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

namespace ZB.MOM.WW.OtOpcUa.Driver.AbCip.IntegrationTests.Emulate;

/// <summary>
///     Golden-box-tier UDT read tests against Rockwell Studio 5000 Logix Emulate.
///     Promotes the whole-UDT-read optimization (task #194) from unit-only coverage
///     (golden Template Object byte buffers + <see cref="AbCipUdtMemberLayoutTests"/>)
///     to end-to-end wire-level coverage — Emulate's firmware speaks the same CIP
///     Template Object responses real hardware does, so the member-offset math + the
///     <c>AbCipUdtReadPlanner</c> grouping get validated against production semantics.
/// </summary>
/// <remarks>
///     <para><b>Required Emulate project state</b> (see <c>LogixProject/README.md</c>
///     for the L5X export that seeds this; ship the project once Emulate is on the
///     integration host):</para>
///     <list type="bullet">
///       <item>UDT <c>Motor_UDT</c> with members <c>Speed : DINT</c>, <c>Torque : REAL</c>,
///         <c>Status : DINT</c> — the member set <see cref="AbCipUdtMemberLayoutTests"/>
///         uses as its declared-layout golden reference.</item>
///       <item>Controller-scope tag <c>Motor1 : Motor_UDT</c> with seed values
///         Speed=<c>1800</c>, Torque=<c>42.5f</c>, Status=<c>0x0001</c>.</item>
///     </list>
///     <para>Runs only when <c>AB_SERVER_PROFILE=emulate</c>. With ab_server
///     (the default), skips cleanly — ab_server lacks UDT / Template Object emulation
///     so this wire-level test couldn't pass against it regardless.</para>
/// </remarks>
[Collection("AbServerEmulate")]
[Trait("Category", "Integration")]
[Trait("Tier", "Emulate")]
public sealed class AbCipEmulateUdtReadTests
{
    [AbServerFact]
    public async Task WholeUdt_read_decodes_each_member_at_its_Template_Object_offset()
    {
        AbServerProfileGate.SkipUnless(AbServerProfileGate.Emulate);

        var endpoint = Environment.GetEnvironmentVariable("AB_SERVER_ENDPOINT")
            ?? throw new InvalidOperationException(
                "AB_SERVER_ENDPOINT must be set to the Logix Emulate instance " +
                "(e.g. '10.0.0.42:44818') when AB_SERVER_PROFILE=emulate.");

        var options = new AbCipDriverOptions
        {
            Devices = [new AbCipDeviceOptions($"ab://{endpoint}/1,0")],
            Tags = [
                new AbCipTagDefinition(
                    Name: "Motor1",
                    DeviceHostAddress: $"ab://{endpoint}/1,0",
                    TagPath: "Motor1",
                    DataType: AbCipDataType.Structure,
                    Members: [
                        new AbCipStructureMember("Speed",  AbCipDataType.DInt),
                        new AbCipStructureMember("Torque", AbCipDataType.Real),
                        new AbCipStructureMember("Status", AbCipDataType.DInt),
                    ]),
            ],
            Timeout = TimeSpan.FromSeconds(5),
        };

        await using var drv = new AbCipDriver(options, driverInstanceId: "emulate-udt-smoke");
        await drv.InitializeAsync("{}", TestContext.Current.CancellationToken);

        // Whole-UDT read optimization from task #194: one libplctag read on the
        // parent tag, three decodes from the buffer at member offsets. Asserts
        // Emulate's Template Object response matches what AbCipUdtMemberLayout
        // computes from the declared member set.
        var snapshots = await drv.ReadAsync(
            ["Motor1.Speed", "Motor1.Torque", "Motor1.Status"],
            TestContext.Current.CancellationToken);

        snapshots.Count.ShouldBe(3);
        foreach (var s in snapshots) s.StatusCode.ShouldBe(AbCipStatusMapper.Good);
        Convert.ToInt32(snapshots[0].Value).ShouldBe(1800);
        Convert.ToSingle(snapshots[1].Value).ShouldBe(42.5f, tolerance: 0.001f);
        Convert.ToInt32(snapshots[2].Value).ShouldBe(0x0001);
    }
}