using Novelly.Api.Chapters;
using Novelly.Api.Common;
using Novelly.Api.Common.Validation;
using Novelly.Api.Projects;

namespace Novelly.Api.Tests;

/// <summary>
/// Covers the exception-handling rework: a missing entity is an ordinary result, not a
/// thrown exception; <see cref="Guard"/> rejects missing required arguments; and a
/// service re-validates a request even when a direct caller skips the API's own filter.
/// </summary>
[TestFixture]
public class ExceptionHandlingTests : ServiceTestFixture
{
    [Test]
    public void Guard_rejects_an_empty_guid_passed_as_a_required_id() =>
        Assert.That(() => Projects.GetAsync(Guid.Empty), Throws.TypeOf<ArgumentException>());

    [Test]
    public void Guard_rejects_a_null_request_object() =>
        Assert.That(
            () => Projects.CreateAsync(null!),
            Throws.TypeOf<ArgumentNullException>());

    [Test]
    public async Task Deleting_a_missing_project_returns_false_rather_than_throwing() =>
        Assert.That(await Projects.DeleteAsync(Guid.NewGuid()), Is.False);

    [Test]
    public void A_blank_title_fails_the_create_project_validator()
    {
        var result = new CreateProjectRequestValidator().Validate(new CreateProjectRequest(""));

        Assert.Multiple(() =>
        {
            Assert.That(result.IsInvalid, Is.True);
            Assert.That(result.Errors.Select(e => e.PropertyName), Has.Member("Title"));
        });
    }

    [Test]
    public void Calling_a_service_directly_with_an_invalid_request_throws_rather_than_silently_accepting_it() =>
        Assert.That(
            () => Projects.CreateAsync(new CreateProjectRequest("")),
            Throws.TypeOf<ArgumentException>());

    [Test]
    public async Task Creating_a_chapter_under_a_missing_project_returns_null_rather_than_throwing() =>
        Assert.That(await Chapters.CreateAsync(Guid.NewGuid(), new CreateChapterRequest("Landfall")), Is.Null);
}