using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Core.Abstractions;
using ZB.MOM.WW.OtOpcUa.Driver.S7.SymbolImport;
using S7NetCpuType = global::S7.Net.CpuType;

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

/// <summary>
///     PR-S7-D2 — UDT fan-out integration test against the python-snap7 S7-1500 fixture.
///     Seeds a 3-member UDT (Real + Int + Bool) into <c>DB1.MyUdt[400]</c> via
///     <c>Docker/profiles/s7_1500.json</c>'s <c>udt_layout</c> meta-seed, declares the
///     same layout in driver options, and verifies the fanned-out leaf reads return the
///     seeded values end-to-end through real S7comm. Build-only by default — the
///     simulator fixture skips when python-snap7 isn't running, so this test contributes
///     to the CI matrix without requiring docker locally.
/// </summary>
[Collection(Snap7ServerCollection.Name)]
[Trait("Category", "Integration")]
[Trait("Device", "S7_1500")]
public sealed class S7_1500UdtFanOutTests(Snap7ServerFixture sim)
{
    private const string ParentTagName = "MyUdt";

    /// <summary>
    ///     UDT layout matching the <c>udt_layout</c> meta-seed in the JSON profile.
    ///     Pressure (Real) at byte 0, Status (Int16) at byte 4, Enabled (Bool) at byte 6.
    /// </summary>
    private static readonly S7UdtDefinition MyUdt = new(
        Name: "MyUdt",
        Members:
        [
            new S7UdtMember("Pressure", 0, S7DataType.Float32),
            new S7UdtMember("Status", 4, S7DataType.Int16),
            new S7UdtMember("Enabled", 6, S7DataType.Bool),
        ],
        SizeBytes: 7);

    private static S7DriverOptions BuildUdtOptions(string host, int port) => new()
    {
        Host = host,
        Port = port,
        CpuType = S7NetCpuType.S71500,
        Timeout = TimeSpan.FromSeconds(5),
        Probe = new S7ProbeOptions { Enabled = false },
        Tags =
        [
            // Parent UDT tag — base address points at byte 400 in DB1, where the
            // simulator seeded the UDT contents. Fan-out emits three scalar leaves:
            //   MyUdt.Pressure  -> DB1.DBD400 (Real 12.5)
            //   MyUdt.Status    -> DB1.DBW404 (Int16 7)
            //   MyUdt.Enabled   -> DB1.DBX406.0 (Bool true)
            new S7TagDefinition(ParentTagName, "DB1.DBX400.0", S7DataType.Byte, UdtName: "MyUdt"),
        ],
        Udts = [MyUdt],
    };

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

        var options = BuildUdtOptions(sim.Host, sim.Port);
        await using var drv = new S7Driver(options, driverInstanceId: "s7-udt-fanout");
        await drv.InitializeAsync("{}", TestContext.Current.CancellationToken);

        // After fan-out the parent UDT name is gone from the tag map; only the leaves
        // are readable. Reading the parent should surface BadNodeIdUnknown.
        var parent = await drv.ReadAsync([ParentTagName], TestContext.Current.CancellationToken);
        parent[0].StatusCode.ShouldNotBe(0u, "parent UDT tag must be replaced by its leaves");

        // Read the three leaves and assert the seeded values come back.
        var leaves = await drv.ReadAsync(
            ["MyUdt.Pressure", "MyUdt.Status", "MyUdt.Enabled"],
            TestContext.Current.CancellationToken);

        leaves.Count.ShouldBe(3);
        foreach (var s in leaves)
            s.StatusCode.ShouldBe(0u, "every UDT leaf read must succeed end-to-end");

        Convert.ToSingle(leaves[0].Value).ShouldBe(12.5f, tolerance: 0.0001f);
        Convert.ToInt32(leaves[1].Value).ShouldBe(7);
        Convert.ToBoolean(leaves[2].Value).ShouldBeTrue();
    }
}