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// Moq mocking + WebApplicationFactory integration test

using Moq;
using Xunit;
using Microsoft.AspNetCore.Mvc.Testing;

// ------- Unit test with Moq -------
public interface IOrderRepository
{
    Order? GetById(int id);
    void   Save(Order order);
}

public class OrderService
{
    private readonly IOrderRepository _repo;
    public OrderService(IOrderRepository repo) => _repo = repo;

public string GetOrderStatus(int id)
    {
        var order = _repo.GetById(id);
        return order is null ? "Not Found" : order.Status;
    }
}

public record Order(int Id, string Status);

public class OrderServiceTests
{
    [Fact]
    public void GetOrderStatus_ExistingOrder_ReturnsStatus()
    {
        // Arrange
        var mockRepo = new Mock<IOrderRepository>();
        mockRepo.Setup(r => r.GetById(1))
                .Returns(new Order(1, "Shipped"));

var service = new OrderService(mockRepo.Object);

// Act
        string status = service.GetOrderStatus(1);

// Assert
        Assert.Equal("Shipped", status);
        mockRepo.Verify(r => r.GetById(1), Times.Once);
    }

[Fact]
    public void GetOrderStatus_MissingOrder_ReturnsNotFound()
    {
        var mockRepo = new Mock<IOrderRepository>();
        mockRepo.Setup(r => r.GetById(It.IsAny<int>())).Returns((Order?)null);

var service = new OrderService(mockRepo.Object);
        Assert.Equal("Not Found", service.GetOrderStatus(99));
    }
}

// ------- Integration test with WebApplicationFactory -------
public class ProductApiTests : IClassFixture<WebApplicationFactory<Program>>
{
    private readonly HttpClient _client;
    public ProductApiTests(WebApplicationFactory<Program> factory)
        => _client = factory.CreateClient();

[Fact]
    public async Task GetProducts_ReturnsOkWithList()
    {
        var response = await _client.GetAsync("/api/products");
        response.EnsureSuccessStatusCode();
        string body = await response.Content.ReadAsStringAsync();
        Assert.Contains("Laptop", body);
    }
}