//checkGroups works for radio buttons or checkbox groups (checkboxes that have the same id)
function checkGroups (form, fieldName) {
   var valid = 0;
  
  if (form[fieldName].length) //multiple radio button answers
  {
    for (var i = 0; i < form[fieldName].length; i++) 
	{
      if (form[fieldName][i].checked)
      	{
	  	  valid = 1;
		}
	}
	  
  }
  else  //single radio button answer
  {
  	if (form[fieldName].checked)
	{
	  	  valid = 1;
	}
  }
    
    return valid;
}

function validate()
{
	err = "";
	
			
	//First Name
	if(document.main.firstName.value == "")
	{
		err += "Please enter your first name.\n";
	}
	
	//Last Name
	if(document.main.lastName.value == "")
	{
		err += "Please enter your last name.\n";
	}
		
		
	email = document.main.email.value;
	
	if(email == "")
	{
		err += "Please enter an email address.\n";
	}
	else
	{  
		rx=new RegExp("^[\\w\.=-]+@[\\w\\.-]+\\.[a-zA-Z]{2,4}$");
		if(!rx.test(email))
		{
			err += "Please enter a valid email address.\n";
		}
	}
	
	if(document.main.address1.value == "")
	{
		err += "Please enter your address.\n";
	}
	
	if(document.main.city.value == "")
	{
		err += "Please enter your city.\n";
	}
		
	if(document.main.state.selectedIndex == 0)
	{
		err += "Please select your state.\n";
	} 
	//phone
	if(document.main.phone1.value == "")
	{
		err += "Please enter the area code for your phone number.\n";
	}
	if(document.main.phone2.value == "")
	{
		err += "Please enter your phone number.\n";
	}
	/*
	if(document.main.phone3.value == "")
	{
		err += "Please enter the extension for your phone number.\n";
	}*/
	
	if(document.main.zip.value == ""  || document.main.zip.value.length < 5 )
	{
		err += 'Please enter your ZIP code in proper format.\n';
	}	
			
	
	rbValid = checkGroups(document.main, 'rbWhoResponded');
	if (rbValid == 0)
	{
		err += "Please indicate your interest in Zapwater Communications.\n"
	}
	
	if(err != "")
	{
		alert("The following errors have occurred:\n\n" + err );
		
	}
	document.formErrors_returnValue = (err == "");
}