git.sesse.net Git - pr0n/blob - 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         if (typeof(elem.style.opacity) != 'undefined') {            // W3C
 222                 elem.style.opacity = amount;
 223         } else if (typeof(elem.style.mozOpacity) != 'undefined') {  // older Mozilla
 224                 elem.style.mozOpacity = amount;
 225         } else if (typeof(elem.style.filter) != 'undefined') {      // IE
 226                 if (elem.style.filter.indexOf("alpha") == -1) {
 227                         // add an alpha filter if there isn't one already
 228                         if (elem.style.filter) {
 229                                 elem.style.filter += " ";
 230                         } else {
 231                                 elem.style.filter = "";
 232                         }
 233                         elem.style.filter += "alpha(opacity=" + (amount*100.0) + ")";
 234                 } else {
 235                         // ugh? this seems to break in color index mode...
 236                         if (typeof(elem.filters) == 'unknown') {
 237                                 elem.style.filter = "alpha(opacity=" + (amount*100.0) + ")";
 238                         } else {
 239                                 elem.filters.alpha.opacity = (amount * 100.0);
 240                         }
 241                 }
 242         } else {                             // no alpha support
 243                 if (amount > 0.5) {
 244                         elem.style.visibility = "visible";
 245                         elem.style.zorder = 1;
 246                 } else {
 247                         elem.style.visibility = "hidden";
 248                 }
 249         }
 250 }
 251
 252 function center_image(num)
 253 {
 254         var screen_size = find_width();
 255         var dpr = find_dpr();
 256         var width, height;
 257
 258         if (global_image_list[num][2] == -1) {
 259                 // no size information, use our pessimal guess
 260                 var adjusted_size = max_image_size(screen_size);
 261                 width = adjusted_size[0];
 262                 height = adjusted_size[1];
 263         } else {
 264                 // use the exact information
 265                 var adjusted_size = pick_image_size(screen_size, [ global_image_list[num][2], global_image_list[num][3] ]);
 266                 width = adjusted_size[2];
 267                 height = adjusted_size[3];
 268         }
 269
 270         // center the image on-screen
 271         var main = document.getElementById("main");
 272         main.style.position = "absolute";
 273         main.style.left = (((screen_size[0] - width) / 2) / dpr) + "px";
 274         main.style.top = (((screen_size[1] - height) / 2) / dpr) + "px";
 275         main.style.width = (width / dpr) + "px";
 276         main.style.height = (height / dpr) + "px";
 277         main.style.lineHeight = (height / dpr) + "px";
 278 }
 279
 280 function relayout()
 281 {
 282         var img = display_image_num(global_image_num, "image");
 283         if (can_go_next()) {
 284                 prepare_preload(img, global_image_num + 1);
 285         }
 286
 287         set_opacity("previous", can_go_previous() ? 0.7 : 0.1);
 288         set_opacity("next", can_go_next() ? 0.7 : 0.1);
 289         set_opacity("close", 0.7);
 290 }
 291
 292 function go_previous()
 293 {
 294         if (!can_go_previous()) {
 295                 return;
 296         }
 297
 298         var img = display_image_num(--global_image_num, "image");
 299         if (can_go_previous()) {
 300                 set_opacity("previous", 0.7);
 301                 prepare_preload(img, global_image_num - 1);
 302         } else {
 303                 set_opacity("previous", 0.1);
 304         }
 305         set_opacity("next", can_go_next() ? 0.7 : 0.1);
 306 }
 307
 308 function go_next()
 309 {
 310         if (!can_go_next()) {
 311                 return;
 312         }
 313
 314         var img = display_image_num(++global_image_num, "image");
 315         if (can_go_next()) {
 316                 set_opacity("next", 0.7);
 317                 prepare_preload(img, global_image_num + 1);
 318         } else {
 319                 set_opacity("next", 0.1);
 320         }
 321         set_opacity("previous", can_go_previous() ? 0.7 : 0.1);
 322 }
 323
 324 function do_close()
 325 {
 326         window.location = global_return_url;
 327 }
 328
 329 function draw_text(msg)
 330 {
 331         // remove any text we might have left
 332         var text = document.getElementById("text");
 333         if (text !== null) {
 334                 text.parentNode.removeChild(text);
 335         }
 336
 337         text = document.createElement("p");
 338         text.id = "text";
 339         text.style.position = "absolute";
 340         text.style.color = "white";
 341         text.style.lineHeight = "24px";
 342         text.style.font = "24px verdana, arial, sans-serif";
 343         text.innerHTML = msg;
 344
 345         var main = document.getElementById("main");
 346         main.appendChild(text);
 347
 348         text.style.left = (main.clientWidth - text.clientWidth) / 2 + "px";
 349         text.style.top = (main.clientHeight - text.clientHeight) / 2 + "px";
 350 }
 351
 352 function fade_text(opacity)
 353 {
 354         set_opacity("text", opacity);
 355         if (opacity > 0.0) {
 356                 opacity -= 0.03;
 357                 if (opacity < 0.0) {
 358                         opacity = 0.0;
 359                 }
 360                 setTimeout("fade_text(" + opacity + ")", 30);
 361         } else {
 362                 var text = document.getElementById("text");
 363                 if (text !== null) {
 364                         text.parentNode.removeChild(text);
 365                 }
 366         }
 367 }
 368
 369 function select_image(evt, filename, selected)
 370 {
 371         if (!req) {
 372                 return;
 373         }
 374
 375         if (selected) {
 376                 draw_text("Selecting " + filename + "...");
 377         } else {
 378                 draw_text("Unselecting " + filename + "...");
 379         }
 380
 381         req.open("POST", window.location.origin + "/select", false);
 382         req.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
 383         req.send("event=" + evt + "&filename=" + filename + "&selected=" + selected);
 384
 385         setTimeout("fade_text(0.99)", 30);
 386 }
 387
 388 function key_down(which)
 389 {
 390         if (which == 39) {   // right
 391                 if (can_go_next()) {
 392                         set_opacity("next", 0.99);
 393                 }
 394         } else if (which == 37) {   // left
 395                 if (can_go_previous()) {
 396                         set_opacity("previous", 0.99);
 397                 }
 398         } else if (which == 27) {   // escape
 399                 set_opacity("close", 0.99);
 400         } else {
 401                 check_for_hash_change();
 402         }
 403 }
 404
 405 function key_up(which) {
 406         if (which == 39) {   // right
 407                 if (can_go_next()) {
 408                         set_opacity("next", 0.7);
 409                         go_next();
 410                 }
 411         } else if (which == 37) {   // left
 412                 if (can_go_previous()) {
 413                         set_opacity("previous", 0.7);
 414                         go_previous();
 415                 }
 416         } else if (which == 27) {   // escape
 417                 set_opacity("close", 0.7);
 418                 do_close();
 419         } else if (which == 32 && global_select) {   // space
 420                 select_image(global_image_list[global_image_num][0], global_image_list[global_image_num][1], 1);
 421         } else if (which == 85 && global_select) {   // u
 422                 select_image(global_image_list[global_image_num][0], global_image_list[global_image_num][1], 0);
 423         } else {
 424                 check_for_hash_change();
 425         }
 426 }
 427
 428 function parse_image_num(default_value) {
 429         var num = parseInt(window.location.hash.substr(1));
 430         if (num >= 1 && num <= global_image_list.length) {  // and then num != NaN
 431                 return (num - 1);
 432         } else {
 433                 return default_value;
 434         }
 435 }
 436
 437 function check_for_hash_change() {
 438         var num = parse_image_num(-1);
 439         if (num != -1 && num != global_image_num) {
 440                 global_image_num = num;
 441                 relayout();
 442         }
 443 }