window.js

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

	// 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, if it is not already.

			// don't rely on node.scrollIntoView working just because the function is there

			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"), isWK = has("webkit");
				// if an untested browser, then use the native method
				if((!(has("mozilla") || isIE || isWK || has("opera")) || node == body || node == html) && (typeof node.scrollIntoView != "undefined")){
					node.scrollIntoView(false); // short-circuit to native if possible
					return;
				}
				var backCompat = doc.compatMode == 'BackCompat',
					clientAreaRoot = (isIE >= 9 && "frameElement" in node.ownerDocument.parentWindow)
						? ((html.clientHeight > 0 && html.clientWidth > 0 && (body.clientHeight == 0 || body.clientWidth == 0 || body.clientHeight > html.clientHeight || body.clientWidth > html.clientWidth)) ? html : body)
						: (backCompat ? body : html),
					scrollRoot = isWK ? body : clientAreaRoot,
					rootWidth = clientAreaRoot.clientWidth,
					rootHeight = clientAreaRoot.clientHeight,
					rtl = !geom.isBodyLtr(doc),
					nodePos = pos || geom.position(node),
					el = node.parentNode,
					isFixed = function(el){
						return ((isIE <= 6 || (isIE && backCompat))? false : (style.get(el, 'position').toLowerCase() == "fixed"));
					};
				if(isFixed(node)){ return; } // nothing to do

				while(el){
					if(el == body){ el = scrollRoot; }
					var elPos = geom.position(el),
						fixedPos = isFixed(el);

					if(el == scrollRoot){
						elPos.w = rootWidth; elPos.h = rootHeight;
						if(scrollRoot == html && isIE && rtl){ elPos.x += scrollRoot.offsetWidth-elPos.w; } // IE workaround where scrollbar causes negative x
						if(elPos.x < 0 || !isIE){ elPos.x = 0; } // IE can have values > 0
						if(elPos.y < 0 || !isIE){ 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){
							elPos.w = clientSize;
							elPos.x += (rtl && (isIE || el.clientLeft > pb.l/*Chrome*/)) ? scrollBarSize : 0;
						}
						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
						r = l + nodePos.w - elPos.w, // beyond right: > 0
						bot = t + nodePos.h - elPos.h; // beyond bottom: > 0
					if(r * l > 0){
						var s = Math[l < 0? "max" : "min"](l, r);
						if(rtl && ((isIE == 8 && !backCompat) || isIE >= 9)){ s = -s; }
						nodePos.x += el.scrollLeft;
						el.scrollLeft += s;
						nodePos.x -= el.scrollLeft;
					}
					if(bot * t > 0){
						nodePos.y += el.scrollTop;
						el.scrollTop += Math[t < 0? "max" : "min"](t, bot);
						nodePos.y -= el.scrollTop;
					}
					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;
});