skins/fileupload.js

   1 // © 2013 Benoît Pin MINES ParisTech
   2 var DDFileUploaderBase;
   3
   4 (function(){
   5 // nombre maximun d'image chargées en local
   6 var MAX_PREVIEW = 2;
   7
   8 DDFileUploaderBase = function(dropbox, uploadUrl) {
   9         this.dropbox = dropbox;
  10         this.uploadUrl = uploadUrl;
  11         this.uploadQueue = [];
  12         this._uploadQueueRunning = false;
  13         var self = this;
  14         addListener(dropbox, 'dragenter', function(evt){self.dragenter(evt);});
  15         addListener(dropbox, 'dragover', function(evt){self.dragover(evt);});
  16         addListener(dropbox, 'drop', function(evt){self.drop(evt);});
  17 };
  18
  19 // Drag and drop
  20 DDFileUploaderBase.prototype.dragenter = function(evt) {
  21         disableDefault(evt);
  22         disablePropagation(evt);
  23 };
  24
  25 DDFileUploaderBase.prototype.dragover = function(evt) {
  26         disableDefault(evt);
  27         disablePropagation(evt);
  28         evt = getEventObject(evt);
  29         var dt = evt.dataTransfer;
  30         dt.dropEffect = 'copy';
  31 };
  32
  33 DDFileUploaderBase.prototype.drop = function(evt) {
  34         disableDefault(evt);
  35         disablePropagation(evt);
  36         getEventObject(evt);
  37         var dt = evt.dataTransfer;
  38         dt.dropEffect = 'copy';
  39         this.handleFiles(dt.files);
  40 };
  41
  42 // Methods about upload
  43 DDFileUploaderBase.prototype.handleFiles = function(files) {
  44         var file, i, slide;
  45         for (i = 0; i < files.length; i++) {
  46                 file = files[i];
  47                 slide = this.createSlide(file);
  48         this.previewQueuePush(slide);
  49         this.uploadQueuePush(slide);
  50         }
  51 };
  52
  53 DDFileUploaderBase.prototype.upload = function(slide) {
  54         var reader = new FileReader();
  55         var req = new XMLHttpRequest();
  56         var file = slide.file;
  57         this.uploadedSlide = slide;
  58         this.previewImg = slide.img;
  59         this.progressBar = slide.progressBar;
  60         var self = this;
  61
  62         addListener(req.upload, 'progress', function(evt){self.progressHandler(evt);});
  63         addListener(req, 'readystatechange',
  64                 function(evt) {
  65                         if (req.readyState === 4) {
  66                                 self.uploadCompleteHandler(req);
  67                         }
  68                 });
  69
  70         req.open("PUT", this.uploadUrl);
  71         req.setRequestHeader("Content-Type", file.type);
  72         req.setRequestHeader("X-File-Name", file.name);
  73         addListener(reader, 'load',
  74                 function(evt){
  75                         try {
  76                                 req.sendAsBinary(evt.target.result);
  77                         }
  78                         catch(e){}
  79                 });
  80         reader.readAsBinaryString(file);
  81 };
  82
  83 DDFileUploaderBase.prototype.uploadCompleteHandler = function(req) {
  84         var slide = this.uploadedSlide;
  85         this.uploadedSlide.removeChild(slide.label);
  86     this.uploadedSlide.removeChild(slide.progressBar);
  87         var fragment = getCopyOfNode(req.responseXML.documentElement.firstChild);
  88         var img = fragment.getElementsByTagName('img')[0];
  89         if (req.status === 200) {
  90                 // update
  91                 var existing = this.existingSlides[img.src];
  92                 if (existing) {
  93                         existing.src = existing.src + '?' + Math.random().toString();
  94                 }
  95                 slide.img.src = '';
  96                 slide.img.parentNode.removeChild(slide.img);
  97                 slide.img = undefined;
  98                 slide.parentNode.removeChild(slide);
  99         }
 100         else if(req.status === 201) {
 101                 // creation
 102                 img.onload = function(evt) {
 103                         // accelerate GC before replacing
 104                         slide.img.src = '';
 105                         slide.img.parentNode.removeChild(slide.img);
 106                         slide.img = undefined;
 107                         slide.parentNode.replaceChild(fragment, slide);
 108                 };
 109         }
 110         this.previewsLoaded--;
 111         this.previewQueueLoadNext();
 112         this.uploadQueueLoadNext();
 113 };
 114
 115 DDFileUploaderBase.prototype.progressHandler = function(evt) {
 116         if (evt.lengthComputable) {
 117                 var progress = evt.loaded / evt.total;
 118                 this.updateProgressBar(progress);
 119                 var currentOpacity = this.previewImg.style.opacity;
 120                 this.previewImg.style.opacity = Math.max(currentOpacity, progress);
 121         }
 122 };
 123
 124 // Method about queues
 125
 126 DDFileUploaderBase.prototype.previewQueuePush = function(slide) {
 127         this.previewQueue.push(slide);
 128         if (!this._previewQueueRunning) {
 129                 this.startPreviewQueue();
 130         }
 131 };
 132
 133 DDFileUploaderBase.prototype.startPreviewQueue = function() {
 134         this._previewQueueRunning = true;
 135         this.previewQueueLoadNext();
 136 };
 137
 138 DDFileUploaderBase.prototype.previewQueueLoadNext = function() {
 139         if (this.previewQueue.length && this.previewsLoaded < MAX_PREVIEW) {
 140                 var slide = this.previewQueue.shift();
 141                 this.previewUploadedImage(slide);
 142                 this.previewsLoaded++;
 143         }
 144         else {
 145                 this._previewQueueRunning = false;
 146         }
 147 };
 148
 149 DDFileUploaderBase.prototype.uploadQueuePush = function(slide) {
 150         this.uploadQueue.push(slide);
 151         if (!this._uploadQueueRunning) {
 152                 this.startUploadQueue();
 153         }
 154 };
 155
 156 DDFileUploaderBase.prototype.startUploadQueue = function() {
 157         this._uploadQueueRunning = true;
 158         this.uploadQueueLoadNext();
 159 };
 160
 161
 162 DDFileUploaderBase.prototype.uploadQueueLoadNext = function() {
 163         var slide = this.uploadQueue.shift();
 164         if (slide) {
 165                 this.upload(slide);
 166         }
 167         else {
 168                 this._uploadQueueRunning = false;
 169         }
 170 };
 171
 172
 173 // User interface
 174 DDFileUploaderBase.prototype.createSlide = function(file) {
 175         var slide = document.createElement('span');
 176         slide.file = file;
 177
 178         var a = document.createElement('a');
 179         a.href = '#';
 180         a.className = 'slide';
 181
 182         var img = document.createElement('img');
 183         img.className = 'hidden';
 184         var size = this.thumbnailSize;
 185         var self = this;
 186         img.onload = function(evt) {
 187                 if (img.width > img.height) { // landscape
 188                         img.height = Math.round(size * img.height / img.width);
 189                         img.width = size;
 190                 }
 191                 else {
 192                         img.width = Math.round(size * img.width / img.height);
 193                         img.height = size;
 194                 }
 195                 img.style.marginLeft = Math.floor((self.slideSize - img.width) / 2) + 'px';
 196                 img.style.marginTop = Math.floor((self.slideSize - img.height) / 2) + 'px';
 197                 img.style.opacity = 0.2;
 198                 img.className = undefined;
 199         };
 200         a.appendChild(img);
 201         slide.img = img;
 202
 203         var label = document.createElement('span');
 204         slide.label = label;
 205         label.className = 'label';
 206         label.innerHTML = file.name;
 207
 208         var progressBar = document.createElement('span');
 209         progressBar.className = 'upload-progress';
 210         slide.progressBar = progressBar;
 211
 212         slide.appendChild(a);
 213         slide.appendChild(progressBar);
 214         slide.appendChild(label);
 215         this.dropbox.appendChild(slide);
 216
 217         return slide;
 218 };
 219
 220 DDFileUploaderBase.prototype.updateProgressBar = function(progress) {
 221         // 0 <= progress <= 1
 222         var size = this.progressBarMaxSize * progress;
 223         size = Math.round(size);
 224         this.progressBar.style.width = size + 'px';
 225 };
 226
 227 DDFileUploaderBase.prototype.previewUploadedImage = function(slide) {
 228         var reader = new FileReader();
 229         var size = this.thumbnailSize;
 230         var self = this;
 231
 232         reader.onload = function(evt) {
 233                 slide.img.src = evt.target.result;
 234                 setTimeout(function(){self.previewQueueLoadNext();}, 500);
 235         };
 236         reader.readAsDataURL(slide.file);
 237 };
 238
 239 }());