lmxopcua/tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.OpcUaClient.Tests/OpcUaClientReconnectTests.cs

using Shouldly;
using Xunit;

namespace ZB.MOM.WW.OtOpcUa.Driver.OpcUaClient.Tests;

/// <summary>
///     Scaffold tests for <see cref="SessionReconnectHandler"/> wiring. Wire-level
///     disconnect-reconnect-resume coverage against a live upstream server lands with the
///     in-process fixture — too much machinery for a unit-test-only lane.
/// </summary>
[Trait("Category", "Unit")]
public sealed class OpcUaClientReconnectTests
{
    /// <summary>Verifies that the default reconnect period matches the driver specification of 5 seconds.</summary>
    [Fact]
    public void Default_ReconnectPeriod_matches_driver_specs_5_seconds()
    {
        new OpcUaClientDriverOptions().ReconnectPeriod.ShouldBe(TimeSpan.FromSeconds(5));
    }

    /// <summary>Verifies that reconnect period can be configured for aggressive or relaxed retries.</summary>
    [Fact]
    public void Options_ReconnectPeriod_is_configurable_for_aggressive_or_relaxed_retry()
    {
        var opts = new OpcUaClientDriverOptions { ReconnectPeriod = TimeSpan.FromMilliseconds(500) };
        opts.ReconnectPeriod.ShouldBe(TimeSpan.FromMilliseconds(500));
    }

    /// <summary>Verifies that the driver starts with no reconnect handler active before initialization.</summary>
    [Fact]
    public void Driver_starts_with_no_reconnect_handler_active_pre_init()
    {
        // The reconnect handler is lazy — spun up only when a bad keep-alive fires. Pre-init
        // there's no session to reconnect, so the field must be null (indirectly verified by
        // the lifecycle-shape test suite catching any accidental construction).
        using var drv = new OpcUaClientDriver(new OpcUaClientDriverOptions(), "opcua-reconnect");
        drv.GetHealth().State.ShouldBe(Core.Abstractions.DriverState.Unknown);
    }
}