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

namespace ZB.MOM.WW.OtOpcUa.Driver.S7.IntegrationTests.S7_1500;

/// <summary>
///     PR-S7-C5 — integration coverage for the post-<c>OpenAsync</c> pre-flight
///     PUT/GET enablement probe. Snap7 always allows reads (no PUT/GET gating
///     in the simulator), so the integration scope is limited to the happy
///     path: pre-flight succeeds against the seeded MW0/DBW0 fingerprint and
///     the driver reaches <see cref="DriverState.Healthy"/>. The "PUT/GET
///     disabled" failure path is unit-tested via
///     <c>S7PreflightClassifier</c> and documented as a follow-up live-firmware
///     test in <c>docs/drivers/S7-Test-Fixture.md</c>.
/// </summary>
[Collection(Snap7ServerCollection.Name)]
[Trait("Category", "Integration")]
[Trait("Device", "S7_1500")]
public sealed class S7_1500PreflightTests(Snap7ServerFixture sim)
{
    [Fact]
    public async Task Driver_preflight_passes_when_probe_address_seeded()
    {
        if (sim.SkipReason is not null) Assert.Skip(sim.SkipReason);

        // Use the standard S7-1500 profile — DB1.DBW0 / DB1.DBW10 / etc are seeded
        // by the snap7 profile so the default MW0 probe (or DB1.DBW0 fallback)
        // exists at read time.
        var options = S7_1500Profile.BuildOptions(sim.Host, sim.Port);
        // Override the probe loop knob set by S7_1500Profile: the loop stays
        // disabled, but Probe.ProbeAddress + SkipPreflight are what RunPreflightAsync
        // consults. ProbeAddress defaults to MW0 which python-snap7 zeros at startup;
        // any successful read (zeros included) satisfies the pre-flight.
        var preflightOptions = new S7DriverOptions
        {
            Host = options.Host,
            Port = options.Port,
            CpuType = options.CpuType,
            Rack = options.Rack,
            Slot = options.Slot,
            Timeout = options.Timeout,
            Tags = options.Tags,
            // ProbeAddress = "MW0" (default); SkipPreflight = false (default).
            // Background probe loop disabled to avoid mailbox contention with the test.
            Probe = new S7ProbeOptions { Enabled = false },
        };

        await using var drv = new S7Driver(preflightOptions, driverInstanceId: "s7-preflight-pass");
        await drv.InitializeAsync("{}", TestContext.Current.CancellationToken);

        // If pre-flight tripped the typed exception, InitializeAsync would have thrown
        // before reaching this line. Healthy state proves the probe succeeded.
        drv.GetHealth().State.ShouldBe(DriverState.Healthy,
            "pre-flight probe must succeed against the seeded snap7 fingerprint");
    }

    [Fact]
    public async Task Driver_preflight_skipped_when_SkipPreflight_set()
    {
        if (sim.SkipReason is not null) Assert.Skip(sim.SkipReason);

        // Skipping the pre-flight is opt-in. The driver must still reach Healthy state
        // because the connect path itself succeeds; the only thing different is that no
        // probe read fires before _health flips.
        var options = S7_1500Profile.BuildOptions(sim.Host, sim.Port);
        var skipOptions = new S7DriverOptions
        {
            Host = options.Host,
            Port = options.Port,
            CpuType = options.CpuType,
            Rack = options.Rack,
            Slot = options.Slot,
            Timeout = options.Timeout,
            Tags = options.Tags,
            Probe = new S7ProbeOptions { Enabled = false, SkipPreflight = true },
        };

        await using var drv = new S7Driver(skipOptions, driverInstanceId: "s7-preflight-skipped");
        await drv.InitializeAsync("{}", TestContext.Current.CancellationToken);

        drv.GetHealth().State.ShouldBe(DriverState.Healthy);
    }
}