function showhide(id){

	document.getElementById('tab1').style.display ='none';

	document.getElementById('tab2').style.display ='none';

 	document.getElementById(id).style.display ='block';

}

function updateCounter(maxlimit, field, counter)
{
        var str=field.value;
        str = str.replace(/\r\n/g,"\n");
        
        if (str.length > maxlimit)
        { // if too long...trim it!
                str = str.substring(0, maxlimit);
        if(counter !="")
                counter.innerHTML=maxlimit-str.length;
                field.value=str;
                alert("You have exceeded the maximum limit of "+maxlimit+" characters");
        }
        else
    {
        if(counter !="")
                    counter.innerHTML = maxlimit - str.length;
    }
}

function validate()
{
	var err = '';
	var loggedin = false;
	
	if(document.getElementById('txtauthor') == undefined && document.getElementById('txtemail') == undefined)
		loggedin = true;
	else
		loggedin = false;

	if(!loggedin) {
		var author = trim(document.getElementById('txtauthor').value);
		var email = trim(document.getElementById('txtemail').value);
		
		if(!blankText(author)) {
		err += "Please specify your name.\n";
		}
		else if(validateHTMLData(author)) {
			err += "Please specify valid name.\n";
		}
		if(!blankText(email)) {
			err += "Please specify your email address.\n";
		}
		else if(!emailValidate(email)) {
			err += "Please specify valid email address.\n";
		}
	}
	
	var comment = trim(document.getElementById('txtcomment').value);
	if(!blankText(comment)) {
		err += "Please specify your comments.\n";
	}
	else if(validateHTMLData(comment)) {
		err += "HTML Tags cannot be used in comments.\n";
	}
	

	if(trim(err) == '')
		return true;

	alert(err);
	return false;
}

function blankText(inputText) {
	
	if(inputText == '') {
		return false;
	}
	return true;
}

function emailValidate(email) {
        var emailPattern = /^[a-zA-Z0-9._-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,4}$/;
        return emailPattern.test(email);
}

function validateHTMLData(inputText) {
	var regexp = new RegExp("(<.*>)");
    var flag = false;
    flag = regexp.test(inputText);
    return flag;
}

function trim(inputString)
{
        if (typeof inputString != "string") { return inputString; }

        var temp_str = '';
        temp_str = inputString.replace(/[\s]+/g,"");
        if(temp_str == '')
                return "";

        var retValue = inputString;
        var ch = retValue.substring(0, 1);
        while (ch == " ")
        {
                retValue = retValue.substring(1, retValue.length);
                ch = retValue.substring(0, 1);
        }
        ch = retValue.substring(retValue.length-1, retValue.length);
        while (ch == " ")
        {
                retValue = retValue.substring(0, retValue.length-1);
                ch = retValue.substring(retValue.length-1, retValue.length);
        }
        while (retValue.indexOf("  ") != -1)
        {
          retValue = retValue.substring(0, retValue.indexOf("  ")) + retValue.substring(retValue.indexOf("  ")+1, retValue.length);
        }
        return retValue;
}

function CreateBookmarkLink(url, title) {
	if (window.sidebar) { // Mozilla Firefox Bookmark
		window.sidebar.addPanel(title, url,"");
	} else if( window.external ) { // IE Favorite
		window.external.AddFavorite( url, title); }
	else if(window.opera && window.print) { // Opera Hotlist
		/*
		  var elem = document.createElement('a');
          elem.setAttribute('href',url);
          elem.setAttribute('title',title);
          elem.setAttribute('rel','sidebar');
          elem.click();*/
		alert('Press Ctrl+D to bookmark this page.'); return true; 
	}
}

function show_selected(tabname, q)
{
	switch(tabname) {
		case 'categories':
			if(q == '')
				return true; 
			else 
				show_selected_procedure('nwscont1', q, 'cat');
			break;
		case 'archives':
			if(q == '')
				return true; 
			else 
				show_selected_procedure('nwscont2', q, 'm');
			break;
		default:
			return true;
	}
}

function show_selected_procedure(divName, q, param) {
	objCat = document.getElementById(divName);
	eleCatHref = objCat.getElementsByTagName('a');
	for(cntr=0;cntr < eleCatHref.length; cntr++) {
		var tmpUrl = eleCatHref[cntr].href.split('?');
		var tmpQuery = param + '=' + q;
		if(tmpUrl[1] == tmpQuery) {
			eleCatHref[cntr].style.backgroundColor = "#DADADA";
			eleCatHref[cntr].style.color = "#000000";
		}
	}
}