using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging.Abstractions;
using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Core.Abstractions;
using ZB.MOM.WW.OtOpcUa.Runtime.Historian;

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

/// <summary>
///     AVEVA's native TimeAverage / Total answer Good-status wrong values until the gateway's interval fix
///     (historiangw#27) is live-verified, so they are refused <c>BadAggregateNotSupported</c> unless
///     <c>ServerHistorian:Gateway:EnableNativeTimeWeighted</c> opts back in.
/// </summary>
public sealed class GatewayNativeTimeWeightedGateTests
{
    private static readonly DateTime T0 = new(2026, 10, 22, 0, 0, 0, DateTimeKind.Utc);
    private static CancellationToken Ct => TestContext.Current.CancellationToken;

    [Theory]
    [InlineData(HistoryAggregateType.TimeAverage)]
    [InlineData(HistoryAggregateType.Total)]
    public async Task By_default_the_native_time_weighted_pair_is_refused_unsent_and_unadvertised(HistoryAggregateType a)
    {
        var fake = new FakeHistorianGatewayClient();
        var ds = new GatewayHistorianDataSource(fake, NullLogger<GatewayHistorianDataSource>.Instance);

        ds.SupportedAggregates.ShouldNotContain(a);
        await Should.ThrowAsync<HistoryAggregateNotSupportedException>(
            () => ds.ReadProcessedAsync("T", T0, T0.AddHours(1), TimeSpan.FromMinutes(1), a, Ct));
        fake.ReadAggregateCallCount.ShouldBe(0);
        fake.TagExistsCallCount.ShouldBe(0);
        ds.GetHealthSnapshot().TotalQueries.ShouldBe(0, "a refused aggregate is a client request, not a backend read");

        // Positive control: a raw-evaluated per-sample aggregate on the same source is still served.
        ds.SupportedAggregates.ShouldContain(HistoryAggregateType.Average);
        var avg = await ds.ReadProcessedAsync("T", T0, T0.AddHours(1), TimeSpan.FromMinutes(30), HistoryAggregateType.Average, Ct);
        avg.Samples.Count.ShouldBe(2);
        fake.ReadRawCallCount.ShouldBeGreaterThan(0);
    }

    [Theory]
    [InlineData(HistoryAggregateType.TimeAverage)]
    [InlineData(HistoryAggregateType.Total)]
    public async Task Opting_in_serves_and_advertises_the_native_pair(HistoryAggregateType a)
    {
        var fake = new FakeHistorianGatewayClient();
        var ds = new GatewayHistorianDataSource(fake, NullLogger<GatewayHistorianDataSource>.Instance, enableNativeTimeWeighted: true);

        ds.SupportedAggregates.ShouldBe(GatewayHistorianDataSource.ServedAggregates);
        await ds.ReadProcessedAsync("T", T0, T0.AddHours(1), TimeSpan.FromMinutes(1), a, Ct);
        fake.ReadAggregateCallCount.ShouldBeGreaterThan(0);
    }

    [Fact]
    public void The_default_set_is_the_ten_raw_evaluated_aggregates()
    {
        var ds = new GatewayHistorianDataSource(new FakeHistorianGatewayClient(), NullLogger<GatewayHistorianDataSource>.Instance);
        ds.SupportedAggregates.Count.ShouldBe(10);
        ds.SupportedAggregates.ShouldBe(GatewayHistorianDataSource.RawEvaluatedAggregates);
        GatewayHistorianDataSource.ServedAggregates.Except(ds.SupportedAggregates).OrderBy(x => x)
            .ShouldBe([HistoryAggregateType.Total, HistoryAggregateType.TimeAverage]);
    }

    [Theory]
    [InlineData(null, false)]
    [InlineData("false", false)]
    [InlineData("true", true)]
    public void The_flag_binds_from_configuration_and_reaches_the_data_source(string? configured, bool expected)
    {
        var values = new Dictionary<string, string?>
        {
            ["ServerHistorian:Enabled"] = "true",
            ["ServerHistorian:Endpoint"] = "https://localhost:5222",
            ["ServerHistorian:ApiKey"] = "histgw_x_y",
        };
        if (configured is not null) values["ServerHistorian:Gateway:EnableNativeTimeWeighted"] = configured;
        var opts = new ConfigurationBuilder().AddInMemoryCollection(values).Build()
            .GetSection(ServerHistorianOptions.SectionName).Get<ServerHistorianOptions>()!;
        using var services = new ServiceCollection().BuildServiceProvider();
        var ds = Assert.IsType<GatewayHistorianDataSource>(GatewayHistorian.CreateDataSource(opts, services));
        ds.SupportedAggregates.Contains(HistoryAggregateType.TimeAverage).ShouldBe(expected);
    }
}