(function () {
  'use strict';

  angular.module('debounce', []).factory('debounce', ['$timeout', '$q', function ($timeout, $q) {
    return function (func, wait, immediate) {
      var timeout;
      var deferred = $q.defer();
      return function () {
        var context = this, args = arguments;
        var later = function () {
          timeout = null;
          if (!immediate) {
            deferred.resolve(func.apply(context, args));
            deferred = $q.defer();
          }
        };
        var callNow = immediate && !timeout;
        if (timeout) {
          $timeout.cancel(timeout);
        }
        timeout = $timeout(later, wait);
        if (callNow) {
          deferred.resolve(func.apply(context, args));
          deferred = $q.defer();
        }
        return deferred.promise;
      };
    };
  }]);

})();