using Akka.Actor;
using Akka.TestKit.Xunit2;
using Microsoft.CodeAnalysis.CSharp.Scripting;
using Microsoft.CodeAnalysis.Scripting;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Logging.Abstractions;
using ZB.MOM.WW.ScadaBridge.Commons.Messages.Streaming;
using ZB.MOM.WW.ScadaBridge.Commons.Types.Flattening;
using ZB.MOM.WW.ScadaBridge.SiteRuntime.Actors;
using ZB.MOM.WW.ScadaBridge.SiteRuntime.Scripts;

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

/// <summary>
/// Final review M6: an alarm on-trigger run's <c>ScriptRuntimeContext</c> was built without a
/// <c>sourceScript</c>, so the context's <c>_logTarget</c> — which names the script on every
/// <c>Log.*</c> line and on the run's trace rows — fell back to the INSTANCE name. The launcher now
/// passes the same <c>AlarmActor:{alarmName}</c> source key it already uses for this alarm's site
/// events, from which the context derives the alarm's own name.
/// </summary>
public class AlarmScriptLogTargetTests : TestKit, IDisposable
{
    private sealed record Entry(LogLevel Level, string Message);

    /// <summary>A minimal recording logger — the alarm path hands its own ILogger down to the script logger.</summary>
    private sealed class RecordingLogger<T> : ILogger<T>
    {
        public List<Entry> Entries { get; } = [];

        public IDisposable? BeginScope<TState>(TState state) where TState : notnull => null;

        public bool IsEnabled(LogLevel logLevel) => true;

        public void Log<TState>(LogLevel level, EventId eventId, TState state, Exception? exception, Func<TState, Exception?, string> formatter)
        {
            lock (Entries) Entries.Add(new Entry(level, formatter(state, exception)));
        }
    }

    private readonly SharedScriptLibrary _sharedLibrary = new(
        new ScriptCompilationService(NullLogger<ScriptCompilationService>.Instance),
        NullLogger<SharedScriptLibrary>.Instance);

    void IDisposable.Dispose() => Shutdown();

    [Fact]
    public void AlarmOnTriggerRun_AttributesItsLogLinesToTheALARM_NotJustTheInstance()
    {
        var options = new SiteRuntimeOptions
        {
            ScriptExecutionTimeoutSeconds = 10,
            MaxScriptCallDepth = 10,
        };
        var scriptOptions = ScriptOptions.Default
            .WithReferences(typeof(object).Assembly, typeof(Enumerable).Assembly, typeof(ScriptGlobals).Assembly)
            .WithImports("System", "System.Threading.Tasks");
        var compiled = CSharpScript.Create<object?>("Log.Info(\"alarm handler ran\"); return null;", scriptOptions, typeof(ScriptGlobals));
        compiled.Compile();

        var logger = new RecordingLogger<AlarmActor>();
        using var scheduler = new ScriptExecutionScheduler(1);
        var config = new ResolvedAlarm
        {
            CanonicalName = "HighTemp",
            TriggerType = "ValueMatch",
            TriggerConfiguration = "{\"attributeName\":\"Status\",\"matchValue\":\"Critical\"}",
            PriorityLevel = 100,
        };
        var alarm = ActorOfAsTestActorRef<AlarmActor>(
            Props.Create(() => new AlarmActor(
                "HighTemp", "Inst1", CreateTestProbe().Ref, config, compiled, _sharedLibrary, options,
                logger, null, null, null, null, null, scheduler, null)),
            "alarm-logtarget-" + Guid.NewGuid().ToString("N"));

        alarm.Tell(new AttributeValueChanged("Inst1", "Status", "Status", "Critical", "Good", DateTimeOffset.UtcNow));

        AwaitAssert(
            () =>
            {
                Entry[] snapshot;
                lock (logger.Entries) snapshot = [.. logger.Entries];
                // "[script] {Instance}/{Script} {ExecutionId}: {Message}" — the script half is the
                // alarm's name because the launcher passed "AlarmActor:HighTemp" as the source.
                Assert.Contains(snapshot, e => e.Message.StartsWith("[script] Inst1/HighTemp ", StringComparison.Ordinal)
                    && e.Message.EndsWith(": alarm handler ran", StringComparison.Ordinal));
            },
            TimeSpan.FromSeconds(15));
    }
}