using System.Collections;
using System.Collections.Generic;
using System.Linq;
using UnityEngine;
using UnityEngine.SceneManagement;


namespace Stary.Evo.FiniteStateMachine
{
    public static class FSMInitialize
    {
        /// <summary>
        /// 状态机初始化
        /// </summary>
        /// <param name="targetScene">指定场景</param>
        /// <returns></returns>
        public static FSMManager Init(Scene targetScene)
        {
            GameObject targetObject = targetScene.GetRootGameObjects().FirstOrDefault(go => go.name == "FSMManger");
            FSMManager fSMManager;

            if (targetObject == null)
            {
                targetObject = new GameObject("FSMManger");
                SceneManager.MoveGameObjectToScene(targetObject, targetScene);

                fSMManager = new FSMManager();
                fSMManager.FSMMangerObject = targetObject;

                void OnSceneUnloaded(Scene scene)
                {
                    // 当场景卸载时释放缓存
                    if (scene.name == targetScene.name)
                    {
                        GameObject.Destroy(targetObject);
                        fSMManager = null;
                    }
                }
                SceneManager.sceneUnloaded += OnSceneUnloaded;

                return fSMManager;
            }
            else
            {
                Debug.LogError("场景: " + targetScene.name + "已经初始化过FSM状态机！！！");
                return null;
            }
        }
    }
}