[$group]['modules'] = array();
1604             }
1605             $modules = &$this->groups[$group]['modules'];
1606         } else {
1607             $modules = &$this->modules;
1608         }
1609         $modules[$name] = $config;
1610     }
1611
1612     /**
1613      * Add the moodle YUI module metadata for the moodle group to the YUI_config instance.
1614      *
1615      * If js caching is disabled, metadata will not be served causing YUI to calculate
1616      * module dependencies as each module is loaded.
1617      *
1618      * If metadata does not exist it will be created and stored in a MUC entry.
1619      *
1620      * @return void
1621      */
1622     public function add_moodle_metadata() {
1623         global $CFG;
1624         if (!isset($this->groups['moodle'])) {
1625             throw new coding_exception('The Moodle YUI module does not exist. You must define the moodle module config using YUI_config->add_module_config first.');
1626         }
1627
1628         if (!isset($this->groups['moodle']['modules'])) {
1629             $this->groups['moodle']['modules'] = array();
1630         }
1631
1632         $cache = cache::make('core', 'yuimodules');
1633         if (!isset($CFG->jsrev) || $CFG->jsrev == -1) {
1634             $metadata = array();
1635             $cache->delete('metadata');
1636         } else {
1637             // Attempt to get the metadata from the cache.
1638             if (!$metadata = $cache->get('metadata')) {
1639                 $metadata = $this->get_moodle_metadata();
1640                 $cache->set('metadata', $metadata);
1641             }
1642         }
1643
1644         // Merge with any metadata added specific to this page which was added manually.
1645         $this->groups['moodle']['modules'] = array_merge($this->groups['moodle']['modules'],
1646                 $metadata);
1647     }
1648
1649     /**
1650      * Determine the module metadata for all moodle YUI modules.
1651      *
1652      * This works through all modules capable of serving YUI modules, and attempts to get
1653      * metadata for each of those modules.
1654      *
1655      * @return Array of module metadata
1656      */
1657     private function get_moodle_metadata() {
1658         $moodlemodules = array();
1659         // Core isn't a plugin type or subsystem - handle it seperately.
1660         if ($module = $this->get_moodle_path_metadata(get_component_directory('core'))) {
1661             $moodlemodules = array_merge($moodlemodules, $module);
1662         }
1663
1664         // Handle other core subsystems.
1665         $subsystems = get_core_subsystems();
1666         foreach ($subsystems as $subsystem => $path) {
1667             if (is_null($path)) {
1668                 continue;
1669             }
1670             $path = get_component_directory($subsystem);
1671             if ($module = $this->get_moodle_path_metadata($path)) {
1672                 $moodlemodules = array_merge($moodlemodules, $module);
1673             }
1674         }
1675
1676         // And finally the plugins.
1677         $plugintypes = get_plugin_types();
1678         foreach ($plugintypes as $plugintype => $pathroot) {
1679             $pluginlist = get_plugin_list($plugintype);
1680             foreach ($pluginlist as $plugin => $path) {
1681                 if ($module = $this->get_moodle_path_metadata($path)) {
1682                     $moodlemodules = array_merge($moodlemodules, $module);
1683                 }
1684             }
1685         }
1686
1687         return $moodlemodules;
1688     }
1689
1690     /**
1691      * Helper function process and return the YUI metadata for all of the modules under the specified path.
1692      *
1693      * @param String $path the UNC path to the YUI src directory.
1694      * @return Array the complete array for frankenstyle directory.
1695      */
1696     private function get_moodle_path_metadata($path) {
1697         // Add module metadata is stored in frankenstyle_modname/yui/src/yui_modname/meta/yui_modname.json.
1698         $baseyui = $path . '/yui/src';
1699         $modules = array();
1700         if (is_dir($baseyui)) {
1701             $items = new DirectoryIterator($baseyui);
1702             foreach ($items as $item) {
1703                 if ($item->isDot() or !$item->isDir()) {
1704                     continue;
1705                 }
1706                 $metafile = realpath($baseyui . '/' . $item . '/meta/' . $item . '.json');
1707                 if (!is_readable($metafile)) {
1708                     continue;
1709                 }
1710                 $metadata = file_get_contents($metafile);
1711                 $modules = array_merge($modules, (array) json_decode($metadata));
1712             }
1713         }
1714         return $modules;
1715     }
1716 }
1717
1718 /**
1719  * Invalidate all server and client side JS caches.
1720  */
1721 function js_reset_all_caches() {
1722     global $CFG;
1723     require_once("$CFG->libdir/filelib.php");
1724
1725     $next = time();
1726     if (isset($CFG->jsrev) and $next <= $CFG->jsrev and $CFG->jsrev - $next < 60*60) {
1727         // This resolves problems when reset is requested repeatedly within 1s,
1728         // the < 1h condition prevents accidental switching to future dates
1729         // because we might not recover from it.
1730         $next = $CFG->jsrev+1;
1731     }
1732
1733     set_config('jsrev', $next);
1734     fulldelete("$CFG->cachedir/js");
1735 }