candreoliveira/ngMask

(function() {
  'use strict';
  angular.module('ngMask')
    .factory('OptionalService', [function() {
      function getOptionalsIndexes(mask) {
        var indexes = [];

        try {
          var regexp = /\?/g;
          var match = [];

          while ((match = regexp.exec(mask)) != null) {
            // Save the optional char
            indexes.push((match.index - 1));
          }
        } catch (e) {
          throw e;
        }

        return {
          fromMask: function() {
            return indexes;
          },
          fromMaskWithoutOptionals: function() {
            return getOptionalsRelativeMaskWithoutOptionals(indexes);
          }
        };
      }

      function getOptionalsRelativeMaskWithoutOptionals(optionals) {
        var indexes = [];
        for (var i=0; i<optionals.length; i++) {
          indexes.push(optionals[i]-i);
        }
        return indexes;
      }

      function removeOptionals(mask) {
        var newMask;

        try {
          newMask = mask.replace(/\?/g, '');
        } catch (e) {
          throw e;
        }

        return newMask;
      }

      return {
        removeOptionals: removeOptionals,
        getOptionals: getOptionalsIndexes
      }
    }]);
})();