function trim(str) {
	return str.replace(/^\s*|\s*$/g,"");
}

function isRadioSelected(radioGroup) {
	if (!radioGroup.length) {
		return radioGroup.checked;
	}
	for (var i = 0; i < radioGroup.length; i++) {
		if (radioGroup[i].checked) {
			return true;
		}
	}
	return false;
}

function isCheckboxSelected(checkboxGroup) {
	return isRadioSelected(checkboxGroup);
}

function isEmpty(field) {
	if (field.value == '') {
		return true;
	} else {
		return false;
	}
}

function isEmail(strValue) {
	var objRegExp = /^[-+_a-z0-9.]+@[-a-z0-9.]+/i;

	//check for valid email
	return objRegExp.test(strValue);
}

function isInteger(strValue) {
	var objRegExp  = /(^-?\d+$)/;

	//check for integer characters
	return objRegExp.test(strValue);
}

function isNumeric(strValue) {
	var objRegExp = /(^-?\d+\.\d*$)|(^-?\d+$)|(^-?\.\d+$)/;

	//check for numeric characters
	return objRegExp.test(strValue);
}

function isAlpha(strValue) {
	var objRegExp = /^[a-z]+$/i;
	return objRegExp.test(strValue);
}

function isAlphaNumeric(strValue) {
	var objRegExp = /^[a-z0-9]+$/i;
	return objRegExp.test(strValue);
}

function match(strValue, strMatchPattern) {
	var objRegExp = new RegExp( strMatchPattern);

	//check if string matches pattern
	return objRegExp.test(strValue);
}

function removeCommas(strValue) {
	var objRegExp = /,/g; //search for commas globally

	//replace all matches with empty strings
	return strValue.replace(objRegExp,'');
}

function removeCurrency(strValue) {
	var objRegExp = /\(/;
	var strMinus = '';

	//check if negative
	if(objRegExp.test(strValue)){
		strMinus = '-';
	}

	objRegExp = /\)|\(|[,]/g;
	strValue = strValue.replace(objRegExp,'');
	if(strValue.indexOf('$') >= 0){
		strValue = strValue.substring(1, strValue.length);
	}
	return strMinus + strValue;
}

function isCurrency(strValue) {
	return isNumeric(removeCurrency(strValue));
}

function removeCharacters(strValue, strMatchPattern) {
	var objRegExp =  new RegExp( strMatchPattern, 'gi' );

	//replace passed pattern matches with blanks
	return strValue.replace(objRegExp,'');
}

function clearErrors(form_name) {
	var form = document.forms[form_name];
	var labels = form.getElementsByTagName('th');
	for (var i = 0; i < labels.length; i++) {
		if (labels[i].className == 'error') {
			labels[i].className = 'label';
		}
	}
	
	// clear error message
	document.getElementById(form_name + '_error_list').innerHTML = '';
}

var currentGroup = null;

function startGroup(form_name, name, label) {
	var groupHeading = document.createElement('li');
	groupHeading.innerHTML = label + ' has the following errors:';
	document.getElementById(form_name + '_error_list').appendChild(groupHeading);
	currentGroup = document.createElement('ul');	
}

function endGroup(form_name, name) {
	if (currentGroup.childNodes.length > 1) {
		document.getElementById(form_name + '_error_list').appendChild(currentGroup);
		var labelElm = document.getElementById('label_' + name);
		if (labelElm && labelElm.className) {
			labelElm.className = 'error';
		}
	}
	currentGroup = null;
}

function error(form_name, label, errorMessage) {
	document.getElementById(form_name + '_error_hint').style.display = 'inline';
	var labelElm = document.getElementById('label_' + label);
	if (labelElm) {
		labelElm.className = 'error';
	}
	
	// append error message
	var msg = document.createElement('li');
	msg.innerHTML = errorMessage;
	if (currentGroup != null) {
		currentGroup.appendChild(msg);		
	} else {
		document.getElementById(form_name + '_error_list').appendChild(msg);
	}
}

function isError(form_name, label, condition, errorMessage) {
	if (condition) {
		error(form_name, label, errorMessage);
		return true;
	}
	return false;
}