/*
copyright shrawan kumar keshri till 2020
*/


function isValidEmail(email, required) {    if (required==undefined) {         required=true;    }
    if (email==null) {
        if (required) {         return false;       }        return true;    }    if (email.length==0) {  
        if (required) {
            return false;
        }
        return true;    }    if (! allValidChars(email)) {          return false;
    }
    if (email.indexOf("@") < 1) {         return false;
    } else if (email.lastIndexOf(".") <= email.indexOf("@")) {         return false;    } else if (email.indexOf("@") == email.length) { 
        return false;
    } else if (email.indexOf("..") >=0) { 	return false;
    } else if (email.indexOf(".") == email.length) { 	return false;
    }
    return true;}

function allValidChars(email) {
  var parsed = true;
  var validchars = "abcdefghijklmnopqrstuvwxyz0123456789@.-_";  for (var i=0; i < email.length; i++) { var letter = email.charAt(i).toLowerCase();
    if (validchars.indexOf(letter) != -1)continue; parsed = false;  break; }  return parsed;
}