// JavaScript Document

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 a value for the "' + fieldLabel +'" field.' );
		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;
}