using MxGateway.Contracts.Proto;
using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Driver.Galaxy.Runtime;

namespace ZB.MOM.WW.OtOpcUa.Driver.Galaxy.Tests.Runtime;

/// <summary>
///     Exhaustive table-driven tests for <see cref="StatusCodeMap"/>. Pinning the byte→uint
///     mapping here protects against accidental drift — every Galaxy deployment that
///     reaches the parity matrix in PR 5.2 depends on these specific OPC UA StatusCode
///     values matching the legacy <c>HistorianQualityMapper</c> output.
/// </summary>
public sealed class StatusCodeMapTests
{
    [Theory]
    [InlineData((byte)192, 0x00000000u)]   // Good
    [InlineData((byte)216, 0x00D80000u)]   // Good_LocalOverride
    [InlineData((byte)64,  0x40000000u)]   // Uncertain
    [InlineData((byte)68,  0x40A40000u)]   // Uncertain_LastUsableValue
    [InlineData((byte)80,  0x408D0000u)]   // Uncertain_SensorNotAccurate
    [InlineData((byte)84,  0x408E0000u)]   // Uncertain_EngineeringUnitsExceeded
    [InlineData((byte)88,  0x408F0000u)]   // Uncertain_SubNormal
    [InlineData((byte)0,   0x80000000u)]   // Bad
    [InlineData((byte)4,   0x80890000u)]   // Bad_ConfigurationError
    [InlineData((byte)8,   0x808A0000u)]   // Bad_NotConnected
    [InlineData((byte)12,  0x808B0000u)]   // Bad_DeviceFailure
    [InlineData((byte)16,  0x808C0000u)]   // Bad_SensorFailure
    [InlineData((byte)20,  0x80050000u)]   // Bad_CommunicationError
    [InlineData((byte)24,  0x808D0000u)]   // Bad_OutOfService
    [InlineData((byte)32,  0x80320000u)]   // Bad_WaitingForInitialData
    public void FromQualityByte_KnownValues_MapToOpcUaStatusCode(byte input, uint expected)
    {
        StatusCodeMap.FromQualityByte(input).ShouldBe(expected);
    }

    [Theory]
    [InlineData((byte)200)]  // Unknown Good — falls back to category bucket
    [InlineData((byte)100)]  // Unknown Uncertain
    [InlineData((byte)40)]   // Unknown Bad
    public void FromQualityByte_UnknownValues_FallBackToCategoryBucket(byte input)
    {
        var mapped = StatusCodeMap.FromQualityByte(input);
        if (input >= 192) mapped.ShouldBe(StatusCodeMap.Good);
        else if (input >= 64) mapped.ShouldBe(StatusCodeMap.Uncertain);
        else mapped.ShouldBe(StatusCodeMap.Bad);
    }

    [Fact]
    public void FromMxStatus_NullStatus_IsGood()
    {
        StatusCodeMap.FromMxStatus(null).ShouldBe(StatusCodeMap.Good);
    }

    [Fact]
    public void FromMxStatus_SuccessNonZero_IsGood()
    {
        var s = new MxStatusProxy { Success = 1 };
        StatusCodeMap.FromMxStatus(s).ShouldBe(StatusCodeMap.Good);
    }

    [Fact]
    public void FromMxStatus_SuccessZero_DetailKnown_MapsToSpecificCode()
    {
        var s = new MxStatusProxy { Success = 0, Detail = 8 /* Bad_NotConnected */ };
        StatusCodeMap.FromMxStatus(s).ShouldBe(StatusCodeMap.BadNotConnected);
    }

    [Fact]
    public void FromMxStatus_SuccessZero_DetailZero_DetectedByNonZero_IsCommunicationError()
    {
        var s = new MxStatusProxy { Success = 0, Detail = 0, RawDetectedBy = 3 };
        StatusCodeMap.FromMxStatus(s).ShouldBe(StatusCodeMap.BadCommunicationError);
    }

    [Fact]
    public void FromMxStatus_SuccessZero_AllZero_IsBad()
    {
        var s = new MxStatusProxy();
        StatusCodeMap.FromMxStatus(s).ShouldBe(StatusCodeMap.Bad);
    }

    [Fact]
    public void TopByteCategoryBits_StayWithinOpcUaConvention()
    {
        // Sanity check that every Bad code we mint actually has the Bad top byte (0x80…),
        // every Uncertain has 0x40…, every Good has 0x00…. Pins the OPC UA Part 4 invariant.
        StatusCodeMap.Good.ShouldBeLessThan(0x40000000u);
        StatusCodeMap.GoodLocalOverride.ShouldBeLessThan(0x40000000u);

        ((StatusCodeMap.Uncertain >> 30) & 0x3u).ShouldBe(1u);
        ((StatusCodeMap.UncertainLastUsableValue >> 30) & 0x3u).ShouldBe(1u);

        ((StatusCodeMap.Bad >> 30) & 0x3u).ShouldBe(2u);
        ((StatusCodeMap.BadNotConnected >> 30) & 0x3u).ShouldBe(2u);
        ((StatusCodeMap.BadOutOfService >> 30) & 0x3u).ShouldBe(2u);
    }
}