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   1  // This file is part of Moodle - http://moodle.org/
   2  //
   3  // Moodle is free software: you can redistribute it and/or modify
   4  // it under the terms of the GNU General Public License as published by
   5  // the Free Software Foundation, either version 3 of the License, or
   6  // (at your option) any later version.
   7  //
   8  // Moodle is distributed in the hope that it will be useful,
   9  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  // GNU General Public License for more details.
  12  //
  13  // You should have received a copy of the GNU General Public License
  14  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  15  
  16  /**
  17   * Javascript library for enableing a drag and drop upload to courses
  18   *
  19   * @package    core
  20   * @subpackage course
  21   * @copyright  2012 Davo Smith
  22   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23   */
  24  M.course_dndupload = {
  25      // YUI object.
  26      Y: null,
  27      // URL for upload requests
  28      url: M.cfg.wwwroot + '/course/dndupload.php',
  29      // maximum size of files allowed in this form
  30      maxbytes: 0,
  31      // ID of the course we are on
  32      courseid: null,
  33      // Data about the different file/data handlers that are available
  34      handlers: null,
  35      // Nasty hack to distinguish between dragenter(first entry),
  36      // dragenter+dragleave(moving between child elements) and dragleave (leaving element)
  37      entercount: 0,
  38      // Used to keep track of the section we are dragging across - to make
  39      // spotting movement between sections more reliable
  40      currentsection: null,
  41      // Used to store the pending uploads whilst the user is being asked for further input
  42      uploadqueue: null,
  43      // True if the there is currently a dialog being shown (asking for a name, or giving a
  44      // choice of file handlers)
  45      uploaddialog: false,
  46      // An array containing the last selected file handler for each file type
  47      lastselected: null,
  48  
  49      // The following are used to identify specific parts of the course page
  50  
  51      // The type of HTML element that is a course section
  52      sectiontypename: 'li',
  53      // The classes that an element must have to be identified as a course section
  54      sectionclasses: ['section', 'main'],
  55      // The ID of the main content area of the page (for adding the 'status' div)
  56      pagecontentid: 'page',
  57      // The selector identifying the list of modules within a section (note changing this may require
  58      // changes to the get_mods_element function)
  59      modslistselector: 'ul.section',
  60  
  61      /**
  62       * Initalise the drag and drop upload interface
  63       * Note: one and only one of options.filemanager and options.formcallback must be defined
  64       *
  65       * @param Y the YUI object
  66       * @param object options {
  67       *            courseid: ID of the course we are on
  68       *            maxbytes: maximum size of files allowed in this form
  69       *            handlers: Data about the different file/data handlers that are available
  70       *          }
  71       */
  72      init: function(Y, options) {
  73          this.Y = Y;
  74  
  75          if (!this.browser_supported()) {
  76              return; // Browser does not support the required functionality
  77          }
  78  
  79          this.maxbytes = options.maxbytes;
  80          this.courseid = options.courseid;
  81          this.handlers = options.handlers;
  82          this.uploadqueue = new Array();
  83          this.lastselected = new Array();
  84  
  85          var sectionselector = this.sectiontypename + '.' + this.sectionclasses.join('.');
  86          var sections = this.Y.all(sectionselector);
  87          if (sections.isEmpty()) {
  88              return; // No sections - incompatible course format or front page.
  89          }
  90          sections.each( function(el) {
  91              this.add_preview_element(el);
  92              this.init_events(el);
  93          }, this);
  94  
  95          if (options.showstatus) {
  96              this.add_status_div();
  97          }
  98      },
  99  
 100      /**
 101       * Add a div element to tell the user that drag and drop upload
 102       * is available (or to explain why it is not available)
 103       */
 104      add_status_div: function() {
 105          var Y = this.Y,
 106              coursecontents = Y.one('#' + this.pagecontentid),
 107              div,
 108              handlefile = (this.handlers.filehandlers.length > 0),
 109              handletext = false,
 110              handlelink = false,
 111              i = 0,
 112              styletop,
 113              styletopunit;
 114  
 115          if (!coursecontents) {
 116              return;
 117          }
 118  
 119          div = Y.Node.create('<div id="dndupload-status"></div>').setStyle('opacity', '0.0');
 120          coursecontents.insert(div, 0);
 121  
 122          for (i = 0; i < this.handlers.types.length; i++) {
 123              switch (this.handlers.types[i].identifier) {
 124                  case 'text':
 125                  case 'text/html':
 126                      handletext = true;
 127                      break;
 128                  case 'url':
 129                      handlelink = true;
 130                      break;
 131              }
 132          }
 133          $msgident = 'dndworking';
 134          if (handlefile) {
 135              $msgident += 'file';
 136          }
 137          if (handletext) {
 138              $msgident += 'text';
 139          }
 140          if (handlelink) {
 141              $msgident += 'link';
 142          }
 143          div.setContent(M.util.get_string($msgident, 'moodle'));
 144  
 145          styletop = div.getStyle('top') || '0px';
 146          styletopunit = styletop.replace(/^\d+/, '');
 147          styletop = parseInt(styletop.replace(/\D*$/, ''), 10);
 148  
 149          var fadein = new Y.Anim({
 150              node: '#dndupload-status',
 151              from: {
 152                  opacity: 0.0,
 153                  top: (styletop - 30).toString() + styletopunit
 154              },
 155  
 156              to: {
 157                  opacity: 1.0,
 158                  top: styletop.toString() + styletopunit
 159              },
 160              duration: 0.5
 161          });
 162  
 163          var fadeout = new Y.Anim({
 164              node: '#dndupload-status',
 165              from: {
 166                  opacity: 1.0,
 167                  top: styletop.toString() + styletopunit
 168              },
 169  
 170              to: {
 171                  opacity: 0.0,
 172                  top: (styletop - 30).toString() + styletopunit
 173              },
 174              duration: 0.5
 175          });
 176  
 177          fadein.run();
 178          fadein.on('end', function(e) {
 179              Y.later(3000, this, function() {
 180                  fadeout.run();
 181              });
 182          });
 183  
 184          fadeout.on('end', function(e) {
 185              Y.one('#dndupload-status').remove(true);
 186          });
 187      },
 188  
 189      /**
 190       * Check the browser has the required functionality
 191       * @return true if browser supports drag/drop upload
 192       */
 193      browser_supported: function() {
 194          if (typeof FileReader == 'undefined') {
 195              return false;
 196          }
 197          if (typeof FormData == 'undefined') {
 198              return false;
 199          }
 200          return true;
 201      },
 202  
 203      /**
 204       * Initialise drag events on node container, all events need
 205       * to be processed for drag and drop to work
 206       * @param el the element to add events to
 207       */
 208      init_events: function(el) {
 209          this.Y.on('dragenter', this.drag_enter, el, this);
 210          this.Y.on('dragleave', this.drag_leave, el, this);
 211          this.Y.on('dragover',  this.drag_over,  el, this);
 212          this.Y.on('drop',      this.drop,       el, this);
 213      },
 214  
 215      /**
 216       * Work out which course section a given element is in
 217       * @param el the child DOM element within the section
 218       * @return the DOM element representing the section
 219       */
 220      get_section: function(el) {
 221          var sectionclasses = this.sectionclasses;
 222          return el.ancestor( function(test) {
 223              var i;
 224              for (i=0; i<sectionclasses.length; i++) {
 225                  if (!test.hasClass(sectionclasses[i])) {
 226                      return false;
 227                  }
 228                  return true;
 229              }
 230          }, true);
 231      },
 232  
 233      /**
 234       * Work out the number of the section we have been dropped on to, from the section element
 235       * @param DOMElement section the selected section
 236       * @return int the section number
 237       */
 238      get_section_number: function(section) {
 239          var sectionid = section.get('id').split('-');
 240          if (sectionid.length < 2 || sectionid[0] != 'section') {
 241              return false;
 242          }
 243          return parseInt(sectionid[1]);
 244      },
 245  
 246      /**
 247       * Check if the event includes data of the given type
 248       * @param e the event details
 249       * @param type the data type to check for
 250       * @return true if the data type is found in the event data
 251       */
 252      types_includes: function(e, type) {
 253          var i;
 254          var types = e._event.dataTransfer.types;
 255          type = type.toLowerCase();
 256          for (i=0; i<types.length; i++) {
 257              if (!types.hasOwnProperty(i)) {
 258                  continue;
 259              }
 260              if (types[i].toLowerCase() === type) {
 261                  return true;
 262              }
 263          }
 264          return false;
 265      },
 266  
 267      /**
 268       * Look through the event data, checking it against the registered data types
 269       * (in order of priority) and return details of the first matching data type
 270       * @param e the event details
 271       * @return object|false - false if not found or an object {
 272       *           realtype: the type as given by the browser
 273       *           addmessage: the message to show to the user during dragging
 274       *           namemessage: the message for requesting a name for the resource from the user
 275       *           type: the identifier of the type (may match several 'realtype's)
 276       *           }
 277       */
 278      drag_type: function(e) {
 279          // Check there is some data attached.
 280          if (e._event.dataTransfer === null) {
 281              return false;
 282          }
 283          if (e._event.dataTransfer.types === null) {
 284              return false;
 285          }
 286          if (e._event.dataTransfer.types.length == 0) {
 287              return false;
 288          }
 289  
 290          // Check for files first.
 291          if (this.types_includes(e, 'Files')) {
 292              if (e.type != 'drop' || e._event.dataTransfer.files.length != 0) {
 293                  if (this.handlers.filehandlers.length == 0) {
 294                      return false; // No available file handlers - ignore this drag.
 295                  }
 296                  return {
 297                      realtype: 'Files',
 298                      addmessage: M.util.get_string('addfilehere', 'moodle'),
 299                      namemessage: null, // Should not be asked for anyway
 300                      type: 'Files'
 301                  };
 302              }
 303          }
 304  
 305          // Check each of the registered types.
 306          var types = this.handlers.types;
 307          for (var i=0; i<types.length; i++) {
 308              // Check each of the different identifiers for this type
 309              var dttypes = types[i].datatransfertypes;
 310              for (var j=0; j<dttypes.length; j++) {
 311                  if (this.types_includes(e, dttypes[j])) {
 312                      return {
 313                          realtype: dttypes[j],
 314                          addmessage: types[i].addmessage,
 315                          namemessage: types[i].namemessage,
 316                          handlermessage: types[i].handlermessage,
 317                          type: types[i].identifier,
 318                          handlers: types[i].handlers
 319                      };
 320                  }
 321              }
 322          }
 323          return false; // No types we can handle
 324      },
 325  
 326      /**
 327       * Check the content of the drag/drop includes a type we can handle, then, if
 328       * it is, notify the browser that we want to handle it
 329       * @param event e
 330       * @return string type of the event or false
 331       */
 332      check_drag: function(e) {
 333          var type = this.drag_type(e);
 334          if (type) {
 335              // Notify browser that we will handle this drag/drop
 336              e.stopPropagation();
 337              e.preventDefault();
 338          }
 339          return type;
 340      },
 341  
 342      /**
 343       * Handle a dragenter event: add a suitable 'add here' message
 344       * when a drag event occurs, containing a registered data type
 345       * @param e event data
 346       * @return false to prevent the event from continuing to be processed
 347       */
 348      drag_enter: function(e) {
 349          if (!(type = this.check_drag(e))) {
 350              return false;
 351          }
 352  
 353          var section = this.get_section(e.currentTarget);
 354          if (!section) {
 355              return false;
 356          }
 357  
 358          if (this.currentsection && this.currentsection != section) {
 359              this.currentsection = section;
 360              this.entercount = 1;
 361          } else {
 362              this.entercount++;
 363              if (this.entercount > 2) {
 364                  this.entercount = 2;
 365                  return false;
 366              }
 367          }
 368  
 369          this.show_preview_element(section, type);
 370  
 371          return false;
 372      },
 373  
 374      /**
 375       * Handle a dragleave event: remove the 'add here' message (if present)
 376       * @param e event data
 377       * @return false to prevent the event from continuing to be processed
 378       */
 379      drag_leave: function(e) {
 380          if (!this.check_drag(e)) {
 381              return false;
 382          }
 383  
 384          this.entercount--;
 385          if (this.entercount == 1) {
 386              return false;
 387          }
 388          this.entercount = 0;
 389          this.currentsection = null;
 390  
 391          this.hide_preview_element();
 392          return false;
 393      },
 394  
 395      /**
 396       * Handle a dragover event: just prevent the browser default (necessary
 397       * to allow drag and drop handling to work)
 398       * @param e event data
 399       * @return false to prevent the event from continuing to be processed
 400       */
 401      drag_over: function(e) {
 402          this.check_drag(e);
 403          return false;
 404      },
 405  
 406      /**
 407       * Handle a drop event: hide the 'add here' message, check the attached
 408       * data type and start the upload process
 409       * @param e event data
 410       * @return false to prevent the event from continuing to be processed
 411       */
 412      drop: function(e) {
 413          if (!(type = this.check_drag(e))) {
 414              return false;
 415          }
 416  
 417          this.hide_preview_element();
 418  
 419          // Work out the number of the section we are on (from its id)
 420          var section = this.get_section(e.currentTarget);
 421          var sectionnumber = this.get_section_number(section);
 422  
 423          // Process the file or the included data
 424          if (type.type == 'Files') {
 425              var files = e._event.dataTransfer.files;
 426              for (var i=0, f; f=files[i]; i++) {
 427                  this.handle_file(f, section, sectionnumber);
 428              }
 429          } else {
 430              var contents = e._event.dataTransfer.getData(type.realtype);
 431              if (contents) {
 432                  this.handle_item(type, contents, section, sectionnumber);
 433              }
 434          }
 435  
 436          return false;
 437      },
 438  
 439      /**
 440       * Find or create the 'ul' element that contains all of the module
 441       * instances in this section
 442       * @param section the DOM element representing the section
 443       * @return false to prevent the event from continuing to be processed
 444       */
 445      get_mods_element: function(section) {
 446          // Find the 'ul' containing the list of mods
 447          var modsel = section.one(this.modslistselector);
 448          if (!modsel) {
 449              // Create the above 'ul' if it doesn't exist
 450              modsel = document.createElement('ul');
 451              modsel.className = 'section img-text';
 452              var contentel = section.get('children').pop();
 453              var brel = contentel.get('children').pop();
 454              contentel.insertBefore(modsel, brel);
 455              modsel = this.Y.one(modsel);
 456          }
 457  
 458          return modsel;
 459      },
 460  
 461      /**
 462       * Add a new dummy item to the list of mods, to be replaced by a real
 463       * item & link once the AJAX upload call has completed
 464       * @param name the label to show in the element
 465       * @param section the DOM element reperesenting the course section
 466       * @return DOM element containing the new item
 467       */
 468      add_resource_element: function(name, section, module) {
 469          var modsel = this.get_mods_element(section);
 470  
 471          var resel = {
 472              parent: modsel,
 473              li: document.createElement('li'),
 474              div: document.createElement('div'),
 475              indentdiv: document.createElement('div'),
 476              a: document.createElement('a'),
 477              icon: document.createElement('img'),
 478              namespan: document.createElement('span'),
 479              groupingspan: document.createElement('span'),
 480              progressouter: document.createElement('span'),
 481              progress: document.createElement('span')
 482          };
 483  
 484          resel.li.className = 'activity ' + module + ' modtype_' + module;
 485  
 486          resel.indentdiv.className = 'mod-indent';
 487          resel.li.appendChild(resel.indentdiv);
 488  
 489          resel.div.className = 'activityinstance';
 490          resel.indentdiv.appendChild(resel.div);
 491  
 492          resel.a.href = '#';
 493          resel.div.appendChild(resel.a);
 494  
 495          resel.icon.src = M.util.image_url('i/ajaxloader');
 496          resel.icon.className = 'activityicon iconlarge';
 497          resel.a.appendChild(resel.icon);
 498  
 499          resel.namespan.className = 'instancename';
 500          resel.namespan.innerHTML = name;
 501          resel.a.appendChild(resel.namespan);
 502  
 503          resel.groupingspan.className = 'groupinglabel';
 504          resel.div.appendChild(resel.groupingspan);
 505  
 506          resel.progressouter.className = 'dndupload-progress-outer';
 507          resel.progress.className = 'dndupload-progress-inner';
 508          resel.progress.innerHTML = '&nbsp;';
 509          resel.progressouter.appendChild(resel.progress);
 510          resel.div.appendChild(resel.progressouter);
 511  
 512          modsel.insertBefore(resel.li, modsel.get('children').pop()); // Leave the 'preview element' at the bottom
 513  
 514          return resel;
 515      },
 516  
 517      /**
 518       * Hide any visible dndupload-preview elements on the page
 519       */
 520      hide_preview_element: function() {
 521          this.Y.all('li.dndupload-preview').addClass('dndupload-hidden');
 522          this.Y.all('.dndupload-over').removeClass('dndupload-over');
 523      },
 524  
 525      /**
 526       * Unhide the preview element for the given section and set it to display
 527       * the correct message
 528       * @param section the YUI node representing the selected course section
 529       * @param type the details of the data type detected in the drag (including the message to display)
 530       */
 531      show_preview_element: function(section, type) {
 532          this.hide_preview_element();
 533          var preview = section.one('li.dndupload-preview').removeClass('dndupload-hidden');
 534          section.addClass('dndupload-over');
 535  
 536          // Horrible work-around to allow the 'Add X here' text to be a drop target in Firefox.
 537          var node = preview.one('span').getDOMNode();
 538          node.firstChild.nodeValue = type.addmessage;
 539      },
 540  
 541      /**
 542       * Add the preview element to a course section. Note: this needs to be done before 'addEventListener'
 543       * is called, otherwise Firefox will ignore events generated when the mouse is over the preview
 544       * element (instead of passing them up to the parent element)
 545       * @param section the YUI node representing the selected course section
 546       */
 547      add_preview_element: function(section) {
 548          var modsel = this.get_mods_element(section);
 549          var preview = {
 550              li: document.createElement('li'),
 551              div: document.createElement('div'),
 552              icon: document.createElement('img'),
 553              namespan: document.createElement('span')
 554          };
 555  
 556          preview.li.className = 'dndupload-preview dndupload-hidden';
 557  
 558          preview.div.className = 'mod-indent';
 559          preview.li.appendChild(preview.div);
 560  
 561          preview.icon.src = M.util.image_url('t/addfile');
 562          preview.icon.className = 'icon';
 563          preview.div.appendChild(preview.icon);
 564  
 565          preview.div.appendChild(document.createTextNode(' '));
 566  
 567          preview.namespan.className = 'instancename';
 568          preview.namespan.innerHTML = M.util.get_string('addfilehere', 'moodle');
 569          preview.div.appendChild(preview.namespan);
 570  
 571          modsel.appendChild(preview.li);
 572      },
 573  
 574      /**
 575       * Find the registered handler for the given file type. If there is more than one, ask the
 576       * user which one to use. Then upload the file to the server
 577       * @param file the details of the file, taken from the FileList in the drop event
 578       * @param section the DOM element representing the selected course section
 579       * @param sectionnumber the number of the selected course section
 580       */
 581      handle_file: function(file, section, sectionnumber) {
 582          var handlers = new Array();
 583          var filehandlers = this.handlers.filehandlers;
 584          var extension = '';
 585          var dotpos = file.name.lastIndexOf('.');
 586          if (dotpos != -1) {
 587              extension = file.name.substr(dotpos+1, file.name.length).toLowerCase();
 588          }
 589  
 590          for (var i=0; i<filehandlers.length; i++) {
 591              if (filehandlers[i].extension == '*' || filehandlers[i].extension == extension) {
 592                  handlers.push(filehandlers[i]);
 593              }
 594          }
 595  
 596          if (handlers.length == 0) {
 597              // No handlers at all (not even 'resource'?)
 598              return;
 599          }
 600  
 601          if (handlers.length == 1) {
 602              this.upload_file(file, section, sectionnumber, handlers[0].module);
 603              return;
 604          }
 605  
 606          this.file_handler_dialog(handlers, extension, file, section, sectionnumber);
 607      },
 608  
 609      /**
 610       * Show a dialog box, allowing the user to choose what to do with the file they are uploading
 611       * @param handlers the available handlers to choose between
 612       * @param extension the extension of the file being uploaded
 613       * @param file the File object being uploaded
 614       * @param section the DOM element of the section being uploaded to
 615       * @param sectionnumber the number of the selected course section
 616       */
 617      file_handler_dialog: function(handlers, extension, file, section, sectionnumber) {
 618          if (this.uploaddialog) {
 619              var details = new Object();
 620              details.isfile = true;
 621              details.handlers = handlers;
 622              details.extension = extension;
 623              details.file = file;
 624              details.section = section;
 625              details.sectionnumber = sectionnumber;
 626              this.uploadqueue.push(details);
 627              return;
 628          }
 629          this.uploaddialog = true;
 630  
 631          var timestamp = new Date().getTime();
 632          var uploadid = Math.round(Math.random()*100000)+'-'+timestamp;
 633          var content = '';
 634          var sel;
 635          if (extension in this.lastselected) {
 636              sel = this.lastselected[extension];
 637          } else {
 638              sel = handlers[0].module;
 639          }
 640          content += '<p>'+M.util.get_string('actionchoice', 'moodle', file.name)+'</p>';
 641          content += '<div id="dndupload_handlers'+uploadid+'">';
 642          for (var i=0; i<handlers.length; i++) {
 643              var id = 'dndupload_handler'+uploadid+handlers[i].module;
 644              var checked = (handlers[i].module == sel) ? 'checked="checked" ' : '';
 645              content += '<input type="radio" name="handler" value="'+handlers[i].module+'" id="'+id+'" '+checked+'/>';
 646              content += ' <label for="'+id+'">';
 647              content += handlers[i].message;
 648              content += '</label><br/>';
 649          }
 650          content += '</div>';
 651  
 652          var Y = this.Y;
 653          var self = this;
 654          var panel = new M.core.dialogue({
 655              bodyContent: content,
 656              width: '350px',
 657              modal: true,
 658              visible: false,
 659              render: true,
 660              align: {
 661                  node: null,
 662                  points: [Y.WidgetPositionAlign.CC, Y.WidgetPositionAlign.CC]
 663              }
 664          });
 665          panel.show();
 666          // When the panel is hidden - destroy it and then check for other pending uploads
 667          panel.after("visibleChange", function(e) {
 668              if (!panel.get('visible')) {
 669                  panel.destroy(true);
 670                  self.check_upload_queue();
 671              }
 672          });
 673  
 674          // Add the submit/cancel buttons to the bottom of the dialog.
 675          panel.addButton({
 676              label: M.util.get_string('upload', 'moodle'),
 677              action: function(e) {
 678                  e.preventDefault();
 679                  // Find out which module was selected
 680                  var module = false;
 681                  var div = Y.one('#dndupload_handlers'+uploadid);
 682                  div.all('input').each(function(input) {
 683                      if (input.get('checked')) {
 684                          module = input.get('value');
 685                      }
 686                  });
 687                  if (!module) {
 688                      return;
 689                  }
 690                  panel.hide();
 691                  // Remember this selection for next time
 692                  self.lastselected[extension] = module;
 693                  // Do the upload
 694                  self.upload_file(file, section, sectionnumber, module);
 695              },
 696              section: Y.WidgetStdMod.FOOTER
 697          });
 698          panel.addButton({
 699              label: M.util.get_string('cancel', 'moodle'),
 700              action: function(e) {
 701                  e.preventDefault();
 702                  panel.hide();
 703              },
 704              section: Y.WidgetStdMod.FOOTER
 705          });
 706      },
 707  
 708      /**
 709       * Check to see if there are any other dialog boxes to show, now that the current one has
 710       * been dealt with
 711       */
 712      check_upload_queue: function() {
 713          this.uploaddialog = false;
 714          if (this.uploadqueue.length == 0) {
 715              return;
 716          }
 717  
 718          var details = this.uploadqueue.shift();
 719          if (details.isfile) {
 720              this.file_handler_dialog(details.handlers, details.extension, details.file, details.section, details.sectionnumber);
 721          } else {
 722              this.handle_item(details.type, details.contents, details.section, details.sectionnumber);
 723          }
 724      },
 725  
 726      /**
 727       * Do the file upload: show the dummy element, use an AJAX call to send the data
 728       * to the server, update the progress bar for the file, then replace the dummy
 729       * element with the real information once the AJAX call completes
 730       * @param file the details of the file, taken from the FileList in the drop event
 731       * @param section the DOM element representing the selected course section
 732       * @param sectionnumber the number of the selected course section
 733       */
 734      upload_file: function(file, section, sectionnumber, module) {
 735  
 736          // This would be an ideal place to use the Y.io function
 737          // however, this does not support data encoded using the
 738          // FormData object, which is needed to transfer data from
 739          // the DataTransfer object into an XMLHTTPRequest
 740          // This can be converted when the YUI issue has been integrated:
 741          // http://yuilibrary.com/projects/yui3/ticket/2531274
 742          var xhr = new XMLHttpRequest();
 743          var self = this;
 744  
 745          if (file.size > this.maxbytes) {
 746              new M.core.alert({message: M.util.get_string('namedfiletoolarge', 'moodle', {filename: file.name})});
 747              return;
 748          }
 749  
 750          // Add the file to the display
 751          var resel = this.add_resource_element(file.name, section, module);
 752  
 753          // Update the progress bar as the file is uploaded
 754          xhr.upload.addEventListener('progress', function(e) {
 755              if (e.lengthComputable) {
 756                  var percentage = Math.round((e.loaded * 100) / e.total);
 757                  resel.progress.style.width = percentage + '%';
 758              }
 759          }, false);
 760  
 761          // Wait for the AJAX call to complete, then update the
 762          // dummy element with the returned details
 763          xhr.onreadystatechange = function() {
 764              if (xhr.readyState == 4) {
 765                  if (xhr.status == 200) {
 766                      var result = JSON.parse(xhr.responseText);
 767                      if (result) {
 768                          if (result.error == 0) {
 769                              // All OK - replace the dummy element.
 770                              resel.li.outerHTML = result.fullcontent;
 771                              if (self.Y.UA.gecko > 0) {
 772                                  // Fix a Firefox bug which makes sites with a '~' in their wwwroot
 773                                  // log the user out when clicking on the link (before refreshing the page).
 774                                  resel.li.outerHTML = unescape(resel.li.outerHTML);
 775                              }
 776                              self.add_editing(result.elementid);
 777                          } else {
 778                              // Error - remove the dummy element
 779                              resel.parent.removeChild(resel.li);
 780                              new M.core.alert({message: result.error});
 781                          }
 782                      }
 783                  } else {
 784                      new M.core.alert({message: M.util.get_string('servererror', 'moodle')});
 785                  }
 786              }
 787          };
 788  
 789          // Prepare the data to send
 790          var formData = new FormData();
 791          formData.append('repo_upload_file', file);
 792          formData.append('sesskey', M.cfg.sesskey);
 793          formData.append('course', this.courseid);
 794          formData.append('section', sectionnumber);
 795          formData.append('module', module);
 796          formData.append('type', 'Files');
 797  
 798          // Send the AJAX call
 799          xhr.open("POST", this.url, true);
 800          xhr.send(formData);
 801      },
 802  
 803      /**
 804       * Show a dialog box to gather the name of the resource / activity to be created
 805       * from the uploaded content
 806       * @param type the details of the type of content
 807       * @param contents the contents to be uploaded
 808       * @section the DOM element for the section being uploaded to
 809       * @sectionnumber the number of the section being uploaded to
 810       */
 811      handle_item: function(type, contents, section, sectionnumber) {
 812          if (type.handlers.length == 0) {
 813              // Nothing to handle this - should not have got here
 814              return;
 815          }
 816  
 817          if (type.handlers.length == 1 && type.handlers[0].noname) {
 818              // Only one handler and it doesn't need a name (i.e. a label).
 819              this.upload_item('', type.type, contents, section, sectionnumber, type.handlers[0].module);
 820              this.check_upload_queue();
 821              return;
 822          }
 823  
 824          if (this.uploaddialog) {
 825              var details = new Object();
 826              details.isfile = false;
 827              details.type = type;
 828              details.contents = contents;
 829              details.section = section;
 830              details.setcionnumber = sectionnumber;
 831              this.uploadqueue.push(details);
 832              return;
 833          }
 834          this.uploaddialog = true;
 835  
 836          var timestamp = new Date().getTime();
 837          var uploadid = Math.round(Math.random()*100000)+'-'+timestamp;
 838          var nameid = 'dndupload_handler_name'+uploadid;
 839          var content = '';
 840          if (type.handlers.length > 1) {
 841              content += '<p>'+type.handlermessage+'</p>';
 842              content += '<div id="dndupload_handlers'+uploadid+'">';
 843              var sel = type.handlers[0].module;
 844              for (var i=0; i<type.handlers.length; i++) {
 845                  var id = 'dndupload_handler'+uploadid+type.handlers[i].module;
 846                  var checked = (type.handlers[i].module == sel) ? 'checked="checked" ' : '';
 847                  content += '<input type="radio" name="handler" value="'+i+'" id="'+id+'" '+checked+'/>';
 848                  content += ' <label for="'+id+'">';
 849                  content += type.handlers[i].message;
 850                  content += '</label><br/>';
 851              }
 852              content += '</div>';
 853          }
 854          var disabled = (type.handlers[0].noname) ? ' disabled = "disabled" ' : '';
 855          content += '<label for="'+nameid+'">'+type.namemessage+'</label>';
 856          content += ' <input type="text" id="'+nameid+'" value="" '+disabled+' />';
 857  
 858          var Y = this.Y;
 859          var self = this;
 860          var panel = new M.core.dialogue({
 861              bodyContent: content,
 862              width: '350px',
 863              modal: true,
 864              visible: true,
 865              render: true,
 866              align: {
 867                  node: null,
 868                  points: [Y.WidgetPositionAlign.CC, Y.WidgetPositionAlign.CC]
 869              }
 870          });
 871  
 872          // When the panel is hidden - destroy it and then check for other pending uploads
 873          panel.after("visibleChange", function(e) {
 874              if (!panel.get('visible')) {
 875                  panel.destroy(true);
 876                  self.check_upload_queue();
 877              }
 878          });
 879  
 880          var namefield = Y.one('#'+nameid);
 881          var submit = function(e) {
 882              e.preventDefault();
 883              var name = Y.Lang.trim(namefield.get('value'));
 884              var module = false;
 885              var noname = false;
 886              if (type.handlers.length > 1) {
 887                  // Find out which module was selected
 888                  var div = Y.one('#dndupload_handlers'+uploadid);
 889                  div.all('input').each(function(input) {
 890                      if (input.get('checked')) {
 891                          var idx = input.get('value');
 892                          module = type.handlers[idx].module;
 893                          noname = type.handlers[idx].noname;
 894                      }
 895                  });
 896                  if (!module) {
 897                      return;
 898                  }
 899              } else {
 900                  module = type.handlers[0].module;
 901                  noname = type.handlers[0].noname;
 902              }
 903              if (name == '' && !noname) {
 904                  return;
 905              }
 906              if (noname) {
 907                  name = '';
 908              }
 909              panel.hide();
 910              // Do the upload
 911              self.upload_item(name, type.type, contents, section, sectionnumber, module);
 912          };
 913  
 914          // Add the submit/cancel buttons to the bottom of the dialog.
 915          panel.addButton({
 916              label: M.util.get_string('upload', 'moodle'),
 917              action: submit,
 918              section: Y.WidgetStdMod.FOOTER,
 919              name: 'submit'
 920          });
 921          panel.addButton({
 922              label: M.util.get_string('cancel', 'moodle'),
 923              action: function(e) {
 924                  e.preventDefault();
 925                  panel.hide();
 926              },
 927              section: Y.WidgetStdMod.FOOTER
 928          });
 929          var submitbutton = panel.getButton('submit').button;
 930          namefield.on('key', submit, 'enter'); // Submit the form if 'enter' pressed
 931          namefield.after('keyup', function() {
 932              if (Y.Lang.trim(namefield.get('value')) == '') {
 933                  submitbutton.disable();
 934              } else {
 935                  submitbutton.enable();
 936              }
 937          });
 938  
 939          // Enable / disable the 'name' box, depending on the handler selected.
 940          for (i=0; i<type.handlers.length; i++) {
 941              if (type.handlers[i].noname) {
 942                  Y.one('#dndupload_handler'+uploadid+type.handlers[i].module).on('click', function (e) {
 943                      namefield.set('disabled', 'disabled');
 944                      submitbutton.enable();
 945                  });
 946              } else {
 947                  Y.one('#dndupload_handler'+uploadid+type.handlers[i].module).on('click', function (e) {
 948                      namefield.removeAttribute('disabled');
 949                      namefield.focus();
 950                      if (Y.Lang.trim(namefield.get('value')) == '') {
 951                          submitbutton.disable();
 952                      }
 953                  });
 954              }
 955          }
 956  
 957          // Focus on the 'name' box
 958          Y.one('#'+nameid).focus();
 959      },
 960  
 961      /**
 962       * Upload any data types that are not files: display a dummy resource element, send
 963       * the data to the server, update the progress bar for the file, then replace the
 964       * dummy element with the real information once the AJAX call completes
 965       * @param name the display name for the resource / activity to create
 966       * @param type the details of the data type found in the drop event
 967       * @param contents the actual data that was dropped
 968       * @param section the DOM element representing the selected course section
 969       * @param sectionnumber the number of the selected course section
 970       * @param module the module chosen to handle this upload
 971       */
 972      upload_item: function(name, type, contents, section, sectionnumber, module) {
 973  
 974          // This would be an ideal place to use the Y.io function
 975          // however, this does not support data encoded using the
 976          // FormData object, which is needed to transfer data from
 977          // the DataTransfer object into an XMLHTTPRequest
 978          // This can be converted when the YUI issue has been integrated:
 979          // http://yuilibrary.com/projects/yui3/ticket/2531274
 980          var xhr = new XMLHttpRequest();
 981          var self = this;
 982  
 983          // Add the item to the display
 984          var resel = this.add_resource_element(name, section, module);
 985  
 986          // Wait for the AJAX call to complete, then update the
 987          // dummy element with the returned details
 988          xhr.onreadystatechange = function() {
 989              if (xhr.readyState == 4) {
 990                  if (xhr.status == 200) {
 991                      var result = JSON.parse(xhr.responseText);
 992                      if (result) {
 993                          if (result.error == 0) {
 994                              // All OK - replace the dummy element.
 995                              resel.li.outerHTML = result.fullcontent;
 996                              if (self.Y.UA.gecko > 0) {
 997                                  // Fix a Firefox bug which makes sites with a '~' in their wwwroot
 998                                  // log the user out when clicking on the link (before refreshing the page).
 999                                  resel.li.outerHTML = unescape(resel.li.outerHTML);
1000                              }
1001                              self.add_editing(result.elementid);
1002                          } else {
1003                              // Error - remove the dummy element
1004                              resel.parent.removeChild(resel.li);
1005                              new M.core.alert({message: result.error});
1006                          }
1007                      }
1008                  } else {
1009                      new M.core.alert({message: M.util.get_string('servererror', 'moodle')});
1010                  }
1011              }
1012          };
1013  
1014          // Prepare the data to send
1015          var formData = new FormData();
1016          formData.append('contents', contents);
1017          formData.append('displayname', name);
1018          formData.append('sesskey', M.cfg.sesskey);
1019          formData.append('course', this.courseid);
1020          formData.append('section', sectionnumber);
1021          formData.append('type', type);
1022          formData.append('module', module);
1023  
1024          // Send the data
1025          xhr.open("POST", this.url, true);
1026          xhr.send(formData);
1027      },
1028  
1029      /**
1030       * Call the AJAX course editing initialisation to add the editing tools
1031       * to the newly-created resource link
1032       * @param elementid the id of the DOM element containing the new resource link
1033       * @param sectionnumber the number of the selected course section
1034       */
1035      add_editing: function(elementid) {
1036          var node = Y.one('#' + elementid);
1037          YUI().use('moodle-course-coursebase', function(Y) {
1038              Y.log("Invoking setup_for_resource", 'debug', 'coursedndupload');
1039              M.course.coursebase.invoke_function('setup_for_resource', node);
1040          });
1041          if (M.core.actionmenu && M.core.actionmenu.newDOMNode) {
1042              M.core.actionmenu.newDOMNode(node);
1043          }
1044      }
1045  };