using Acl.Application;

namespace Acl.Tests;

public class AclServiceTests
{
    private sealed class FakeGateway : IZaakGateway
    {
        public ZaakRequest? Captured;
        public Uri Result { get; } = new("http://openzaak/zaken/api/v1/zaken/abc");

        public (Uri Zaak, Uri Zaaktype, DateOnly Datum)? Approved;

        public Task<Uri> OpenZaakAsync(ZaakRequest request, CancellationToken ct = default)
        {
            Captured = request;
            return Task.FromResult(Result);
        }

        public Task SetZaakToEindstatusAsync(Uri zaakUrl, Uri zaaktypeUrl, DateOnly datumStatusGezet, CancellationToken ct = default)
        {
            Approved = (zaakUrl, zaaktypeUrl, datumStatusGezet);
            return Task.CompletedTask;
        }

        public Uri? ReadReferenceFor;

        public Task<string> GetZaakIdentificatieAsync(Uri zaakUrl, CancellationToken ct = default)
        {
            ReadReferenceFor = zaakUrl;
            return Task.FromResult("REG-FROM-ZAAK");
        }
    }

    private static AclDefaults Defaults() => new()
    {
        Bronorganisatie = "517439943",
        VerantwoordelijkeOrganisatie = "517439943",
        Vertrouwelijkheidaanduiding = "openbaar",
        ZaaktypeUrl = new("http://openzaak/catalogi/api/v1/zaaktypen/big"),
    };

    private sealed class FixedClock(DateOnly today) : IClock
    {
        public DateOnly Today { get; } = today;
    }

    [Fact]
    public async Task Opening_a_zaak_default_fills_zgw_fields_and_returns_the_zaak_url()
    {
        var gateway = new FakeGateway();
        var defaults = new AclDefaults
        {
            Bronorganisatie = "517439943",
            VerantwoordelijkeOrganisatie = "517439943",
            Vertrouwelijkheidaanduiding = "openbaar",
            ZaaktypeUrl = new("http://openzaak/catalogi/api/v1/zaaktypen/big"),
        };
        var service = new AclService(gateway, defaults, new FixedClock(new DateOnly(2026, 6, 4)));

        var url = await service.OpenZaakAsync(new DomainRegistration("123456782", "reg-77"));

        Assert.Equal(gateway.Result, url);
        var req = Assert.IsType<ZaakRequest>(gateway.Captured);
        Assert.Equal("517439943", req.Bronorganisatie);
        Assert.Equal("517439943", req.VerantwoordelijkeOrganisatie);
        Assert.Equal("openbaar", req.Vertrouwelijkheidaanduiding);
        Assert.Equal(defaults.ZaaktypeUrl, req.Zaaktype);
        Assert.Equal(new DateOnly(2026, 6, 4), req.Startdatum);
        // The registration reference becomes the zaak identificatie (#78).
        Assert.Equal("reg-77", req.Identificatie);
    }

    [Fact]
    public async Task Rejects_a_null_registration_without_calling_the_gateway()
    {
        var gateway = new FakeGateway();
        var defaults = new AclDefaults
        {
            Bronorganisatie = "517439943",
            VerantwoordelijkeOrganisatie = "517439943",
            Vertrouwelijkheidaanduiding = "openbaar",
            ZaaktypeUrl = new("http://openzaak/catalogi/api/v1/zaaktypen/big"),
        };
        var service = new AclService(gateway, defaults, new FixedClock(new DateOnly(2026, 6, 4)));

        await Assert.ThrowsAsync<ArgumentNullException>(() => service.OpenZaakAsync(null!));
        Assert.Null(gateway.Captured);
    }

    [Fact]
    public async Task Approving_a_zaak_sets_it_to_its_zaaktypes_eindstatus_dated_today()
    {
        var gateway = new FakeGateway();
        var defaults = Defaults();
        var service = new AclService(gateway, defaults, new FixedClock(new DateOnly(2026, 6, 4)));
        var zaak = new Uri("http://openzaak/zaken/api/v1/zaken/abc");

        await service.ApproveZaakAsync(zaak);

        Assert.NotNull(gateway.Approved);
        Assert.Equal(zaak, gateway.Approved!.Value.Zaak);
        Assert.Equal(defaults.ZaaktypeUrl, gateway.Approved.Value.Zaaktype);
        Assert.Equal(new DateOnly(2026, 6, 4), gateway.Approved.Value.Datum);
    }

    [Fact]
    public async Task Approving_a_null_zaak_is_rejected_without_touching_the_gateway()
    {
        var gateway = new FakeGateway();
        var service = new AclService(gateway, Defaults(), new FixedClock(new DateOnly(2026, 6, 4)));

        await Assert.ThrowsAsync<ArgumentNullException>(() => service.ApproveZaakAsync(null!));
        Assert.Null(gateway.Approved);
    }

    [Fact]
    public async Task Reading_a_zaak_reference_returns_the_zaaks_identificatie()
    {
        var gateway = new FakeGateway();
        var service = new AclService(gateway, Defaults(), new FixedClock(new DateOnly(2026, 6, 4)));
        var zaak = new Uri("http://openzaak/zaken/api/v1/zaken/abc");

        var reference = await service.GetZaakReferenceAsync(zaak);

        Assert.Equal("REG-FROM-ZAAK", reference);
        Assert.Equal(zaak, gateway.ReadReferenceFor);
    }

    [Fact]
    public async Task Reading_a_null_zaak_reference_is_rejected()
    {
        var gateway = new FakeGateway();
        var service = new AclService(gateway, Defaults(), new FixedClock(new DateOnly(2026, 6, 4)));

        await Assert.ThrowsAsync<ArgumentNullException>(() => service.GetZaakReferenceAsync(null!));
        Assert.Null(gateway.ReadReferenceFor);
    }
}