// $Header: $
//////////////////////////////////////////////////////////////////////

/*
-------------------  VALIDATION ROUTINES  ------------------

validRequired(formField, fieldLabel) -- checks for a field being empty

validEmail(formField, fieldLabel, required) -- checks for a correctly formatted email address

validNum(formField, fieldLabel, required) -- checks for a valid number (a string where all the characters are digits)

validInt(formField, fieldLabel, required) -- checks for a number (integer) that can be 

correctly parsed with the function parseInt

validDate(formField, fieldLabel, required) -- checks for a correctly formatted date 

  formField -- the document reference to your form field (e.g., myform.fieldName)
  fieldLabel -- the user friendly string that you want the error message to refer to your field by
  required -- whether the field is required to be filled in by the user (true/false) 

validatePositiveInteger(s) -- obvious

validateMoney(s)

validatePercent(s)

-------------------  FORMATTING ROUTINES  ------------------

formatMoney(s)


--------------  SAMPLE USAGE  -------------------

function validateForm(theForm)
{
	// Customize these calls for your form

	if (!validRequired(theForm.fullname,"Name"))
		return false;

	if (!validEmail(theForm.email,"Email Address",true))
		return false;

	if (!validDate(theForm.available,"Date Available",true))
		return false;

	if (!validNum(theForm.yearsexperience,"Years Experience",true))
		return false;
	
	return true;
}

*/

function isEmailAddr(email)
{
  var result = false;
  var theStr = new String(email);
  var index = theStr.indexOf("@");
  if (index > 0)
  {
    var pindex = theStr.indexOf(".",index);
    if ((pindex > index+1) && (theStr.length > pindex+1))
	result = true;
  }
  return result;
}

function validRequired(formField,fieldLabel)
{
	var result = true;
	
	if (formField.value == "")
	{
		alert('Please enter "' + fieldLabel +'".');
		formField.focus();
		result = false;
	}
	
	return result;
}

function allDigits(str)
{
	return inValidCharSet(str,"0123456789");
}

function inValidCharSet(str,charset)
{
	var result = true;

	// Note: doesn't use regular expressions to avoid early Mac browser bugs	
	for (var i=0;i<str.length;i++)
		if (charset.indexOf(str.substr(i,1))<0)
		{
			result = false;
			break;
		}
	
	return result;
}

function validEmail(formField,fieldLabel,required)
{
	var result = true;
	
	if (required && !validRequired(formField,fieldLabel))
		result = false;

	if (result && ((formField.value.length < 3) || !isEmailAddr(formField.value)) )
	{
		alert("Please enter a complete email address in the form: yourname@yourdomain.com");
		formField.focus();
		result = false;
	}
   
  return result;

}

function validNum(formField,fieldLabel,required)
{
	var result = true;

	if (required && !validRequired(formField,fieldLabel))
		result = false;
  
 	if (result)
 	{
 		if (!allDigits(formField.value))
 		{
 			alert('Please enter a number for the "' + fieldLabel +'" field.');
			formField.focus();		
			result = false;
		}
	} 
	
	return result;
}


function validInt(formField,fieldLabel,required)
{
	var result = true;

	if (required && !validRequired(formField,fieldLabel))
		result = false;
  
 	if (result)
 	{
 		var num = parseInt(formField.value,10);
 		if (isNaN(num))
 		{
 			alert('Please enter a number for the "' + fieldLabel +'" field.');
			formField.focus();		
			result = false;
		}
	} 
	
	return result;
}


function validDate(formField,fieldLabel,required)
{
	var result = true;

	if (required && !validRequired(formField,fieldLabel))
		result = false;
  
 	if (result)
 	{
 		var elems = formField.value.split("/");
 		
 		result = (elems.length == 3); // should be three components
 		
 		if (result)
 		{
 			var month = parseInt(elems[0],10);
  			var day = parseInt(elems[1],10);
 			var year = parseInt(elems[2],10);
			result = allDigits(elems[0]) && (month > 0) && (month < 13) &&
					 allDigits(elems[1]) && (day > 0) && (day < 32) &&
					 allDigits(elems[2]) && ((elems[2].length == 2) || (elems[2].length == 4));
 		}
 		
  		if (!result)
 		{
 			alert('Please enter a date in the format MM/DD/YYYY for the "' + fieldLabel +'" field.');
			formField.focus();		
		}
	} 
	
	return result;
}

//---------------------------------------------
// Returns: true if valid, false if not valid.
//---------------------------------------------
function validatePositiveInteger(s)
{
	if(s.length == 0)
		return false;
	
	for(var i=0; i<s.length; ++i)
	{
		if("0123456789".indexOf(s.charAt(i)) < 0)
			return false;
	}
	return true;
}

//---------------------------------------------
// Returns: true if valid, false if not valid.
//---------------------------------------------
function validateMoney(s)
{
	s = stripDollarSign(s);
	return validateDecimal(s);
}

//---------------------------------------------
// Returns: true if valid, false if not valid.
//---------------------------------------------
function validatePercent(s)
{
	s = stripPercentSign(s);
	return validateDecimal(s);
}

//---------------------------------------------
// Returns: true if valid, false if not valid.
//---------------------------------------------
function validateDecimal(s)
{
	if(s.length == 0)
		return false;
		
	if(s == "." || s == "-" || s == "+")
		return false;

	var bDP = false;
	for(var i=0; i<s.length; ++i)
	{
		if(s.charAt(i) == "+" && i > 0)
			return false;
		else if(s.charAt(i) == "-" && i > 0)
			return false;
		else if(s.charAt(i) == "." && bDP)
			return false;
		else if(s.charAt(i) == ".")
			bDP=true;
		else if("+0123456789-".indexOf(s.charAt(i)) < 0)
			return false;
	}
	return true;
}

function formatMoney(s)
{	
	s = stripDollarSign(s);
	
	if(s == "")
		s = "0";
	
	var p = s.indexOf(".");
	if(p < 0) 
	{
		// No decimal present.
		s += ".00";
		p = s.indexOf(".");
	}
	if(p == 0)
	{
		// Decimal at position 0
		s = "0" + s;
		p = s.indexOf(".");
	}
	s += (p == s.length-1) ? "00" : (p == s.length-2) ? "0" : "";
	return "$" + s;
}

function formatPercent(s)
{	
	s = stripPercentSign(s);
	
	if(s == "")
		s = "0";
	
	var p = s.indexOf(".");
	if(p < 0) 
	{
		// No decimal present.
		s += ".0";
		p = s.indexOf(".");
	}
	if(p == 0)
	{
		// Decimal at position 0
		s = "0" + s;
		p = s.indexOf(".");
	}
	s += (p == s.length-1) ? "0" : "";
	return s + "%";
}

function stripDollarSign(s)
{
	var p = s.indexOf("$");
	return s.substring(p+1);
}

function stripPercentSign(s)
{
	var p = s.indexOf("%");
	if(p > -1)
		return s.substring(0,p);
	else
		return s;
}