/**
 * A collection of DOM manipulation methods.
 *
 * Requires:
 *	Arrays.js
 */

Arrays.augmentArrayPrototype();

var DOM =
{
	buildElementGroups: function(inDocument,inGroupDefinitions,inPrefix,inSeparator,inDepth)
	{
		var theGroup;
		var theElement;
		var theIndex;

		if (inSeparator === undefined)
			inSeparator = ".";
		if (inPrefix === undefined)
			inPrefix = "";
		if (inDepth === undefined)
			inDepth = 0;
		theGroup = new Array();
		if (inGroupDefinitions[inDepth] !== null)
			theIndex = inGroupDefinitions[inDepth].startIndex;
		if (theIndex === undefined)
			theIndex = 1;

		for (;;)
		{
			if (inDepth === inGroupDefinitions.length - 1)
				theElement = inDocument.getElementById(inPrefix + theIndex);
			else
			{
				theElement = DOM.buildElementGroups(
					inDocument,
					inGroupDefinitions,
					inPrefix + theIndex + inSeparator,
					inSeparator,
					inDepth + 1);
			}

			if (theElement == null)
				break;

			theGroup[theGroup.length] = theElement;
			theIndex++;
		}

		if (theGroup.length == 0)
			return (null);

		if (inGroupDefinitions[inDepth] !== null && inGroupDefinitions[inDepth].extractor !== undefined)
			theGroup = inGroupDefinitions[inDepth].extractor(theGroup);

		return (theGroup);
	},


	buildElementGroupsFromChildren: function(inElement,inExtractor)
	{
		var i;
		var max;
		var theList;
		var theElement;

		theList = new Array();
		inElement = inElement.childNodes;
		for (i = 0,max = inElement.length; i < max; i++)
		{
			theElement = inElement.item(i);
			if (theElement instanceof HTMLElement)
				theList[theList.length] = inExtractor(theElement);
		}
		return (theList);
	},


	extractArrayElement: function(inArray,inIndex)
	{
		return (inArray[inIndex]);
	},


	objectWrap: function(inObject,inPropertyName)
	{
		var theResult;

		theResult = new Object();
		theResult[inPropertyName] = inObject;

		return (theResult);
	},


	extractPropertiesFromAttributes: function(inElement,inObject,inPropertyNames,inPropertyTransformers)
	{
		var i;
		var theName;
		var theValue;

		if (inPropertyNames)
		{
			for (i = 0; i < inPropertyNames.length; i++)
			{
				theName = inPropertyNames[i];
				theValue = inElement.getAttribute(theName).value;
				if (inPropertyTransformers && inPropertyTransformers.getProperty(theName))
					theValue = inPropertyTransformers.getProperty(theName)(theValue);
				inObject[theName] = theValue;
			}
		}
		else
		{
			var theAttributes;
			var theAttribute;

			for (theAttributes = inElement.attributes,i = 0; i < theAttributes.length; i++)
			{
				theAttribute = theAttributes.item(i);
				if (theAttribute.specified)
				{
					// Browsers are inconsistent in case preservation for attribute names
					theName = theAttribute.name.toLowerCase();
					theValue = theAttribute.value;
					if (inPropertyTransformers && inPropertyTransformers.getProperty(theName))
						theValue = inPropertyTransformers.getProperty(theName)(theValue);
					inObject[theName] = theValue;
				}
			}
		}
		return (inObject);
	},


	convertToNumber: function(inValue,inEmptyValue,inFailureValue)
	{
		var theNumber;

		try
		{
			if (inValue === null || inValue === undefined)
			{
				if (inEmptyValue !== undefined)
					return (inEmptyValue);
				throw ("attempted to convert null or undefined to number")
			}

			theNumber = eval(inValue);
			if (typeof theNumber != 'number')
			{
				if (inFailureValue !== undefined)
					return (inFailureValue);
				throw ("attempted to convert '" + inValue + "' to number");
			}

			return (theNumber);
		}
		catch (theError)
		{
			if (inFailureValue !== undefined)
				return (inFailureValue);
			throw (theError);
		}
	},


	extractPropertiesFromFirstElementInGroup: function(inElementGroup,inElementGroupPropertyName,inPropertyNames,inPropertyTransformers)
	{
		return (DOM.extractPropertiesFromAttributes(
			inElementGroup[0],
			DOM.objectWrap(inElementGroup,inElementGroupPropertyName),
			inPropertyNames,
			inPropertyTransformers));
	},


	extractPropertiesFromFormElements: function(inDocument,inIDs)
	{
		var i;
		var theResult;
		var theElement;

		// todo: eventually this should populate the result in exactly the same way as a submit, i.e. it should
		// handle radio buttons and check boxes in the same way.  It should also handle selects.
		theResult = new Properties();
		for (i = 0; i < inIDs.length; i++)
		{
			theElement = inDocument.getElementById(inIDs[i]);
			if (theElement === null)
				theResult.setProperty(inIDs[i],null);
			else
				theResult.setProperty(inIDs[i],theElement.value);
		}

		return (theResult);
	},


	replaceElements: function(inOldElements,inNewElements)
	{
		var theOldIndex;
		var i;

		for (i = 0; i < inOldElements.length; i++)
		{
			if (inOldElements[i] !== inNewElements[i])
			{
				if (inNewElements[i].parentNode != null)
				{
					theOldIndex = inOldElements.indexOf(inNewElements[i]);
					if (theOldIndex >= 0)
					{
						thePlaceholder = inNewElements[i].ownerDocument.createComment("");
						inNewElements[i].parentNode.replaceChild(thePlaceholder,inNewElements[i]);
						inOldElements[theOldIndex] = thePlaceholder;
					}
				}
				inOldElements[i].parentNode.replaceChild(inNewElements[i],inOldElements[i])
			}
		}
	},


	setDisplayStyle: function(inElements,inDisplay)
	{
		var i;

		for (i = 0; i < inElements.length; i++)
			inElements[i].style.display = inDisplay;
	},


	getElementById: function(inID)
	{
		if (document.getElementById)
			return (document.getElementById(inID));
		else if (document.all)
			return (document.all[inID]);
		else
			return (null);
	},


	addClass: function(inElement,inClass)
	{
		DOM.removeClass(inElement,inClass);
		inElement.className += " " + inClass;
	},


	removeClass: function(inElement,inClass)
	{
		inElement.className = inElement.className.replace(new RegExp(" " + inClass + "\\b"),"");
	},


	walkTheDOM : function(inNode, inFunction)
	{
		inFunction(inNode);
		inNode = inNode.firstChild;
		while (inNode) {
			walkTheDOM(inNode, func);
			inNode = inNode.nextSibling;
		}
	},


	getElementsByClassName : function(inClassName, inNode)
	{
		var theResults = [];
		var processNode = function (inNodeToCompare)
		{
			var theClassNames, theClassNameProperty = inNodeToCompare.className, i;
			if (theClassNameProperty)
			{
				theClassNames = theClassNameProperty.split(' ');
				for (i = 0; i < theClassNames.length; i++)
				{
					if (theClassNames[i] === inClassName)
					{
						theResults.push(inNodeToCompare);
						break;
					}
				}
			}
		};

		DOM.walkTheDOM(inNode || document.body, processNode)

		return theResults;
	},

	processElementByClassName : function(inClassName, inFunction, inNode)
	{
		var theResults = DOM.getElementsByClassName(inclassName, inNode);
		for (var i = 0; i < theResults.length; i++)
			inFunction(theResults[i]);
	}

};