using FakeItEasy;

using System;

using System.Collections.Generic;

using System.Web;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        new UnitTests().PerformUnitTest();

    }

}

​

// INSTRUCTIONS:

​

// The CustomerValidator class retrieves a value from the current HttpContext,

// uses that value to pull a record from the database, plus makes an API call.

​

// Refactor CustomerValidator so that the PerformUnitTest() method can execute 

// without interacting with any of these external services.  GetCustomerAndValidateZip()

// must still interact with all these services when run in the context of the

// host application.

​

// Adjust the unit test so that it tests one good zip code and one bad one,

// resulting in two "PASS" lines in the console.

​

// Focus on what needs to change in CustomerValidator() and UnitTests():

// changes to the other classes would be expected in real life, but are not

// necessary for this activity.

public class UnitTests

{

    private CustomerValidator _customerValidator;

    private Customer _validCustomer;

    private Customer _invalidCustomer;

    public void PerformUnitTest()

    {

        SetUp();

        CustomerValidator_ValidCustomerZipCode_ReturnsTrue();

        CustomerValidator_InvalidCustomerZipCode_ReturnsFalse();

    }

    private void SetUp()

    {

        _validCustomer = new Customer()

        {

            ID = 1,

            ZipCode = "12345"

        };

        _invalidCustomer = new Customer()

        {

            ID = 2,

            ZipCode = "54321"

        };

        var customerRepository = A.Fake<ICustomerRepository>();

        A.CallTo(() => customerRepository.GetCustomer(_validCustomer.ID)).Returns(_validCustomer);

        A.CallTo(() => customerRepository.GetCustomer(_invalidCustomer.ID)).Returns(_invalidCustomer);

        var httpClient = A.Fake<IHttpClient>();

        A.CallTo(() => httpClient.Get<List<string>>(A<string>.Ignored)).Returns(

            new List<string>() { _validCustomer.ZipCode });

        _customerValidator = new CustomerValidator(customerRepository, httpClient);

    }

    private void CustomerValidator_ValidCustomerZipCode_ReturnsTrue()

    {

        // Arrange

        HttpContext.Current.Profile.SetPropertyValue("CustomerId", _validCustomer.ID);

        // Act

        var output = _customerValidator.GetCustomerAndValidateZip();

        // Assert

        PrintResult(true, output);

    }

    private void CustomerValidator_InvalidCustomerZipCode_ReturnsFalse()

    {

        // Arrange

        HttpContext.Current.Profile.SetPropertyValue("CustomerId", _invalidCustomer.ID);

        // Act

        var output = _customerValidator.GetCustomerAndValidateZip();

        // Assert

        PrintResult(false, output);

    }

    private void PrintResult(bool expected, bool actual)

    {

        var result = expected == actual ? "PASS" : "FAIL";

        Console.WriteLine(result);

    }

}

​

public class CustomerValidator

{

    private readonly ICustomerRepository _customerRepository;

    private readonly IHttpClient _httpClient;

    public CustomerValidator(ICustomerRepository customerRepository, IHttpClient httpClient)

    {

        _customerRepository = customerRepository;

        _httpClient = httpClient;

    }

    public bool GetCustomerAndValidateZip()

    {

        int customerId = (int)HttpContext.Current.Profile.GetPropertyValue("CustomerId");

        var customer = _customerRepository.GetCustomer(customerId);

        var allZipCodes = GetAllValidZipCodes();

        return allZipCodes.Contains(customer.ZipCode);

    }

    private List<string> GetAllValidZipCodes()

    {

        return _httpClient.Get<List<string>>("http://fakeapi.forzipcodes.com/GetAll");

    }

}

​

public class Customer

{

    public int ID { get; set; }

    public string ZipCode { get; set; }

}

​

public interface ICustomerRepository

{

    Customer GetCustomer(int customerId);

}

​

public class CustomerRepository : ICustomerRepository

{

    public Customer GetCustomer(int customerId)

    {

        var db = new DbContext();

        return db.Customers.SingleOrDefault(i => i.ID == customerId);

    }

}

​

public class DbContext

{

    public List<Customer> Customers { get; set; }

}

​

public interface IHttpClient

{

    T Get<T>(string url);

}

​

public class HttpClient : IHttpClient

{

    public T Get<T>(string url)

    {

        // perform HTTP call and return response

        return default(T);

    }

}