using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Driver.Ab.Transport.Cip;
namespace ZB.MOM.WW.OtOpcUa.Driver.Ab.Transport.Tests.Wire;

public sealed class CipReplyTests
{
    [Fact]
    public void Parses_success_reply_with_data()
    {
        // 0xCC = reply to Read Tag 0x4C; reserved; status 0; ext size 0; data C4 00 2A 00 00 00
        var r = CipReply.Parse(new byte[] { 0xCC, 0x00, 0x00, 0x00, 0xC4, 0x00, 0x2A, 0x00, 0x00, 0x00 });
        r.Service.ShouldBe((byte)0x4C);
        r.GeneralStatus.ShouldBe((byte)0);
        r.ExtendedStatus.Length.ShouldBe(0);
        r.Data.ToArray().ShouldBe(new byte[] { 0xC4, 0x00, 0x2A, 0x00, 0x00, 0x00 });
    }

    [Fact]
    public void Parses_reply_with_one_extended_word()
    {
        var r = CipReply.Parse(new byte[] { 0xCC, 0x00, 0xFF, 0x01, 0x07, 0x21 });
        r.ExtendedStatus.ToArray().ShouldBe(new ushort[] { 0x2107 });
        r.Status.ShouldBe(AbStatus.TypeMismatch);
    }

    [Fact]
    public void Parses_error_reply_with_two_extended_words()
    {
        var r = CipReply.Parse(new byte[] { 0xCC, 0x00, 0xFF, 0x02, 0x05, 0x21, 0x00, 0x00 });
        r.GeneralStatus.ShouldBe((byte)0xFF);
        r.ExtendedStatus.ToArray().ShouldBe(new ushort[] { 0x2105, 0x0000 });
        r.Data.Length.ShouldBe(0);
        r.Status.ShouldBe(AbStatus.OutOfBounds);
    }

    [Fact]
    public void Truncated_reply_throws_BadReply()
    {
        var ex = Should.Throw<AbTransportException>(() => CipReply.Parse(new byte[] { 0xCC, 0x00 }));
        ex.Status.ShouldBe(AbStatus.BadReply);
    }
}