using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Core.Abstractions;

namespace ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Tests.Series;

/// <summary>
///     Issue #272, plan PR F5-a — series-level (would-be integration) coverage of
///     <c>Production/LastCycleSeconds</c> + <c>Production/LastCycleStartUtc</c>.
///     The derivation is pure (no new wire calls — see
///     <c>docs/v2/focas-deployment.md</c> § "Derived telemetry") so the
///     real-simulator test asserts the existing <c>cnc_rdparam(6711)</c> +
///     cycle-timer poll that F1-b already emits drives both fields end-to-end.
/// </summary>
/// <remarks>
///     Build-only today: focas-mock has not yet shipped (tracked under
///     <c>docs/v2/implementation/focas-simulator-plan.md</c> § "Cycle-time per
///     part / last cycle delta — F5-a"). The unit-test coverage in
///     <see cref="FocasCycleDeltaTests"/> exercises every same-process invariant
///     of the derivation. The gated test below materialises the
///     <c>SimulateCycleCompletionAsync</c> + admin-endpoint contract once the
///     simulator binary lands.
/// </remarks>
[Trait("Category", "Series")]
public sealed class CycleDeltaTests
{
    [Fact]
    public void Derivation_contract_is_documented()
    {
        // Build-only scaffold — see FocasCycleDeltaTests for the actual fake-backed
        // assertion. The integration version of this test (gated on a focas-mock
        // simulator with a SimulateCycleCompletionAsync admin endpoint) will:
        //   1. Spin up FocasDriver pointed at the simulator with parts=5, timer=10s.
        //   2. Wait for the first probe tick (baseline established).
        //   3. Call simulator.SimulateCycleCompletionAsync(profile, parts: 6, timer: 18s).
        //   4. Wait for the next probe tick to refresh the production cache.
        //   5. Read Production/LastCycleSeconds + Production/LastCycleStartUtc through
        //      the OPC UA surface; assert delta == 8.0 and the timestamp is now - 8s.
        // The driver-side derivation already locks the contract in unit tests; this
        // scaffold pins the simulator-side contract for the focas-mock implementor.
        var info = typeof(FocasDriver).GetMethod(
            nameof(FocasDriver.UpdateCycleDerivation),
            System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Static);
        info.ShouldNotBeNull();
    }

    [Fact(Skip = "Hardware-gated — requires focas-mock with the SimulateCycleCompletionAsync admin endpoint (focas-simulator-plan.md § 'Cycle-time per part / last cycle delta — F5-a').")]
    public Task Live_simulator_cycle_completion_round_trip()
    {
        // Body deliberately empty — the [Skip] attribute keeps this off the CI
        // lane. When focas-mock lands the SimulateCycleCompletionAsync helper +
        // matching admin endpoint, this test materialises a FocasDriver pointed
        // at the simulator + drives the parts-count 5 -> 6 transition through real
        // wire calls.
        return Task.CompletedTask;
    }
}