// JavaScript Document
function changeState2(checkbox, textbox, textbox2){
  var txt = document.getElementById(textbox);
  var txt2 = document.getElementById(textbox2);
  var chk = document.getElementById(checkbox);

  if (chk.checked == false){
    txt.disabled = "disabled";
	txt.value = "";
	txt2.disabled = "disabled";
	txt2.value = "";
  }
  else if (chk.checked == true){
    txt.disabled = "";
	txt.value = "Enter your title...";
	txt2.disabled = "";
  }
}
function changeState1(checkbox, textbox){
  var txt = document.getElementById(textbox);
  var chk = document.getElementById(checkbox);

  if (chk.checked == false){
    txt.disabled = true;
  }
  else if (chk.checked == true){
    txt.disabled = false;
  }
}
function validate() {
	var filename = document.getElementById("abstract").value;
	var ext = getExt(filename);
	if(ext == "pdf" || ext == "doc" || ext == "docx"){
		document.getElementById("next2").disabled = "";
		return true;
	}
	else{
		alert("Please upload PDF, doc, and docx files only.");
		document.getElementById("next2").disabled = "disabled";
		return false;
	}
}
	
function getExt(filename) {
	var dot_pos = filename.lastIndexOf(".");
	if(dot_pos == -1)
		return "";
	return filename.substr(dot_pos+1).toLowerCase();
	}