using Akka.Actor;
using Akka.TestKit.Xunit2;
using Microsoft.Extensions.Logging.Abstractions;
using ZB.MOM.WW.Audit;
using ZB.MOM.WW.ScadaBridge.Commons.Messages.Instance;
using ZB.MOM.WW.ScadaBridge.Commons.Messages.ScriptExecution;
using ZB.MOM.WW.ScadaBridge.Commons.Types.Audit;
using ZB.MOM.WW.ScadaBridge.Commons.Types.Debugging;
using IAuditWriter = ZB.MOM.WW.ScadaBridge.Commons.Interfaces.Services.IAuditWriter;
using ZB.MOM.WW.ScadaBridge.SiteRuntime.Scripts;

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

/// <summary>
/// Flow Debugger design 2026-09-05 §5.1/§5.2: a traced <see cref="ScriptRuntimeContext"/>
/// emits <c>ScriptTrace</c> rows for attribute writes and waits (into the inline collector
/// AND the audit writer), stamps <c>Trace</c> on the commands it sends, and inherits the flag
/// into nested calls. An untraced context is byte-for-byte the pre-feature behaviour.
/// </summary>
public class ScriptRuntimeContextTraceEmissionTests : TestKit
{
    private const string InstanceName = "Plant.Pump42";

    private sealed class CapturingAuditWriter : IAuditWriter
    {
        public List<AuditEvent> Events { get; } = new();
        public Task WriteAsync(AuditEvent evt, CancellationToken ct = default)
        {
            lock (Events) Events.Add(evt);
            return Task.CompletedTask;
        }
    }

    private static SharedScriptLibrary NewLibrary() =>
        new(new ScriptCompilationService(NullLogger<ScriptCompilationService>.Instance),
            NullLogger<SharedScriptLibrary>.Instance);

    private static ScriptRuntimeContext CreateContext(
        IActorRef instanceActor, IAuditWriter? writer, bool traced, FlowTraceCollector? collector,
        Guid? executionId = null, Guid? parentExecutionId = null)
        => new(
            instanceActor, NewLibrary(),
            currentCallDepth: 0, maxCallDepth: 10, askTimeout: TimeSpan.FromSeconds(5),
            instanceName: InstanceName, logger: NullLogger.Instance,
            siteId: "site-a", sourceScript: "ScriptActor:A", auditWriter: writer,
            executionId: executionId, parentExecutionId: parentExecutionId, sourceNode: "node-a",
            isTraced: traced, traceCollector: collector);

    [Fact]
    public async Task SetAttribute_WhenTraced_EmitsAttributeWriteRow_AndPassesTraceOnCommand()
    {
        var probe = CreateTestProbe();
        var writer = new CapturingAuditWriter();
        var collector = new FlowTraceCollector();
        var exec = Guid.NewGuid();
        var parent = Guid.NewGuid();
        var ctx = CreateContext(probe.Ref, writer, traced: true, collector, exec, parent);

        var call = ctx.SetAttribute("Setpoint", "42");
        var cmd = probe.ExpectMsg<SetStaticAttributeCommand>(TimeSpan.FromSeconds(5));
        Assert.True(cmd.Trace);
        Assert.Equal(exec, cmd.SourceExecutionId);
        probe.Reply(new SetStaticAttributeResponse(cmd.CorrelationId, InstanceName, "Setpoint", true, null, DateTimeOffset.UtcNow));
        await call;

        var evt = Assert.Single(writer.Events);
        var row = evt.AsRow();
        Assert.Equal("ScriptTrace", evt.Category);
        Assert.Equal("ScriptTrace.AttributeWrite", evt.Action);
        Assert.Equal(exec, row.ExecutionId);
        Assert.Equal(parent, row.ParentExecutionId);
        Assert.Equal("site-a", row.SourceSiteId);
        Assert.Equal("node-a", evt.SourceNode);
        Assert.Equal("Setpoint", evt.Target);
        Assert.Equal(AuditOutcome.Success, evt.Outcome);
        var extra = ScriptTraceExtra.TryParse(row.Extra);
        var write = Assert.Single(extra!.Writes!);
        Assert.Equal(("Setpoint", "42", true), (write.Attribute, write.Written, write.Success));
        Assert.Contains("\"value\":\"42\"", row.RequestSummary);

        Assert.Same(evt, Assert.Single(collector.Snapshot()));
    }

    [Fact]
    public async Task SetAttribute_WhenNotTraced_EmitsNothing_AndCommandTraceFalse()
    {
        var probe = CreateTestProbe();
        var writer = new CapturingAuditWriter();
        var ctx = CreateContext(probe.Ref, writer, traced: false, collector: null);

        var call = ctx.SetAttribute("Setpoint", "42");
        var cmd = probe.ExpectMsg<SetStaticAttributeCommand>(TimeSpan.FromSeconds(5));
        Assert.False(cmd.Trace);
        probe.Reply(new SetStaticAttributeResponse(cmd.CorrelationId, InstanceName, "Setpoint", true, null, DateTimeOffset.UtcNow));
        await call;

        Assert.Empty(writer.Events);
        Assert.False(ctx.IsTraced);
    }

    [Fact]
    public async Task SetAttribute_WhenTraced_FailedWrite_EmitsFailedRow_ThenThrows()
    {
        var probe = CreateTestProbe();
        var writer = new CapturingAuditWriter();
        var ctx = CreateContext(probe.Ref, writer, traced: true, new FlowTraceCollector());

        var call = ctx.SetAttribute("Setpoint", "42");
        var cmd = probe.ExpectMsg<SetStaticAttributeCommand>(TimeSpan.FromSeconds(5));
        probe.Reply(new SetStaticAttributeResponse(cmd.CorrelationId, InstanceName, "Setpoint", false, "device rejected", DateTimeOffset.UtcNow));

        await Assert.ThrowsAsync<InvalidOperationException>(() => call);
        var row = Assert.Single(writer.Events).AsRow();
        Assert.Equal("Failed", row.Status.ToString());
        Assert.Equal("device rejected", row.ErrorMessage);
    }

    [Fact]
    public async Task WaitInternal_WhenTraced_EmitsAttributeWait_WithOutcomeSatisfied()
    {
        var probe = CreateTestProbe();
        var writer = new CapturingAuditWriter();
        var collector = new FlowTraceCollector();
        var ctx = CreateContext(probe.Ref, writer, traced: true, collector);

        var wait = ctx.WaitAttributeFull("Processed", "true", null, TimeSpan.FromSeconds(3));
        var req = probe.ExpectMsg<WaitForAttributeRequest>(TimeSpan.FromSeconds(5));
        probe.Reply(new WaitForAttributeResponse(req.CorrelationId, Matched: true, true, "Good", TimedOut: false));
        var result = await wait;

        Assert.True(result.Matched);
        var evt = Assert.Single(writer.Events);
        Assert.Equal("ScriptTrace.AttributeWait", evt.Action);
        Assert.Equal("Processed", evt.Target);
        var extra = ScriptTraceExtra.TryParse(evt.AsRow().Extra)!;
        Assert.Equal("satisfied", extra.WaitOutcome);
        Assert.Equal("Processed", extra.WaitAttribute);
        Assert.Equal("true", extra.WaitTarget);
        Assert.Equal(3000, extra.WaitTimeoutMs);
        Assert.Equal("true", extra.ObservedValue, ignoreCase: true);
        Assert.Single(collector.Snapshot());
    }

    [Fact]
    public async Task WaitInternal_WhenTraced_Timeout_EmitsFailedRow_WithTimeoutOutcome()
    {
        var probe = CreateTestProbe();
        var writer = new CapturingAuditWriter();
        var ctx = CreateContext(probe.Ref, writer, traced: true, new FlowTraceCollector());

        var wait = ctx.WaitAttribute("Processed", "true", null, TimeSpan.FromSeconds(1));
        var req = probe.ExpectMsg<WaitForAttributeRequest>(TimeSpan.FromSeconds(5));
        probe.Reply(new WaitForAttributeResponse(req.CorrelationId, Matched: false, null, null, TimedOut: true));

        Assert.False(await wait);
        var row = Assert.Single(writer.Events).AsRow();
        Assert.Equal("Failed", row.Status.ToString());
        Assert.Contains("timed out", row.ErrorMessage);
        Assert.Equal("timeout", ScriptTraceExtra.TryParse(row.Extra)!.WaitOutcome);
    }

    [Fact]
    public async Task WaitInternal_WhenNotTraced_EmitsNothing()
    {
        var probe = CreateTestProbe();
        var writer = new CapturingAuditWriter();
        var ctx = CreateContext(probe.Ref, writer, traced: false, collector: null);

        var wait = ctx.WaitAttribute("Processed", "true", null, TimeSpan.FromSeconds(1));
        var req = probe.ExpectMsg<WaitForAttributeRequest>(TimeSpan.FromSeconds(5));
        probe.Reply(new WaitForAttributeResponse(req.CorrelationId, Matched: true, true, "Good", TimedOut: false));
        await wait;

        Assert.Empty(writer.Events);
    }

    [Fact]
    public async Task CallScript_WhenTraced_PropagatesTraceOnScriptCallRequest()
    {
        var probe = CreateTestProbe();
        var ctx = CreateContext(probe.Ref, null, traced: true, new FlowTraceCollector());

        var call = ctx.CallScript("B");
        var req = probe.ExpectMsg<ScriptCallRequest>(TimeSpan.FromSeconds(5));
        Assert.True(req.Trace);
        probe.Reply(new ScriptCallResult(req.CorrelationId, true, null, null));
        await call;

        // The inline shared-script child context inherits the flag too.
        Assert.True(ctx.CreateChildContextForSharedScript(1).IsTraced);
        Assert.False(CreateContext(probe.Ref, null, traced: false, null).CreateChildContextForSharedScript(1).IsTraced);
    }

    [Fact]
    public async Task CallScript_WhenNotTraced_RequestTraceIsFalse()
    {
        var probe = CreateTestProbe();
        var ctx = CreateContext(probe.Ref, null, traced: false, null);

        var call = ctx.CallScript("B");
        var req = probe.ExpectMsg<ScriptCallRequest>(TimeSpan.FromSeconds(5));
        Assert.False(req.Trace);
        probe.Reply(new ScriptCallResult(req.CorrelationId, true, null, null));
        await call;
    }
}