//
// Verify function to perform basic check before
// a form is posted. This function checks for required fields and/or
// if fields are numeric
//

var errors="";

function verify(f)
{
	var msg="";
	var empty_fields="";

	for(var i = 0; i < f.length; i++)
	{
		var e = f.elements[i];
		var fieldName = e.desc ? e.desc : e.name;

		if(e.required=="true")
		{
			// check if field is empty
			if(isEmpty(e))
			{
				empty_fields += "\n      * " + fieldName;
				continue;
			}
			else if(e.numeric=="true" && !isNumeric(e))
			{
				errors += "\n - The " + fieldName + " field must be a number.\n";
				continue;
			}
			else if(e.email=="true" && !isValidEmail(e))
			{
				errors += "\n - The " + fieldName + " field contains an invalid e-mail address.\n";
				continue;
			}
			else if(e.maxlen)
			{
				var len = parseInt(e.maxlen);
				var value = e.value;

				if(value.length > len)
				{
					errors += "\n - The " + fieldName + " field cannot exceed " + len + " characters. It currently contains " + value.length + " characters.\n";
					continue;
				}
			}
		}
		else if(e.required=="false" && !isEmpty(e)) //do not validate optional fields if blank
		{
			if(e.numeric=="true" && !isNumeric(e))
			{
				errors += "\n - The " + fieldName + " field must be a number.\n";
				continue;
			}
			else if(e.email=="true" && !isValidEmail(e))
			{
				errors += "\n - The " + fieldName + " field contains an invalid e-mail address.\n";
				continue;
			}
			else if(e.maxlen)
			{
				var len = parseInt(e.maxlen);
				var value = e.value;

				if(value.length > len)
				{
					errors += "\n - The " + fieldName + " field cannot exceed " + len + " characters. It currently contains " + value.length + " characters.\n";
					continue;
				}
			}
		}

		// check if field is zip. Looking for XXXXX-XXXX
		// check if field is phone number. Looking for XXX-XXX-XXXX.
		// check if field is quantity. Spec lists XXXX as the format.

	} //end for

	// if no errors then return true
	if (!empty_fields && !errors) return true;

	msg  = "\n";
	msg += "The form was not submitted for the following reason(s)\n";
	msg += "Please correct the following and re-submit.\n";
	msg += "\n";

	if (empty_fields)
	{
		msg += " - The following required fields are empty:" + empty_fields + "\n";
	}

	msg += errors;
	errors="";
	alert(msg);
	return false;
}

//
// Check if the supplied field is empty
//
function isEmpty(field)
{
	if((field.type == "text") || (field.type == "file") || (field.type == "password") || (field.type == "hidden") || (field.type == "textarea"))
	{
		return (trim(field.value) == "" || field.value == null);
	}
	else if((field.type == "select-one") || (field.type == "select-multiple"))
	{
		return field.options[field.options.selectedIndex].value == "";
	}
	else
	{
		return false;
	}
}

//
// Check if the supplied field contains a numeric value
//
function isNumeric(field)
{
	return !isNaN( parseFloat(field.value) );
}

//
// Check for valid email
//
function isValidEmail(field)
{
	// grab the email address from the form.
	var email = new String(field.value);
	var retval = 0;  // store value returned by String.indexOf.
	var count = 0;   // count of the number of '@' characters.
	var index = 0;   // index from which to start seach

	// look for multiple '@' characters in the address
	while ((retval = email.indexOf("@", index)) != -1)
	{
		count++;
		index = retval + 1;
	}

	// report error if invalid number of '@' characters
	if (count == 1)
	{
		// look for at least 1 dot after the '@' character
		count = 0;
		while ((retval = email.indexOf(".", index)) != -1)
		{
			count++;
			index = retval + 1;
		}
		if (count == 0)
		{
			return false;
		}
		else
		{
			return true;
		}
	}
	else
	{
		return false;
	}
}

//
// Returns a copy of a string without leading spaces
//
function lTrim(str)
{
	var whitespace = new String(" \t\n\r");
	var s = new String(str);
	var count=0;

	while( count < s.length && whitespace.indexOf(s.charAt(count)) != -1 )
	{
		count++;
	}

	return s.substring(count, s.length);
}

//
// Returns a copy of a string without trailing spaces
//
function rTrim(str)
{
	var whitespace = new String(" \t\n\r");
	var s = new String(str);
	var count=s.length-1;

	while( count >= 0 && whitespace.indexOf(s.charAt(count)) != -1 )
	{
		count--;
	}

	return s.substring(0, count+1);
}

//
// Returns a copy of a string without leading or trailing spaces
//
function trim(str)
{
   return rTrim(lTrim(str));
}

//
// Will show or hide an object(span, div, etc..) given its id.
//
function setVisible(id, state)
{
	var element;
	var visible = 'visible';
	var hidden = 'hidden';

	//determine the object based on browser
	if(document.getElementById) // standards
	{
		element = document.getElementById(id).style;
	}
	else if(document.all) // IE4
	{
		element = document.all[id].style;
	}
	else if(document.layers) //N4
	{
		element = document.layers[id];
		visible = 'show';
		hidden = 'hide';
	}

	//hide or show the element
	element.visibility = state ? visible : hidden ;
}

//
// Will set a fields required status amd description.
// For use in Netscape...
//
function setRequired(field, desc)
{
	field.required = "true";
	field.desc = desc;
}


//provides the functionality to check or clear all checkboxes on a form
//uised for selecting or clearing all search collections
function checkAll(fields, value)
{
	for(var i=0; i<fields.length; i++)
	{
		fields[i].checked = value;
	}
}

//validates simple search
function validateSearch(form)
{
	if(trim(form.query.value)=="")
	{
		errors += " - Please enter a search query.";
	}
	
	return verify(form);
}


//validates advanced search
function validateAdvancedSearch(form)
{

	var collectionsChecked = false;
	
	if(trim(form.allwords.value)=="" && trim(form.phrase.value)=="" && trim(form.anywords.value)=="" && trim(form.exclude.value)=="")
	{
		errors += " - Please enter a search query.";
	}
	
	for(var i=0; i<form.elements.length; i++) 
	{
		if(form.elements[i].type=="checkbox")
		{
			if(form.elements[i].checked) collectionsChecked = true;
		}
	}
	
	if(!collectionsChecked)
	{
		errors += "\n - You must choose at least one site to search.";
	}

	return verify(form);
}

//validates feedback form
function validateFeedback(form)
{

	form.name.required='true';
	form.name.desc='Name';
	form.email.required='true';
	form.email.desc='Email Address';
	form.confirmEmail.required='true';
	form.confirmEmail.desc='Confirm Email Address';
	form.comments.required='true';
	form.comments.desc='Comments';
	
	if(form.email.value != form.confirmEmail.value)
	{
		errors += "\n - The confirm email address supplied is incorrect.";
	}
	else if(!isValidEmail(form.email))
	{
		errors += "- Please enter valid email address.";
	}

	return verify(form);
}

function validateSupplyEnquiry(form){
	
	if (form.productServiceCategory.selectedIndex==0)
	{
		form.productServiceCategory.required='true';
		form.productServiceCategory.desc="Company's primary product";	
	}
	

	form.companyName.required='true';
	form.companyName.desc='Company Name';
	form.companyAddress.required='true';
	form.companyAddress.desc='Company Address';
	form.contactName.required='true';
	form.contactName.desc='Contact Name';
	form.jobTitle.required='true';
	form.jobTitle.desc='Job Title';
	form.emailAddress.required='true';
	form.emailAddress.desc='Email Address';
	form.contactAddress.required='true';
	form.contactAddress.desc='Contact Address';
	form.telephone.required='true';
	form.telephone.desc='Telephone Number';
	form.messageSubject.required='true';
	form.messageSubject.desc='Subject of your Message';
	form.messageBody.required='true';
	form.messageBody.desc='Description of your product';
	
	if(!isValidEmail(form.emailAddress))
	{
		errors += "      * Please enter valid email address.";
	}

return verify(form);
}