Remove more obsolete browser hacks.
[pr0n] / files / pr0n-fullscreen.js
1 var req;
2
3 function init_ajax()
4 {
5         req = new XMLHttpRequest();
6 }
7
8 function find_width()
9 {
10         var dpr = find_dpr();
11         return [window.innerWidth * dpr, window.innerHeight * dpr];
12 }
13
14 function find_dpr()
15 {
16         return window.devicePixelRatio || 1;
17 }
18
19 /*
20  * pr0n can resize to any size we'd like, but we're much more likely
21  * to have this set of fixed-resolution screens cached, so to increase
22  * performance, we round down to the closest fit and use that. This 
23  * function is a pessimal estimate of what thumbnail size we can _always_
24  * fit on the screen -- it's right if and only if all images are 4:3
25  * (and landscape). If individual size information is available, use
26  * pick_image_size, below.
27  */
28 var fixed_sizes = [
29         [ 2304, 1728 ],
30         [ 2048, 1536 ],
31         [ 1920, 1440 ],
32         [ 1600, 1200 ],
33         [ 1400, 1050 ],
34         [ 1280, 960 ],
35         [ 1152, 864 ],
36         [ 1024, 768 ],
37         [ 800, 600 ],
38         [ 640, 480 ],
39         [ 512, 384 ],
40         [ 320, 256 ],
41         [ 240, 192 ],
42         [ 120, 96 ],
43         [ 80, 64 ]
44 ];
45 function max_image_size(screen_size)
46 {
47         var i;
48         for (i = 0; i < fixed_sizes.length; ++i) {
49                 if (screen_size[0] >= fixed_sizes[i][0] && screen_size[1] >= fixed_sizes[i][1]) {
50                         return fixed_sizes[i];
51                 }
52         }
53         return [ 80, 64 ];
54 }
55
56 function pick_image_size(screen_size, image_size)
57 {
58         var i;
59         for (i = 0; i < fixed_sizes.length; ++i) {
60                 // this is a duplicate of pr0n's resizing code, hope for no floating-point
61                 // inaccuracies :-)
62                 var thumbxres = fixed_sizes[i][0];
63                 var thumbyres = fixed_sizes[i][1];
64                 var width = image_size[0];
65                 var height = image_size[1];
66
67                 if (!(thumbxres >= width && thumbyres >= height)) {
68                         var sfh = width / thumbxres;
69                         var sfv = height / thumbyres;
70                         if (sfh > sfv) {
71                                 width  /= sfh;
72                                 height /= sfh;
73                         } else {
74                                 width  /= sfv;
75                                 height /= sfv;
76                         }
77                         width = Math.floor(width);
78                         height = Math.floor(height);
79                 }
80
81                 if (screen_size[0] >= width && screen_size[1] >= height) {
82                         // be sure _not_ to return a reference
83                         return [ fixed_sizes[i][0], fixed_sizes[i][1], width, height ];
84                 }
85         }
86         return [ 80, 64 ];
87 }
88
89 function replace_image_element(url, element_id, parent_node)
90 {
91         var img = document.getElementById(element_id);
92         if (img !== null) {
93                 if (img.src === url) {
94                         return img;
95                 }
96                 img.parentNode.removeChild(img);
97         }
98
99         img = document.createElement("img");
100         img.id = element_id;
101         img.alt = "";
102         img.src = url;
103         parent_node.appendChild(img);
104         return img;
105 }
106
107 function rename_element(old_name, new_name)
108 {
109         // Remove any element that's in the way.
110         var elem = document.getElementById(new_name);
111         if (elem !== null) {
112                 elem.parentNode.removeChild(elem);
113         }
114
115         elem = document.getElementById(old_name);
116         if (elem !== null) {
117                 elem.id = new_name;
118         }
119         return elem;
120 }
121
122 function display_image(width, height, evt, filename, element_id)
123 {
124         var url = window.location.origin + "/" + evt + "/" + width + "x" + height + "/nobox/" + filename;
125         var main = document.getElementById("iehack");
126         var preload = document.getElementById("preload");
127         var dpr = find_dpr();
128         var img;
129         // See if we have a preload going on that we can reuse.
130         if (element_id == "image" && preload !== null && preload.src == url) {
131                 rename_element("preload_box", "image_box");
132                 img = rename_element("preload", "image");
133         } else {
134                 img = replace_image_element(url, element_id, main);
135         }
136         img.style.position = "absolute";
137         img.style.left = "0px";
138         img.style.top = "0px";
139         img.style.transformOrigin = "top left";
140         img.style.transform = "scale(" + (1.0 / dpr) + ")";
141
142         // Infobox.
143         var url;
144         if (dpr == 1) {
145                 url = window.location.origin + "/" + evt + "/" + width + "x" + height + "/box/" + filename;
146         } else {
147                 url = window.location.origin + "/" + evt + "/" + width + "x" + height + "@" + dpr.toFixed(2) + "/box/" + filename;
148         }
149         var boximg = replace_image_element(url, element_id + "_box", main);
150
151         boximg.style.position = "absolute";
152         boximg.style.left = "0px";
153         boximg.style.bottom = "-1px";
154         boximg.style.transformOrigin = "bottom left";
155         boximg.style.transform = "scale(" + (1.0 / dpr) + ")";
156
157         return img;
158 }
159
160 function display_image_num(num, element_id)
161 {
162         var screen_size = find_width();
163         var adjusted_size;
164
165         if (global_image_list[num][2] == -1) {
166                 // no size information, use our pessimal guess
167                 adjusted_size = max_image_size(screen_size);
168         } else {
169                 adjusted_size = pick_image_size(screen_size, [ global_image_list[num][2], global_image_list[num][3] ]);
170         }
171
172         var img = display_image(adjusted_size[0], adjusted_size[1], global_image_list[num][0], global_image_list[num][1], element_id);
173         
174         if (element_id == "image") {
175                 // we want to shrink the box as much as possible if we know the true
176                 // size of the image
177                 center_image(num);
178                 
179                 // replace the anchor part (if any) with the image number
180                 window.location.hash = "#" + (num+1);
181         }
182
183         return img;
184 }
185
186 function prepare_preload(img, num)
187 {
188         // cancel any pending preload
189         var preload = document.getElementById("preload");
190         if (preload !== null) {
191                 preload.parentNode.removeChild(preload);
192         }
193         
194         var preload_box = document.getElementById("preload_box");
195         if (preload_box !== null) {
196                 preload_box.parentNode.removeChild(preload_box);
197         }
198
199         // grmf -- IE doesn't fire onload if the image was loaded from cache, so check for
200         // completeness first; should at least be _somewhat_ better
201         if (img.complete) {
202                 display_image_num(num, "preload");
203         } else {
204                 img.onload = function() { display_image_num(num, "preload"); };
205         }       
206 }
207
208 function can_go_next()
209 {
210         return (global_image_num < global_image_list.length - 1);
211 }
212
213 function can_go_previous()
214 {
215         return (global_image_num > 0);
216 }
217
218 function set_opacity(id, amount)
219 {
220         var elem = document.getElementById(id);
221         elem.style.opacity = amount;
222 }
223
224 function center_image(num)
225 {
226         var screen_size = find_width();
227         var dpr = find_dpr();
228         var width, height;
229         
230         if (global_image_list[num][2] == -1) {
231                 // no size information, use our pessimal guess
232                 var adjusted_size = max_image_size(screen_size);
233                 width = adjusted_size[0];
234                 height = adjusted_size[1];
235         } else {
236                 // use the exact information
237                 var adjusted_size = pick_image_size(screen_size, [ global_image_list[num][2], global_image_list[num][3] ]);
238                 width = adjusted_size[2];
239                 height = adjusted_size[3];
240         }
241
242         // center the image on-screen
243         var main = document.getElementById("main");
244         main.style.position = "absolute";
245         main.style.left = (((screen_size[0] - width) / 2) / dpr) + "px";
246         main.style.top = (((screen_size[1] - height) / 2) / dpr) + "px";
247         main.style.width = (width / dpr) + "px";
248         main.style.height = (height / dpr) + "px";
249         main.style.lineHeight = (height / dpr) + "px";
250 }
251
252 function relayout()
253 {
254         var img = display_image_num(global_image_num, "image");
255         if (can_go_next()) {
256                 prepare_preload(img, global_image_num + 1);
257         }
258
259         set_opacity("previous", can_go_previous() ? 0.7 : 0.1);
260         set_opacity("next", can_go_next() ? 0.7 : 0.1);
261         set_opacity("close", 0.7);
262 }
263
264 function go_previous()
265 {
266         if (!can_go_previous()) {
267                 return;
268         }
269
270         var img = display_image_num(--global_image_num, "image");
271         if (can_go_previous()) {
272                 set_opacity("previous", 0.7);
273                 prepare_preload(img, global_image_num - 1);
274         } else {
275                 set_opacity("previous", 0.1);
276         }
277         set_opacity("next", can_go_next() ? 0.7 : 0.1);
278 }
279
280 function go_next()
281 {
282         if (!can_go_next()) {
283                 return;
284         }
285
286         var img = display_image_num(++global_image_num, "image");
287         if (can_go_next()) {
288                 set_opacity("next", 0.7);
289                 prepare_preload(img, global_image_num + 1);
290         } else {
291                 set_opacity("next", 0.1);
292         }
293         set_opacity("previous", can_go_previous() ? 0.7 : 0.1);
294 }
295
296 function do_close()
297 {
298         window.location = global_return_url;
299 }
300
301 function draw_text(msg)
302 {
303         // remove any text we might have left
304         var text = document.getElementById("text");
305         if (text !== null) {
306                 text.parentNode.removeChild(text);
307         }
308
309         text = document.createElement("p");
310         text.id = "text";
311         text.style.position = "absolute";
312         text.style.color = "white";
313         text.style.lineHeight = "24px";
314         text.style.font = "24px verdana, arial, sans-serif";
315         text.innerHTML = msg;
316
317         var main = document.getElementById("main");
318         main.appendChild(text);
319
320         text.style.left = (main.clientWidth - text.clientWidth) / 2 + "px";
321         text.style.top = (main.clientHeight - text.clientHeight) / 2 + "px";
322 }
323
324 function fade_text(opacity)
325 {
326         set_opacity("text", opacity);
327         if (opacity > 0.0) {
328                 opacity -= 0.03;
329                 if (opacity < 0.0) {
330                         opacity = 0.0;
331                 }
332                 setTimeout("fade_text(" + opacity + ")", 30);
333         } else {
334                 var text = document.getElementById("text");
335                 if (text !== null) {
336                         text.parentNode.removeChild(text);
337                 }
338         }
339 }
340
341 function select_image(evt, filename, selected)
342 {
343         if (!req) {
344                 return;
345         }
346
347         if (selected) {
348                 draw_text("Selecting " + filename + "...");
349         } else {
350                 draw_text("Unselecting " + filename + "...");
351         }
352         
353         req.open("POST", window.location.origin + "/select", false);
354         req.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
355         req.send("event=" + evt + "&filename=" + filename + "&selected=" + selected);
356
357         setTimeout("fade_text(0.99)", 30);
358 }
359
360 function key_down(which)
361 {
362         if (which == 39) {   // right
363                 if (can_go_next()) {
364                         set_opacity("next", 0.99);
365                 }
366         } else if (which == 37) {   // left
367                 if (can_go_previous()) {
368                         set_opacity("previous", 0.99);
369                 }
370         } else if (which == 27) {   // escape
371                 set_opacity("close", 0.99);
372         } else {
373                 check_for_hash_change();
374         }
375 }
376
377 function key_up(which) {
378         if (which == 39) {   // right
379                 if (can_go_next()) {
380                         set_opacity("next", 0.7);
381                         go_next();
382                 }
383         } else if (which == 37) {   // left
384                 if (can_go_previous()) {
385                         set_opacity("previous", 0.7);
386                         go_previous();
387                 }
388         } else if (which == 27) {   // escape
389                 set_opacity("close", 0.7);
390                 do_close();
391         } else if (which == 32 && global_select) {   // space
392                 select_image(global_image_list[global_image_num][0], global_image_list[global_image_num][1], 1);
393         } else if (which == 85 && global_select) {   // u
394                 select_image(global_image_list[global_image_num][0], global_image_list[global_image_num][1], 0);
395         } else {
396                 check_for_hash_change();
397         }
398 }
399
400 function parse_image_num(default_value) {
401         var num = parseInt(window.location.hash.substr(1));
402         if (num >= 1 && num <= global_image_list.length) {  // and then num != NaN
403                 return (num - 1);
404         } else {
405                 return default_value;
406         }
407 }
408
409 function check_for_hash_change() {
410         var num = parse_image_num(-1);
411         if (num != -1 && num != global_image_num) {
412                 global_image_num = num;
413                 relayout();
414         }
415 }