using System.Reflection;
using System.Text.Json;
using Akka.Actor;
using Akka.TestKit.Xunit2;
using Microsoft.Extensions.Logging.Abstractions;
using Serilog.Context;
using ZB.MOM.WW.ScadaBridge.Commons.Messages.DataConnection;
using ZB.MOM.WW.ScadaBridge.Commons.Messages.Instance;
using ZB.MOM.WW.ScadaBridge.Commons.Observability;
using ZB.MOM.WW.ScadaBridge.Commons.Types.Flattening;
using ZB.MOM.WW.ScadaBridge.SiteRuntime.Actors;
using ZB.MOM.WW.ScadaBridge.SiteRuntime.Messages;
using ZB.MOM.WW.ScadaBridge.SiteRuntime.Persistence;
using ZB.MOM.WW.ScadaBridge.SiteRuntime.Scripts;
using ZB.MOM.WW.ScadaBridge.TestSupport;

namespace ZB.MOM.WW.ScadaBridge.SiteRuntime.Tests.Logging;

/// <summary>
/// ScadaBridge#56: a log line the Instance Actor (or any other actor serving an execution) writes
/// while handling a message sent on behalf of that execution carries the execution's id, although
/// <c>LogContext</c> itself never crosses the message hop - the id rides the message and the actor
/// re-pushes it per message.
/// </summary>
public class ExecutionLogEnrichmentTests : TestKit, IDisposable
{
    private const string InstanceName = "Enrich1";
    private const string NoDclLine = "cannot be routed";

    private readonly SiteStorageService _storage;
    private readonly ScriptCompilationService _compilationService;
    private readonly SharedScriptLibrary _sharedScriptLibrary;
    private readonly TestLocalDb _localDb;

    /// <summary>Creates a temporary LocalDb-backed site store per test.</summary>
    public ExecutionLogEnrichmentTests()
    {
        _localDb = TestLocalDb.CreateTemp("execution-log-enrichment");
        _storage = new SiteStorageService(_localDb.Db, NullLogger<SiteStorageService>.Instance);
        _storage.InitializeAsync().GetAwaiter().GetResult();
        _compilationService = new ScriptCompilationService(NullLogger<ScriptCompilationService>.Instance);
        _sharedScriptLibrary = new SharedScriptLibrary(
            _compilationService, NullLogger<SharedScriptLibrary>.Instance);
    }

    /// <inheritdoc />
    void IDisposable.Dispose()
    {
        Shutdown();
        var path = _localDb.Path;
        _localDb.Dispose();
        TestLocalDb.DeleteFiles(path);
    }

    private IActorRef StartInstance(Microsoft.Extensions.Logging.ILogger logger, IActorRef? dcl = null)
    {
        var config = new FlattenedConfiguration
        {
            InstanceUniqueName = InstanceName,
            Attributes =
            [
                new ResolvedAttribute
                {
                    CanonicalName = "Speed", Value = "0", DataType = "Int32",
                    DataSourceReference = "ns=2;s=Speed", BoundDataConnectionName = "conn-1"
                },
                new ResolvedAttribute
                {
                    CanonicalName = "Trigger", Value = "0", DataType = "Int32",
                    DataSourceReference = "ns=2;s=Trigger", BoundDataConnectionName = "conn-1"
                }
            ]
        };
        var json = JsonSerializer.Serialize(config);
        return ActorOf(Props.Create(() => new InstanceActor(
            InstanceName, json, _storage, _compilationService, _sharedScriptLibrary, null,
            new SiteRuntimeOptions(), logger, dcl)));
    }

    /// <summary>
    /// A data-sourced write with no DCL logs a warning while the Instance Actor serves it; that
    /// line carries the writing execution's id.
    /// </summary>
    [Fact]
    public void InstanceActor_LineLoggedWhileServingAnExecution_CarriesItsExecutionId()
    {
        var capture = new LogContextCapture();
        var instance = StartInstance(capture);
        var executionId = Guid.NewGuid();

        instance.Tell(new SetStaticAttributeCommand(
            "c1", InstanceName, "Speed", "5", DateTimeOffset.UtcNow, SourceExecutionId: executionId));
        Assert.False(ExpectMsg<SetStaticAttributeResponse>(TimeSpan.FromSeconds(10)).Success);

        Assert.Equal(executionId, capture.ExecutionIdOf(NoDclLine));
    }

    /// <summary>
    /// The id comes from the MESSAGE, never from the sender's ambient context: a message that names
    /// no execution produces an untagged line even when the sending thread had one pushed. (The
    /// positive control is the test above - same command, same line, id on the message.)
    /// </summary>
    [Fact]
    public void InstanceActor_UncorrelatedMessage_DoesNotInheritTheSendersLogContext()
    {
        var capture = new LogContextCapture();
        var instance = StartInstance(capture);

        using (LogContext.PushProperty(ExecutionLogContext.ExecutionIdProperty, Guid.NewGuid()))
        {
            instance.Tell(new SetStaticAttributeCommand("c1", InstanceName, "Speed", "5", DateTimeOffset.UtcNow));
        }
        ExpectMsg<SetStaticAttributeResponse>(TimeSpan.FromSeconds(10));

        Assert.True(capture.Has(NoDclLine));
        Assert.Null(capture.ExecutionIdOf(NoDclLine));
    }

    /// <summary>The scope is popped after the message: the next uncorrelated message logs untagged.</summary>
    [Fact]
    public void InstanceActor_ExecutionScopeEndsWithTheMessage()
    {
        var capture = new LogContextCapture();
        var instance = StartInstance(capture);

        instance.Tell(new SetStaticAttributeCommand(
            "first", InstanceName, "Speed", "5", DateTimeOffset.UtcNow, SourceExecutionId: Guid.NewGuid()));
        ExpectMsg<SetStaticAttributeResponse>(TimeSpan.FromSeconds(10));
        instance.Tell(new SetStaticAttributeCommand("second", InstanceName, "Trigger", "1", DateTimeOffset.UtcNow));
        ExpectMsg<SetStaticAttributeResponse>(TimeSpan.FromSeconds(10));

        var lines = capture.Events.Where(e => e.RenderMessage().Contains(NoDclLine, StringComparison.Ordinal)).ToList();
        Assert.Equal(2, lines.Count);
        Assert.True(lines[0].Properties.ContainsKey(ExecutionLogContext.ExecutionIdProperty));
        Assert.False(lines[1].Properties.ContainsKey(ExecutionLogContext.ExecutionIdProperty));
    }

    /// <summary>
    /// A routed SetAttributes arrives as one <see cref="InstanceSetAttributesRequest"/> that names no
    /// execution; each write inside it does, and its line carries that write's id.
    /// </summary>
    [Fact]
    public void InstanceActor_BatchedWrites_LogUnderEachWritesExecution()
    {
        var capture = new LogContextCapture();
        var instance = StartInstance(capture);
        var executionId = Guid.NewGuid();

        instance.Tell(new InstanceSetAttributesRequest("c1",
        [
            new SetStaticAttributeCommand("w1", InstanceName, "Speed", "5", DateTimeOffset.UtcNow,
                SourceExecutionId: executionId),
        ]));
        ExpectMsg<InstanceSetAttributesResponse>(TimeSpan.FromSeconds(10));

        Assert.Equal(executionId, capture.ExecutionIdOf(NoDclLine));
    }

    /// <summary>A script run stamps its own id on every request it sends the Instance Actor.</summary>
    /// <returns>A task that represents the asynchronous operation.</returns>
    [Fact]
    public async Task ScriptRuntimeContext_StampsItsExecutionIdOnInstanceRequests()
    {
        var probe = CreateTestProbe();
        var executionId = Guid.NewGuid();
        var ctx = new ScriptRuntimeContext(
            probe.Ref, _sharedScriptLibrary,
            currentCallDepth: 0, maxCallDepth: 10, askTimeout: TimeSpan.FromSeconds(5),
            instanceName: InstanceName, logger: NullLogger.Instance,
            executionId: executionId);

        var read = ctx.GetAttribute("Speed");
        var get = probe.ExpectMsg<GetAttributeRequest>(TimeSpan.FromSeconds(5));
        Assert.Equal(executionId, get.SourceExecutionId);
        probe.Reply(new GetAttributeResponse(get.CorrelationId, InstanceName, "Speed", 1, true, "Good", DateTimeOffset.UtcNow));
        await read;

        var call = ctx.WriteBatchAndWait(
            new Dictionary<string, string?> { ["Speed"] = "7" }, "Trigger", "1", "Ack", "1", TimeSpan.FromSeconds(3));
        var batch = probe.ExpectMsg<WriteAttributeBatchRequest>(TimeSpan.FromSeconds(5));
        Assert.Equal(executionId, batch.SourceExecutionId);
        probe.Reply(new WriteAttributeBatchResponse(batch.CorrelationId, true, null));
        var wait = probe.ExpectMsg<WaitForAttributeRequest>(TimeSpan.FromSeconds(5));
        Assert.Equal(executionId, wait.SourceExecutionId);
        probe.Reply(new WaitForAttributeResponse(wait.CorrelationId, Matched: true, "1", "Good", TimedOut: false));
        Assert.True(await call);
    }

    /// <summary>The Instance Actor hands the writing execution's id on to the DCL, single and batch writes alike.</summary>
    [Fact]
    public void InstanceActor_ForwardsTheExecutionIdOnDclWrites()
    {
        var dcl = CreateTestProbe();
        var instance = StartInstance(NullLogger.Instance, dcl.Ref);
        dcl.ExpectMsg<SubscribeTagsRequest>(TimeSpan.FromSeconds(10));
        var single = Guid.NewGuid();
        var batch = Guid.NewGuid();

        instance.Tell(new SetStaticAttributeCommand(
            "c1", InstanceName, "Speed", "5", DateTimeOffset.UtcNow, SourceExecutionId: single));
        Assert.Equal(single, dcl.ExpectMsg<WriteTagRequest>(TimeSpan.FromSeconds(10)).SourceExecutionId);

        instance.Tell(new WriteAttributeBatchRequest(
            "c2", InstanceName, new Dictionary<string, string?> { ["Speed"] = "7" }, "Trigger", "1",
            DateTimeOffset.UtcNow, SourceExecutionId: batch));
        Assert.Equal(batch, dcl.ExpectMsg<WriteTagBatchRequest>(TimeSpan.FromSeconds(10)).SourceExecutionId);
    }

    /// <summary>
    /// Every site actor that serves executions re-pushes the id per message. A behavioural test
    /// covers the Instance Actor (above) and the DCL connection actor (DCL tests); this pins the
    /// hook on the rest so a refactor that drops it is caught.
    /// </summary>
    /// <param name="actorType">The actor type.</param>
    [Theory]
    [InlineData(typeof(InstanceActor))]
    [InlineData(typeof(ScriptActor))]
    [InlineData(typeof(AlarmActor))]
    [InlineData(typeof(DeploymentManagerActor))]
    [InlineData(typeof(ZB.MOM.WW.ScadaBridge.DataConnectionLayer.Actors.DataConnectionManagerActor))]
    [InlineData(typeof(ZB.MOM.WW.ScadaBridge.DataConnectionLayer.Actors.DataConnectionActor))]
    public void ExecutionServingActors_OverrideAroundReceive(Type actorType)
    {
        var method = actorType.GetMethod(
            "AroundReceive", BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.DeclaredOnly);
        Assert.NotNull(method);
    }
}