using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Core.Abstractions;
using ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.PlcFamilies;

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

/// <summary>#646: indirect addresses (N7:[N7:0], N[N7:0]:5) resolve at read/write time.</summary>
[Trait("Category", "Unit")]
public sealed class AbLegacyIndirectAddressingTests
{
    private const string Host = "ab://10.0.0.5/1,0";

    private static async Task<(AbLegacyDriver drv, FakeAbLegacyTagFactory factory)> NewDriverAsync(
        params AbLegacyTagDefinition[] tags)
    {
        var factory = new FakeAbLegacyTagFactory();
        var drv = new AbLegacyDriver(new AbLegacyDriverOptions
        {
            Devices = [new AbLegacyDeviceOptions(Host, AbLegacyPlcFamily.Slc500)],
            RawTags = AbLegacyRawTags.Entries(tags),
            Probe = new AbLegacyProbeOptions { Enabled = false },
        }, "drv-1", factory);
        await drv.InitializeAsync("{}", CancellationToken.None);
        return (drv, factory);
    }

    private static void Seed(FakeAbLegacyTagFactory f, params (string name, object value)[] values)
    {
        var map = values.ToDictionary(v => v.name, v => v.value, StringComparer.OrdinalIgnoreCase);
        f.Customise = p => new FakeAbLegacyTag(p) { Value = map.TryGetValue(p.TagName, out var v) ? v : 0 };
    }

    [Fact]
    public async Task Word_indirect_reads_index_then_composed_address()
    {
        var (drv, f) = await NewDriverAsync(new AbLegacyTagDefinition("Ind", Host, "N7:[N7:0]", AbLegacyDataType.Int));
        Seed(f, ("N7:0", (short)5), ("N7:5", (short)42));

        var r = (await drv.ReadAsync(["Ind"], CancellationToken.None)).Single();

        r.StatusCode.ShouldBe(AbLegacyStatusMapper.Good);
        r.Value.ShouldBe((short)42);
        f.Tags["N7:0"].ReadCount.ShouldBe(1);
        f.Tags["N7:5"].ReadCount.ShouldBe(1);
        f.Tags.Keys.ShouldNotContain(k => k.Contains('['));
    }

    [Fact]
    public async Task File_indirect_resolves_the_file_number()
    {
        var (drv, f) = await NewDriverAsync(new AbLegacyTagDefinition("Ind", Host, "N[N7:0]:5", AbLegacyDataType.Int));
        Seed(f, ("N7:0", (short)9), ("N9:5", (short)77));

        var r = (await drv.ReadAsync(["Ind"], CancellationToken.None)).Single();

        r.StatusCode.ShouldBe(AbLegacyStatusMapper.Good);
        r.Value.ShouldBe((short)77);
        f.Tags.ContainsKey("N9:5").ShouldBeTrue();
    }

    [Fact]
    public async Task Index_is_re_read_every_poll_never_cached()
    {
        var (drv, f) = await NewDriverAsync(new AbLegacyTagDefinition("Ind", Host, "N7:[N7:0]", AbLegacyDataType.Int));
        Seed(f, ("N7:0", (short)5), ("N7:5", (short)42), ("N7:6", (short)43));

        (await drv.ReadAsync(["Ind"], CancellationToken.None)).Single().Value.ShouldBe((short)42);
        f.Tags["N7:0"].Value = (short)6;
        (await drv.ReadAsync(["Ind"], CancellationToken.None)).Single().Value.ShouldBe((short)43);

        f.Tags["N7:0"].ReadCount.ShouldBe(2);
        // the stale resolution's handle is released when the index moves
        f.Tags["N7:5"].Disposed.ShouldBeTrue();
    }

    [Theory]
    [InlineData(-1)]
    [InlineData(256)]
    [InlineData(30000)]
    public async Task Out_of_range_index_is_BadOutOfRange_without_health_impact(int index)
    {
        var (drv, f) = await NewDriverAsync(new AbLegacyTagDefinition("Ind", Host, "N7:[N7:0]", AbLegacyDataType.Int));
        Seed(f, ("N7:0", (short)index));

        var r = (await drv.ReadAsync(["Ind"], CancellationToken.None)).Single();

        r.StatusCode.ShouldBe(AbLegacyStatusMapper.BadOutOfRange);
        drv.GetHealth().State.ShouldNotBe(DriverState.Degraded);
        f.Tags.Keys.ShouldNotContain(k => k.StartsWith("N7:") && k != "N7:0");
    }

    [Fact]
    public async Task Inner_read_failure_propagates_its_status()
    {
        var (drv, f) = await NewDriverAsync(new AbLegacyTagDefinition("Ind", Host, "N7:[N7:0]", AbLegacyDataType.Int));
        f.Customise = p => new FakeAbLegacyTag(p) { Value = (short)5, Status = p.TagName == "N7:0" ? -14 : 0 };

        var r = (await drv.ReadAsync(["Ind"], CancellationToken.None)).Single();

        r.StatusCode.ShouldNotBe(AbLegacyStatusMapper.Good);
        r.StatusCode.ShouldNotBe(AbLegacyStatusMapper.BadOutOfRange);
        f.Tags.ContainsKey("N7:5").ShouldBeFalse();
    }

    [Fact]
    public async Task Write_resolves_index_then_writes_the_composed_address()
    {
        var (drv, f) = await NewDriverAsync(new AbLegacyTagDefinition("Ind", Host, "N7:[N7:0]", AbLegacyDataType.Int, Writable: true));
        Seed(f, ("N7:0", (short)5));

        var w = (await drv.WriteAsync([new WriteRequest("Ind", 99)], CancellationToken.None)).Single();

        w.StatusCode.ShouldBe(AbLegacyStatusMapper.Good);
        f.Tags["N7:5"].WriteCount.ShouldBe(1);
        f.Tags["N7:5"].Value.ShouldBe((short)99);
        f.Tags["N7:0"].WriteCount.ShouldBe(0);
    }

    [Fact]
    public async Task Write_with_bad_index_is_BadOutOfRange_and_writes_nothing()
    {
        var (drv, f) = await NewDriverAsync(new AbLegacyTagDefinition("Ind", Host, "N7:[N7:0]", AbLegacyDataType.Int, Writable: true));
        Seed(f, ("N7:0", (short)-3));

        var w = (await drv.WriteAsync([new WriteRequest("Ind", 1)], CancellationToken.None)).Single();

        w.StatusCode.ShouldBe(AbLegacyStatusMapper.BadOutOfRange);
        f.Tags.Values.ShouldAllBe(t => t.WriteCount == 0);
    }
}