using System;
using System.Collections;
using Cielonos.Core.UI;
using Cielonos.MainGame.Characters;
using Cielonos.MainGame.Map;
using DG.Tweening;
using SLSUtilities.General;
using UnityEngine;
using UnityEngine.SceneManagement;

namespace Cielonos.MainGame
{
    public partial class MapManager : Singleton<MapManager>
    {
        public MapBaseCollection baseCollection;

        public ZoneData currentZoneData;
        public ZoneManager currentZoneManager;

        /// <summary>
        /// 加载指定 ZoneData 对应的场景，完成后回调 onComplete。
        /// 首次加载时跳过淡出（画面已是黑屏），后续切换时先淡出再卸载旧场景。
        /// </summary>
        /// <param name="nextZoneData">目标 Zone 数据。</param>
        /// <param name="onComplete">场景完全就绪后的回调。</param>
        /// <param name="skipBattleSetup">
        /// 为 true 时跳过敌人生成和 CombatRoomSm.StartRoom()，
        /// 用于重入已完成的战斗节点（只需重新加载场景环境，无需重新开始战斗）。
        /// </param>
        public void LoadZone(ZoneData nextZoneData, Action onComplete = null, bool skipBattleSetup = false)
        {
            StartCoroutine(SwitchRoomRoutine(nextZoneData, onComplete, skipBattleSetup));
        }
    }

    public partial class MapManager
    {
        public static MapBaseCollection BaseCollection => Instance.baseCollection;
    }

    public partial class MapManager
    {
        private IEnumerator SwitchRoomRoutine(ZoneData nextZoneData, Action onComplete, bool skipBattleSetup = false)
        {
            bool isFirstLoad = currentZoneData == null;

            // 0. 禁用玩家输入，防止切换期间误操作
            PlayerInputSubcontroller playerInput = MainGameManager.Player.inputSc;
            playerInput.inputActions.Player.Disable();

            // MODIFIED: 在开始异步加载前禁用 CharacterController 并重置下落重力速度，防止加载期间自由落体掉入虚空
            if (MainGameManager.Player.collisionSc != null && MainGameManager.Player.collisionSc.useCharacterController)
            {
                MainGameManager.Player.collisionSc.characterController.enabled = false;
            }
            if (MainGameManager.Player.movementSc != null)
            {
                MainGameManager.Player.movementSc.gravitationalMovement = Vector3.zero;
                MainGameManager.Player.movementSc.jumpVelocity = 0f;
            }

            // 1. 淡出画面（首次加载时画面已经是黑屏，无需再 FadeToBlack）
            if (!isFirstLoad)
            {
                bool fadeOutComplete = false;
                ScreenFader.Instance.FadeToBlack(onComplete: () => fadeOutComplete = true).Play();
                yield return new WaitUntil(() => fadeOutComplete);
            }

            // 2. 异步卸载旧场景
            if (!isFirstLoad)
            {
                yield return SceneManager.UnloadSceneAsync(currentZoneData.sceneName);
            }

            currentZoneData = nextZoneData;

            // 3. 异步加载新场景（Additive）
            string nextSceneName = nextZoneData.sceneName;
            AsyncOperation op = SceneManager.LoadSceneAsync(nextSceneName, LoadSceneMode.Additive);
            op.allowSceneActivation = false;

            while (op.progress < 0.9f)
            {
                yield return null;
            }

            op.allowSceneActivation = true;
            yield return op;

            // 4. 设为活跃场景
            Scene nextScene = SceneManager.GetSceneByName(nextSceneName);
            SceneManager.SetActiveScene(nextScene);

            yield return new WaitForEndOfFrame();

            // 5. 重置战斗状态、初始化 Zone
            CombatManager.AttackAreaSm.Reset();
            CombatManager.CombatRoomSm.Reset();

            // 6. 将玩家放置到 playerSpawns 指定的出生点（无论是否跳过战斗均需执行）
            SpawnPlayerAtZone(nextZoneData);

            if (skipBattleSetup)
            {
                // 已完成节点：仅生成交互物体（ExitGate 等），跳过敌人生成和战斗启动
                ZoneManager.instance.SetupZoneWithoutEnemies(currentZoneData);
            }
            else
            {
                ZoneManager.instance.SetupZone(currentZoneData);

                // 等待一帧，让所有 Instantiate 出的敌人执行 Start()，
                // 将自身 Add 进 activeEnemiesList，再启动战斗房间判定。
                yield return null;
                CombatManager.CombatRoomSm.StartRoom();
            }

            // 7. 淡入画面
            yield return new WaitForSeconds(0.5f);
            ScreenFader.Instance?.FadeToClear().Play();

            // 8. 恢复玩家输入
            playerInput.inputActions.Player.Enable();

            // 9. 回调通知调用方（RunManager）
            onComplete?.Invoke();
        }

        /// <summary>
        /// 将玩家传送到 ZoneData.playerSpawns 中随机选择的出生点。
        /// 若无配置则回退到原点。
        /// </summary>
        private void SpawnPlayerAtZone(ZoneData zoneData)
        {
            Transform playerTransform = MainGameManager.Player.transform;

            // MODIFIED: 传送前必须禁用 CharacterController，否则位置设置可能会被物理系统忽略
            if (MainGameManager.Player.collisionSc != null && MainGameManager.Player.collisionSc.useCharacterController)
            {
                MainGameManager.Player.collisionSc.characterController.enabled = false;
            }

            Vector3 targetPosition = Vector3.zero;
            Quaternion targetRotation = Quaternion.identity;
            bool foundSpawn = false;

            if (zoneData.playerSpawns != null && zoneData.playerSpawns.Count > 0)
            {
                // 多个出生点时随机选择一个
                ZoneData.SpawnPointKey spawnKey = zoneData.playerSpawns.Count == 1
                    ? zoneData.playerSpawns[0]
                    : zoneData.playerSpawns[UnityEngine.Random.Range(0, zoneData.playerSpawns.Count)];

                if (ZoneManager.instance.spawnPoints.TryGetValue(spawnKey.group, out var points)
                    && spawnKey.index < points.Count)
                {
                    SpawnPoint point = points[spawnKey.index];
                    point.GetTransform(out targetPosition, out targetRotation);
                    foundSpawn = true;
                    Debug.Log($"[MapManager] 玩家放置在出生点 {spawnKey.group}_{spawnKey.index}。");
                }
            }

            if (!foundSpawn)
            {
                Debug.LogWarning("[MapManager] ZoneData 未配置 playerSpawns 或出生点不存在，玩家将放置在原点。");
            }

            playerTransform.position = targetPosition;
            playerTransform.rotation = targetRotation;

            // MODIFIED: 彻底重置重力、跳跃等缓存速度，避免传送后向下冲破地板
            ResetPlayerMovementVelocity();

            // MODIFIED: 传送及重置速度完成后，重新启用 CharacterController
            if (MainGameManager.Player.collisionSc != null && MainGameManager.Player.collisionSc.useCharacterController)
            {
                MainGameManager.Player.collisionSc.characterController.enabled = true;
            }
        }

        // MODIFIED: 新增清空玩家移动控制状态的方法，确保重力、跳跃速度全部归零
        private void ResetPlayerMovementVelocity()
        {
            var movementSc = MainGameManager.Player.movementSc;
            if (movementSc != null)
            {
                movementSc.gravitationalMovement = Vector3.zero;
                movementSc.jumpVelocity = 0f;
                movementSc.horizontalMovement = Vector3.zero;
                movementSc.verticalMovement = Vector3.zero;
                movementSc.finalMovementVelocity = Vector3.zero;
                movementSc.jumpMovement = Vector3.zero;
                movementSc.movementModifier = Vector3.zero;
            }
        }
    }
}