ThinkCo.namespace ( 'util.Dom' );

/**
 * [TODO] make nice like yahoo
 */
ThinkCo.util.Dom.getAncestorsByClass = function ( obj, className, tag )
{
	className		= className			|| false;
	tag			= tag				|| false;

	// an array to store the ancestors/parent nodes that match the className
	var ancestors	= new Array;
	// start with the parent of the object
	var parent		= obj.parentNode;
	// set a maximum number or parent nodes to look through - may be removed
	var iteration	= 20;
	// loop backwards through the DOM
	while ( parent && iteration-- )
	{
		// if the element has a matching class, add it to the array
		if ( YAHOO.util.Dom.hasClass ( parent, className ) || !className )
		{
			if ( !tag || ( tag && parent.nodeName.toLowerCase ( ) == tag ) )
			{
				ancestors.push ( parent )
			}
		}
		// move on to the next parent
		parent	= parent.parentNode;
	}
	// return the list
	return ancestors.length ? ancestors : false;
}

/**
 *
 *
 */
ThinkCo.util.Dom.getElementsBySelector = function ( selector )
{
	if ( !document.getElementsByTagName )
		return new Array;

	var getAllChildren = function ( e )
	{
		return e.all ? e.all : e.getElementsByTagName ( '*' );
	}

	// 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 )
			{
				return new Array;	// tag with that ID not found, return false
			}
			// 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];
			tagName		= !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	= tagName == '*' ? getAllChildren ( currentContext [ h ] ) : 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	= tagName == '*' ? getAllChildren ( currentContext [ h ] ) : 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 '~': // Mach 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 ] ) )
				{
					currentontext [ currentContextIndex++ ]	= found [ k ];
				}
			}
			continue; // Skip to next token
		}

		if ( !currentContext [ 0 ] )
		{
			return;
		}

		// 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;
}