1 /*
  2     Copyright 2008-2013
  3         Matthias Ehmann,
  4         Michael Gerhaeuser,
  5         Carsten Miller,
  6         Bianca Valentin,
  7         Alfred Wassermann,
  8         Peter Wilfahrt
  9 
 10     This file is part of JSXGraph.
 11 
 12     JSXGraph is free software dual licensed under the GNU LGPL or MIT License.
 13 
 14     You can redistribute it and/or modify it under the terms of the
 15 
 16       * GNU Lesser General Public License as published by
 17         the Free Software Foundation, either version 3 of the License, or
 18         (at your option) any later version
 19       OR
 20       * MIT License: https://github.com/jsxgraph/jsxgraph/blob/master/LICENSE.MIT
 21 
 22     JSXGraph is distributed in the hope that it will be useful,
 23     but WITHOUT ANY WARRANTY; without even the implied warranty of
 24     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 25     GNU Lesser General Public License for more details.
 26 
 27     You should have received a copy of the GNU Lesser General Public License and
 28     the MIT License along with JSXGraph. If not, see <http://www.gnu.org/licenses/>
 29     and <http://opensource.org/licenses/MIT/>.
 30  */
 31 
 32 
 33 /*global JXG: true, define: true, window: true, document: true, navigator: true, module: true, global: true, self: true, require: true*/
 34 /*jslint nomen: true, plusplus: true*/
 35 
 36 /* depends:
 37  jxg
 38  utils/type
 39  */
 40 
 41 /**
 42  * @fileoverview The functions in this file help with the detection of the environment JSXGraph runs in. We can distinguish
 43  * between node.js, windows 8 app and browser, what rendering techniques are supported and (most of the time) if the device
 44  * the browser runs on is a tablet/cell or a desktop computer.
 45  */
 46 
 47 define(['jxg', 'utils/type'], function (JXG, Type) {
 48 
 49     "use strict";
 50 
 51     JXG.extend(JXG, /** @lends JXG */ {
 52         /**
 53          * Determines the property that stores the relevant information in the event object.
 54          * @type {String}
 55          * @default 'touches'
 56          */
 57         touchProperty: 'touches',
 58 
 59         /**
 60          * A document/window environment is available.
 61          * @type Boolean
 62          * @default false
 63          */
 64         isBrowser: typeof window === 'object' && typeof document === 'object',
 65 
 66         /**
 67          * Detect browser support for VML.
 68          * @returns {Boolean} True, if the browser supports VML.
 69          */
 70         supportsVML: function () {
 71             // From stackoverflow.com
 72             return this.isBrowser && !!document.namespaces;
 73         },
 74 
 75         /**
 76          * Detect browser support for SVG.
 77          * @returns {Boolean} True, if the browser supports SVG.
 78          */
 79         supportsSVG: function () {
 80             return this.isBrowser && document.implementation.hasFeature('http://www.w3.org/TR/SVG11/feature#BasicStructure', '1.1');
 81         },
 82 
 83         /**
 84          * Detect browser support for Canvas.
 85          * @returns {Boolean} True, if the browser supports HTML canvas.
 86          */
 87         supportsCanvas: function () {
 88             var c,
 89                 hasCanvas = false;
 90 
 91             if (this.isNode()) {
 92                 try {
 93                     c = (typeof module === 'object' ? module.require('canvas') : require('canvas'));
 94                     hasCanvas = true;
 95                 } catch (err) { }
 96             }
 97 
 98             return hasCanvas || (this.isBrowser && !!document.createElement('canvas').getContext);
 99         },
100 
101         /**
102          * True, if run inside a node.js environment.
103          * @returns {Boolean}
104          */
105         isNode: function () {
106             // this is not a 100% sure but should be valid in most cases
107 
108                 // we are not inside a browser
109             return !this.isBrowser && (
110                 // there is a module object (plain node, no requirejs)
111                 (typeof module === 'object' && !!module.exports) ||
112                 // there is a global object and requirejs is loaded
113                 (typeof global === 'object' && global.requirejsVars && !global.requirejsVars.isBrowser)
114             );
115         },
116 
117         /**
118          * True if run inside a webworker environment.
119          * @returns {Boolean}
120          */
121         isWebWorker: function () {
122             return !this.isBrowser && (typeof self === 'object' && typeof self.postMessage === 'function');
123         },
124 
125         /**
126          * Checks if the environments supports the W3C Pointer Events API {@link http://www.w3.org/Submission/pointer-events/}
127          * @return {Boolean}
128          */
129         supportsPointerEvents: function () {
130             return JXG.isBrowser && window.navigator && (window.navigator.msPointerEnabled || window.navigator.pointerEnabled);
131         },
132 
133         /**
134          * Determine if the current browser supports touch events
135          * @returns {Boolean} True, if the browser supports touch events.
136          */
137         isTouchDevice: function () {
138             return this.isBrowser && document.documentElement.hasOwnProperty('ontouchstart');
139         },
140 
141         /**
142          * Detects if the user is using an Android powered device.
143          * @returns {Boolean}
144          */
145         isAndroid: function () {
146             return Type.exists(navigator) && navigator.userAgent.toLowerCase().indexOf('android') > -1;
147         },
148 
149         /**
150          * Detects if the user is using the default Webkit browser on an Android powered device.
151          * @returns {Boolean}
152          */
153         isWebkitAndroid: function () {
154             return this.isAndroid() && navigator.userAgent.indexOf(' AppleWebKit/') > -1;
155         },
156 
157         /**
158          * Detects if the user is using a Apple iPad / iPhone.
159          * @returns {Boolean}
160          */
161         isApple: function () {
162             return Type.exists(navigator) && (navigator.userAgent.indexOf('iPad') > -1 || navigator.userAgent.indexOf('iPhone') > -1);
163         },
164 
165         /**
166          * Detects if the user is using Safari on an Apple device.
167          * @returns {Boolean}
168          */
169         isWebkitApple: function () {
170             return this.isApple() && (navigator.userAgent.search(/Mobile\/[0-9A-Za-z\.]*Safari/) > -1);
171         },
172 
173         /**
174          * Returns true if the run inside a Windows 8 "Metro" App.
175          * @return {Boolean}
176          */
177         isMetroApp: function () {
178             return typeof window === 'object' && window.clientInformation && window.clientInformation.appName && window.clientInformation.appName.indexOf('MSAppHost') > -1;
179         },
180 
181         /**
182          * Detects if the user is using a Mozilla browser
183          * @returns {Boolean}
184          */
185         isMozilla: function () {
186             return Type.exists(navigator) &&
187                 navigator.userAgent.toLowerCase().indexOf('mozilla') > -1 &&
188                 navigator.userAgent.toLowerCase().indexOf('apple') === -1;
189         },
190 
191         /**
192          * Detects if the user is using a firefoxOS powered device.
193          * @returns {Boolean}
194          */
195         isFirefoxOS: function () {
196             return Type.exists(navigator) &&
197                 navigator.userAgent.toLowerCase().indexOf('android') === -1 &&
198                 navigator.userAgent.toLowerCase().indexOf('apple') === -1 &&
199                 navigator.userAgent.toLowerCase().indexOf('mobile') > -1 &&
200                 navigator.userAgent.toLowerCase().indexOf('mozilla') > -1;
201         },
202 
203         /**
204          * Internet Explorer version. Works only for IE > 4.
205          * @type Number
206          */
207         ieVersion: (function () {
208             var undef, div, all,
209                 v = 3;
210 
211             if (typeof document !== 'object') {
212                 return 0;
213             }
214 
215             div = document.createElement('div');
216             all = div.getElementsByTagName('i');
217 
218             do {
219                 div.innerHTML = '<!--[if gt IE ' + (++v) + ']><' + 'i><' + '/i><![endif]-->';
220             } while (all[0]);
221 
222             return v > 4 ? v : undef;
223 
224         }()),
225 
226         /**
227          * Reads the width and height of an HTML element.
228          * @param {String} elementId The HTML id of an HTML DOM node.
229          * @returns {Object} An object with the two properties width and height.
230          */
231         getDimensions: function (elementId) {
232             var element, display, els, originalVisibility, originalPosition,
233                 originalDisplay, originalWidth, originalHeight;
234 
235             if (!JXG.isBrowser || elementId === null) {
236                 return {
237                     width: 500,
238                     height: 500
239                 };
240             }
241 
242             // Borrowed from prototype.js
243             element = document.getElementById(elementId);
244             if (!Type.exists(element)) {
245                 throw new Error("\nJSXGraph: HTML container element '" + elementId + "' not found.");
246             }
247 
248             display = element.style.display;
249 
250             // Work around a bug in Safari
251             if (display !== 'none' && display !== null) {
252                 return {width: element.offsetWidth, height: element.offsetHeight};
253             }
254 
255             // All *Width and *Height properties give 0 on elements with display set to none,
256             // hence we show the element temporarily
257             els = element.style;
258 
259             // save style
260             originalVisibility = els.visibility;
261             originalPosition = els.position;
262             originalDisplay = els.display;
263 
264             // show element
265             els.visibility = 'hidden';
266             els.position = 'absolute';
267             els.display = 'block';
268 
269             // read the dimension
270             originalWidth = element.clientWidth;
271             originalHeight = element.clientHeight;
272 
273             // restore original css values
274             els.display = originalDisplay;
275             els.position = originalPosition;
276             els.visibility = originalVisibility;
277 
278             return {
279                 width: originalWidth,
280                 height: originalHeight
281             };
282         },
283 
284         /**
285          * Adds an event listener to a DOM element.
286          * @param {Object} obj Reference to a DOM node.
287          * @param {String} type The event to catch, without leading 'on', e.g. 'mousemove' instead of 'onmousemove'.
288          * @param {Function} fn The function to call when the event is triggered.
289          * @param {Object} owner The scope in which the event trigger is called.
290          */
291         addEvent: function (obj, type, fn, owner) {
292             var el = function () {
293                 return fn.apply(owner, arguments);
294             };
295 
296             el.origin = fn;
297             owner['x_internal' + type] = owner['x_internal' + type] || [];
298             owner['x_internal' + type].push(el);
299 
300             // Non-IE browser
301             if (Type.exists(obj) && Type.exists(obj.addEventListener)) {
302                 obj.addEventListener(type, el, false);
303             }
304 
305             // IE
306             if (Type.exists(obj) && Type.exists(obj.attachEvent)) {
307                 obj.attachEvent('on' + type, el);
308             }
309         },
310 
311         /**
312          * Removes an event listener from a DOM element.
313          * @param {Object} obj Reference to a DOM node.
314          * @param {String} type The event to catch, without leading 'on', e.g. 'mousemove' instead of 'onmousemove'.
315          * @param {Function} fn The function to call when the event is triggered.
316          * @param {Object} owner The scope in which the event trigger is called.
317          */
318         removeEvent: function (obj, type, fn, owner) {
319             var i;
320 
321             if (!Type.exists(owner)) {
322                 JXG.debug('no such owner');
323                 return;
324             }
325 
326             if (!Type.exists(owner['x_internal' + type])) {
327                 JXG.debug('no such type: ' + type);
328                 return;
329             }
330 
331             if (!Type.isArray(owner['x_internal' + type])) {
332                 JXG.debug('owner[x_internal + ' + type + '] is not an array');
333                 return;
334             }
335 
336             i = Type.indexOf(owner['x_internal' + type], fn, 'origin');
337 
338             if (i === -1) {
339                 JXG.debug('no such event function in internal list: ' + fn);
340                 return;
341             }
342 
343             try {
344                 // Non-IE browser
345                 if (Type.exists(obj) && Type.exists(obj.removeEventListener)) {
346                     obj.removeEventListener(type, owner['x_internal' + type][i], false);
347                 }
348 
349                 // IE
350                 if (Type.exists(obj) && Type.exists(obj.detachEvent)) {
351                     obj.detachEvent('on' + type, owner['x_internal' + type][i]);
352                 }
353             } catch (e) {
354                 JXG.debug('event not registered in browser: (' + type + ' -- ' + fn + ')');
355             }
356 
357             owner['x_internal' + type].splice(i, 1);
358         },
359 
360         /**
361          * Removes all events of the given type from a given DOM node; Use with caution and do not use it on a container div
362          * of a {@link JXG.Board} because this might corrupt the event handling system.
363          * @param {Object} obj Reference to a DOM node.
364          * @param {String} type The event to catch, without leading 'on', e.g. 'mousemove' instead of 'onmousemove'.
365          * @param {Object} owner The scope in which the event trigger is called.
366          */
367         removeAllEvents: function (obj, type, owner) {
368             var i, len;
369             if (owner['x_internal' + type]) {
370                 len = owner['x_internal' + type].length;
371 
372                 for (i = len - 1; i >= 0; i--) {
373                     JXG.removeEvent(obj, type, owner['x_internal' + type][i].origin, owner);
374                 }
375 
376                 if (owner['x_internal' + type].length > 0) {
377                     JXG.debug('removeAllEvents: Not all events could be removed.');
378                 }
379             }
380         },
381 
382         /**
383          * Cross browser mouse / touch coordinates retrieval relative to the board's top left corner.
384          * @param {Object} [e] The browsers event object. If omitted, <tt>window.event</tt> will be used.
385          * @param {Number} [index] If <tt>e</tt> is a touch event, this provides the index of the touch coordinates, i.e. it determines which finger.
386          * @returns {Array} Contains the position as x,y-coordinates in the first resp. second component.
387          */
388         getPosition: function (e, index) {
389             var i, len, evtTouches,
390                 posx = 0,
391                 posy = 0;
392 
393             if (!e) {
394                 e = window.event;
395             }
396 
397             evtTouches = e[JXG.touchProperty];
398 
399             if (Type.exists(index)) {
400                 if (index === -1) {
401                     len = evtTouches.length;
402 
403                     for (i = 0; i < len; i++) {
404                         if (evtTouches[i]) {
405                             e = evtTouches[i];
406                             break;
407                         }
408                     }
409                 } else {
410                     e = evtTouches[index];
411                 }
412             }
413 
414             if (e.pageX || e.pageY) {
415                 posx = e.pageX;
416                 posy = e.pageY;
417             } else if (e.clientX || e.clientY) {
418                 posx = e.clientX + document.body.scrollLeft + document.documentElement.scrollLeft;
419                 posy = e.clientY + document.body.scrollTop + document.documentElement.scrollTop;
420             }
421 
422             return [posx, posy];
423         },
424 
425         /**
426          * Calculates recursively the offset of the DOM element in which the board is stored.
427          * @param {Object} obj A DOM element
428          * @returns {Array} An array with the elements left and top offset.
429          */
430         getOffset: function (obj) {
431             var cPos,
432                 o = obj,
433                 o2 = obj,
434                 l = o.offsetLeft - o.scrollLeft,
435                 t = o.offsetTop - o.scrollTop;
436 
437             cPos = this.getCSSTransform([l, t], o);
438             l = cPos[0];
439             t = cPos[1];
440 
441             /*
442              * In Mozilla and Webkit: offsetParent seems to jump at least to the next iframe,
443              * if not to the body. In IE and if we are in an position:absolute environment
444              * offsetParent walks up the DOM hierarchy.
445              * In order to walk up the DOM hierarchy also in Mozilla and Webkit
446              * we need the parentNode steps.
447              */
448             o = o.offsetParent;
449             while (o) {
450                 l += o.offsetLeft;
451                 t += o.offsetTop;
452 
453                 if (o.offsetParent) {
454                     l += o.clientLeft - o.scrollLeft;
455                     t += o.clientTop - o.scrollTop;
456                 }
457 
458                 cPos = this.getCSSTransform([l, t], o);
459                 l = cPos[0];
460                 t = cPos[1];
461 
462                 o2 = o2.parentNode;
463 
464                 while (o2 !== o) {
465                     l += o2.clientLeft - o2.scrollLeft;
466                     t += o2.clientTop - o2.scrollTop;
467 
468                     cPos = this.getCSSTransform([l, t], o2);
469                     l = cPos[0];
470                     t = cPos[1];
471 
472                     o2 = o2.parentNode;
473                 }
474                 o = o.offsetParent;
475             }
476             return [l, t];
477         },
478 
479         /**
480          * Access CSS style sheets.
481          * @param {Object} obj A DOM element
482          * @param {String} stylename The CSS property to read.
483          * @returns The value of the CSS property and <tt>undefined</tt> if it is not set.
484          */
485         getStyle: function (obj, stylename) {
486             var r;
487 
488             // Non-IE
489             if (window.getComputedStyle) {
490                 r = document.defaultView.getComputedStyle(obj, null).getPropertyValue(stylename);
491                 // IE
492             } else if (obj.currentStyle && JXG.ieVersion >= 9) {
493                 r = obj.currentStyle[stylename];
494             } else {
495                 if (obj.style) {
496                     // make stylename lower camelcase
497                     stylename = stylename.replace(/-([a-z]|[0-9])/ig, function (all, letter) {
498                         return letter.toUpperCase();
499                     });
500                     r = obj.style[stylename];
501                 }
502             }
503 
504             return r;
505         },
506 
507         /**
508          * Reads css style sheets of a given element. This method is a getStyle wrapper and
509          * defaults the read value to <tt>0</tt> if it can't be parsed as an integer value.
510          * @param {DOMElement} el
511          * @param {string} css
512          * @returns {number}
513          */
514         getProp: function (el, css) {
515             var n = parseInt(this.getStyle(el, css), 10);
516             return isNaN(n) ? 0 : n;
517         },
518 
519         /**
520          * Correct position of upper left corner in case of
521          * a CSS transformation. Here, only translations are
522          * extracted. All scaling transformations are corrected
523          * in {@link JXG.Board#getMousePosition}.
524          * @param {Array} cPos Previously determined position
525          * @param {Object} obj A DOM element
526          * @returns {Array} The corrected position.
527          */
528         getCSSTransform: function (cPos, obj) {
529             var i, j, str, arrStr, start, len, len2, arr,
530                 t = ['transform', 'webkitTransform', 'MozTransform', 'msTransform', 'oTransform'];
531 
532             // Take the first transformation matrix
533             len = t.length;
534 
535             for (i = 0, str = ''; i < len; i++) {
536                 if (Type.exists(obj.style[t[i]])) {
537                     str = obj.style[t[i]];
538                     break;
539                 }
540             }
541 
542             /**
543              * Extract the coordinates and apply the transformation
544              * to cPos
545              */
546             if (str !== '') {
547                 start = str.indexOf('(');
548 
549                 if (start > 0) {
550                     len = str.length;
551                     arrStr = str.substring(start + 1, len - 1);
552                     arr = arrStr.split(',');
553 
554                     for (j = 0, len2 = arr.length; j < len2; j++) {
555                         arr[j] = parseFloat(arr[j]);
556                     }
557 
558                     if (str.indexOf('matrix') === 0) {
559                         cPos[0] += arr[4];
560                         cPos[1] += arr[5];
561                     } else if (str.indexOf('translateX') === 0) {
562                         cPos[0] += arr[0];
563                     } else if (str.indexOf('translateY') === 0) {
564                         cPos[1] += arr[0];
565                     } else if (str.indexOf('translate') === 0) {
566                         cPos[0] += arr[0];
567                         cPos[1] += arr[1];
568                     }
569                 }
570             }
571             return cPos;
572         },
573 
574         /**
575          * Scaling CSS transformations applied to the div element containing the JSXGraph constructions
576          * are determined. Not implemented are 'rotate', 'skew', 'skewX', 'skewY'.
577          * @returns {Array} 3x3 transformation matrix. See {@link JXG.Board#updateCSSTransforms}.
578          */
579         getCSSTransformMatrix: function (obj) {
580             var i, j, str, arrstr, start, len, len2, arr,
581                 t = ['transform', 'webkitTransform', 'MozTransform', 'msTransform', 'oTransform'],
582                 mat = [[1, 0, 0],
583                     [0, 1, 0],
584                     [0, 0, 1]];
585 
586             // Take the first transformation matrix
587             len = t.length;
588             for (i = 0, str = ''; i < len; i++) {
589                 if (Type.exists(obj.style[t[i]])) {
590                     str = obj.style[t[i]];
591                     break;
592                 }
593             }
594 
595             if (str !== '') {
596                 start = str.indexOf('(');
597 
598                 if (start > 0) {
599                     len = str.length;
600                     arrstr = str.substring(start + 1, len - 1);
601                     arr = arrstr.split(',');
602 
603                     for (j = 0, len2 = arr.length; j < len2; j++) {
604                         arr[j] = parseFloat(arr[j]);
605                     }
606 
607                     if (str.indexOf('matrix') === 0) {
608                         mat = [[1, 0, 0],
609                             [0, arr[0], arr[1]],
610                             [0, arr[2], arr[3]]];
611                         // Missing are rotate, skew, skewX, skewY
612                     } else if (str.indexOf('scaleX') === 0) {
613                         mat[1][1] = arr[0];
614                     } else if (str.indexOf('scaleY') === 0) {
615                         mat[2][2] = arr[0];
616                     } else if (str.indexOf('scale') === 0) {
617                         mat[1][1] = arr[0];
618                         mat[2][2] = arr[1];
619                     }
620                 }
621             }
622             return mat;
623         },
624 
625         /**
626          * Process data in timed chunks. Data which takes long to process, either because it is such
627          * a huge amount of data or the processing takes some time, causes warnings in browsers about
628          * irresponsive scripts. To prevent these warnings, the processing is split into smaller pieces
629          * called chunks which will be processed in serial order.
630          * Copyright 2009 Nicholas C. Zakas. All rights reserved. MIT Licensed
631          * @param {Array} items to do
632          * @param {Function} process Function that is applied for every array item
633          * @param {Object} context The scope of function process
634          * @param {Function} callback This function is called after the last array element has been processed.
635          */
636         timedChunk: function (items, process, context, callback) {
637             //create a clone of the original
638             var todo = items.concat(),
639                 timerFun = function () {
640                     var start = +new Date();
641 
642                     do {
643                         process.call(context, todo.shift());
644                     } while (todo.length > 0 && (+new Date() - start < 300));
645 
646                     if (todo.length > 0) {
647                         window.setTimeout(timerFun, 1);
648                     } else {
649                         callback(items);
650                     }
651                 };
652 
653             window.setTimeout(timerFun, 1);
654         }
655     });
656 
657     return JXG;
658 });
659