function IsHttp(StrValue, strMsg)
	{

		var reg_exp1 = new RegExp("http://")
		var reg_exp2 = new RegExp("https://")
		var reg_exp3 = new RegExp("ftp://")

		if ((StrValue.search(reg_exp1) != 0) && (StrValue.search(reg_exp2) != 0) && (StrValue.search(reg_exp3) != 0))
		{ 
			if (fCheck)
			{                     
				alert(strMsg)
				fCheck = false
			}
		}
	}


	function testUrl(which_field)
	{
		fCheck = true
		// Which_field is compiled on the page as this.form.field_name
		ValueCheck(which_field.value, "", "You must first enter a url to test");
		IsHttp(which_field.value, "Your url must be prefixed by one of the following protocols in order to link correctly\n\nA. 'http://'\nB. 'https://'\nC. 'ftp://'");

		if (fCheck)
		{
			window.open(which_field.value , "displaywindow", "width=400,height=300,toolbar=no,scrollbars=yes,resizable=yes,menubar=no,status=no,directories=no,location=yes");
		}
	}


	function PhoneNumCheck(strFieldValue, FieldName)
	{

		var PhonePat1 = /\d{2}\s\d{4}\s\d{4}/ 		// XX XXXX XXXX
		var PhonePat2 = /\d{4}\s\d{3}\s\d{3}/ 		// XXXX XXX XXX
		var PhonePat3 = /\d{2}\s\d{2}\s\d{2}/		// XX XX XX

		// if (str is blank or ((is 12 digit matching XX XXXX XXXX) OR (is 12 digit matching XXXX XXX XXX) OR (is 8 digit matching XX XX XX)))

	 	if ((strFieldValue == "") || ((strFieldValue.search(PhonePat1) == 0) && (strFieldValue.length == 12)) || ((strFieldValue.search(PhonePat2) == 0) && (strFieldValue.length == 12)) || ((strFieldValue.search(PhonePat3) == 0) && (strFieldValue.length == 8)))
		{    
			return
		} else {                  
			if (fCheck)
			{
				alert(FieldName + " must: \n\nA. contain numbers and spaces only\nB. conform to one of the following patterns:\n\n1. 00 0000 0000\n2. 0000 000 000\n3. 000 000")
				fCheck = false
			}
		}
	}


	function EmailCheck(emailStr) {

	if ((fCheck != false) && (emailStr !="")) {
		fCheck = false

		var emailPat		= /^(.+)@(.+)$/
		var specialChars	= "\\(\\)<>@,;:\\\\\\\"\\.\\[\\]"
		var validChars		= "\[^\\s" + specialChars + "\]"
		var quotedUser		= "(\"[^\"]*\")"
		var ipDomainPat		= /^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/
		var atom			= validChars + '+'
		var word			= "(" + atom + "|" + quotedUser + ")"
		var userPat 		= new RegExp("^" + word + "(\\." + word + ")*$")
		var domainPat		= new RegExp("^" + atom + "(\\." + atom +")*$")

		var matchArray=emailStr.match(emailPat)
		if (matchArray==null) {
			alert("email address seems incorrect\ncheck that it contains one '@' and at least one full stop character")
			return false
		}

		var user 	= matchArray[1]
		var domain 	= matchArray[2]
		if (user.match(userPat)==null) {
	    	// user is not valid
		    alert("email address seems incorrect\nthe username portion doesn't seem to be valid")
		    return false
		}

		var IPArray = domain.match(ipDomainPat)
		if (IPArray!=null) {
		    // this is an IP address
			  for (var i=1;i<=4;i++) {
			    if (IPArray[i]>255) {
			        alert("email address seems incorrect\ndestination IP address is invalid")
				return false
			    }
		    }
		    return true
		}

		var domainArray = domain.match(domainPat)
		if (domainArray==null) {
			alert("email address seems incorrect\nThe domain name doesn't seem to be valid.")
		    return false
		}

		var atomPat = new RegExp(atom,"g")
		var domArr 	= domain.match(atomPat)
		var len		= domArr.length
		if (domArr[domArr.length-1].length<2 || domArr[domArr.length-1].length>3) {
		   // the address must end in a two letter or three letter word.
		   alert("The address must end in a three letter domain, or two letter country code")
		   return false
		}

		if (len<2) {
		   alert("This address appears to be missing a hostname")
		   return false
		}

		fCheck = true
		return true;
		}
	}

	function Validate_date(date_field)
	{
		if (fCheck){

			var my_arr 		= date_field.split("/");
			var format_msg 	= "\n\ndates must be in the format DD/MM/YYYY"

			if (my_arr.length != 3){
				if (my_arr.length == 1){
					alert("the date string provided did not contain any slashes [/] which are used to seperate day/month/year values\nthe date was unable to be validated");
				} else {
					alert("the date string provided contained " + (my_arr.length - 1) + " slashes [/] instead of 2\nthe date was unable to be validated");
				}
				fCheck = false;
				return;
			} 

			// CONFIRM THAT PROVIDED VALUES ARE ALL INTEGERS
			for(var m = 0; m < my_arr.length; m++){
				if (isNaN(my_arr[m])){
					alert("the date string must contain only numbers, please change '" + my_arr[m] + "'");
					fCheck = false;
					return;
				}
			}

			// initialise
			this_day	= my_arr[0];
			this_month	= my_arr[1];
			this_year	= my_arr[2];

			month_arr 	= ['JAN','FEB','MAR','APR','MAY','JUN','JUL','AUG','SEP','OCT','NOV','DEC']

			if (this_year.length != 4){
				alert("please enter a four digit year" + format_msg);
				fCheck = false;
				return;
			}

			if (this_month > 12 || this_month < 1){
				alert("there can only be 12 months in a year, please use a number from 1 - 12" + format_msg);
				fCheck = false;
				return;
			}

			if (this_day < 1){
				alert("the day value must be a number greater than 0" + format_msg);
				fCheck = false;
				return;
			}

			if (this_month == 2){
				if (this_year % 4 == 0 && (this_year % 100 != 0 || this_year % 400 == 0)){
					if (this_day > 29){
						alert("there can only be 29 days in " + month_arr[this_month-1] + " on a leap year");
						fCheck = false;
						return;
					}
				} else {
					if (this_day > 28){
						alert("there can only be 28 days in " + month_arr[this_month-1]);
						fCheck = false;
						return;
					}
				}	
			}

			if ( ( (this_month == 4) || (this_month == 6) || (this_month == 9) || (this_month == 11) ) && (this_day > 30) ) {
				alert("there can only be 30 days in " + month_arr[this_month-1]);
				fCheck = false;
				return;
			}

			if (this_day > 31){
				alert("there can not be more that 31 days in " + month_arr[this_month-1]);
				fCheck = false;
				return;
			}		
		}

	}

	function Validate_datediff(start_date_name, start_date_value, end_date_name, end_date_value, error_msg){

		Validate_date(start_date_value);
		Validate_date(end_date_value);

		if (fCheck) {

			var start_arr 		= start_date_value.split("/");
			var end_arr 		= end_date_value.split("/");

			// initialise
			var is_error = 1
			var error_str = ""

			start_day		= parseInt(start_arr[0],10);
			start_month		= parseInt(start_arr[1],10);
			start_year		= parseInt(start_arr[2],10);

			end_day			= parseInt(end_arr[0],10);
			end_month		= parseInt(end_arr[1],10);
			end_year		= parseInt(end_arr[2],10);

			if (start_year > end_year){
				error_str = "year"
			} else {
				if ((start_month > end_month) && (start_year == end_year)){
					error_str = "month"
				} else {
					if ((start_day > end_day) && (start_month == end_month) && (start_year == end_year)){
						error_str = "day"
					} else {
						is_error = 0
					}
				}
			}
			if (is_error == 1){
				alert(error_msg + "the selected " + start_date_name + " (" + start_date_value + ") occurs after " + end_date_name + " (" + end_date_value + ")");
				//alert(error_msg + "the selected " + start_date_name + " (" + start_date_value + ") occurs after " + end_date_name + " (" + end_date_value + ") \nthe offending value is the " + error_str + " field");
				fCheck = false;
				return;
			}
		}
	}


	function CheckRanking(which_form, field_name, exclusion_str) {

		loop_count = 0
		fCheck = true

		with (window.document) {
			this_value = which_form.elements.length;
			final_array = new Array();

			for ( i=0; i < this_value; i++ ) {
				item_name = which_form.elements[i].name;

				if (item_name == field_name) {

					for(var m = 0; m < which_form.elements[i].options.length; m++){
						if(which_form.elements[i].options[m].selected){
							item_value = which_form.elements[i].options[m].value
							//	alert("item_value = " + item_value);
						}
					}

					tempstr = item_value;
					finalstr = tempstr.split("_");

					if (finalstr[1] != exclusion_str) {

						final_array[loop_count] = finalstr[1];
    
						for ( n=0; n < loop_count; n++) {
							if (fCheck){
	
								if (final_array[n] == finalstr[1]) {
									fCheck = false;
									alert("there is more than one item ranked in position " + finalstr[1] + "\nplease make sure that all rankings are unique and try again");
									//	alert("failed test\n" + final_array[n] + " = " + finalstr[1]);
								}
								//else {
									//	alert("passed test\n" + final_array[n] + " != " + finalstr[1]);
								//}
							}
						}
						loop_count++;

					} // finalstr[1] is not equal to the exclusion_str value [999]
				}
			}
		}
		if (fCheck) {
			which_form.submit()
		}
	}

	function NullCheck(StringValue, strMsg) {
		if ( Trim( StringValue) == '') {
				alert(strMsg);
				return false;
		}
		return true;
	}

	function LTrim(str) {

		var whitespace = new String(" \t\n\r");
		var s = new String(str);

		if (whitespace.indexOf(s.charAt(0)) != -1) {
			var j=0, i = s.length;
			while (j < i && whitespace.indexOf(s.charAt(j)) != -1)
				j++;
			s = s.substring(j, i);
		}
		return s;
	}

	function RTrim(str) {
		var whitespace = new String(" \t\n\r");
		var s = new String(str);
		if (whitespace.indexOf(s.charAt(s.length-1)) != -1) {
			var i = s.length - 1;       // Get length of string
			while (i >= 0 && whitespace.indexOf(s.charAt(i)) != -1)
				i--;
			s = s.substring(0, i+1);
		}
		return s;
	}
	
	function Trim(str) {
		return RTrim(LTrim(str));
	}

	function AlphaNumCheck(fieldvalue,FieldMessage) {
		var valid = "0123456789abcdefghijklmnopqrstuvwxyz "
		var temp;
		var ok;
		ok = true;
		if (fCheck) {
			for (var i=0; i<fieldvalue.length; i++)  {
				temp = "" + fieldvalue.substring(i, i+1);
				 if (valid.indexOf(temp.toLowerCase()) == "-1") ok = false;
			   }
			if (ok == false)  {
				   alert(FieldMessage);
				   fCheck = false;
			}
		}
	}

			
	function InvalidCharacterCheck(fieldValue, checkValue, fieldMessage)
	{
		if (fieldValue.indexOf(checkValue) != -1)
		{
			if (fCheck)
			{                    
				alert(fieldMessage);
				fCheck = false;
			}
		}
	}


	function PhoneNumberCheck(StrValue, sErrorMsg)
	{
		var ValidCharacters = "0123456789 ";
		var character;
		var bValid = true;

		for (var i=0; i<StrValue.length; i++)
		{
			character = StrValue.substring(i, i+1);
			
			if (ValidCharacters.indexOf(character) == "-1")
			{
				bValid = false;
			}
		}

		if (!bValid)
		{                     
			alert(sErrorMsg);
			fCheck = false;
		}
	}


	function IsHttpExists(StrValue)
	{
		var reg_exp1 = new RegExp("http://")
		var reg_exp2 = new RegExp("https://")
		var reg_exp3 = new RegExp("ftp://")

		if ((StrValue.search(reg_exp1) == -1) && (StrValue.search(reg_exp2) == -1) && (StrValue.search(reg_exp3) == -1))
		{
			bHttpStrExists = false
		} else {
			bHttpStrExists = true
		}
	}


	function CheckValidUrl(field)
	{
		fCheck = true;
		bHttpStrExists = false;

		ValueCheck(field, "", "You must first enter a url to test");
		IsHttpExists(field);
		
		if (fCheck)
		{
			if (bHttpStrExists)
			{
				window.open(field, "displaywindow", "width=400,height=300,toolbar=no,scrollbars=yes,resizable=yes,menubar=no,status=no,directories=no,location=yes");
			} else {
				window.open("http://" + field, "displaywindow", "width=400,height=300,toolbar=no,scrollbars=yes,resizable=yes,menubar=no,status=no,directories=no,location=yes");
			}
		}
	}