// This library is used for form validaton
function FormValidation(form) {
	// public variables
    var result = {}
	result.validated 	= false;
	result.error		= '';
	
	function hasRequiredValues(requiredValues) {
		var emptyValues		= [];
		
		for (var i in requiredValues) {
			var requiredValue = requiredValues[i];
			if (form[requiredValue].value == "") {
				// form empty, add to the list
				emptyValues.push(requiredValue);
			} else {
				// remove any classes if available
				$("#" + requiredValue).removeClass("warning");
			}
		}

		if (emptyValues.length > 0) { // there are empty values 
			// first generate the error string
			for (var i in emptyValues) {				
				// Get the correct name for this field from the <label> assigned to it
				result.error += $("label[for=" + emptyValues[i] + "]").text() + ", ";
				
				// also light up the specific fields
				$("#" + emptyValues[i]).addClass("warning");
			} 
			// we cut off the last 2 characters from the string to prevent the ', ' at the end of the string
			result.error = messages.EMPTY_VALUE + result.error.substr(0, (result.error.length - 2));
			return false;
		} else {
			// no empty values, so this form has all the required values
			return true;
		}
	}
	
	function hasValidEmail() {
		var emailRegEx =/^[\w][\w\.\-]*@(?:[a-zA-Z0-9\-]+\.)+[a-zA-Z]{2,4}$/
		
		if (form.email.value.search(emailRegEx) == -1) {
			// email not valid, change the error message
			result.error = messages.INVALID_EMAIL;
			$("#email").addClass("warning");
			return false;
		} else {
			$("#email").removeClass("warning");
			return true;
		}
	}
	
	function hasGoodEmailProvider(providers) {
		// searches the email string for any occurences of unwanted e-mail providers (e.g. hotmail, yahoo, gmail)
		for (var i in providers) {
			var provider = providers[i];
			if (form.email.value.toLowerCase().indexOf(provider) != -1) {
				// bad email provider
				result.error = messages.INVALID_EMAIL_PROVIDER + provider;
				$("#email").addClass("warning");
				return false;
			}
		}
		$("#email").removeClass("warning");		
		return true;
	}
	
	function hasCheckedDisclaimer() {
		if (form. disclaimerAgree.checked) {
			$("#disclaimerAgreeBox").removeClass("warning");
			return true;
		} else {
			result.error = messages.DISCLAIMER_NOT_AGREED;
			$("#disclaimerAgreeBox").addClass("warning");			
			return false;
		}
	}
	
	function hasValidFiletype(filetypes) {
		for (var i in filetypes) {
			var filetype = filetypes[i];
			if (form.file.value.toLowerCase().indexOf(filetype) != -1) {
				$("#file").removeClass("warning");
				return true;
			} 
		}
		
		// no valid filetypes found
		result.error = messages.INVALID_FILETYPE;
		$("#file").addClass("warning");
		return false;
	}		
	
	// The whole routine
	if (hasRequiredValues(["file", "title", "source", "name", "email"]) == false) return result;
	if (hasValidEmail() == false) return result;
	if (hasGoodEmailProvider(['hotmail.com', 'gmail.com', 'yahoo.com', 'live.com', 'live.nl', 'yahoo.ca', 'msn.com']) == false) return result;
	if (hasCheckedDisclaimer() == false) return result;
	if (hasValidFiletype(['.png', '.jpg', '.jpeg', '.gif']) == false) return result;
	
	// all checks passed, upload the photograph
	result.validated = true;
	return result; 
}