///////////////////////////////////////////
// Form validation for book page
///////////////////////////////////////////
function validate(myForm){

	// Set background color for all form fields to default white
	document.getElementById('FirstName').className = " ";
	document.getElementById('LastName').className = " ";
	document.getElementById('Email').className = "";


	//Set the default error message
	errmsg = "The following fields are required:\n\n";
	if (myForm.FirstName.value=="" || myForm.FirstName.value=="First Name*"){
		errmsg += "Your first name\n";
		thisClass = document.getElementById('FirstName').className;
		document.getElementById('FirstName').className = thisClass + " error";
	}

	if (myForm.LastName.value=="" || myForm.LastName.value=="Last Name*"){
		errmsg += "Your last name\n";
		thisClass = document.getElementById('LastName').className;
		document.getElementById('LastName').className = thisClass + " error";
	}


	if (myForm.Email.value=="" || myForm.Email.value=="Email*"){
		errmsg += "Your email address\n";
		thisClass = document.getElementById('Email').className;
		document.getElementById('Email').className = thisClass + " error";
	} else {
		if (myForm.Email.value.indexOf('@',0)==-1 ||
			myForm.Email.value.indexOf('@',0)== 0 ||
			myForm.Email.value.indexOf('.',0)==-1) {
			errmsg += "A valid email address\n";
			thisClass = document.getElementById('Email').className;
			document.getElementById('Email').className = thisClass + " error";
		}
	}
	
	
	//Check to see if we added anything to the default error message
	if (errmsg != "The following fields are required:\n\n"){
		alert(errmsg);
		return false;
	}
	
	return true;
	
}



///////////////////////////////////////////
// Web & Design Term Glossary 
// Show/Hide various glossary terms
///////////////////////////////////////////
function showGlossary(theLetter) {
	// loop over alphabet and hide them glossary terms
	for(i=1; i<=26; i++) {
		navItem = 'glossaryNav_' + String.fromCharCode(64+i);
		document.getElementById(navItem).className = "";
		
		hideItem = 'glossary_' + String.fromCharCode(64+i);
		document.getElementById(hideItem).className = "hide";
	}
	
	// display correct glossary item(s)
	navItem = 'glossaryNav_' + theLetter;
	document.getElementById(navItem).className = "active";
	
	showItem = 'glossary_' + theLetter;
	document.getElementById(showItem).className = "show";
	
	return false;
}