using Akka.Actor;
using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Commons.Interfaces;
using ZB.MOM.WW.OtOpcUa.Commons.Messages.Fleet;
using ZB.MOM.WW.OtOpcUa.Commons.Types;
using ZB.MOM.WW.OtOpcUa.Runtime.Tests.Harness;

namespace ZB.MOM.WW.OtOpcUa.Runtime.Tests.Drivers;

/// <summary>
///     Review 02 U1: <c>GetDiagnostics</c> answered a placeholder — <c>Guid.Empty</c>, "Spawned", zero devices and
///     "now" for every child, in every behaviour — so the snapshot looked live and said nothing. It now carries
///     each child's row id, authored name, last-published health state, device counts and last change time.
/// </summary>
public sealed class DriverHostActorDiagnosticsTests : RuntimeActorTestBase
{
    private static readonly RevisionHash RevA = RevisionHash.Parse(new string('a', 64));
    private static readonly NodeId TestNode = NodeId.Parse("node-1:4053");
    private const string DriverId = "DI-1";

    [Fact]
    public async Task A_connected_child_reports_its_row_id_name_health_state_and_device_count()
    {
        var db = NewInMemoryDbFactory();
        var rowId = Guid.NewGuid();
        var before = DateTime.UtcNow.AddSeconds(-1);
        var factory = new RecordingSubscribableDriverFactory("Modbus");
        var deploymentId = V3ArtifactSeeder.SeedV3Deployment(
            db, RevA, new[] { (DriverId, "Line1-Modbus", "dev1", "speed", "Float", false) },
            Array.Empty<(string, string, string, string, string?)>(),
            enabled: true, driverRowIds: new Dictionary<string, Guid> { [DriverId] = rowId });
        var (host, _, _) = V3ArtifactSeeder.SpawnHostAndApply(this, db, TestNode, deploymentId, RevA, factory);

        var snapshot = await AwaitDiagnosticsAsync(host, s => s.Drivers.Any(d => d.State == "Healthy"));

        snapshot.NodeId.ShouldBe(TestNode);
        snapshot.CurrentRevision.ShouldBe(RevA);
        snapshot.RunningFromCache.ShouldBeFalse();
        var driver = snapshot.Drivers.ShouldHaveSingleItem();
        driver.DriverInstanceId.ShouldBe(rowId, "the real row id, not Guid.Empty");
        driver.Name.ShouldBe("Line1-Modbus", "the authored name, not the instance id");
        driver.State.ShouldBe("Healthy");
        driver.ConnectedDevices.ShouldBe(1);
        driver.FaultedDevices.ShouldBe(0);
        driver.LastChangeUtc.ShouldBeGreaterThan(before);
        driver.LastChangeUtc.ShouldBeLessThanOrEqualTo(DateTime.UtcNow);
    }

    [Fact]
    public async Task A_stubbed_child_reports_Stubbed_with_no_devices()
    {
        var db = NewInMemoryDbFactory();
        // The factory answers for a type the artifact does not use, so the host stubs the child.
        var factory = new RecordingSubscribableDriverFactory("NotModbus");
        var deploymentId = V3ArtifactSeeder.SeedV3Deployment(
            db, RevA, new[] { (DriverId, "Modbus", "dev1", "speed", "Float", false) },
            Array.Empty<(string, string, string, string, string?)>(), enabled: true);
        var (host, _, _) = V3ArtifactSeeder.SpawnHostAndApply(this, db, TestNode, deploymentId, RevA, factory);

        var snapshot = await AwaitDiagnosticsAsync(host, s => s.Drivers.Count == 1);

        var driver = snapshot.Drivers.Single();
        driver.State.ShouldBe("Stubbed");
        driver.ConnectedDevices.ShouldBe(0);
        driver.FaultedDevices.ShouldBe(0);
    }

    private async Task<NodeDiagnosticsSnapshot> AwaitDiagnosticsAsync(IActorRef host, Func<NodeDiagnosticsSnapshot, bool> ready)
    {
        NodeDiagnosticsSnapshot? snapshot = null;
        await AwaitAssertAsync(async () =>
        {
            snapshot = await host.Ask<NodeDiagnosticsSnapshot>(new GetDiagnostics(CorrelationId.NewId()), PresenceBudget);
            ready(snapshot).ShouldBeTrue();
        }, PresenceBudget);
        return snapshot!;
    }
}