EmployeesControllerTests.cs

namespace TalentManagementAPI.WebApi.Tests.Controllers
{
    public class EmployeesControllerTests
    {
        private readonly Mock<IMediator> _mediatorMock = new();
        private readonly EmployeesController _controller;

        public EmployeesControllerTests()
        {
            _controller = new EmployeesController();
            var services = new ServiceCollection();
            services.AddSingleton(_mediatorMock.Object);
            _controller.ControllerContext = new ControllerContext
            {
                HttpContext = new DefaultHttpContext
                {
                    RequestServices = services.BuildServiceProvider()
                }
            };
        }

        [Fact]
        public async Task Get_ShouldReturnPagedEmployees()
        {
            var query = new GetEmployeesQuery { PageNumber = 1, PageSize = 5 };
            var payload = PagedResult<IEnumerable<Entity>>.Success(new List<Entity> { new() }, 1, 5, new RecordsCount { RecordsFiltered = 1, RecordsTotal = 1 });
            _mediatorMock.Setup(m => m.Send(It.IsAny<GetEmployeesQuery>(), It.IsAny<CancellationToken>())).ReturnsAsync(payload);

            var result = await _controller.Get(query);

            var okResult = result as OkObjectResult;
            okResult.Should().NotBeNull();
            okResult!.Value.Should().Be(payload);
        }

        [Fact]
        public async Task Post_ShouldReturnCreatedResult()
        {
            var command = new CreateEmployeeCommand
            {
                FirstName = "Jane",
                LastName = "Doe",
                Email = "jane@example.com",
                EmployeeNumber = "E-100",
                PositionId = Guid.NewGuid(),
                Salary = 5000,
                Birthday = DateTime.UtcNow.AddYears(-30)
            };
            var response = Result<Guid>.Success(Guid.NewGuid());
            _mediatorMock.Setup(m => m.Send(command, It.IsAny<CancellationToken>())).ReturnsAsync(response);

            var result = await _controller.Post(command);

            var created = result as CreatedAtActionResult;
            created.Should().NotBeNull();
            created!.Value.Should().Be(response);
            _mediatorMock.Verify(m => m.Send(command, It.IsAny<CancellationToken>()), Times.Once);
        }

        [Fact]
        public async Task Delete_ShouldInvokeMediator()
        {
            var id = Guid.NewGuid();
            var response = Result<Guid>.Success(id);
            _mediatorMock.Setup(m => m.Send(It.Is<DeleteEmployeeByIdCommand>(c => c.Id == id), It.IsAny<CancellationToken>())).ReturnsAsync(response);

            var result = await _controller.Delete(id);

            var okResult = result as OkObjectResult;
            okResult.Should().NotBeNull();
            okResult!.Value.Should().Be(response);
        }

        [Fact]
        public async Task Put_WithMismatchedIds_ShouldReturnBadRequest()
        {
            var command = new UpdateEmployeeCommand { Id = Guid.NewGuid() };
            var result = await _controller.Put(Guid.NewGuid(), command);

            result.Should().BeOfType<BadRequestResult>();
        }
    }

}