#nullable enable
using System;
using System.IO;
using System.Linq;
using System.Collections.Generic;
using Newtonsoft.Json;
using UnityEditor;
using UnityEditor.Compilation;
using UnityEngine;
using ShrinkContext;
using ShrinkEventBus;

namespace ShrinkSDK.Inspection.Editor
{
    public static class ShrinkInspectionExport
    {
        private const string DirectoryName = "Artifacts/Inspection";
        /// <summary>Host extensions add explicitly owned Network/Command/Context instances. Remove handlers when the host shuts down.</summary>
        public static event Action<ShrinkInspectionSnapshot>? CaptureHostState;

        [MenuItem("Tools/ShrinkSDK/Inspection/Export compilation inputs")]
        public static void ExportCompilation()
        {
            RequireStableEditor();
            var root = Path.GetFullPath(".");
            var assemblies = CompilationPipeline.GetAssemblies(AssembliesType.Player);
            var loaded = AppDomain.CurrentDomain.GetAssemblies().Where(a => !a.IsDynamic).Select(a => a.GetName().Name).ToHashSet();
            var identityNames = assemblies.Select(a => a.name).Where(loaded.Contains).OrderBy(n => n, StringComparer.Ordinal).ToArray();
            var inputs = assemblies.Select(a => new { Name = a.name, Sources = a.sourceFiles.Select(Path.GetFullPath).ToArray(),
                References = a.allReferences.Select(Path.GetFullPath).Where(File.Exists).ToArray(), Defines = a.defines, Output = Path.GetFullPath(a.outputPath) }).ToArray();
            var ticks = inputs.SelectMany(a => a.Sources.Concat(a.References)).Distinct(StringComparer.OrdinalIgnoreCase)
                .ToDictionary(path => path, path => File.GetLastWriteTimeUtc(path).Ticks);
            Directory.CreateDirectory(DirectoryName);
            File.WriteAllText(DirectoryName + "/compilation.json", JsonConvert.SerializeObject(new { Root = root,
                BuildId = ShrinkInspectionSnapshot.BuildIdentity(identityNames), IdentityAssemblies = identityNames, Assemblies = inputs, SourceTicks = ticks }, Formatting.Indented));
            Debug.Log("Shrink inspection compilation exported: " + Path.GetFullPath(DirectoryName + "/compilation.json"));
        }

        [MenuItem("Tools/ShrinkSDK/Inspection/Export runtime snapshot")]
        public static void ExportRuntime()
        {
            RequireStableEditor();
            var path = DirectoryName + "/compilation.json";
            if (!File.Exists(path)) throw new InvalidOperationException("Export compilation inputs first.");
            var manifest = JsonConvert.DeserializeObject<IdentityManifest>(File.ReadAllText(path))!;
            var snapshot = new ShrinkInspectionSnapshot(ShrinkInspectionSnapshot.BuildIdentity(manifest.IdentityAssemblies));
            snapshot.AddContext("default-context", ShrinkContextDefaults.Default);
            var ordinal = 0;
            foreach (var bus in EventBus.CaptureNamedBuses()) snapshot.AddEventBus("named-bus-" + ordinal++, bus);
            snapshot.Coverage.Add("Default Context and named EventBus instances only; host-owned instances require CaptureHostState registration.");
            CaptureHostState?.Invoke(snapshot);
            File.WriteAllText(DirectoryName + "/runtime.json", snapshot.ToJson());
            Debug.Log("Shrink inspection runtime exported: " + Path.GetFullPath(DirectoryName + "/runtime.json"));
        }
        private static void RequireStableEditor()
        {
            if (EditorApplication.isCompiling || EditorApplication.isUpdating) throw new InvalidOperationException("Wait for Editor compilation/import to finish.");
        }
        private sealed class IdentityManifest { public string[] IdentityAssemblies = Array.Empty<string>(); }
    }
}