using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Core.Abstractions;
using ZB.MOM.WW.OtOpcUa.Core.Scripting;

namespace ZB.MOM.WW.OtOpcUa.ScriptWorker.Tests;

/// <summary>
///     lmxopcua#780 design §13 "Parity": the same script, through <see cref="InProcessScriptRunner"/> (today's guard)
///     and through the worker, gives the same status, reason, value and exact CLR value type.
/// </summary>
[Collection(ScriptWorkerCollection.Name)]
[Trait("Category", "ScriptWorker")]
public sealed class ParityTests
{
    private static CancellationToken Ct => TestContext.Current.CancellationToken;

    public static TheoryData<string, string> Cases() => new()
    {
        { "arithmetic", "return 1 + 2;" },
        { "string", "return \"a\" + ctx.GetTag(\"x\").Value;" },
        { "throw", "throw new System.InvalidOperationException(\"boom\");" },
        { "compile error", "return undefinedThing;" },
        { "sandbox violation", "return System.IO.File.Exists(\"x\");" },
        { "missing input status", "return ctx.GetTag(\"missing\").StatusCode;" },
        { "input status", "return ctx.GetTag(\"x\").StatusCode;" },
        { "source timestamp", "return ctx.GetTag(\"x\").SourceTimestampUtc;" },
        { "clock", "return ctx.Now > new System.DateTime(2000, 1, 1);" },
        { "null", "return null;" },
        { "array", "return new double[] { 1.5, 2.5 };" },
        { "cast of wrong type", "return (short)ctx.GetTag(\"x\").Value;" },
    };

    private static readonly IReadOnlyDictionary<string, DataValueSnapshot> Inputs =
        new Dictionary<string, DataValueSnapshot>(StringComparer.Ordinal)
        {
            ["x"] = new DataValueSnapshot(5, 0x40000000u, new DateTime(2026, 1, 2, 3, 4, 5, DateTimeKind.Utc), DateTime.UtcNow),
        };

    [Theory]
    [MemberData(nameof(Cases))]
    public async Task In_and_out_of_process_agree(string name, string source)
    {
        using var inProcess = new InProcessScriptRunner();
        await using var outOfProcess = Scripts.Runner(Scripts.Options());
        var invocation = Scripts.Vt(name, source, inputs: Inputs);

        var expected = await inProcess.RunAsync(invocation, Ct);
        var actual = await outOfProcess.RunAsync(invocation, Ct);

        actual.Status.ShouldBe(expected.Status, $"{name}: {actual.Reason} vs {expected.Reason}");
        actual.Reason.ShouldBe(expected.Reason);
        Same(actual.Value, expected.Value, name);
    }

    public static TheoryData<string, object> Typed() => new()
    {
        { "bool", true }, { "sbyte", (sbyte)-2 }, { "byte", (byte)2 }, { "short", (short)-3 }, { "ushort", (ushort)3 },
        { "int", -4 }, { "uint", 4u }, { "long", -5L }, { "ulong", 5UL }, { "float", 1.25f }, { "double", 2.5 },
        { "string", "s" }, { "System.DateTime", new DateTime(2026, 11, 9, 0, 0, 0, DateTimeKind.Utc) },
    };

    /// <summary>
    ///     Unboxing parity (pins design assumption A-7): <c>(T)ctx.GetTag("x").Value</c> works out of process for every
    ///     tag type, which needs the exact boxed CLR type to survive the wire.
    /// </summary>
    [Theory]
    [MemberData(nameof(Typed))]
    public async Task Unboxing_to_the_exact_type_matches(string typeName, object value)
    {
        using var inProcess = new InProcessScriptRunner();
        await using var outOfProcess = Scripts.Runner(Scripts.Options());
        var invocation = Scripts.Vt("unbox-" + typeName, $"var v = ({typeName})ctx.GetTag(\"x\").Value; return v;",
            inputs: Scripts.Input("x", value));

        var expected = await inProcess.RunAsync(invocation, Ct);
        var actual = await outOfProcess.RunAsync(invocation, Ct);
        expected.Status.ShouldBe(ScriptRunStatus.Ok, expected.Reason);
        actual.Status.ShouldBe(ScriptRunStatus.Ok, actual.Reason);
        Same(actual.Value, expected.Value, typeName);
    }

    private static void Same(object? actual, object? expected, string because)
    {
        if (expected is null)
        {
            actual.ShouldBeNull(because);
            return;
        }
        actual.ShouldNotBeNull(because);
        actual.GetType().ShouldBe(expected.GetType(), because);
        if (expected is Array array) ((Array)actual).Cast<object?>().ShouldBe(array.Cast<object?>(), because);
        else actual.ShouldBe(expected, because);
    }
}