905ccf7e0001c33b089fe6684bfa50834cd5526c
[Plinn.git] / 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.previewImg = slide.img;
61 this.progressBar = slide.progressBar;
62 var self = this;
63
64 addListener(req.upload, 'progress', function(evt){self.progressHandler(evt);});
65 addListener(req.upload, 'load', function(evt){self.uploadCompleteHandler(evt);});
66
67 req.open("PUT", this.uploadUrl + '/' + file.name);
68 req.setRequestHeader("Content-Type", file.type);
69 addListener(reader, 'load', function(evt){req.sendAsBinary(evt.target.result);});
70 reader.readAsBinaryString(file);
71 };
72
73 DDFileUploader.prototype.uploadCompleteHandler = function(evt) {
74 this.progressBar.parentNode.removeChild(this.progressBar);
75 this.uploadQueueLoadNext();
76 };
77
78 DDFileUploader.prototype.progressHandler = function(evt) {
79 if (evt.lengthComputable) {
80 var progress = evt.loaded / evt.total;
81 this.updateProgressBar(progress);
82 var currentOpacity = this.previewImg.style.opacity;
83 this.previewImg.style.opacity = Math.max(currentOpacity, progress);
84 }
85 };
86
87 // Method about queues
88
89 DDFileUploader.prototype.previewQueuePush = function(slide) {
90 this.previewQueue.push(slide);
91 if (!this._previewQueueRunning)
92 this.startPreviewQueue();
93 };
94
95 DDFileUploader.prototype.startPreviewQueue = function() {
96 this._previewQueueRunning = true;
97 this.previewQueueLoadNext();
98 };
99
100 DDFileUploader.prototype.previewQueueLoadNext = function() {
101 var slide = this.previewQueue.shift();
102 if (slide)
103 this.previewUploadedImage(slide);
104 else
105 this._previewQueueRunning = false;
106 };
107
108 DDFileUploader.prototype.uploadQueuePush = function(slide) {
109 this.uploadQueue.push(slide);
110 if (!this._uploadQueueRunning)
111 this.startUploadQueue();
112 };
113
114 DDFileUploader.prototype.startUploadQueue = function() {
115 this._uploadQueueRunning = true;
116 this.uploadQueueLoadNext();
117 };
118
119
120 DDFileUploader.prototype.uploadQueueLoadNext = function() {
121 var slide = this.uploadQueue.shift();
122 if (slide)
123 this.upload(slide);
124 else
125 this._uploadQueueRunning = false;
126 };
127
128
129 // User interface
130 DDFileUploader.prototype.createSlide = function(file) {
131 var slide = document.createElement('span');
132 slide.file = file;
133
134 var a = document.createElement('a');
135 a.href = '#';
136 a.className = 'slide';
137
138 var img = document.createElement('img');
139 img.className = 'hidden';
140 var size = this.thumbnailSize;
141 var self = this;
142 img.onload = function(evt) {
143 if (img.width > img.height) { // landscape
144 img.height = Math.round(size * img.height / img.width);
145 img.width = size;
146 }
147 else {
148 img.width = Math.round(size * img.width / img.height);
149 img.height = size;
150 }
151 img.style.marginLeft = Math.round((self.slideSize - img.width) / 2) + 'px';
152 img.style.marginTop = Math.round((self.slideSize - img.height) / 2) + 'px';
153 img.style.opacity = 0.2;
154 img.className = undefined;
155 };
156 a.appendChild(img);
157 slide.img = img;
158
159 var progressBar = document.createElement('span');
160 progressBar.className = 'upload-progress';
161 slide.progressBar = progressBar;
162
163 slide.appendChild(a);
164 slide.appendChild(progressBar);
165 this.dropbox.appendChild(slide);
166
167 return slide;
168 };
169
170 DDFileUploader.prototype.updateProgressBar = function(progress) {
171 // 0 <= progress <= 1
172 var size = this.progressBarMaxSize * progress;
173 size = Math.round(size);
174 this.progressBar.style.width = size + 'px';
175 };
176
177 DDFileUploader.prototype.previewUploadedImage = function(slide) {
178 var reader = new FileReader();
179 var size = this.thumbnailSize;
180 var self = this;
181
182 reader.onload = function(evt) {
183 slide.img.src = evt.target.result;
184 setTimeout(function(){self.previewQueueLoadNext();}, 500);
185 };
186 reader.readAsDataURL(slide.file);
187 };
188
189 }());