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         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 }