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 + '/' + file.name);
  69         req.setRequestHeader("Content-Type", file.type);
  70         addListener(reader, 'load',
  71                 function(evt){
  72                         console.info('load');
  73                         try {
  74                                 req.sendAsBinary(evt.target.result);
  75                         }
  76                         catch(e){}
  77                 });
  78         reader.readAsBinaryString(file);
  79 };
  80
  81 DDFileUploader.prototype.uploadCompleteHandler = function(evt) {
  82         var slide = this.uploadedSlide;
  83         this.uploadedSlide.removeChild(slide.label);
  84         this.uploadedSlide.removeChild(slide.label);
  85         this.uploadQueueLoadNext();
  86 };
  87
  88 DDFileUploader.prototype.progressHandler = function(evt) {
  89         if (evt.lengthComputable) {
  90                 var progress = evt.loaded / evt.total;
  91                 this.updateProgressBar(progress);
  92                 var currentOpacity = this.previewImg.style.opacity;
  93                 this.previewImg.style.opacity = Math.max(currentOpacity, progress);
  94         }
  95 };
  96
  97 // Method about queues
  98
  99 DDFileUploader.prototype.previewQueuePush = function(slide) {
 100         this.previewQueue.push(slide);
 101         if (!this._previewQueueRunning) {
 102                 this.startPreviewQueue();
 103         }
 104 };
 105
 106 DDFileUploader.prototype.startPreviewQueue = function() {
 107         this._previewQueueRunning = true;
 108         this.previewQueueLoadNext();
 109 };
 110
 111 DDFileUploader.prototype.previewQueueLoadNext = function() {
 112         var slide = this.previewQueue.shift();
 113         if (slide) {
 114                 this.previewUploadedImage(slide);
 115         }
 116         else {
 117                 this._previewQueueRunning = false;
 118         }
 119 };
 120
 121 DDFileUploader.prototype.uploadQueuePush = function(slide) {
 122         this.uploadQueue.push(slide);
 123         if (!this._uploadQueueRunning) {
 124                 this.startUploadQueue();
 125         }
 126 };
 127
 128 DDFileUploader.prototype.startUploadQueue = function() {
 129         this._uploadQueueRunning = true;
 130         this.uploadQueueLoadNext();
 131 };
 132
 133
 134 DDFileUploader.prototype.uploadQueueLoadNext = function() {
 135         var slide = this.uploadQueue.shift();
 136         if (slide) {
 137                 this.upload(slide);
 138         }
 139         else {
 140                 this._uploadQueueRunning = false;
 141         }
 142 };
 143
 144
 145 // User interface
 146 DDFileUploader.prototype.createSlide = function(file) {
 147         var slide = document.createElement('span');
 148         slide.file = file;
 149
 150         var a = document.createElement('a');
 151         a.href = '#';
 152         a.className = 'slide';
 153
 154         var img = document.createElement('img');
 155         img.className = 'hidden';
 156         var size = this.thumbnailSize;
 157         var self = this;
 158         img.onload = function(evt) {
 159                 if (img.width > img.height) { // landscape
 160                         img.height = Math.round(size * img.height / img.width);
 161                         img.width = size;
 162                 }
 163                 else {
 164                         img.width = Math.round(size * img.width / img.height);
 165                         img.height = size;
 166                 }
 167                 img.style.marginLeft = Math.round((self.slideSize - img.width) / 2) + 'px';
 168                 img.style.marginTop = Math.round((self.slideSize - img.height) / 2) + 'px';
 169                 img.style.opacity = 0.2;
 170                 img.className = undefined;
 171         };
 172         a.appendChild(img);
 173         slide.img = img;
 174
 175         var label = document.createElement('span');
 176         slide.label = label;
 177         label.className = 'label';
 178         label.innerHTML = file.name;
 179
 180         var progressBar = document.createElement('span');
 181         progressBar.className = 'upload-progress';
 182         slide.progressBar = progressBar;
 183
 184         slide.appendChild(a);
 185         slide.appendChild(progressBar);
 186         slide.appendChild(label);
 187         this.dropbox.appendChild(slide);
 188
 189         return slide;
 190 };
 191
 192 DDFileUploader.prototype.updateProgressBar = function(progress) {
 193         // 0 <= progress <= 1
 194         var size = this.progressBarMaxSize * progress;
 195         size = Math.round(size);
 196         this.progressBar.style.width = size + 'px';
 197 };
 198
 199 DDFileUploader.prototype.previewUploadedImage = function(slide) {
 200         var reader = new FileReader();
 201         var size = this.thumbnailSize;
 202         var self = this;
 203
 204         reader.onload = function(evt) {
 205                 slide.img.src = evt.target.result;
 206                 setTimeout(function(){self.previewQueueLoadNext();}, 500);
 207         };
 208         reader.readAsDataURL(slide.file);
 209 };
 210
 211 }());