Optimisation du chargement des vignettes juxtaposées à celle affichée.
[Portfolio.git] / skins / portfolio_upload.js
1 // © 2013 Benoît Pin MINES ParisTech
2
3 var DDImageUploader;
4
5 (function(){
6 // nombre maximun d'image chargées en local
7 var MAX_PREVIEW = 2;
8 var isThumbnail = /.*\/getThumbnail$/;
9
10 DDImageUploader = function(dropbox, uploadUrl, options) {
11 DDFileUploaderBase.apply(this, [dropbox, uploadUrl]);
12
13 this.existingSlides = this.indexExistingSlides();
14 this.slideSize = options.slideSize || 222; // pixels
15 this.progressBarMaxSize = this.slideSize - 22 || 200;
16 this.thumbnailSize = options.thumbnailSize || 180;
17 this.previewQueue = [];
18 this._previewQueueRunning = false;
19 this.previewsLoaded = 0;
20 };
21
22 copyPrototype(DDImageUploader, DDFileUploaderBase);
23
24 DDImageUploader.prototype.indexExistingSlides = function() {
25 var images = this.dropbox.getElementsByTagName('img');
26 var i;
27 var index = [];
28 for (i=0 ; i < images.length ; i++) {
29 if (isThumbnail.test(images[i].src)) {
30 index[images[i].src] = images[i]; }
31 }
32 return index;
33 };
34
35 // Methods about upload.
36 DDImageUploader.prototype.handleFiles = function(files) {
37 var file, i, slide;
38 for (i = 0; i < files.length; i++) {
39 file = files[i];
40 slide = this.createSlide(file);
41 this.previewQueuePush(slide);
42 this.uploadQueuePush(slide);
43 }
44 };
45
46 DDImageUploader.prototype.beforeUpload = function(slide) {
47 this.uploadedSlide = slide;
48 this.previewImg = slide.img;
49 this.progressBar = slide.progressBar;
50 this.scrollToSlide(slide);
51 };
52
53 DDImageUploader.prototype.scrollToSlide = function(slide) {
54 var slideHeight = slide.offsetHeight;
55 var slideOffsetTop = slide.getElementsByClassName('slide')[0].offsetTop;
56 var to = slideOffsetTop - getWindowHeight() + slideHeight;
57 window.scroll(0, to);
58 };
59
60 DDImageUploader.prototype.uploadCompleteHandlerCB = function(req) {
61 var slide = this.uploadedSlide;
62 this.uploadedSlide.removeChild(slide.label);
63 this.uploadedSlide.removeChild(slide.progressBar);
64 var fragment = getCopyOfNode(req.responseXML.documentElement.firstChild);
65 var img = fragment.getElementsByTagName('img')[0];
66 if (req.status === 200) {
67 // update
68 var existing = this.existingSlides[img.src];
69 if (existing) {
70 existing.src = existing.src + '?' + Math.random().toString();
71 }
72 slide.img.src = '';
73 slide.img.parentNode.removeChild(slide.img);
74 slide.img = undefined;
75 slide.parentNode.removeChild(slide);
76 }
77 else if(req.status === 201) {
78 // creation
79 img.onload = function(evt) {
80 // accelerate GC before replacing
81 slide.img.src = '';
82 slide.img.parentNode.removeChild(slide.img);
83 slide.img = undefined;
84 slide.parentNode.replaceChild(fragment, slide);
85 };
86 }
87 this.previewsLoaded--;
88 this.previewQueueLoadNext();
89 };
90
91 DDImageUploader.prototype.progressHandlerCB = function(progress) {
92 this.updateProgressBar(progress);
93 var currentOpacity = this.previewImg.style.opacity;
94 this.previewImg.style.opacity = Math.max(currentOpacity, progress);
95 };
96
97 // Methods about preview queue.
98 DDImageUploader.prototype.previewQueuePush = function(slide) {
99 this.previewQueue.push(slide);
100 if (!this._previewQueueRunning) {
101 this.startPreviewQueue();
102 }
103 };
104
105 DDImageUploader.prototype.startPreviewQueue = function() {
106 this._previewQueueRunning = true;
107 this.previewQueueLoadNext();
108 };
109
110 DDImageUploader.prototype.previewQueueLoadNext = function() {
111 if (this.previewQueue.length && this.previewsLoaded < MAX_PREVIEW) {
112 var slide = this.previewQueue.shift();
113 this.previewUploadedImage(slide);
114 this.previewsLoaded++;
115 }
116 else {
117 this._previewQueueRunning = false;
118 }
119 };
120
121 // User interface
122 DDImageUploader.prototype.createSlide = function(file) {
123 var slide = document.createElement('span');
124 slide.file = file;
125
126 var a = document.createElement('a');
127 a.href = '#';
128 a.className = 'slide';
129
130 var img = document.createElement('img');
131 img.className = 'hidden';
132 var size = this.thumbnailSize;
133 var self = this;
134 img.onload = function(evt) {
135 if (img.width > img.height) { // landscape
136 img.height = Math.round(size * img.height / img.width);
137 img.width = size;
138 }
139 else {
140 img.width = Math.round(size * img.width / img.height);
141 img.height = size;
142 }
143 img.style.marginLeft = Math.floor((self.slideSize - img.width) / 2) + 'px';
144 img.style.marginTop = Math.floor((self.slideSize - img.height) / 2) + 'px';
145 img.style.opacity = 0.2;
146 img.className = undefined;
147 };
148 a.appendChild(img);
149 slide.img = img;
150
151 var label = document.createElement('span');
152 slide.label = label;
153 label.className = 'label';
154 label.innerHTML = file.name;
155
156 var progressBar = document.createElement('span');
157 progressBar.className = 'upload-progress';
158 slide.progressBar = progressBar;
159
160 slide.appendChild(a);
161 slide.appendChild(progressBar);
162 slide.appendChild(label);
163 this.dropbox.appendChild(slide);
164
165 return slide;
166 };
167
168 DDImageUploader.prototype.updateProgressBar = function(progress) {
169 // 0 <= progress <= 1
170 var size = this.progressBarMaxSize * progress;
171 size = Math.round(size);
172 this.progressBar.style.width = size + 'px';
173 };
174
175 DDImageUploader.prototype.previewUploadedImage = function(slide) {
176 var reader = new FileReader();
177 var size = this.thumbnailSize;
178 var self = this;
179
180 reader.onload = function(evt) {
181 slide.img.src = evt.target.result;
182 setTimeout(function(){self.previewQueueLoadNext();}, 500);
183 };
184 reader.readAsDataURL(slide.file);
185 };
186
187 }());