/*

Text marker code 

Ashok Hariharan

*/





/*helper function , just does search & replace */



function replaceMe(str, phrase, chg) {

var pattern = new RegExp (phrase ,'ig');

return str.replace( pattern, chg);

}





/*helper function , gets innerHtml of a layer */

/*code ripped from ppk : http://xs4all.nsl/~ppk/js/ */

function getLayerHtml(id)

{

	var inHtml = new String('');

	if (document.getElementById)

	{

		x = document.getElementById(id);

		inHtml = x.innerHTML;

	}

	else

	 if (document.all)

	{

		x = document.all[id];

		inHtml = x.innerHTML;

	}

	return inHtml;

}



/*helper function , sets the innerHtml of a layer */

/*code ripped from ppk : http://xs4all.nsl/~ppk/js/ */

function setLayerHtml(text,id)

{

	if (document.getElementById)

	{

		elemObj = document.getElementById(id);

		elemObj.innerHTML = text;

	}

	else if (document.all)

	{

		elemObj = document.all[id];

		elemObj.innerHTML = text;

	}

	/*

	this is ns4 compatible code ...

	*/

	/*

	else if (document.layers)

	{

		x = document.layers[id];

		text2 = '<P CLASS="testclass">' + text + '</P>;';

		x.document.open();

		x.document.write(text2);

		x.document.close();

	}

	*/

}



/*main marker function*/

function markText(txtKeyword, inputHtml) 

{

           var re; 						/*regex object*/

           var varMatches; 					/*matches array*/

           var outHtml; 					/*output html*/

           var replaceText;

           replaceText = '<span style="background-color:yellow;color:red;font-weight:bold;">'+txtKeyword+ '</span>';

	   re=new RegExp("(\<[^>][^<]*\>)([^<]*)","g");	/*create non-greedy regex match*/	   



	   /*

	   note : 

	   in 99% of cases <[^>]*\>)([^<]*) 

	   should also work , i did have the rare case where some invisible 

	   characters caused this to crap out ....

	   */



	   outHtml=new String('');				/*init html string*/

	   while ((varMatches = re.exec(inputHtml)) != null)		/*exec sequentially to apply span tags*/

	   {

		 outHtml+=varMatches[1]; 	/*html tag part*/

		 outHtml+=replaceMe(varMatches[2], txtKeyword, replaceText); 

	   }

	   return outHtml;

}





function main()

{

	/*get the href of the current page*/

	var ref = document.location.href;

	/*this stores the name of the query string that contains the keyword to be higlighted*/

	var hiliteUrl = new String('hilite');

	/*array for temp. use*/

	var arr;

	/*stores the keywords that are to be highlighted*/

	var hiliteText;

	



	/*split into array using & as a separator*/

	arr = ref.split('&');

	for (var i=0 ; i < arr.length; i++)

	{

		var idx = arr[i].indexOf(hiliteUrl + '=');	

		if (idx != -1)

		{

			/*unescape the string to be on the safe side*/

			hiliteText =  unescape(arr[i].substring(idx+hiliteUrl.length+1));

		

			/*replace any + character which might have been used to pad a space, with a space */

			hiliteText = replaceMe(hiliteText, '\\+', ' ');

		

			if (hiliteText.length != 0)

			{

				/*we have successfully parsed out the url now pass it to the highlight func.*/

				var inHtml;

				var outHtml;

				/*get the innerHtml content from within the div*/

				inHtml = '<em></em>'+getLayerHtml('contentdiv');		

				/*run the hilite function to hilite stuff*/

				outHtml = markText(hiliteText, inHtml);

				/*write the hilited stuff back to the div*/

				setLayerHtml(outHtml,'contentdiv');

			}

			return;

		}

	}

}



function onLoad()

{

/*1 - we parse out the hilite= querystring value */

main();

return;

}