// JavaScript Document 
//validate the link submission page

function validateLink(){
	//form has been submitted, hide the success or unsuccess error messages
	if(document.getElementById('successError')){
		document.getElementById('successError').style.display = "none";
	}

	var emailField, titleField, addyField, txtField;
	var pattern = /[0-9]/;  //regular expression looking for a digit between 0 and 9
	var emailPattern = /\w+@\w+\.\w{1,3}/;
	var urlPattern = /^http/;
	var errors = new Array();	
	var allow;
	
	
	emailField = document.getElementById('email');
	titleField = document.getElementById('title');
	addyField = document.getElementById('addy');
	txtField = document.getElementById('txt');
	
	if(emailField.value == ''){
		document.getElementById('emailError').style.display = "block";
		errors[0] = 'yes';
	}else{
		//the field is not empty so time to compare it against the email reg expression
		if(!emailPattern.test(emailField.value)){
			errors[0] = 'yes';
			document.getElementById('emailError').style.display = "block";
		}else{
			document.getElementById('emailError').style.display = "none";
			errors[0] = '';
		}
	}
	
	if(titleField.value == ''){
		document.getElementById('titleError').style.display = "block";
		errors[1] = 'yes';
	}else{
		document.getElementById('titleError').style.display = "none";
		errors[1] = '';
	}
	
	if(addyField.value == ''){
		document.getElementById('addyError').style.display = "block";
		errors[2] = 'yes';
	}else{
		if(!urlPattern.test(addyField.value)){
			document.getElementById('addyError').style.display = "block";
			errors[2] = 'yes';
		}else{
			document.getElementById('addyError').style.display = "none";
			errors[2] = '';
		}
	}
	
	if(txtField.value == ''){
		document.getElementById('txtError').style.display = "block";
		errors[3] = 'yes';
	}else{
		document.getElementById('txtError').style.display = "none";
		errors[3] = '';
	}
	
	for(i=0; i<errors.length; i++){
		if(errors[i] == 'yes'){
			allow = 'no';
		}
	}
	
	if(allow == 'no'){
		return false;

	}else{
		return true;
	}

}