skins/fileupload.js

   1 // © 2013 Benoît Pin MINES ParisTech
   2 var DDFileUploader;
   3
   4 (function(){
   5
   6 DDFileUploader = function(dropbox, uploadUrl) {
   7         this.dropbox = dropbox;
   8         this.uploadUrl = uploadUrl;
   9         this.slideSize = 222;
  10         this.progressBarMaxSize = 200; // pixels
  11         this.thumbnailSize = 180;
  12         this.previewQueue = [];
  13         this._previewQueueRunning = false;
  14         this.uploadQueue = [];
  15         this._uploadQueueRunning = false;
  16         var self = this;
  17         addListener(dropbox, 'dragenter', function(evt){self.dragenter(evt);});
  18         addListener(dropbox, 'dragover', function(evt){self.dragover(evt);});
  19         addListener(dropbox, 'drop', function(evt){self.drop(evt);});
  20 };
  21
  22 // Drag and drop
  23 DDFileUploader.prototype.dragenter = function(evt) {
  24         disableDefault(evt);
  25         disablePropagation(evt);
  26 };
  27
  28 DDFileUploader.prototype.dragover = function(evt) {
  29         disableDefault(evt);
  30         disablePropagation(evt);
  31         evt = getEventObject(evt);
  32         var dt = evt.dataTransfer;
  33         dt.dropEffect = 'copy';
  34 };
  35
  36 DDFileUploader.prototype.drop = function(evt) {
  37         disableDefault(evt);
  38         disablePropagation(evt);
  39         getEventObject(evt);
  40         var dt = evt.dataTransfer;
  41         dt.dropEffect = 'copy';
  42         this.handleFiles(dt.files);
  43 };
  44
  45 // Methods about upload
  46 DDFileUploader.prototype.handleFiles = function(files) {
  47         var file, i, slide;
  48         for (i = 0; i < files.length; i++) {
  49                 file = files[i];
  50                 slide = this.createSlide(file);
  51         // this.previewQueuePush(slide);
  52         this.uploadQueuePush(slide);
  53         }
  54 };
  55
  56 DDFileUploader.prototype.upload = function(slide) {
  57         var reader = new FileReader();
  58         var req = new XMLHttpRequest();
  59         var file = slide.file;
  60         this.uploadedSlide = slide;
  61         this.previewImg = slide.img;
  62         this.progressBar = slide.progressBar;
  63         var self = this;
  64
  65         addListener(req.upload, 'progress', function(evt){self.progressHandler(evt);});
  66         addListener(req.upload, 'load', function(evt){self.uploadCompleteHandler(evt);});
  67
  68         req.open("PUT", this.uploadUrl);
  69         req.setRequestHeader("Content-Type", file.type);
  70         req.setRequestHeader("X-File-Name", file.name);
  71         addListener(reader, 'load',
  72                 function(evt){
  73                         console.info('load');
  74                         try {
  75                                 req.sendAsBinary(evt.target.result);
  76                         }
  77                         catch(e){}
  78                 });
  79         reader.readAsBinaryString(file);
  80 };
  81
  82 DDFileUploader.prototype.uploadCompleteHandler = function(evt) {
  83         var slide = this.uploadedSlide;
  84         this.uploadedSlide.removeChild(slide.label);
  85     this.uploadedSlide.removeChild(slide.progressBar);
  86         this.uploadQueueLoadNext();
  87 };
  88
  89 DDFileUploader.prototype.progressHandler = function(evt) {
  90         if (evt.lengthComputable) {
  91                 var progress = evt.loaded / evt.total;
  92                 this.updateProgressBar(progress);
  93                 var currentOpacity = this.previewImg.style.opacity;
  94                 this.previewImg.style.opacity = Math.max(currentOpacity, progress);
  95         }
  96 };
  97
  98 // Method about queues
  99
 100 DDFileUploader.prototype.previewQueuePush = function(slide) {
 101         this.previewQueue.push(slide);
 102         if (!this._previewQueueRunning) {
 103                 this.startPreviewQueue();
 104         }
 105 };
 106
 107 DDFileUploader.prototype.startPreviewQueue = function() {
 108         this._previewQueueRunning = true;
 109         this.previewQueueLoadNext();
 110 };
 111
 112 DDFileUploader.prototype.previewQueueLoadNext = function() {
 113         var slide = this.previewQueue.shift();
 114         if (slide) {
 115                 this.previewUploadedImage(slide);
 116         }
 117         else {
 118                 this._previewQueueRunning = false;
 119         }
 120 };
 121
 122 DDFileUploader.prototype.uploadQueuePush = function(slide) {
 123         this.uploadQueue.push(slide);
 124         if (!this._uploadQueueRunning) {
 125                 this.startUploadQueue();
 126         }
 127 };
 128
 129 DDFileUploader.prototype.startUploadQueue = function() {
 130         this._uploadQueueRunning = true;
 131         this.uploadQueueLoadNext();
 132 };
 133
 134
 135 DDFileUploader.prototype.uploadQueueLoadNext = function() {
 136         var slide = this.uploadQueue.shift();
 137         if (slide) {
 138                 this.upload(slide);
 139         }
 140         else {
 141                 this._uploadQueueRunning = false;
 142         }
 143 };
 144
 145
 146 // User interface
 147 DDFileUploader.prototype.createSlide = function(file) {
 148         var slide = document.createElement('span');
 149         slide.file = file;
 150
 151         var a = document.createElement('a');
 152         a.href = '#';
 153         a.className = 'slide';
 154
 155         var img = document.createElement('img');
 156         img.className = 'hidden';
 157         var size = this.thumbnailSize;
 158         var self = this;
 159         img.onload = function(evt) {
 160                 if (img.width > img.height) { // landscape
 161                         img.height = Math.round(size * img.height / img.width);
 162                         img.width = size;
 163                 }
 164                 else {
 165                         img.width = Math.round(size * img.width / img.height);
 166                         img.height = size;
 167                 }
 168                 img.style.marginLeft = Math.round((self.slideSize - img.width) / 2) + 'px';
 169                 img.style.marginTop = Math.round((self.slideSize - img.height) / 2) + 'px';
 170                 img.style.opacity = 0.2;
 171                 img.className = undefined;
 172         };
 173         a.appendChild(img);
 174         slide.img = img;
 175
 176         var label = document.createElement('span');
 177         slide.label = label;
 178         label.className = 'label';
 179         label.innerHTML = file.name;
 180
 181         var progressBar = document.createElement('span');
 182         progressBar.className = 'upload-progress';
 183         slide.progressBar = progressBar;
 184
 185         slide.appendChild(a);
 186         slide.appendChild(progressBar);
 187         slide.appendChild(label);
 188         this.dropbox.appendChild(slide);
 189
 190         return slide;
 191 };
 192
 193 DDFileUploader.prototype.updateProgressBar = function(progress) {
 194         // 0 <= progress <= 1
 195         var size = this.progressBarMaxSize * progress;
 196         size = Math.round(size);
 197         this.progressBar.style.width = size + 'px';
 198 };
 199
 200 DDFileUploader.prototype.previewUploadedImage = function(slide) {
 201         var reader = new FileReader();
 202         var size = this.thumbnailSize;
 203         var self = this;
 204
 205         reader.onload = function(evt) {
 206                 slide.img.src = evt.target.result;
 207                 setTimeout(function(){self.previewQueueLoadNext();}, 500);
 208         };
 209         reader.readAsDataURL(slide.file);
 210 };
 211
 212 }());