build custom layer of Dojo to speed up loading of tt-rss (refs #293)

1 files changed, 228 insertions, 126 deletions

diff --git a/lib/dojo/hash.js b/lib/dojo/hash.js
index b73d37058..6ef74b521 100644
--- a/lib/dojo/hash.js
+++ b/lib/dojo/hash.js
@@ -5,133 +5,235 @@
 */
 
 
-if(!dojo._hasResource["dojo.hash"]){
-dojo._hasResource["dojo.hash"]=true;
+if(!dojo._hasResource["dojo.hash"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
+dojo._hasResource["dojo.hash"] = true;
 dojo.provide("dojo.hash");
+//TODOC: where does this go?
+// summary:
+//		Methods for monitoring and updating the hash in the browser URL.
+//
+// example:
+//		dojo.subscribe("/dojo/hashchange", context, callback);
+//
+//		function callback (hashValue){
+//			// do something based on the hash value.
+// 		}
+
 (function(){
-dojo.hash=function(_1,_2){
-if(!arguments.length){
-return _3();
-}
-if(_1.charAt(0)=="#"){
-_1=_1.substring(1);
-}
-if(_2){
-_4(_1);
-}else{
-location.href="#"+_1;
-}
-return _1;
-};
-var _5=null,_6=null,_7=dojo.config.hashPollFrequency||100;
-function _8(_9,_a){
-var i=_9.indexOf(_a);
-return (i>=0)?_9.substring(i+1):"";
-};
-function _3(){
-return _8(location.href,"#");
-};
-function _b(){
-dojo.publish("/dojo/hashchange",[_3()]);
-};
-function _c(){
-if(_3()===_5){
-return;
-}
-_5=_3();
-_b();
-};
-function _4(_d){
-if(_6){
-if(_6.isTransitioning()){
-setTimeout(dojo.hitch(null,_4,_d),_7);
-return;
-}
-var _e=_6.iframe.location.href;
-var _f=_e.indexOf("?");
-_6.iframe.location.replace(_e.substring(0,_f)+"?"+_d);
-return;
-}
-location.replace("#"+_d);
-_c();
-};
-function _10(){
-var ifr=document.createElement("iframe"),_11="dojo-hash-iframe",_12=dojo.config.dojoBlankHtmlUrl||dojo.moduleUrl("dojo","resources/blank.html");
-ifr.id=_11;
-ifr.src=_12+"?"+_3();
-ifr.style.display="none";
-document.body.appendChild(ifr);
-this.iframe=dojo.global[_11];
-var _13,_14,_15,_16,_17,_18=this.iframe.location;
-function _19(){
-_5=_3();
-_13=_17?_5:_8(_18.href,"?");
-_14=false;
-_15=null;
-};
-this.isTransitioning=function(){
-return _14;
-};
-this.pollLocation=function(){
-if(!_17){
-try{
-var _1a=_8(_18.href,"?");
-if(document.title!=_16){
-_16=this.iframe.document.title=document.title;
-}
-}
-catch(e){
-_17=true;
-console.error("dojo.hash: Error adding history entry. Server unreachable.");
-}
-}
-var _1b=_3();
-if(_14&&_5===_1b){
-if(_17||_1a===_15){
-_19();
-_b();
-}else{
-setTimeout(dojo.hitch(this,this.pollLocation),0);
-return;
-}
-}else{
-if(_5===_1b&&(_17||_13===_1a)){
-}else{
-if(_5!==_1b){
-_5=_1b;
-_14=true;
-_15=_1b;
-ifr.src=_12+"?"+_15;
-_17=false;
-setTimeout(dojo.hitch(this,this.pollLocation),0);
-return;
-}else{
-if(!_17){
-location.href="#"+_18.search.substring(1);
-_19();
-_b();
-}
-}
-}
-}
-setTimeout(dojo.hitch(this,this.pollLocation),_7);
-};
-_19();
-setTimeout(dojo.hitch(this,this.pollLocation),_7);
-};
-dojo.addOnLoad(function(){
-if("onhashchange" in dojo.global&&(!dojo.isIE||(dojo.isIE>=8&&document.compatMode!="BackCompat"))){
-dojo.connect(dojo.global,"onhashchange",_b);
-}else{
-if(document.addEventListener){
-_5=_3();
-setInterval(_c,_7);
-}else{
-if(document.attachEvent){
-_6=new _10();
-}
-}
-}
-});
+	dojo.hash = function(/* String? */ hash, /* Boolean? */ replace){
+		//	summary:
+		//		Gets or sets the hash string.
+		//	description:
+		//		Handles getting and setting of location.hash.
+		//		 - If no arguments are passed, acts as a getter.
+		//		 - If a string is passed, acts as a setter.
+		//	hash: 
+		//		String: the hash is set - #string.
+		//	replace:
+		//		Boolean: If true, updates the hash value in the current history 
+		//			state instead of creating a new history state.
+		//	returns:
+		//		when used as a getter, returns the current hash string.
+		//		when used as a setter, returns the new hash string.
+		
+		// getter
+		if(!arguments.length){
+			return _getHash();
+		}
+		// setter
+		if(hash.charAt(0) == "#"){
+			hash = hash.substring(1);
+		}
+		if(replace){
+			_replace(hash);
+		}else{
+			location.href = "#" + hash;
+		}
+		return hash; // String
+	}
+
+	// Global vars
+	var _recentHash = null,
+		_ieUriMonitor = null,
+		_pollFrequency = dojo.config.hashPollFrequency || 100;
+
+	//Internal functions
+	function _getSegment(str, delimiter){
+		var i = str.indexOf(delimiter);
+		return (i >= 0) ? str.substring(i+1) : "";  
+	}
+	
+	function _getHash(){
+		return _getSegment(location.href, "#");
+	}
+
+	function _dispatchEvent(){
+		dojo.publish("/dojo/hashchange", [_getHash()]);
+	}
+
+	function _pollLocation(){
+		if(_getHash() === _recentHash){
+			return;
+		}
+		_recentHash = _getHash();
+		_dispatchEvent();
+	}
+	
+	function _replace(hash){
+		if(_ieUriMonitor){
+			if(_ieUriMonitor.isTransitioning()){
+				setTimeout(dojo.hitch(null,_replace,hash), _pollFrequency);
+				return;
+			}
+			var href = _ieUriMonitor.iframe.location.href;
+			var index = href.indexOf('?');
+			// main frame will detect and update itself
+			_ieUriMonitor.iframe.location.replace(href.substring(0, index) + "?" + hash);
+			return;
+		}
+		location.replace("#"+hash);
+		_pollLocation();
+	}
+
+	function IEUriMonitor(){
+		// summary:
+		//		Determine if the browser's URI has changed or if the user has pressed the 
+		//		back or forward button. If so, call _dispatchEvent.
+		//
+		//	description:
+		//		IE doesn't add changes to the URI's hash into the history unless the hash
+		//		value corresponds to an actual named anchor in the document. To get around
+		//      this IE difference, we use a background IFrame to maintain a back-forward
+		//		history, by updating the IFrame's query string to correspond to the
+		//		value of the main browser location's hash value.
+		//
+		//		E.g. if the value of the browser window's location changes to
+		//
+		//		#action=someAction
+		//
+		//		... then we'd update the IFrame's source to:
+		//
+		//		?action=someAction
+		//
+		//		This design leads to a somewhat complex state machine, which is
+		//		described below:
+		//
+		//		s1: Stable state - neither the window's location has changed nor
+		//			has the IFrame's location. Note that this is the 99.9% case, so
+		//			we optimize for it.
+		//			Transitions: s1, s2, s3
+		//		s2: Window's location changed - when a user clicks a hyperlink or
+		//			code programmatically changes the window's URI.
+		//			Transitions: s4
+		//		s3: Iframe's location changed as a result of user pressing back or
+		//			forward - when the user presses back or forward, the location of
+		//			the background's iframe changes to the previous or next value in
+		//			its history.
+		//			Transitions: s1
+		//		s4: IEUriMonitor has programmatically changed the location of the
+		//			background iframe, but it's location hasn't yet changed. In this
+		//			case we do nothing because we need to wait for the iframe's
+		//			location to reflect its actual state.
+		//			Transitions: s4, s5
+		//		s5:	IEUriMonitor has programmatically changed the location of the
+		//			background iframe, and the iframe's location has caught up with
+		//			reality. In this case we need to transition to s1.
+		//			Transitions: s1
+		//
+		//		The hashchange event is always dispatched on the transition back to s1.
+		//
+
+		// create and append iframe
+		var ifr = document.createElement("iframe"),
+			IFRAME_ID = "dojo-hash-iframe",
+			ifrSrc = dojo.config.dojoBlankHtmlUrl || dojo.moduleUrl("dojo", "resources/blank.html");
+		ifr.id = IFRAME_ID;
+		ifr.src = ifrSrc + "?" + _getHash();
+		ifr.style.display = "none";
+		document.body.appendChild(ifr);
+
+		this.iframe = dojo.global[IFRAME_ID];
+		var recentIframeQuery, transitioning, expectedIFrameQuery, docTitle, ifrOffline,
+			iframeLoc = this.iframe.location;
+
+		function resetState(){
+			_recentHash = _getHash();
+			recentIframeQuery = ifrOffline ? _recentHash : _getSegment(iframeLoc.href, "?");
+			transitioning = false;
+			expectedIFrameQuery = null;
+		}
+
+		this.isTransitioning = function(){
+			return transitioning;
+		}
+		
+		this.pollLocation = function(){
+			if(!ifrOffline) {
+				try{
+					//see if we can access the iframe's location without a permission denied error
+					var iframeSearch = _getSegment(iframeLoc.href, "?");
+					//good, the iframe is same origin (no thrown exception)
+					if(document.title != docTitle){ //sync title of main window with title of iframe.
+						docTitle = this.iframe.document.title = document.title;
+					}
+				}catch(e){
+					//permission denied - server cannot be reached.
+					ifrOffline = true;
+					console.error("dojo.hash: Error adding history entry. Server unreachable.");
+				}
+			}
+			var hash = _getHash();
+			if(transitioning && _recentHash === hash){
+				// we're in an iframe transition (s4 or s5)
+				if(ifrOffline || iframeSearch === expectedIFrameQuery){
+					// s5 (iframe caught up to main window or iframe offline), transition back to s1
+					resetState();
+					_dispatchEvent();
+				}else{
+					// s4 (waiting for iframe to catch up to main window)
+					setTimeout(dojo.hitch(this,this.pollLocation),0);
+					return;
+				}
+			}else if(_recentHash === hash && (ifrOffline || recentIframeQuery === iframeSearch)){
+				// we're in stable state (s1, iframe query == main window hash), do nothing
+			}else{
+				// the user has initiated a URL change somehow.
+				// sync iframe query <-> main window hash
+				if(_recentHash !== hash){
+					// s2 (main window location changed), set iframe url and transition to s4
+					_recentHash = hash;
+					transitioning = true;
+					expectedIFrameQuery = hash;
+					ifr.src = ifrSrc + "?" + expectedIFrameQuery;
+					ifrOffline = false;	//we're updating the iframe src - set offline to false so we can check again on next poll.
+					setTimeout(dojo.hitch(this,this.pollLocation),0); //yielded transition to s4 while iframe reloads.
+					return;
+				}else if(!ifrOffline){
+					// s3 (iframe location changed via back/forward button), set main window url and transition to s1.
+					location.href = "#" + iframeLoc.search.substring(1);
+					resetState();
+					_dispatchEvent();
+				}
+			}
+			setTimeout(dojo.hitch(this,this.pollLocation), _pollFrequency);
+		}
+		resetState(); // initialize state (transition to s1)
+		setTimeout(dojo.hitch(this,this.pollLocation), _pollFrequency);
+	}
+	dojo.addOnLoad(function(){
+		if("onhashchange" in dojo.global && (!dojo.isIE || (dojo.isIE >= 8 && document.compatMode != "BackCompat"))){	//need this IE browser test because "onhashchange" exists in IE8 in IE7 mode
+			dojo.connect(dojo.global,"onhashchange",_dispatchEvent);
+		}else{
+			if(document.addEventListener){ // Non-IE
+				_recentHash = _getHash();
+				setInterval(_pollLocation, _pollFrequency); //Poll the window location for changes
+			}else if(document.attachEvent){ // IE7-
+				//Use hidden iframe in versions of IE that don't have onhashchange event
+				_ieUriMonitor = new IEUriMonitor();
+			} 
+			// else non-supported browser, do nothing.
+		}
+	});
 })();
+
 }