/**
 * jQuery hashchange 1.0.0
 * 
 * (based on jquery.history)
 *
 * Copyright (c) 2008 Chris Leishman (chrisleishman.com)
 * Dual licensed under the MIT (MIT-LICENSE.txt)
 * and GPL (GPL-LICENSE.txt) licenses.
 */
(function($) {

$.fn.extend({
    hashchange: function(callback) { this.bind('hashchange', callback) },
    openOnClick: function(href) {
		if (href === undefined || href.length == 0)
			href = '#';
		return this.click(function(ev) {
			if (href && href.charAt(0) == '#') {
				// execute load in separate call stack
				window.setTimeout(function() { $.locationHash(href) }, 0);
			} else {
				window.location(href);
			}
			ev.stopPropagation();
			return false;
		});
    }
});

// IE 8 introduces the hashchange event natively - so nothing more to do
if ($.browser.msie && document.documentMode && document.documentMode >= 8) {
	$.extend({
		locationHash: function(hash) {
	        if (!hash) hash = '#';
	        else if (hash.charAt(0) != '#') hash = '#' + hash;
	        location.hash = hash;
	    }
	});
	return;
}

var curHash;
// hidden iframe for IE (earlier than 8)
var iframe;

$.extend({
	locationHash: function(hash) {
		if (curHash === undefined) return;

		if (!hash) hash = '#';
		else if (hash.charAt(0) != '#') hash = '#' + hash;
		
		location.hash = hash;
		
		if (curHash == hash) return;
		curHash = hash;
		
		if ($.browser.msie) updateIEFrame(hash);
		$.event.trigger('hashchange');
	}
});

$(document).ready(function() {
    curHash = location.hash;
    if ($.browser.msie) {
        // stop the callback firing twice during init if no hash present
        if (curHash == '') curHash = '#';
        // add hidden iframe for IE
        iframe = $('<iframe />').hide().get(0);
        $('body').prepend(iframe);
        updateIEFrame(location.hash);
        setInterval(checkHashIE, 100);
    } else {
        setInterval(checkHash, 100);
    }
});
$(window).unload(function() { iframe = null });

function checkHash() {
    var hash = location.hash;
    if (hash != curHash) {
        curHash = hash;
        $.event.trigger('hashchange');
    }
}

if ($.browser.msie) {
    // Attach a live handler for any anchor links
    $('a[href^=#]').live('click', function() {
        var hash = $(this).attr('href');
        // Don't intercept the click if there is an existing anchor on the page
        // that matches this hash
        if ($(hash).length == 0 && $('a[name='+hash.slice(1)+']').length == 0) {
            $.locationHash(hash);
            return false;
        }
    });
}

function checkHashIE() {
    // On IE, check for location.hash of iframe
    var idoc = iframe.contentDocument || iframe.contentWindow.document;
    var hash = idoc.location.hash;
    if (hash == '') hash = '#';

    if (hash != curHash) {
        if (location.hash != hash) location.hash = hash;
        curHash = hash;
        $.event.trigger('hashchange');
    }
}

function updateIEFrame(hash) {
    if (hash == '#') hash = '';
    var idoc = iframe.contentWindow.document;
    idoc.open();
    idoc.close();
    if (idoc.location.hash != hash) idoc.location.hash = hash;
}

})(jQuery);

