(function () {

    "use strict";

    angular.module("EnrApp")
           .filter("lastUpdatedTimestamp", ['$filter', function ($filter) {
               return function (input) {

                   // Early Out: No data has been bound yet.
                   if (input === undefined || input === null)
                       return input;

                   // Validation: Input is not in the format date_time.
                   var indexOfUnderscore = input.indexOf("_");
                   var invalidOverallInputFormat = indexOfUnderscore === -1 || indexOfUnderscore === 0 || indexOfUnderscore === input.length - 1;
                   if (invalidOverallInputFormat)
                       return "Invalid Timestamp Format";

                   // Get raw date/time
                   var splitInput = input.split("_");
                   var datePart = splitInput[0];
                   var timePart = splitInput[1];

                   // Validation: Date and time are in correct format.
                   if (datePart.length !== 8)
                       datePart = "Invalid Date Format";
                   if (timePart.length !== 6)
                       timePart = "Invalid Time Format";

                   // Create ISO 8601 (angular usable) date from the constiuent parts
                   // insert dashes into date
                   datePart = [datePart.slice(0, 6), "-", datePart.slice(6)].join('');
                   datePart = [datePart.slice(0, 4), "-", datePart.slice(4)].join('');
                    // Add colons to the time
                   timePart = [timePart.slice(0, 4), ":", timePart.slice(4)].join('');
                   timePart = [timePart.slice(0, 2), ":", timePart.slice(2)].join('');
                   var datetime = datePart + "T" + timePart;

                   // Create human readable datetime
                   datetime = $filter("date")(datetime, 'medium');

                   return datetime;

               };
           }]);
}());