/*----- Check if a string is only whitespace -----*/

function isBlankString(s){
	for (var i = 0; i < s.length; i++){
		var c = s.charAt(i);
		if ((c!= ' ') && (c != '\n') && (c != '\t') && (c != '\r')) return false;
	}
	return true;

}

/*----- Check to see if a text area or input field is empty -----*/

function isEmpty(theField) {
        if (
		  (theField.value == "")
		||(theField.value == null)
		||(isBlankString(theField.value))
	   ) 
		{ return true;} 
	else 
		{ return false; }
} 

/*----- Check to see if a radio group is empty -----*/

function isRadioEmpty(theField) {
	for (var i=0;i<theField.length;i++){
		if (theField[i].checked) {return false}
	}
	return true;		
}

/*----- Check fields in a form ---*/


function RegistrationCheck(thisForm) {

        var Empty=false; 
        var errstring="";
		
        if (isEmpty(thisForm.elements.first)&&isEmpty(thisForm.elements.last)) {
                errstring += "\n first or name"; 
                Empty=true; 
        }
        if (isEmpty(thisForm.elements.email)) {
                errstring += "\n email"; 
                Empty=true; 
        }
        if (isEmpty(thisForm.elements.phone)) {
                errstring += "\n phone number"; 
                Empty=true; 
        }
        if (isEmpty(thisForm.elements.dept)) {
                errstring += "\n department"; 
                Empty=true; 
        }
        if (isEmpty(thisForm.elements.association)) {
                errstring += "\n university association"; 
                Empty=true; 
        }

       if (thisForm.elements.workshop7.checked
        		 && 
        	thisForm.elements.workshop8.checked) 
        {
                errstring += "\n\nSelect no more than one"; 
                errstring += "\n     WebCT Vista - Creating a Course from Scratch"; 
                errstring += "\nworkshop"; 
                Empty=true; 
        }
        
       if (thisForm.elements.workshop12.checked
        		 && 
        	thisForm.elements.workshop13.checked) 
        {
                errstring += "\n\nSelect no more than one"; 
                errstring += "\n     Video Editing workshop"; 
                Empty=true; 
        }
        
        if (Empty){
			var finalerrstring=""; 
			if (Empty) finalerrstring+="The following information is required:\n\n"+errstring+"\n\n";
            alert(finalerrstring); 
            return false; 
        } else { return true; } 
}


function gradeUploadCheck(thisForm) {

        var Empty=false; 
        var errstring="";

        if (isEmpty(thisForm.elements.last_name)) {
                errstring += "\n Last Name"; 
                Empty=true; 
        }
        if (isEmpty(thisForm.elements.email)) {
                errstring += "\n Email"; 
                Empty=true; 
        }
        if (isEmpty(thisForm.elements.subject)) {
                errstring += "\n Subject"; 
                Empty=true; 
        }

        if (Empty){
			var finalerrstring=""; 
			if (Empty) finalerrstring+="The following information is required:\n\n"+errstring+"\n\n";
            alert(finalerrstring); 
            return false; 
        } else { return true; } 
}