window.js

define(["./_base/lang", "./sniff", "./_base/window", "./dom", "./dom-geometry", "./dom-style", "./dom-construct"],
	function(lang, has, baseWindow, dom, geom, style, domConstruct){

	// feature detection
	/* not needed but included here for future reference
	has.add("rtl-innerVerticalScrollBar-on-left", function(win, doc){
		var	body = baseWindow.body(doc),
			scrollable = domConstruct.create('div', {
				style: {overflow:'scroll', overflowX:'hidden', direction:'rtl', visibility:'hidden', position:'absolute', left:'0', width:'64px', height:'64px'}
			}, body, "last"),
			center = domConstruct.create('center', {
				style: {overflow:'hidden', direction:'ltr'}
			}, scrollable, "last"),
			inner = domConstruct.create('div', {
				style: {overflow:'visible', display:'inline' }
			}, center, "last");
		inner.innerHTML=" ";
		var midPoint = Math.max(inner.offsetLeft, geom.position(inner).x);
		var ret = midPoint >= 32;
		center.removeChild(inner);
		scrollable.removeChild(center);
		body.removeChild(scrollable);
		return ret;
	});
	*/
	has.add("rtl-adjust-position-for-verticalScrollBar", function(win, doc){
		var	body = baseWindow.body(doc),
			scrollable = domConstruct.create('div', {
				style: {overflow:'scroll', overflowX:'visible', direction:'rtl', visibility:'hidden', position:'absolute', left:'0', top:'0', width:'64px', height:'64px'}
			}, body, "last"),
			div = domConstruct.create('div', {
				style: {overflow:'hidden', direction:'ltr'}
			}, scrollable, "last"),
			ret = geom.position(div).x != 0;
		scrollable.removeChild(div);
		body.removeChild(scrollable);
		return ret;
	});

	has.add("position-fixed-support", function(win, doc){
		// IE6, IE7+quirks, and some older mobile browsers don't support position:fixed
		var	body = baseWindow.body(doc),
			outer = domConstruct.create('span', {
				style: {visibility:'hidden', position:'fixed', left:'1px', top:'1px'}
			}, body, "last"),
			inner = domConstruct.create('span', {
				style: {position:'fixed', left:'0', top:'0'}
			}, outer, "last"),
			ret = geom.position(inner).x != geom.position(outer).x;
		outer.removeChild(inner);
		body.removeChild(outer);
		return ret;
	});

	// module:
	//		dojo/window

	var window = {
		// summary:
		//		TODOC

		getBox: function(/*Document?*/ doc){
			// summary:
			//		Returns the dimensions and scroll position of the viewable area of a browser window

			doc = doc || baseWindow.doc;

			var
				scrollRoot = (doc.compatMode == 'BackCompat') ? baseWindow.body(doc) : doc.documentElement,
				// get scroll position
				scroll = geom.docScroll(doc), // scrollRoot.scrollTop/Left should work
				w, h;

			if(has("touch")){ // if(scrollbars not supported)
				var uiWindow = window.get(doc);   // use UI window, not dojo.global window
				// on mobile, scrollRoot.clientHeight <= uiWindow.innerHeight <= scrollRoot.offsetHeight, return uiWindow.innerHeight
				w = uiWindow.innerWidth || scrollRoot.clientWidth; // || scrollRoot.clientXXX probably never evaluated
				h = uiWindow.innerHeight || scrollRoot.clientHeight;
			}else{
				// on desktops, scrollRoot.clientHeight <= scrollRoot.offsetHeight <= uiWindow.innerHeight, return scrollRoot.clientHeight
				// uiWindow.innerWidth/Height includes the scrollbar and cannot be used
				w = scrollRoot.clientWidth;
				h = scrollRoot.clientHeight;
			}
			return {
				l: scroll.x,
				t: scroll.y,
				w: w,
				h: h
			};
		},

		get: function(/*Document*/ doc){
			// summary:
			//		Get window object associated with document doc.
			// doc:
			//		The document to get the associated window for.

			// In some IE versions (at least 6.0), document.parentWindow does not return a
			// reference to the real window object (maybe a copy), so we must fix it as well
			// We use IE specific execScript to attach the real window reference to
			// document._parentWindow for later use
			if(has("ie") && window !== document.parentWindow){
				/*
				In IE 6, only the variable "window" can be used to connect events (others
				may be only copies).
				*/
				doc.parentWindow.execScript("document._parentWindow = window;", "Javascript");
				//to prevent memory leak, unset it after use
				//another possibility is to add an onUnload handler which seems overkill to me (liucougar)
				var win = doc._parentWindow;
				doc._parentWindow = null;
				return win;	//	Window
			}

			return doc.parentWindow || doc.defaultView;	//	Window
		},

		scrollIntoView: function(/*DomNode*/ node, /*Object?*/ pos){
			// summary:
			//		Scroll the passed node into view using minimal movement, if it is not already.

			// Don't rely on node.scrollIntoView working just because the function is there since
			// it forces the node to the page's bottom or top (and left or right in IE) without consideration for the minimal movement.
			// WebKit's node.scrollIntoViewIfNeeded doesn't work either for inner scrollbars in right-to-left mode
			// and when there's a fixed position scrollable element

			try{ // catch unexpected/unrecreatable errors (#7808) since we can recover using a semi-acceptable native method
				node = dom.byId(node);
				var	doc = node.ownerDocument || baseWindow.doc,	// TODO: why baseWindow.doc?  Isn't node.ownerDocument always defined?
					body = baseWindow.body(doc),
					html = doc.documentElement || body.parentNode,
					isIE = has("ie") || has("trident"),
					isWK = has("webkit");
				// if an untested browser, then use the native method
				if(node == body || node == html){ return; }
				if(!(has("mozilla") || isIE || isWK || has("opera") || has("trident") || has("edge"))
						&& ("scrollIntoView" in node)){
					node.scrollIntoView(false); // short-circuit to native if possible
					return;
				}
				var	backCompat = doc.compatMode == 'BackCompat',
					rootWidth = Math.min(body.clientWidth || html.clientWidth, html.clientWidth || body.clientWidth),
					rootHeight = Math.min(body.clientHeight || html.clientHeight, html.clientHeight || body.clientHeight),
					scrollRoot = (isWK || backCompat) ? body : html,
					nodePos = pos || geom.position(node),
					el = node.parentNode,
					isFixed = function(el){
						return (isIE <= 6 || (isIE == 7 && backCompat))
							? false
							: (has("position-fixed-support") && (style.get(el, 'position').toLowerCase() == "fixed"));
					},
					self = this,
					scrollElementBy = function(el, x, y){
						if(el.tagName == "BODY" || el.tagName == "HTML"){
							self.get(el.ownerDocument).scrollBy(x, y);
						}else{
							x && (el.scrollLeft += x);
							y && (el.scrollTop += y);
						}
					};
				if(isFixed(node)){ return; } // nothing to do
				while(el){
					if(el == body){ el = scrollRoot; }
					var	elPos = geom.position(el),
						fixedPos = isFixed(el),
						rtl = style.getComputedStyle(el).direction.toLowerCase() == "rtl";

					if(el == scrollRoot){
						elPos.w = rootWidth; elPos.h = rootHeight;
						if(scrollRoot == html && (isIE || has("trident")) && rtl){
							elPos.x += scrollRoot.offsetWidth-elPos.w;// IE workaround where scrollbar causes negative x
						}
						elPos.x = 0;
						elPos.y = 0;
					}else{
						var pb = geom.getPadBorderExtents(el);
						elPos.w -= pb.w; elPos.h -= pb.h; elPos.x += pb.l; elPos.y += pb.t;
						var clientSize = el.clientWidth,
							scrollBarSize = elPos.w - clientSize;
						if(clientSize > 0 && scrollBarSize > 0){
							if(rtl && has("rtl-adjust-position-for-verticalScrollBar")){
								elPos.x += scrollBarSize;
							}
							elPos.w = clientSize;
						}
						clientSize = el.clientHeight;
						scrollBarSize = elPos.h - clientSize;
						if(clientSize > 0 && scrollBarSize > 0){
							elPos.h = clientSize;
						}
					}
					if(fixedPos){ // bounded by viewport, not parents
						if(elPos.y < 0){
							elPos.h += elPos.y; elPos.y = 0;
						}
						if(elPos.x < 0){
							elPos.w += elPos.x; elPos.x = 0;
						}
						if(elPos.y + elPos.h > rootHeight){
							elPos.h = rootHeight - elPos.y;
						}
						if(elPos.x + elPos.w > rootWidth){
							elPos.w = rootWidth - elPos.x;
						}
					}
					// calculate overflow in all 4 directions
					var	l = nodePos.x - elPos.x, // beyond left: < 0
//						t = nodePos.y - Math.max(elPos.y, 0), // beyond top: < 0
						t = nodePos.y - elPos.y, // beyond top: < 0
						r = l + nodePos.w - elPos.w, // beyond right: > 0
						bot = t + nodePos.h - elPos.h; // beyond bottom: > 0
					var s, old;
					if(r * l > 0 && (!!el.scrollLeft || el == scrollRoot || el.scrollWidth > el.offsetHeight)){
						s = Math[l < 0? "max" : "min"](l, r);
						if(rtl && ((isIE == 8 && !backCompat) || has("trident") >= 5)){ s = -s; }
						old = el.scrollLeft;
						scrollElementBy(el, s, 0);
						s = el.scrollLeft - old;
						nodePos.x -= s;
					}
					if(bot * t > 0 && (!!el.scrollTop || el == scrollRoot || el.scrollHeight > el.offsetHeight)){
						s = Math.ceil(Math[t < 0? "max" : "min"](t, bot));
						old = el.scrollTop;
						scrollElementBy(el, 0, s);
						s = el.scrollTop - old;
						nodePos.y -= s;
					}
					el = (el != scrollRoot) && !fixedPos && el.parentNode;
				}
			}catch(error){
				console.error('scrollIntoView: ' + error);
				node.scrollIntoView(false);
			}
		}
	};

	has("extend-dojo") && lang.setObject("dojo.window", window);

	return window;
});