Please suggest how to write a Jasmine Test case for below angularjs code

In below example I want to mock dataService.The problem is I need to test the functionality after the data is returned under function(data).

As the logic is dependent on the data returned.I think mocking/Spying the dataservice might not help in this regard.

Kindly provide the probable solution.

var app = angular.module('app', []);
app.controller('Controller', ['$scope', '$location', 'dataService', '$window', 'OtherService', 'Config', function ($scope, $location, dataService, $window, SomeService, Config) {

$scope.btnClick = function () {
    var SomeNumber = $scope.enteredNumber;
    if (SomeNumber == "xyz") {
        $scope.errorType = 'errorRequired';
    }
    else {

        dataService.validate_enteredNumber(SomeNumber, function (data) {
                                if (data != null) {
                                  if (data.responsetype == 1) {
                                        $scope.errortype = data.responsemessage;
                                    }
                    else {
                        dataservice.getdetailsforenterednumber(data.responsemessage, function (getdata) {
                            if (getdata.responsetype == 1) {
                                $scope.errortype = getdata.responsemessage;
                            }
                            else if (getdata.responsetype == 2) {
                                if (getdata.responsemessage.touppercase() == "consumer")
                                    $window.location.href = "url";
                            }
                            else
                                $location.path('/Somelist').search({ SomeNumber: getdata.responsemessage });
                        });
                    }
                                    }



        });
    }
}


if ($location.search().SomeNumber != null) {
    $scope.enteredNumber = $location.search().SomeNumber;
    $scope.btnClick();
}

} ]);