1 /*
  2     Copyright 2008-2016
  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, hasCanvas = false;
 89 
 90             if (this.isNode()) {
 91                 try {
 92                     c = (typeof module === 'object' ? module.require('canvas') : require('canvas'));
 93                     hasCanvas = !!c;
 94                 } catch (err) { }
 95             }
 96 
 97             return hasCanvas || (this.isBrowser && !!document.createElement('canvas').getContext);
 98         },
 99 
100         /**
101          * True, if run inside a node.js environment.
102          * @returns {Boolean}
103          */
104         isNode: function () {
105             // this is not a 100% sure but should be valid in most cases
106 
107                 // we are not inside a browser
108             return !this.isBrowser && (
109                 // there is a module object (plain node, no requirejs)
110                 (typeof module === 'object' && !!module.exports) ||
111                 // there is a global object and requirejs is loaded
112                 (typeof global === 'object' && global.requirejsVars && !global.requirejsVars.isBrowser)
113             );
114         },
115 
116         /**
117          * True if run inside a webworker environment.
118          * @returns {Boolean}
119          */
120         isWebWorker: function () {
121             return !this.isBrowser && (typeof self === 'object' && typeof self.postMessage === 'function');
122         },
123 
124         /**
125          * Checks if the environments supports the W3C Pointer Events API {@link http://www.w3.org/Submission/pointer-events/}
126          * @returns {Boolean}
127          */
128         supportsPointerEvents: function () {
129             return JXG.isBrowser && window.navigator && (window.navigator.msPointerEnabled || window.navigator.pointerEnabled);
130         },
131 
132         /**
133          * Determine if the current browser supports touch events
134          * @returns {Boolean} True, if the browser supports touch events.
135          */
136         isTouchDevice: function () {
137             return this.isBrowser && window.ontouchstart !== undefined;
138         },
139 
140         /**
141          * Detects if the user is using an Android powered device.
142          * @returns {Boolean}
143          */
144         isAndroid: function () {
145             return Type.exists(navigator) && navigator.userAgent.toLowerCase().indexOf('android') > -1;
146         },
147 
148         /**
149          * Detects if the user is using the default Webkit browser on an Android powered device.
150          * @returns {Boolean}
151          */
152         isWebkitAndroid: function () {
153             return this.isAndroid() && navigator.userAgent.indexOf(' AppleWebKit/') > -1;
154         },
155 
156         /**
157          * Detects if the user is using a Apple iPad / iPhone.
158          * @returns {Boolean}
159          */
160         isApple: function () {
161             return Type.exists(navigator) && (navigator.userAgent.indexOf('iPad') > -1 || navigator.userAgent.indexOf('iPhone') > -1);
162         },
163 
164         /**
165          * Detects if the user is using Safari on an Apple device.
166          * @returns {Boolean}
167          */
168         isWebkitApple: function () {
169             return this.isApple() && (navigator.userAgent.search(/Mobile\/[0-9A-Za-z\.]*Safari/) > -1);
170         },
171 
172         /**
173          * Returns true if the run inside a Windows 8 "Metro" App.
174          * @returns {Boolean}
175          */
176         isMetroApp: function () {
177             return typeof window === 'object' && window.clientInformation && window.clientInformation.appVersion && window.clientInformation.appVersion.indexOf('MSAppHost') > -1;
178         },
179 
180         /**
181          * Detects if the user is using a Mozilla browser
182          * @returns {Boolean}
183          */
184         isMozilla: function () {
185             return Type.exists(navigator) &&
186                 navigator.userAgent.toLowerCase().indexOf('mozilla') > -1 &&
187                 navigator.userAgent.toLowerCase().indexOf('apple') === -1;
188         },
189 
190         /**
191          * Detects if the user is using a firefoxOS powered device.
192          * @returns {Boolean}
193          */
194         isFirefoxOS: function () {
195             return Type.exists(navigator) &&
196                 navigator.userAgent.toLowerCase().indexOf('android') === -1 &&
197                 navigator.userAgent.toLowerCase().indexOf('apple') === -1 &&
198                 navigator.userAgent.toLowerCase().indexOf('mobile') > -1 &&
199                 navigator.userAgent.toLowerCase().indexOf('mozilla') > -1;
200         },
201 
202         /**
203          * Internet Explorer version. Works only for IE > 4.
204          * @type Number
205          */
206         ieVersion: (function () {
207             var undef, div, all,
208                 v = 3;
209 
210             if (typeof document !== 'object') {
211                 return 0;
212             }
213 
214             div = document.createElement('div');
215             all = div.getElementsByTagName('i');
216 
217             do {
218                 div.innerHTML = '<!--[if gt IE ' + (++v) + ']><' + 'i><' + '/i><![endif]-->';
219             } while (all[0]);
220 
221             return v > 4 ? v : undef;
222 
223         }()),
224 
225         /**
226          * Reads the width and height of an HTML element.
227          * @param {String} elementId The HTML id of an HTML DOM node.
228          * @returns {Object} An object with the two properties width and height.
229          */
230         getDimensions: function (elementId, doc) {
231             var element, display, els, originalVisibility, originalPosition,
232                 originalDisplay, originalWidth, originalHeight, style,
233                 pixelDimRegExp = /\d+(\.\d*)?px/;
234 
235             if (!JXG.isBrowser || elementId === null) {
236                 return {
237                     width: 500,
238                     height: 500
239                 };
240             }
241 
242             doc = doc || document;
243             // Borrowed from prototype.js
244             element = doc.getElementById(elementId);
245             if (!Type.exists(element)) {
246                 throw new Error("\nJSXGraph: HTML container element '" + elementId + "' not found.");
247             }
248 
249             display = element.style.display;
250 
251             // Work around a bug in Safari
252             if (display !== 'none' && display !== null) {
253                 if (element.clientWidth > 0 && element.clientHeight > 0) {
254                     return {width: element.clientWidth, height: element.clientHeight};
255                 }
256 
257                 // a parent might be set to display:none; try reading them from styles
258                 style = window.getComputedStyle ? window.getComputedStyle(element) : element.style;
259                 return {
260                     width: pixelDimRegExp.test(style.width) ? parseFloat(style.width) : 0,
261                     height: pixelDimRegExp.test(style.height) ? parseFloat(style.height) : 0
262                 };
263             }
264 
265             // All *Width and *Height properties give 0 on elements with display set to none,
266             // hence we show the element temporarily
267             els = element.style;
268 
269             // save style
270             originalVisibility = els.visibility;
271             originalPosition = els.position;
272             originalDisplay = els.display;
273 
274             // show element
275             els.visibility = 'hidden';
276             els.position = 'absolute';
277             els.display = 'block';
278 
279             // read the dimension
280             originalWidth = element.clientWidth;
281             originalHeight = element.clientHeight;
282 
283             // restore original css values
284             els.display = originalDisplay;
285             els.position = originalPosition;
286             els.visibility = originalVisibility;
287 
288             return {
289                 width: originalWidth,
290                 height: originalHeight
291             };
292         },
293 
294         /**
295          * Adds an event listener to a DOM element.
296          * @param {Object} obj Reference to a DOM node.
297          * @param {String} type The event to catch, without leading 'on', e.g. 'mousemove' instead of 'onmousemove'.
298          * @param {Function} fn The function to call when the event is triggered.
299          * @param {Object} owner The scope in which the event trigger is called.
300          */
301         addEvent: function (obj, type, fn, owner) {
302             var el = function () {
303                 return fn.apply(owner, arguments);
304             };
305 
306             el.origin = fn;
307             owner['x_internal' + type] = owner['x_internal' + type] || [];
308             owner['x_internal' + type].push(el);
309 
310             // Non-IE browser
311             if (Type.exists(obj) && Type.exists(obj.addEventListener)) {
312                 obj.addEventListener(type, el, false);
313             }
314 
315             // IE
316             if (Type.exists(obj) && Type.exists(obj.attachEvent)) {
317                 obj.attachEvent('on' + type, el);
318             }
319         },
320 
321         /**
322          * Removes an event listener from a DOM element.
323          * @param {Object} obj Reference to a DOM node.
324          * @param {String} type The event to catch, without leading 'on', e.g. 'mousemove' instead of 'onmousemove'.
325          * @param {Function} fn The function to call when the event is triggered.
326          * @param {Object} owner The scope in which the event trigger is called.
327          */
328         removeEvent: function (obj, type, fn, owner) {
329             var i;
330 
331             if (!Type.exists(owner)) {
332                 JXG.debug('no such owner');
333                 return;
334             }
335 
336             if (!Type.exists(owner['x_internal' + type])) {
337                 JXG.debug('no such type: ' + type);
338                 return;
339             }
340 
341             if (!Type.isArray(owner['x_internal' + type])) {
342                 JXG.debug('owner[x_internal + ' + type + '] is not an array');
343                 return;
344             }
345 
346             i = Type.indexOf(owner['x_internal' + type], fn, 'origin');
347 
348             if (i === -1) {
349                 JXG.debug('no such event function in internal list: ' + fn);
350                 return;
351             }
352 
353             try {
354                 // Non-IE browser
355                 if (Type.exists(obj) && Type.exists(obj.removeEventListener)) {
356                     obj.removeEventListener(type, owner['x_internal' + type][i], false);
357                 }
358 
359                 // IE
360                 if (Type.exists(obj) && Type.exists(obj.detachEvent)) {
361                     obj.detachEvent('on' + type, owner['x_internal' + type][i]);
362                 }
363             } catch (e) {
364                 JXG.debug('event not registered in browser: (' + type + ' -- ' + fn + ')');
365             }
366 
367             owner['x_internal' + type].splice(i, 1);
368         },
369 
370         /**
371          * Removes all events of the given type from a given DOM node; Use with caution and do not use it on a container div
372          * of a {@link JXG.Board} because this might corrupt the event handling system.
373          * @param {Object} obj Reference to a DOM node.
374          * @param {String} type The event to catch, without leading 'on', e.g. 'mousemove' instead of 'onmousemove'.
375          * @param {Object} owner The scope in which the event trigger is called.
376          */
377         removeAllEvents: function (obj, type, owner) {
378             var i, len;
379             if (owner['x_internal' + type]) {
380                 len = owner['x_internal' + type].length;
381 
382                 for (i = len - 1; i >= 0; i--) {
383                     JXG.removeEvent(obj, type, owner['x_internal' + type][i].origin, owner);
384                 }
385 
386                 if (owner['x_internal' + type].length > 0) {
387                     JXG.debug('removeAllEvents: Not all events could be removed.');
388                 }
389             }
390         },
391 
392         /**
393          * Cross browser mouse / touch coordinates retrieval relative to the board's top left corner.
394          * @param {Object} [e] The browsers event object. If omitted, <tt>window.event</tt> will be used.
395          * @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.
396          * @param {Object} [doc] The document object.
397          * @returns {Array} Contains the position as x,y-coordinates in the first resp. second component.
398          */
399         getPosition: function (e, index, doc) {
400             var i, len, evtTouches,
401                 posx = 0,
402                 posy = 0;
403 
404             if (!e) {
405                 e = window.event;
406             }
407 
408             doc = doc || document;
409             evtTouches = e[JXG.touchProperty];
410 
411             // touchend events have their position in "changedTouches"
412             if (Type.exists(evtTouches) && evtTouches.length === 0) {
413                 evtTouches = e.changedTouches;
414             }
415 
416             if (Type.exists(index) && Type.exists(evtTouches)) {
417                 if (index === -1) {
418                     len = evtTouches.length;
419 
420                     for (i = 0; i < len; i++) {
421                         if (evtTouches[i]) {
422                             e = evtTouches[i];
423                             break;
424                         }
425                     }
426 
427                 } else {
428                     e = evtTouches[index];
429                 }
430             }
431 
432             // Scrolling is ignored.
433             // e.clientX is supported since IE6
434             if (e.clientX) {
435                 posx = e.clientX;
436                 posy = e.clientY;
437             }
438 
439             return [posx, posy];
440         },
441 
442         /**
443          * Calculates recursively the offset of the DOM element in which the board is stored.
444          * @param {Object} obj A DOM element
445          * @returns {Array} An array with the elements left and top offset.
446          */
447         getOffset: function (obj) {
448             var cPos,
449                 o = obj,
450                 o2 = obj,
451                 l = o.offsetLeft - o.scrollLeft,
452                 t = o.offsetTop - o.scrollTop;
453 
454             cPos = this.getCSSTransform([l, t], o);
455             l = cPos[0];
456             t = cPos[1];
457 
458             /*
459              * In Mozilla and Webkit: offsetParent seems to jump at least to the next iframe,
460              * if not to the body. In IE and if we are in an position:absolute environment
461              * offsetParent walks up the DOM hierarchy.
462              * In order to walk up the DOM hierarchy also in Mozilla and Webkit
463              * we need the parentNode steps.
464              */
465             o = o.offsetParent;
466             while (o) {
467                 l += o.offsetLeft;
468                 t += o.offsetTop;
469 
470                 if (o.offsetParent) {
471                     l += o.clientLeft - o.scrollLeft;
472                     t += o.clientTop - o.scrollTop;
473                 }
474 
475                 cPos = this.getCSSTransform([l, t], o);
476                 l = cPos[0];
477                 t = cPos[1];
478 
479                 o2 = o2.parentNode;
480 
481                 while (o2 !== o) {
482                     l += o2.clientLeft - o2.scrollLeft;
483                     t += o2.clientTop - o2.scrollTop;
484 
485                     cPos = this.getCSSTransform([l, t], o2);
486                     l = cPos[0];
487                     t = cPos[1];
488 
489                     o2 = o2.parentNode;
490                 }
491                 o = o.offsetParent;
492             }
493             return [l, t];
494         },
495 
496         /**
497          * Access CSS style sheets.
498          * @param {Object} obj A DOM element
499          * @param {String} stylename The CSS property to read.
500          * @returns The value of the CSS property and <tt>undefined</tt> if it is not set.
501          */
502         getStyle: function (obj, stylename) {
503             var r,
504                 doc = obj.ownerDocument;
505 
506             // Non-IE
507             if (doc.defaultView && doc.defaultView.getComputedStyle) {
508                 r = doc.defaultView.getComputedStyle(obj, null).getPropertyValue(stylename);
509             // IE
510             } else if (obj.currentStyle && JXG.ieVersion >= 9) {
511                 r = obj.currentStyle[stylename];
512             } else {
513                 if (obj.style) {
514                     // make stylename lower camelcase
515                     stylename = stylename.replace(/-([a-z]|[0-9])/ig, function (all, letter) {
516                         return letter.toUpperCase();
517                     });
518                     r = obj.style[stylename];
519                 }
520             }
521 
522             return r;
523         },
524 
525         /**
526          * Reads css style sheets of a given element. This method is a getStyle wrapper and
527          * defaults the read value to <tt>0</tt> if it can't be parsed as an integer value.
528          * @param {DOMElement} el
529          * @param {string} css
530          * @returns {number}
531          */
532         getProp: function (el, css) {
533             var n = parseInt(this.getStyle(el, css), 10);
534             return isNaN(n) ? 0 : n;
535         },
536 
537         /**
538          * Correct position of upper left corner in case of
539          * a CSS transformation. Here, only translations are
540          * extracted. All scaling transformations are corrected
541          * in {@link JXG.Board#getMousePosition}.
542          * @param {Array} cPos Previously determined position
543          * @param {Object} obj A DOM element
544          * @returns {Array} The corrected position.
545          */
546         getCSSTransform: function (cPos, obj) {
547             var i, j, str, arrStr, start, len, len2, arr,
548                 t = ['transform', 'webkitTransform', 'MozTransform', 'msTransform', 'oTransform'];
549 
550             // Take the first transformation matrix
551             len = t.length;
552 
553             for (i = 0, str = ''; i < len; i++) {
554                 if (Type.exists(obj.style[t[i]])) {
555                     str = obj.style[t[i]];
556                     break;
557                 }
558             }
559 
560             /**
561              * Extract the coordinates and apply the transformation
562              * to cPos
563              */
564             if (str !== '') {
565                 start = str.indexOf('(');
566 
567                 if (start > 0) {
568                     len = str.length;
569                     arrStr = str.substring(start + 1, len - 1);
570                     arr = arrStr.split(',');
571 
572                     for (j = 0, len2 = arr.length; j < len2; j++) {
573                         arr[j] = parseFloat(arr[j]);
574                     }
575 
576                     if (str.indexOf('matrix') === 0) {
577                         cPos[0] += arr[4];
578                         cPos[1] += arr[5];
579                     } else if (str.indexOf('translateX') === 0) {
580                         cPos[0] += arr[0];
581                     } else if (str.indexOf('translateY') === 0) {
582                         cPos[1] += arr[0];
583                     } else if (str.indexOf('translate') === 0) {
584                         cPos[0] += arr[0];
585                         cPos[1] += arr[1];
586                     }
587                 }
588             }
589             return cPos;
590         },
591 
592         /**
593          * Scaling CSS transformations applied to the div element containing the JSXGraph constructions
594          * are determined. In IE prior to 9, 'rotate', 'skew', 'skewX', 'skewY' are not supported.
595          * @returns {Array} 3x3 transformation matrix without translation part. See {@link JXG.Board#updateCSSTransforms}.
596          */
597         getCSSTransformMatrix: function (obj) {
598             var i, j, str, arrstr, start, len, len2, arr,
599                 st, tr,
600                 doc = obj.ownerDocument,
601                 t = ['transform', 'webkitTransform', 'MozTransform', 'msTransform', 'oTransform'],
602                 mat = [[1, 0, 0],
603                     [0, 1, 0],
604                     [0, 0, 1]];
605 
606             // This should work on all browsers except IE 6-8
607             if (doc.defaultView && doc.defaultView.getComputedStyle) {
608                 st = doc.defaultView.getComputedStyle(obj, null);
609                 str = st.getPropertyValue("-webkit-transform") ||
610                      st.getPropertyValue("-moz-transform") ||
611                      st.getPropertyValue("-ms-transform") ||
612                      st.getPropertyValue("-o-transform") ||
613                      st.getPropertyValue("transform");
614             } else {
615                 // Take the first transformation matrix
616                 len = t.length;
617                 for (i = 0, str = ''; i < len; i++) {
618                     if (Type.exists(obj.style[t[i]])) {
619                         str = obj.style[t[i]];
620                         break;
621                     }
622                 }
623             }
624 
625             if (str !== '') {
626                 start = str.indexOf('(');
627 
628                 if (start > 0) {
629                     len = str.length;
630                     arrstr = str.substring(start + 1, len - 1);
631                     arr = arrstr.split(',');
632 
633                     for (j = 0, len2 = arr.length; j < len2; j++) {
634                         arr[j] = parseFloat(arr[j]);
635                     }
636 
637                     if (str.indexOf('matrix') === 0) {
638                         mat = [[1, 0, 0],
639                             [0, arr[0], arr[1]],
640                             [0, arr[2], arr[3]]];
641                     } else if (str.indexOf('scaleX') === 0) {
642                         mat[1][1] = arr[0];
643                     } else if (str.indexOf('scaleY') === 0) {
644                         mat[2][2] = arr[0];
645                     } else if (str.indexOf('scale') === 0) {
646                         mat[1][1] = arr[0];
647                         mat[2][2] = arr[1];
648                     }
649                 }
650             }
651             return mat;
652         },
653 
654         /**
655          * Process data in timed chunks. Data which takes long to process, either because it is such
656          * a huge amount of data or the processing takes some time, causes warnings in browsers about
657          * irresponsive scripts. To prevent these warnings, the processing is split into smaller pieces
658          * called chunks which will be processed in serial order.
659          * Copyright 2009 Nicholas C. Zakas. All rights reserved. MIT Licensed
660          * @param {Array} items to do
661          * @param {Function} process Function that is applied for every array item
662          * @param {Object} context The scope of function process
663          * @param {Function} callback This function is called after the last array element has been processed.
664          */
665         timedChunk: function (items, process, context, callback) {
666             //create a clone of the original
667             var todo = items.concat(),
668                 timerFun = function () {
669                     var start = +new Date();
670 
671                     do {
672                         process.call(context, todo.shift());
673                     } while (todo.length > 0 && (+new Date() - start < 300));
674 
675                     if (todo.length > 0) {
676                         window.setTimeout(timerFun, 1);
677                     } else {
678                         callback(items);
679                     }
680                 };
681 
682             window.setTimeout(timerFun, 1);
683         }
684     });
685 
686     return JXG;
687 });
688