using UnityEditor;
using System.Collections.Generic;

namespace FBXImporter
{
    public class FBXDropWatcher : AssetPostprocessor
    {
        static readonly List<string> _pendingNewFBX = new List<string>();
        static bool _dialogScheduled = false;

        bool ShouldWatch()
        {
            return assetPath.StartsWith("Assets/")
                && assetPath.EndsWith(".fbx", System.StringComparison.OrdinalIgnoreCase)
                && !ProcessedFBXRegistry.IsRegistered(assetPath);
        }

        void OnPreprocessModel()
        {
            if (!ShouldWatch()) return;

            var importer = assetImporter as ModelImporter;
            importer.importCameras     = false;
            importer.importLights      = false;
            importer.importNormals     = ModelImporterNormals.Import;
            importer.importTangents    = ModelImporterTangents.CalculateMikk;
            importer.importBlendShapes = true;
            importer.importVisibility  = true;
            importer.materialImportMode = ModelImporterMaterialImportMode.ImportViaMaterialDescription;
            importer.materialLocation   = ModelImporterMaterialLocation.External;
            importer.materialName       = ModelImporterMaterialName.BasedOnMaterialName;
            importer.materialSearch     = ModelImporterMaterialSearch.RecursiveUp;
            importer.useFileScale = true;
            importer.globalScale  = 1f;
        }

        void OnPostprocessModel(UnityEngine.GameObject root)
        {
            if (!ShouldWatch()) return;

            if (!_pendingNewFBX.Contains(assetPath))
                _pendingNewFBX.Add(assetPath);

            if (!_dialogScheduled)
            {
                _dialogScheduled = true;
                EditorApplication.delayCall += ShowBatchDialog;
            }
        }

        static void ShowBatchDialog()
        {
            _dialogScheduled = false;
            if (_pendingNewFBX.Count == 0) return;

            var batch = new List<string>(_pendingNewFBX);
            _pendingNewFBX.Clear();

            // Register all immediately — won't appear again regardless of user choice
            ProcessedFBXRegistry.Register(batch);

            FBXBatchDialog.Show(batch);
        }
    }
}