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
{
    /// <summary>
    /// Zone 加载后的初始化模式。
    /// EnvironmentOnly 用于回到已完成节点或起点等非战斗场景，只恢复场景和交互物；
    /// CombatEncounter 用于正式进入战斗节点，会生成敌人并启动 CombatRoomSubmodule。
    /// </summary>
    public enum ZoneSetupMode
    {
        EnvironmentOnly,
        CombatEncounter,
    }

    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。保留 bool 参数是为了兼容旧调用点；
        /// 新代码优先使用 ZoneSetupMode 重载，让调用语义更清晰。
        /// </summary>
        public void LoadZone(ZoneData nextZoneData, Action onComplete = null, bool skipBattleSetup = false)
        {
            ZoneSetupMode setupMode = skipBattleSetup
                ? ZoneSetupMode.EnvironmentOnly
                : ZoneSetupMode.CombatEncounter;
            LoadZone(nextZoneData, onComplete, setupMode);
        }

        /// <summary>
        /// 使用明确的初始化模式加载 Zone，并在场景、出生点、战斗初始化全部完成后回调调用方。
        /// </summary>
        public void LoadZone(ZoneData nextZoneData, Action onComplete, ZoneSetupMode setupMode)
        {
            StartCoroutine(SwitchRoomRoutine(nextZoneData, onComplete, setupMode));
        }
    }

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

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

            // 切换场景期间禁止玩家输入，避免玩家在卸载/加载窗口里触发移动或攻击。
            PlayerInputSubcontroller playerInput = MainGameManager.Player.inputSc;
            playerInput.inputActions.Player.Disable();

            // 加载前禁用 CharacterController，并清空下落速度，避免玩家在异步加载期间掉入虚空。
            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;
            }

            // 首次进入时画面本来就是黑屏；后续切换需要先淡出再卸载旧场景。
            if (!isFirstLoad)
            {
                bool fadeOutComplete = false;
                ScreenFader.Instance.FadeToBlack(onComplete: () => fadeOutComplete = true).Play();
                yield return new WaitUntil(() => fadeOutComplete);
            }

            if (!isFirstLoad)
            {
                yield return SceneManager.UnloadSceneAsync(currentZoneData.sceneName);
            }

            currentZoneData = nextZoneData;

            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;

            Scene nextScene = SceneManager.GetSceneByName(nextSceneName);
            SceneManager.SetActiveScene(nextScene);

            yield return new WaitForEndOfFrame();

            // 每次切换 Zone 都先清理上一场战斗遭遇的运行时缓存。
            CombatManager.ResetCurrentEncounter();

            // 出生点放置独立于战斗模式：回到已完成节点时也需要正确传送玩家。
            SpawnPlayerAtZone(nextZoneData);

            if (setupMode == ZoneSetupMode.EnvironmentOnly)
            {
                // 已完成节点或非战斗入口：只生成 ExitGate 等交互物，不生成敌人，也不启动房间结算。
                ZoneManager.instance.SetupZoneWithoutEnemies(currentZoneData);
            }
            else
            {
                ZoneManager.instance.SetupZone(currentZoneData);

                // 等待一帧，让 Instantiate 出的敌人完成 Start() 并注册到 EnemySubmodule。
                yield return null;
                CombatManager.CombatRoomSm.StartRoom();
            }

            yield return new WaitForSeconds(0.5f);
            ScreenFader.Instance?.FadeToClear().Play();

            playerInput.inputActions.Player.Enable();
            onComplete?.Invoke();
        }

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

            // CharacterController 启用时直接设置 Transform 可能被物理状态覆盖，所以传送前先禁用。
            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)
            {
                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;

            ResetPlayerMovementVelocity();

            if (MainGameManager.Player.collisionSc != null && MainGameManager.Player.collisionSc.useCharacterController)
            {
                MainGameManager.Player.collisionSc.characterController.enabled = true;
            }
        }

        /// <summary>
        /// 清空玩家移动控制器里的速度缓存，避免传送后继承上一帧的重力、跳跃或水平位移。
        /// </summary>
        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;
            }
        }
    }
}