/* Reference Article:
Dustin Diaz:
http://www.dustindiaz.com/top-ten-javascript/
*/

/* addEvent: simplified event attachment */
function addEvent( obj, type, fn ) {
	if (obj.addEventListener) {
		obj.addEventListener( type, fn, false );
		EventCache.add(obj, type, fn);
	}
	else if (obj.attachEvent) {
		obj["e"+type+fn] = fn;
		obj[type+fn] = function() { obj["e"+type+fn]( window.event ); }
		obj.attachEvent( "on"+type, obj[type+fn] );
		EventCache.add(obj, type, fn);
	}
	else {
		obj["on"+type] = obj["e"+type+fn];
	}
}
	
var EventCache = function(){
	var listEvents = [];
	return {
		listEvents : listEvents,
		add : function(node, sEventName, fHandler){
			listEvents.push(arguments);
		},
		flush : function(){
			var i, item;
			for(i = listEvents.length - 1; i >= 0; i = i - 1){
				item = listEvents[i];
				if(item[0].removeEventListener){
					item[0].removeEventListener(item[1], item[2], item[3]);
				};
				if(item[1].substring(0, 2) != "on"){
					item[1] = "on" + item[1];
				};
				if(item[0].detachEvent){
					item[0].detachEvent(item[1], item[2]);
				};
				item[0][item[1]] = null;
			};
		}
	};
}();
addEvent(window,'unload',EventCache.flush);

/* window 'load' attachment */
function addLoadEvent(func) {
	var oldonload = window.onload;
	if (typeof window.onload != 'function') {
		window.onload = func;
	}
	else {
		window.onload = function() {
			oldonload();
			func();
		}
	}
}

/* grab Elements from the DOM by className */
function getElementsByClass(searchClass,node,tag) {
	var classElements = new Array();
	if ( node == null )
		node = document;
	if ( tag == null )
		tag = '*';
	var els = node.getElementsByTagName(tag);
	var elsLen = els.length;
	var pattern = new RegExp("(^|\\s)"+searchClass+"(\\s|$)");
	for (i = 0, j = 0; i < elsLen; i++) {
		if ( pattern.test(els[i].className) ) {
			classElements[j] = els[i];
			j++;
		}
	}
	return classElements;
}

/* toggle an element's display */
function toggle(obj) {
	var el = document.getElementById(obj);
	if ( el.style.display != 'none' ) {
		el.style.display = 'none';
	}
	else {
		el.style.display = '';
	}
}

/* insert an element after a particular node */
function insertAfter(parent, node, referenceNode) {
	parent.insertBefore(node, referenceNode.nextSibling);
}

/* Array prototype, matches value in array: returns bool */
Array.prototype.inArray = function (value) {
	var i;
	for (i=0; i < this.length; i++) {
		if (this[i] === value) {
			return true;
		}
	}
	return false;
};

/* get, set, and delete cookies */
function getCookie( name ) {
	var start = document.cookie.indexOf( name + "=" );
	var len = start + name.length + 1;
	if ( ( !start ) && ( name != document.cookie.substring( 0, name.length ) ) ) {
		return null;
	}
	if ( start == -1 ) return null;
	var end = document.cookie.indexOf( ";", len );
	if ( end == -1 ) end = document.cookie.length;
	return unescape( document.cookie.substring( len, end ) );
}
	
function setCookie( name, value, expires, path, domain, secure ) {
	var today = new Date();
	today.setTime( today.getTime() );
	if ( expires ) {
		expires = expires * 1000 * 60 * 60 * 24;
	}
	var expires_date = new Date( today.getTime() + (expires) );
	document.cookie = name+"="+escape( value ) +
		( ( expires ) ? ";expires="+expires_date.toGMTString() : "" ) + //expires.toGMTString()
		( ( path ) ? ";path=" + path : "" ) +
		( ( domain ) ? ";domain=" + domain : "" ) +
		( ( secure ) ? ";secure" : "" );
}
	
function deleteCookie( name, path, domain ) {
	if ( getCookie( name ) ) document.cookie = name + "=" +
			( ( path ) ? ";path=" + path : "") +
			( ( domain ) ? ";domain=" + domain : "" ) +
			";expires=Thu, 01-Jan-1970 00:00:01 GMT";
}

/* quick getElement reference */
function $() {
	var elements = new Array();
	for (var i = 0; i < arguments.length; i++) {
		var element = arguments[i];
		if (typeof element == 'string')
			element = document.getElementById(element);
		if (arguments.length == 1)
			return element;
		elements.push(element);
	}
	return elements;
}

/* document.getElementsBySelector(selector)
   - returns an array of element objects from the current document
     matching the CSS selector. Selectors can contain element names, 
     class names and ids and can be nested. For example:
     
       elements = document.getElementsBySelect('div#main p a.external')
     
     Will return an array of all 'a' elements with 'external' in their 
     class attribute that are contained inside 'p' elements that are 
     contained inside the 'div' element which has id="main"

   New in version 0.4: Support for CSS2 and CSS3 attribute selectors:
   See http://www.w3.org/TR/css3-selectors/#attribute-selectors

   Version 0.4 - Simon Willison, March 25th 2003
   -- Works in Phoenix 0.5, Mozilla 1.3, Opera 7, Internet Explorer 6, Internet Explorer 5 on Windows
   -- Opera 7 fails 
*/

function getAllChildren(e) {
  // Returns all children of element. Workaround required for IE5/Windows. Ugh.
  return e.all ? e.all : e.getElementsByTagName('*');
}

document.getElementsBySelector = function(selector) {
  // Attempt to fail gracefully in lesser browsers
  if (!document.getElementsByTagName) {
    return new Array();
  }
  // Split selector in to tokens
  var tokens = selector.split(' ');
  var currentContext = new Array(document);
  for (var i = 0; i < tokens.length; i++) {
    token = tokens[i].replace(/^\s+/,'').replace(/\s+$/,'');;
    if (token.indexOf('#') > -1) {
      // Token is an ID selector
      var bits = token.split('#');
      var tagName = bits[0];
      var id = bits[1];
      var element = document.getElementById(id);
      if (tagName && element.nodeName.toLowerCase() != tagName) {
        // tag with that ID not found, return false
        return new Array();
      }
      // Set currentContext to contain just this element
      currentContext = new Array(element);
      continue; // Skip to next token
    }
    if (token.indexOf('.') > -1) {
      // Token contains a class selector
      var bits = token.split('.');
      var tagName = bits[0];
      var className = bits[1];
      if (!tagName) {
        tagName = '*';
      }
      // Get elements matching tag, filter them for class selector
      var found = new Array;
      var foundCount = 0;
      for (var h = 0; h < currentContext.length; h++) {
        var elements;
        if (tagName == '*') {
            elements = getAllChildren(currentContext[h]);
        } else {
            elements = currentContext[h].getElementsByTagName(tagName);
        }
        for (var j = 0; j < elements.length; j++) {
          found[foundCount++] = elements[j];
        }
      }
      currentContext = new Array;
      var currentContextIndex = 0;
      for (var k = 0; k < found.length; k++) {
        if (found[k].className && found[k].className.match(new RegExp('\\b'+className+'\\b'))) {
          currentContext[currentContextIndex++] = found[k];
        }
      }
      continue; // Skip to next token
    }
    // Code to deal with attribute selectors
    if (token.match(/^(\w*)\[(\w+)([=~\|\^\$\*]?)=?"?([^\]"]*)"?\]$/)) {
      var tagName = RegExp.$1;
      var attrName = RegExp.$2;
      var attrOperator = RegExp.$3;
      var attrValue = RegExp.$4;
      if (!tagName) {
        tagName = '*';
      }
      // Grab all of the tagName elements within current context
      var found = new Array;
      var foundCount = 0;
      for (var h = 0; h < currentContext.length; h++) {
        var elements;
        if (tagName == '*') {
            elements = getAllChildren(currentContext[h]);
        } else {
            elements = currentContext[h].getElementsByTagName(tagName);
        }
        for (var j = 0; j < elements.length; j++) {
          found[foundCount++] = elements[j];
        }
      }
      currentContext = new Array;
      var currentContextIndex = 0;
      var checkFunction; // This function will be used to filter the elements
      switch (attrOperator) {
        case '=': // Equality
          checkFunction = function(e) { return (e.getAttribute(attrName) == attrValue); };
          break;
        case '~': // Match one of space seperated words 
          checkFunction = function(e) { return (e.getAttribute(attrName).match(new RegExp('\\b'+attrValue+'\\b'))); };
          break;
        case '|': // Match start with value followed by optional hyphen
          checkFunction = function(e) { return (e.getAttribute(attrName).match(new RegExp('^'+attrValue+'-?'))); };
          break;
        case '^': // Match starts with value
          checkFunction = function(e) { return (e.getAttribute(attrName).indexOf(attrValue) == 0); };
          break;
        case '$': // Match ends with value - fails with "Warning" in Opera 7
          checkFunction = function(e) { return (e.getAttribute(attrName).lastIndexOf(attrValue) == e.getAttribute(attrName).length - attrValue.length); };
          break;
        case '*': // Match ends with value
          checkFunction = function(e) { return (e.getAttribute(attrName).indexOf(attrValue) > -1); };
          break;
        default :
          // Just test for existence of attribute
          checkFunction = function(e) { return e.getAttribute(attrName); };
      }
      currentContext = new Array;
      var currentContextIndex = 0;
      for (var k = 0; k < found.length; k++) {
        if (checkFunction(found[k])) {
          currentContext[currentContextIndex++] = found[k];
        }
      }
      // alert('Attribute Selector: '+tagName+' '+attrName+' '+attrOperator+' '+attrValue);
      continue; // Skip to next token
    }
    // If we get here, token is JUST an element (not a class or ID selector)
    tagName = token;
    var found = new Array;
    var foundCount = 0;
    for (var h = 0; h < currentContext.length; h++) {
      var elements = currentContext[h].getElementsByTagName(tagName);
      for (var j = 0; j < elements.length; j++) {
        found[foundCount++] = elements[j];
      }
    }
    currentContext = found;
  }
  return currentContext;
}

	function changeOpac(opacity, id) { 
		var object = document.getElementById(id).style; 
		object.opacity = (opacity / 100); 
		object.MozOpacity = (opacity / 100); 
		object.KhtmlOpacity = (opacity / 100); 
		object.filter = "alpha(opacity=" + opacity + ")"; 
	} 
	
	function opacity(id, opacStart, opacEnd, millisec) { 
		//speed for each frame 
		var speed = Math.round(millisec / 100); 
		var timer = 0; 
	
		//determine the direction for the blending, if start and end are the same nothing happens 
		if(opacStart > opacEnd) { 
			for(i = opacStart; i >= opacEnd; i--) { 
				setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed)); 
				timer++; 
			} 
		} else if(opacStart < opacEnd) { 
			for(i = opacStart; i <= opacEnd; i++) 
				{ 
				setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed)); 
				timer++; 
			} 
		} 
	} 
	
	function shiftOpacity(id, millisec) { 
		//if an element is invisible, make it visible, else make it ivisible 
		if(document.getElementById(id).style.opacity == 0) { 
			opacity(id, 0, 100, millisec); 
		} else { 
			opacity(id, 100, 0, millisec); 
		} 
	} 

	function changeImage(urlThumb,imageUrl)
	{
		document.getElementById("masterImage").style.opacity = 0;
		document.getElementById("masterImage").src = urlThumb;
		document.getElementById("masterLink").href = imageUrl;
		shiftOpacity('masterImage', 500);
	}

/* That revolting regular expression explained 
/^(\w+)\[(\w+)([=~\|\^\$\*]?)=?"?([^\]"]*)"?\]$/
  \---/  \---/\-------------/    \-------/
    |      |         |               |
    |      |         |           The value
    |      |    ~,|,^,$,* or =
    |   Attribute 
   Tag
*/