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

namespace ZB.MOM.WW.OtOpcUa.Driver.Historian.QuestDb.Tests;

public sealed class QuestDbHistorianProviderTests
{
    private static QuestDbHistorianProvider Make() => new(new QuestDbHistorianOptions
    {
        ConnectionString = "Host=localhost;Port=18812;Username=admin;Password=quest;Database=qdb;ServerCompatibilityMode=NoTypeLoading",
    });

    [Fact]
    public void Name_and_all_six_kinds()
    {
        var p = Make();
        p.Name.ShouldBe("QuestDb");
        p.SupportedKinds.ShouldBe(Enum.GetValues<HistorianValueKind>(), ignoreOrder: true);
        p.SupportedKinds.Count.ShouldBe(6);
    }

    [Fact]
    public void Creates_all_five_seams_without_touching_questdb()
    {
        var sp = new NullSp();
        var p = Make();
        p.CreateDataSource(sp).ShouldBeOfType<QuestDbHistorianDataSource>();
        p.CreateValueWriter(sp).ShouldBeOfType<QuestDbHistorianValueWriter>();
        p.CreateAlarmWriter(sp).ShouldBeOfType<QuestDbAlarmHistorianWriter>();
        p.CreateProvisioning(sp).ShouldBeOfType<QuestDbTagProvisioner>();
        p.CreateUpdater(sp).ShouldBeOfType<QuestDbHistorianDataUpdater>();
    }

    [Fact]
    public void Supported_kinds_are_a_frozen_set() =>
        Make().SupportedKinds.ShouldBeAssignableTo<System.Collections.Frozen.FrozenSet<HistorianValueKind>>();

    /// <summary>
    ///     An invalid table prefix must not fail provider construction (the host resolves the provider even when no
    ///     consumer is enabled); it surfaces only when a seam is actually built.
    /// </summary>
    [Fact]
    public void An_invalid_prefix_fails_only_when_a_seam_is_built()
    {
        var p = new QuestDbHistorianProvider(new QuestDbHistorianOptions { ConnectionString = "Host=x", TablePrefix = "bad;prefix" });
        p.Name.ShouldBe("QuestDb");
        Should.Throw<ArgumentException>(() => p.CreateDataSource(new NullSp()));
    }

    [Fact]
    public void Every_seam_shares_one_connection_bootstrapper_catalog_and_wal_wait()
    {
        var sp = new NullSp();
        var p = Make();
        var a = (QuestDbHistorianDataSource)p.CreateDataSource(sp);
        var b = (QuestDbHistorianDataSource)p.CreateDataSource(sp);
        var w = p.CreateValueWriter(sp);
        var u = p.CreateUpdater(sp)!;
        var prov = p.CreateProvisioning(sp);
        var alarm = p.CreateAlarmWriter(sp);

        Field(a, "_conn").ShouldBeSameAs(Field(b, "_conn"));
        Field(a, "_conn").ShouldBeSameAs(Field(w, "_conn"));
        Field(a, "_conn").ShouldBeSameAs(Field(u, "_conn"));
        Field(a, "_conn").ShouldBeSameAs(Field(alarm, "_conn"));
        Field(a, "_bootstrap").ShouldBeSameAs(Field(b, "_bootstrap"));
        Field(a, "_bootstrap").ShouldBeSameAs(Field(prov, "_bootstrap"));
        Field(a, "_bootstrap").ShouldBeSameAs(Field(alarm, "_bootstrap"));
        Field(a, "_catalog").ShouldBeSameAs(Field(b, "_catalog"));
        Field(a, "_catalog").ShouldBeSameAs(Field(w, "_catalog"));
        Field(a, "_catalog").ShouldBeSameAs(Field(u, "_tags"));
        Field(a, "_catalog").ShouldBeSameAs(Field(prov, "_catalog"));
        Field(w, "_wal").ShouldBeSameAs(Field(u, "_wal"));
        Field(w, "_wal").ShouldBeSameAs(Field(prov, "_wal"));
        Field(w, "_wal").ShouldBeSameAs(Field(alarm, "_wal"));
    }

    [Fact]
    public async Task Disposing_the_provider_disposes_the_shared_pool_and_is_idempotent()
    {
        var sp = new NullSp();
        var p = Make();
        var conn = (QuestDbConnection)Field(p.CreateDataSource(sp), "_conn")!;
        var pool = (Npgsql.NpgsqlDataSource)Field(conn, "_dataSource")!;
        await p.DisposeAsync();
        Should.Throw<ObjectDisposedException>(() => pool.CreateConnection().Open());
        await p.DisposeAsync();
        p.Dispose();
        Should.Throw<ObjectDisposedException>(() => p.CreateDataSource(sp));
    }

    [Fact]
    public async Task Disposing_an_unused_provider_is_a_no_op() => await Make().DisposeAsync();

    [Fact]
    public void The_constructor_rejects_null_options() =>
        Should.Throw<ArgumentNullException>(() => new QuestDbHistorianProvider(null!));

    private static object? Field(object o, string name) =>
        o.GetType().GetField(name, System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic)!.GetValue(o);

    private sealed class NullSp : IServiceProvider
    {
        public object? GetService(Type serviceType) => null;
    }
}