using System.Collections.Generic;
using System.Linq;
using UnityEditor;
using UnityEngine;
using UnityEngine.Playables;
using UnityEngine.Timeline;

namespace Streamingle.Editor
{
	public class TimelineBindingTransferWindow : EditorWindow
	{
		private PlayableDirector sourceDirector;
		private PlayableDirector targetDirector;
		private bool matchByHierarchyPath = true;
		private bool requireSameTrackType = true;
		private bool showPreview = true;
		private Vector2 scroll;

		private struct TrackMap
		{
			public TrackAsset sourceTrack;
			public TrackAsset targetTrack;
			public Object boundObject;
		}

		private List<TrackMap> previewMappings = new List<TrackMap>();

		[MenuItem("Tools/Timeline Tools/Transfer Bindings")]
		public static void ShowWindow()
		{
			GetWindow<TimelineBindingTransferWindow>("Timeline Binding Transfer");
		}

		private void OnGUI()
		{
			EditorGUILayout.LabelField("타임라인 바인딩 복사", EditorStyles.boldLabel);
			EditorGUILayout.Space();

			sourceDirector = (PlayableDirector)EditorGUILayout.ObjectField("소스 디렉터", sourceDirector, typeof(PlayableDirector), true);
			targetDirector = (PlayableDirector)EditorGUILayout.ObjectField("타겟 디렉터", targetDirector, typeof(PlayableDirector), true);

			EditorGUILayout.Space();
			matchByHierarchyPath = EditorGUILayout.ToggleLeft("트랙 계층 경로로 매칭 (권장)", matchByHierarchyPath);
			requireSameTrackType = EditorGUILayout.ToggleLeft("트랙 타입이 동일할 때만 매칭", requireSameTrackType);
			showPreview = EditorGUILayout.ToggleLeft("미리보기 표시", showPreview);

			EditorGUILayout.Space();
			EditorGUI.BeginDisabledGroup(!CanBuildMapping());
			if (GUILayout.Button("매핑 미리보기 갱신"))
			{
				BuildPreviewMapping();
			}
			EditorGUI.EndDisabledGroup();

			EditorGUI.BeginDisabledGroup(previewMappings.Count == 0);
			if (GUILayout.Button("바인딩 복사 실행"))
			{
				ApplyMappings();
			}
			EditorGUI.EndDisabledGroup();

			if (showPreview)
			{
				DrawPreview();
			}
		}

		private bool CanBuildMapping()
		{
			if (sourceDirector == null || targetDirector == null) return false;
			var srcAsset = sourceDirector.playableAsset as TimelineAsset;
			var dstAsset = targetDirector.playableAsset as TimelineAsset;
			return srcAsset != null && dstAsset != null;
		}

		private void BuildPreviewMapping()
		{
			previewMappings.Clear();

			var srcAsset = sourceDirector.playableAsset as TimelineAsset;
			var dstAsset = targetDirector.playableAsset as TimelineAsset;
			if (srcAsset == null || dstAsset == null)
			{
				EditorUtility.DisplayDialog("오류", "소스/타겟 디렉터에 유효한 TimelineAsset이 필요합니다.", "확인");
				return;
			}

			var sourceTracks = GetAllOutputTracks(srcAsset).ToList();
			var targetTracks = GetAllOutputTracks(dstAsset).ToList();

			// 타겟 트랙 인덱스 구성
			Dictionary<string, List<TrackAsset>> nameToTargetTracks = new Dictionary<string, List<TrackAsset>>();
			Dictionary<string, TrackAsset> pathToTargetTrack = new Dictionary<string, TrackAsset>();

			foreach (var t in targetTracks)
			{
				string nameKey = t.name;
				if (!nameToTargetTracks.TryGetValue(nameKey, out var list))
				{
					list = new List<TrackAsset>();
					nameToTargetTracks[nameKey] = list;
				}
				list.Add(t);

				string pathKey = GetTrackPath(t);
				if (!pathToTargetTrack.ContainsKey(pathKey)) pathToTargetTrack.Add(pathKey, t);
			}

			foreach (var s in sourceTracks)
			{
				var bound = sourceDirector.GetGenericBinding(s);
				if (bound == null) continue;

				TrackAsset matched = null;
				if (matchByHierarchyPath)
				{
					pathToTargetTrack.TryGetValue(GetTrackPath(s), out matched);
				}
				else
				{
					if (nameToTargetTracks.TryGetValue(s.name, out var candidates))
					{
						if (requireSameTrackType)
						{
							matched = candidates.FirstOrDefault(c => c.GetType() == s.GetType());
						}
						else
						{
							matched = candidates.FirstOrDefault();
						}
					}
				}

				if (matched == null) continue;
				if (requireSameTrackType && matched.GetType() != s.GetType()) continue;

				previewMappings.Add(new TrackMap
				{
					sourceTrack = s,
					targetTrack = matched,
					boundObject = bound as Object
				});
			}
		}

		private void ApplyMappings()
		{
			if (targetDirector == null)
			{
				EditorUtility.DisplayDialog("오류", "타겟 디렉터가 필요합니다.", "확인");
				return;
			}

			int applied = 0;
			Undo.RecordObject(targetDirector, "Timeline Binding Transfer");
			foreach (var map in previewMappings)
			{
				if (map.targetTrack == null || map.boundObject == null) continue;
				targetDirector.SetGenericBinding(map.targetTrack, map.boundObject);
				applied++;
			}

			EditorUtility.SetDirty(targetDirector);
			var go = targetDirector.gameObject;
			if (go != null && go.scene.IsValid())
			{
				UnityEditor.SceneManagement.EditorSceneManager.MarkSceneDirty(go.scene);
			}

			EditorUtility.DisplayDialog("완료", $"바인딩 복사 완료: {applied}개 적용", "확인");
		}

		private void DrawPreview()
		{
			EditorGUILayout.Space();
			EditorGUILayout.LabelField("매핑 미리보기", EditorStyles.boldLabel);
			scroll = EditorGUILayout.BeginScrollView(scroll, GUILayout.MinHeight(150));

			if (previewMappings.Count == 0)
			{
				EditorGUILayout.HelpBox("미리보기가 비어 있습니다. '매핑 미리보기 갱신'을 눌러 생성하세요.", MessageType.Info);
			}
			else
			{
				foreach (var m in previewMappings)
				{
					EditorGUILayout.BeginVertical("box");
					EditorGUILayout.LabelField($"소스: {GetTrackDisplay(m.sourceTrack)}");
					EditorGUILayout.LabelField($"타겟: {GetTrackDisplay(m.targetTrack)}");
					EditorGUILayout.ObjectField("바인딩 객체", m.boundObject, typeof(Object), true);
					EditorGUILayout.EndVertical();
				}
			}

			EditorGUILayout.EndScrollView();
		}

		private static IEnumerable<TrackAsset> GetAllOutputTracks(TimelineAsset asset)
		{
			// GetOutputTracks는 서브트랙을 평탄화하여 반환하므로 그대로 사용
			return asset.GetOutputTracks();
		}

		private static string GetTrackPath(TrackAsset track)
		{
			// 상위 트랙 이름을 포함한 경로 문자열 생성
			List<string> names = new List<string>();
			var current = track;
			while (current != null)
			{
				names.Add(current.name);
				current = current.parent as TrackAsset;
			}
			names.Reverse();
			return string.Join("/", names);
		}

		private static string GetTrackDisplay(TrackAsset track)
		{
			if (track == null) return "(없음)";
			return $"{GetTrackPath(track)}  <{track.GetType().Name}>";
		}
	}
}