using System.Collections.Generic;
using TH1_Renderer.UnitAtomAnim;
using UnityEngine;

namespace TH1_Anim.UnitAtomAnim
{


    public class UnitAnimManager
    {
        // Start is called before the first frame update
        
        private Queue<IUnitAtomAnim> _animQueue = new Queue<IUnitAtomAnim>();
        private bool _isBusy;
        private IUnitAtomAnim _currentAnim;

        public UnitAnimManager()
        {
        }
        
        public void Init()
        {
            // 在这里可以进行资源加载、UI逻辑类的实例化等操作
            // 例如：
            // _wonderCompletedUI = new WonderCompletedAnnouncementUI(...);
            
            //Debug.Log("PresentationManager 已初始化。");
        }

        public void EnqueueAnim(UnitAtomAnimType type,IUnitAtomAnimData data)
        {
            var anim = UnitAtomAnimFactory.Create(type,data);
            if (anim == null)
            {
                Debug.LogError("试图添加一个空的动画！");
                return;
            }

            _animQueue.Enqueue(anim);
            
            // 尝试执行下一个任务
            TryProcessNext();
        }
        
        private void TryProcessNext()
        {
            // 如果当前正在忙，
            
            if (_isBusy)return;

            //队列为空，则不执行
            if (_animQueue.Count == 0)
            {
                _currentAnim = null;
                return;
            }
            
            // 标记为忙碌状态
            _isBusy = true;
            
            // 从队列中取出下一个任务
            _currentAnim = _animQueue.Dequeue();
            
        }
        
        private void OnAnimCompleted()
        {
            // 解除忙碌状态
            _isBusy = false;
            
            // 立即尝试处理队列中的下一个任务
            TryProcessNext();
        }
        
        public void Update(UnitMono unitMono)
        {
            //Step #1 如果没有动画要播放，return
            if (_currentAnim == null) return;
            
            switch (_currentAnim.State)
            {
                case UnitAtomAnimState.Wrong:
                    _isBusy = false;
                    TryProcessNext();
                    break;
                case UnitAtomAnimState.Finished:
                    OnAnimCompleted();
                    break;
                case UnitAtomAnimState.Prepare:
                    if (!_currentAnim.OnStart(unitMono))
                    {
                        _currentAnim.State = UnitAtomAnimState.Wrong;
                        break;
                    }
                    //Debug.Log($"Prepare -> Playing {Time.time}");
                    _currentAnim.StartTime = Time.time;
                    _currentAnim.State = UnitAtomAnimState.Playing;
                    break;
                case UnitAtomAnimState.Playing:
                    _currentAnim.OnUpdate(unitMono,Time.time - _currentAnim.StartTime);
                    if (Time.time >= _currentAnim.StartTime + _currentAnim.Duration)
                    {
                        _currentAnim.OnFinished(unitMono);
                        _currentAnim.State = UnitAtomAnimState.Finished;
                    }
                    break;
            } 
        }
        
    }
    
}