using System.Text.Json;
using Akka.Actor;
using Akka.TestKit.Xunit2;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging.Abstractions;
using NSubstitute;
using ZB.MOM.WW.ScadaBridge.Commons.Interfaces.Repositories;
using ZB.MOM.WW.ScadaBridge.Commons.Messages.Management;
using ZB.MOM.WW.ScadaBridge.Commons.Types.Audit;

namespace ZB.MOM.WW.ScadaBridge.ManagementService.Tests;

/// <summary>
/// The <c>VerifyAuditChainHeads</c> management command (ScadaBridge#107 item 1): role gate,
/// site-scope refusal, input bounds, and the verdicts reaching the wire with enums as names.
/// </summary>
public class VerifyAuditChainHeadsCommandTests : TestKit
{
    private readonly IAuditChainHeadStore _store = Substitute.For<IAuditChainHeadStore>();

    private static readonly AuditChainHeadRecord Record = new(
        1, "2026-05", 12, new string('a', 64), null, null, 12, 0,
        new DateTime(2026, 5, 3, 0, 0, 0, DateTimeKind.Utc), new DateTime(2026, 5, 3, 1, 0, 0, DateTimeKind.Utc), "central-a");

    private IActorRef CreateActor()
    {
        var services = new ServiceCollection().AddTestConfigurationTransaction();
        services.AddScoped(_ => _store);
        return Sys.ActorOf(Props.Create(() => new ManagementActor(
            services.BuildServiceProvider(), NullLogger<ManagementActor>.Instance)));
    }

    private static ManagementEnvelope Envelope(object command, string[] sites, params string[] roles) =>
        new(new AuthenticatedUser("u", "U", roles, sites), command, Guid.NewGuid().ToString("N"));

    /// <summary>A Viewer gets the store's verdicts; the records reach the store unchanged.</summary>
    [Fact]
    public void Viewer_GetsTheVerdicts_ForTheSuppliedRecords()
    {
        var check = new AuditChainHeadCheck("2026-05", 12, Record.ExportedAtUtc, "central-a",
            AuditChainHeadStatus.Mismatch, 12, "rewritten");
        _store.VerifyExportedHeadsAsync(Arg.Any<IReadOnlyList<AuditChainHeadRecord>>(), Arg.Any<CancellationToken>())
            .Returns(new AuditChainHeadVerificationResult(false, 1, [check]));

        CreateActor().Tell(Envelope(new VerifyAuditChainHeadsCommand([Record]), [], "Viewer"));

        var response = ExpectMsg<ManagementSuccess>(TimeSpan.FromSeconds(5));
        using var json = JsonDocument.Parse(response.JsonData);
        Assert.False(json.RootElement.GetProperty("verified").GetBoolean());
        Assert.Equal("Mismatch", json.RootElement.GetProperty("checks")[0].GetProperty("status").GetString());
        _store.Received(1).VerifyExportedHeadsAsync(
            Arg.Is<IReadOnlyList<AuditChainHeadRecord>>(r => r.Count == 1 && r[0] == Record), Arg.Any<CancellationToken>());
    }

    /// <summary>A Designer/Deployer without an OperationalAudit role is refused.</summary>
    [Fact]
    public void NonAuditRole_IsUnauthorized()
    {
        CreateActor().Tell(Envelope(new VerifyAuditChainHeadsCommand([Record]), [], "Designer", "Deployer"));

        ExpectMsg<ManagementUnauthorized>(TimeSpan.FromSeconds(5));
        _store.DidNotReceiveWithAnyArgs().VerifyExportedHeadsAsync(default!, default);
    }

    /// <summary>A site-scoped Viewer is refused: the chain spans every site.</summary>
    [Fact]
    public void SiteScopedViewer_IsRefused()
    {
        CreateActor().Tell(Envelope(new VerifyAuditChainHeadsCommand([Record]), ["3"], "Viewer"));

        var response = ExpectMsg<ManagementUnauthorized>(TimeSpan.FromSeconds(5));
        Assert.Contains("spans every site", response.Message);
        _store.DidNotReceiveWithAnyArgs().VerifyExportedHeadsAsync(default!, default);
    }

    /// <summary>No records, or more than the cap, is a caller error.</summary>
    /// <param name="count">Records supplied.</param>
    [Theory]
    [InlineData(0)]
    [InlineData(ManagementActor.MaxChainHeadRecords + 1)]
    public void EmptyOrOversizedInput_IsInvalidArgument(int count)
    {
        CreateActor().Tell(Envelope(
            new VerifyAuditChainHeadsCommand(Enumerable.Repeat(Record, count).ToList()), [], "Administrator"));

        var response = ExpectMsg<ManagementError>(TimeSpan.FromSeconds(5));
        Assert.Equal("INVALID_ARGUMENT", response.ErrorCode);
        _store.DidNotReceiveWithAnyArgs().VerifyExportedHeadsAsync(default!, default);
    }

    /// <summary>A chain lock that cannot be had surfaces as CHAIN_BUSY.</summary>
    [Fact]
    public void BusyChain_IsChainBusy()
    {
        _store.VerifyExportedHeadsAsync(Arg.Any<IReadOnlyList<AuditChainHeadRecord>>(), Arg.Any<CancellationToken>())
            .Returns<Task<AuditChainHeadVerificationResult>>(_ => throw new TimeoutException("busy"));

        CreateActor().Tell(Envelope(new VerifyAuditChainHeadsCommand([Record]), [], "Administrator"));

        Assert.Equal("CHAIN_BUSY", ExpectMsg<ManagementError>(TimeSpan.FromSeconds(5)).ErrorCode);
    }

    /// <summary>Runs under the long-running Ask timeout.</summary>
    [Fact]
    public void VerifyAuditChainHeads_UsesLongRunningAskTimeout()
    {
        Assert.Equal(TimeSpan.FromMinutes(5),
            ManagementEndpoints.ResolveAskTimeout(new ManagementServiceOptions(), typeof(VerifyAuditChainHeadsCommand)));
    }
}