/*
 
JQuery Hijax plugin:
~~~~~~~~~~~~~~~~~~~~
@product     JQuery Hijax plugin
@version     1.0.0
@copyright   Copyright (c) 2010 Yaron Tadmor
@site        http://www.yarontadmor.co.cc/hijax
@license     GPL license (http://www.gnu.org/licenses/gpl.html)
@requires    jquery.history.js
 
 
Revision History:
~~~~~~~~~~~~~~~~
0.9.5 - Fixed bug on IE (extra comma in default option list).
0.9.6 - Added support for changing title on Ajax
      - Added support for proper JS handling in Hijaxed links via _hijax_ready.
      - Minor bug fixes for end-cases of IE.
0.9.7 - Changed title handling so title is in "title" tag (instead of a div)
      - Use the content of the source element instead of the element itself
0.9.8 - Slight modification to hash saving code. Solves bug of going back and forward
        to the last page
      - Fixed a bug of .live() for [hijax*=] on FireFox
0.9.9 - Changed _hijax_ready to be an array and not a function.
      - Changed regex script, to a more efficient version, due to problems
        with FF4 and Chrom 10
	  - Replace hash delimiter from "/" to ":" to allow paths in URL
1.0.0 - Replaced dontAjaxInitialPage parameter of init() with initialState.
      - Hande sync of multiple hijaxing (clicking a link before ajax operation ended)
        NOTE: start/end callbacks must take into account that start might be called before end has ended.
      - adde "fail" parameter to endCB.
      - Removed formHref. Forms url must distinguish form submit and history load via form params.
      - Added support for real hash tags which cause scrolling
 
TODO: - take care of HTML validity issues.
      - handle google #!
      - Fix real hash support scrolling (scroll only after loaded when history changes)
 
License and Disclaimer:
~~~~~~~~~~~~~~~~~~~~~~
This software is licensed under the GPL open source license. You may distribute it freely, and
use it in your own software. 
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPLICIT OR IMPLIED, INCLUDING BUT 
NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT 
OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 
 
* - internal use only
 
trg : {[startCB: <start load function>, ]
		[endCB: <end load callback>, ]
		url: <url to load>, - 
		src: <source ID in returned html>,
		*[force: <force data reload even if url/src didn't change>,]
 
		*[formData: <if form a serialized version of form's data>]
 
		}
 
 
targets: { <array of trg objects> }
 
options: { 	trgs: { <array of trg objects> },
			defaults: { src: <default source>, (used for targets with no source reference)
						url: <default url>, (used for targets with no URL)
						startCB: <default start load function>,
						endCB: <default end load function>,
					},
			defaultTrg: <default target>, (used for links/forms with no target reference at all)
			selectionClass: <class to add for selected objects> }
 
*/
 
 
 
(function ($) {
	// global hijax params
	var _init = false;
	var _curHash = "*"; // This causes empty hash (initial page) to load default state (since ""!="*")
	var _numPenddingAjaxLoads = 0, _pendingRequest = null, _pendingScroll = null;
 
 
	// Add hijaxing programmatically to a certain link or form. (can be done by using the hijax attr)
	$.fn.hijax = function (targets) {
		if (!targets)
			targets = {};
 
		return this.each (function() {		
	 		var $this = $(this);		
 
	 		// save the targets passed to us
	 		var locTargets = $.extend (true, {}, targets);
	 		this.hijaxTargets = locTargets;
 
			// register the proper event handler.
			if (!$this.hasClass ("hijax")) {
				if ($this.is ("a"))
					$this.click ($.fn.hijax.event);
				else if ($this.is ("form"))
					$this.submit ($.fn.hijax.event)
			}
		});		
	}
 
	// handles click on hijaxed link or submit
	$.fn.hijax.event = function (e) {
		if (!_init)
			return;
 
		e.preventDefault();
 
		// get targets of object, and override current state with object targets
		var curStateTargets = $.fn.hijax.parseHash (_curHash, true);
		var targets = $.fn.hijax.buildTargets.call (this);
		targets = $.extend (true, curStateTargets, targets);
 
		_pendingScroll = "";
 
		// calc resulting hash
		var newHash = $.fn.hijax.buildHash (targets);		
 
		// save new hash in history, and do ajax calls
		// NOTE: Since targets might contain form data which is not saved in hashs, we disable
		//       plugin for the history load and call do ajax explicitly
		_init = false;
		$.history.load (newHash);
		_init = true;
		$.fn.hijax.doAjax (targets, newHash);		
 
 
	}
 
	// handles click on links containing hash only (href="#<element>")
	$.fn.hijax.hashEvent = function (e) {
		if (!_init)
			return;
 
		e.preventDefault();
 
		// build full hash of link with current state
		var $this = $(this);
 
		var newHash = _curHash.split ("::");
		_pendingScroll = $this.attr('href').substring(1);
		newHash[0] = _pendingScroll;
		newHash = newHash.join ("::");
 
 
		// save new hash in history 
		if (newHash == _curHash)
			// browser won't refresh the history so simulate it.
			$.fn.hijax.historyCB (newHash)
		else
			// (this will trigger doAjax())
			$.history.load (newHash);
			//$.fn.hijax.doAjax (targets, hash);		
	}
 
 
	$.fn.hijax.buildTargets = function () {
		$this = $(this);
 
		var targets = this.hijaxTargets;
		if (!targets)
			targets = {};
 
		// get target=source pairs and update (or add) them
		var connections = $this.attr("hijax");
		if (connections != undefined && connections.length == 0)
				connections = undefined;
		if (connections != undefined)
			connections = connections.split ("&");
		for (connection in connections) {
			connection = connections[connection];
			var split = connection.split ("=");
			var trg = split[0];
			var src = split[1];				
			var newTarget = {};
			newTarget[trg] = { src: src}
			$.extend (true, targets, newTarget);
		}
 
		// if no targets, use default target
		var noTargets = true;
		for (t in targets) { noTargets = false; break; }
		if (noTargets && $.fn.hijax.options.defaultTrg)
			targets[$.fn.hijax.options.defaultTrg] = {};
 
		// Call tag specific code to handle targets
		if ($this.is ("a"))
			targets = $.fn.hijax.buildTargets.a.call (this, targets);
		else if ($this.is ("form"))
			targets = $.fn.hijax.buildTargets.form.call (this, targets);
 
		// add defaults:
		for (t in targets) 
			targets[t] = $.extend (true, {}, $.fn.hijax.options.trgs[t], targets[t]);
 
 
		return (targets);
	}
 
 
	$.fn.hijax.buildTargets.a = function (targets) {
		$this = $(this);
 
		// get url and set it to all requested targets
		var url = $this.attr("href");
		for (trg in targets)
			$.extend (true, targets[trg], { url: url });
//			targets[trg].url = url;
 
		return (targets);
	}
 
 
	$.fn.hijax.buildTargets.form = function (targets) {
		$this = $(this);
 
		// url, alternative href and form data and set to targets
		var url = $this.attr("action");			
		var formData = $this.serialize();
		for (trg in targets)
			$.extend (true, targets[trg], { url: url, formData: formData });
 
		return (targets);
	}
 
 
	$.fn.hijax.buildHash = function (targets) {
		var hash = "";
		for (trg in targets) {
			var trgData = targets[trg];
 
			// if no sourc element or url available, we can't process the target
			if (!trgData.src || !trgData.url)
				continue;
 
			hash += "::" + trg;
			hash += ":" + trgData.src;
			hash += ":" + trgData.url;
		}
 
		return (hash);
	}
 
	$.fn.hijax.parseHash = function (hash, withDefaults) {
		// load the default state
		var targets = {};
		if (withDefaults)
			targets = $.extend (true, {}, $.fn.hijax.options.trgs);
 
		// parse pars of hash
		parts = hash.split ("::");
		parts.shift(); // will always be empty, or not interesting
		for (part in parts) {
			part = parts[part];
			subParts = part.split (":", 3);
			var trg = subParts[0];
			var src = subParts[1];
			var url = subParts[2];
 
			var newTarget = {};
			newTarget[trg] = {url: url, src: src};
			$.extend (true, targets, newTarget);
		}
 
		return (targets);
	}
 
 
	$.fn.hijax.doAjax = function (targets, hash) {
		// if there are still pending requests, wait until they end.
		if (_numPenddingAjaxLoads > 0) {
			_pendingRequest = { targets: targets, hash: hash };
			return;
		}
 
 
		// reset pending ajax
		_numPenddingAjaxLoads = 0;
 
		// get current state
		var curTargets = $.fn.hijax.parseHash (_curHash, false);
 
		// loop and update all targets
		for (trg in targets) {
			var trgData = targets[trg];
 
			// if target hasn't changed and was not forced, ignore it
			var curTrgData = curTargets[trg];
			if (curTrgData &&
				trgData.force != true &&
				trgData.src == curTrgData.src &&
				trgData.url == curTrgData.url &&
				!trgData.formData)
				continue;
 
			if (!trgData.src || !trgData.url)
				continue;
 
 
			// add "ajax" var to URL
			var url = trgData.url;
			if (url.search (/?/) == -1)
				url += "?ajax";
			else
				url += "&ajax";
 
			$.fn.hijax.doAjaxHelper (url, trg, trgData);
		}
 
		if (_numPenddingAjaxLoads == 0)
			$.fn.hijax.allAjaxLoaded();
 
		// change state
		_curHash = hash;
		$.fn.hijax.doSelection(targets);
 
		return;
	}
 
	$.fn.hijax.doAjaxHelper = function (url, trg, trgData) {
		_numPenddingAjaxLoads++;
 
		// setup local data copies for internal functions
		var trgDataLoc = $.extend (true, {}, trgData);
		var trgLocal = trg;
		var $trgLocal = $("#"+trgLocal);
 
		trgDataLoc.startCB.call ($trgLocal, function () {
			var ajaxLoader = $.post(url, trgDataLoc.formData)
				.success (function (data, status, res) {
					var regex_script = /<scriptb[^<]*(?:(?!</script>)<[^<]*)*</script>/gi;
					var regex_head = /<headb[^<]*(?:(?!</head>)<[^<]*)*</head>/gi;
					var regex_title = /<titleb[^<]*(?:(?!</title>)<[^<]*)*</title>/gi;
 
					// extract title data, and remove head
					var titleData = data.match (regex_title);
					data = data.replace (regex_head, "");
 
					// append result to DOM.
					if (trgDataLoc.src && trgDataLoc.src.length) {
						var $tmpDiv = $("<div />").append(data);
						$trgLocal.html ($tmpDiv.find("#"+trgDataLoc.src).contents());
					}
					else
						$trgLocal.html (data);
 
 
					// copy title data
					var trgTitleAttr = "hijax"+trgLocal;
					if (titleData) {
						titleData = titleData[0];
						$titleData = $(titleData);
						var titleText = $titleData.attr("hijaxTitle");
						if (titleText)
							$("title").attr ("hijaxTitle", titleText);
						var trgTitleText = $titleData.attr (trgTitleAttr);
						if (trgTitleText)
							$("title").attr (trgTitleAttr, trgTitleText);
					}
 
					// trigger the loaded event for the target
					var $trg = $("#"+trgLocal);
					$trg.trigger ('hijaxReadyEvent');
 
					// setup title
					$.fn.hijax.doTitle();
 
					// end callback
					trgDataLoc.endCB.call($trgLocal, true);
				})
				.error (function() {
					// end callback
					trgDataLoc.endCB.call($trgLocal, false);
				})
				.complete (function() {
					_numPenddingAjaxLoads--;
					if (_numPenddingAjaxLoads == 0)
						$.fn.hijax.allAjaxLoaded();
				});
		});	
	}
 
	$.fn.hijax.allAjaxLoaded = function ()
	{
		// if there's a pending request, load it.
		if (_pendingRequest) {
			var tmp = _pendingRequest;
			_pendingRequest = null;
			$.fn.hijax.doAjax (tmp.targets, tmp.hash);
		}
 
		// handle scrolling
		if (_pendingScroll) {
			if (typeof (_pendingScroll) === typeof ("")) {
				if (_pendingScroll.length > 0) {
					var $targetElem = $("#"+_pendingScroll);
					if ($targetElem[0]) {
						var offset = $targetElem.offset();
						$('html, body').scrollTop (offset.top);
					}
				}
			}
			else {
				$('html,body').scrollTop(_pendingScroll)
			}
 
			_pendingScroll = null;
		}	
 
	}
 
 
	// handles adding selection attribute by loaded page
	$.fn.hijax.doSelection = function (curTargets) {
		$("[hijax*=], [hijaxTargets*=]").each (function() {
			var objTargets = $.fn.hijax.buildTargets.call (this);
			var match = true; 
			var hasTargets = false;
			for (trg in objTargets) {
				hasTargets = true;
				if (objTargets[trg].src != curTargets[trg].src ||
					objTargets[trg].url != curTargets[trg].url ||
					objTargets[trg].formData) {
					match = false;
					break;
				}
			}
 
			// get object to change
			$obj = $(this);
			var selectionTarget = $obj.attr("hijaxSelectionTarget");
			if (selectionTarget)
				var $obj = $obj.closest(selectionTarget);
 
			// change selection
			if (match && hasTargets)
				$obj.addClass ($.fn.hijax.options.selectionClass);
			else
				$obj.removeClass ($.fn.hijax.options.selectionClass);
		});
 
	}
 
 
	// handles setting the title
	$.fn.hijax.doTitle = function () {	
		var $title = $("title");
 
		// If we have hijax title on, parse all targets for the text.
		var titleText = $title.attr ("hijaxTitle");
		if (titleText) {
			for (trg in $.fn.hijax.options.trgs) {
				// get text for target
				var trgTitleAtr = "hijax"+trg;
				var trgTitleTxt = $title.attr (trgTitleAtr);
				if (!trgTitleTxt)
					continue;
 
				// put target's text in title
				titleText = titleText.replace ("#"+trg, trgTitleTxt);
			}
 
			// if we have text for ALL titles, we can use it.
			if (titleText.search ("#") == -1)
				document.title = titleText;
		}
 
	}
 
 
 
	$.fn.hijax.historyCB = function (hash) {
		if (!_init)
			return;
 
		// save current scroll position
		var curScroll = $('body').scrollTop()
 
		// get targets by hash
		var targets = $.fn.hijax.parseHash (hash, true);
		// load the state
		$.fn.hijax.doAjax (targets, hash);	
 
		// remember scroll position, so we can reset it back after loading
 
		// restore current scroll position until all ajax is done
		if (_numPenddingAjaxLoads > 0) {
			_pendingScroll = $('body').scrollTop();
			$('html,body').scrollTop(curScroll)
		}
 
 
	}
 
 
	$.hijax = function (options, initialState) {
		if (_init)
			return;
 
		// update options
		$.extend (true, $.fn.hijax.options, options || {});
 
		// if we have a default target, make sure it's in the trgs.
		if ($.fn.hijax.options.defaultTrg) {
			var newTarget = {};
			newTarget[$.fn.hijax.options.defaultTrg] = { }
			$.extend (true, $.fn.hijax.options.trgs, newTarget);
		}
 
		// init targets with default values if needed
		for (trg in $.fn.hijax.options.trgs) {
			$.fn.hijax.options.trgs[trg] = $.extend (true, {}, $.fn.hijax.options.defaults, $.fn.hijax.options.trgs[trg])
		}
 
		// init the history module
		if (initialState === true)
			initialState = $.extend (true, {}, $.fn.hijax.options.trgs);
		if (initialState) {
			_curHash = $.fn.hijax.buildHash (initialState);
			$.fn.hijax.doSelection (initialState);
		}
 
 
		_init = true;
 
		$.history.init($.fn.hijax.historyCB, { unescape: true });
	}
 
	// BW compat
	$.fn.hijax.init = function (options, initialState) {
		alert ("HIJAX ERROR:nCode is written for an older version of the Hijax plugin.n"+
				"You must change your site code accordingly:n"+
				"- Init function changed from $.fn.hijax.init to $.hijaxn" +
				"- formHref and href attribute on form is no longer supported,n" +
				"  You should make sure your form url knows when form was submittedn" +
				"  and when it was loaded via history according to form parameters.n" +
				"nnPlease see docs for more information.nn");
 	}
 
	$.fn.hijax.defaultStartCB = function (cb) {
		cb();
	}
 
	$.fn.hijax.defaultEndCB = function () {
	}
 
 
	// basic options so we have call backs.
	$.fn.hijax.options = {trgs: {},
							defaults: { src: null,
										url: null,
										startCB: $.fn.hijax.defaultStartCB,
										endCB: $.fn.hijax.defaultEndCB },
							defaultTrg: undefined,
							selectionClass: "selected" };
 
 
 
	// Install handler to catch all hijax HTML elements (the *= is to allow empty attribute)
	if ($.browser.msie) {
		$("a[hijax*=]").live ("click", $.fn.hijax.event);
		$("form[hijax*=]").live ("submit", $.fn.hijax.event);
	}
	else {
		$("a[hijax]").live ("click", $.fn.hijax.event);
		$("form[hijax]").live ("submit", $.fn.hijax.event);
	}
 
	// install handlers to catch hash only links
	$("a[href^=#]").live ("click", $.fn.hijax.hashEvent);
 
 
}) (jQuery);