using ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Wire;

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

/// <summary>
///     Loads the raw FOCAS response PDUs under <c>Fixtures/v3/</c> — byte-for-byte captures from a
///     real FANUC 31i-B (Makino, series G431) — and splits them into response blocks with the
///     production <see cref="FocasWireProtocol.ParseResponseBlocks"/>. The <c>live-*</c> captures
///     were taken by the sister ignitionoee FOCAS driver's read-only probes of Z-34184 (2026-08-12)
///     and are shared verbatim; the <c>ref-*</c> ones are this repo's own 2026-06-25 capture.
/// </summary>
internal static class WireFixtures
{
    private const int PduHeaderLength = 10;

    /// <summary>Every response block of the named capture, in wire order.</summary>
    /// <param name="name">File name under <c>Fixtures/v3/</c>.</param>
    /// <returns>The parsed response blocks.</returns>
    public static IReadOnlyList<ResponseBlock> Blocks(string name)
    {
        var raw = File.ReadAllBytes(Path.Combine(AppContext.BaseDirectory, "Fixtures", "v3", name));
        return FocasWireProtocol.ParseResponseBlocks(raw.AsSpan(PduHeaderLength));
    }

    /// <summary>The payload of the first block carrying <paramref name="command"/>.</summary>
    /// <param name="name">File name under <c>Fixtures/v3/</c>.</param>
    /// <param name="command">The FOCAS command id to locate.</param>
    /// <returns>That block's payload bytes.</returns>
    public static byte[] Payload(string name, ushort command) =>
        Blocks(name).First(b => b.Command == command).Payload;
}