#define ANIM_CROSS_FADE
using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
#if UNITY_EDITOR
using UnityEditor;
#endif

// 单独一层动画
public class AnimatorLayerInfo
{
    public int layer;

    public int layerIndex { get { return (int)layer; } }

    public string name { get { return m_Animator.GetLayerName(layerIndex); } }

    private Animator m_Animator;

    // 当前动作的animation data，如果是blendtree选第一个动作
    private AnimationData m_AnimationData;
    public AnimationData animationData
    {
        get
        {
            if (clipInfo == null || clipInfo.Length == 0)
                return null;
            var clip = clipInfo[0]; //选第一个
            string folder = m_UnitAnimation.owner.folder;
            string name = clip.clip.name;
            if (m_AnimationData != null && m_AnimationData.animationName == name)
                return m_AnimationData;
            string path = folder + "AnimationData/" + name + ".asset" ; // 要注意这里使用名字区别的，因为最终每个角色的动画都会在一个目录下面
#if UNITY_EDITOR
            m_AnimationData  = AssetDatabase.LoadAssetAtPath<AnimationData>(path);
#endif
            return m_AnimationData;
        }
    }

	// 当前动作所有animation data，包括blendtree使用的所有动画
	//private List<AnimationData> m_AnimationDatas;
	//public List<AnimationData> animationDatas
	//{
	//    get
	//    {
	//        return null;
	//    }
	//}
	 
	// 当前在播放的动作
	// 如果处于transition中，动作不变，切换完成后才会到下一个动作
	public AnimatorStateInfo stateInfo
    {
        get
        {
			AnimatorStateInfo stateInfo = m_Animator.GetCurrentAnimatorStateInfo(layerIndex);
			if (isInTransition)
			{
				stateInfo = m_Animator.GetNextAnimatorStateInfo(layerIndex);
			}
		//	Debug.Assert(stateInfo.IsName(layerName + "." + m_CurrentState));
			return stateInfo;
		}
    }

    private int preStateHash = -1;

    // 当前正在播放和融合的片段信息
    public AnimatorClipInfo[] clipInfo
    {
        get
        {
            AnimatorClipInfo[]  clips = m_Animator.GetCurrentAnimatorClipInfo(layerIndex);
            if(clips.Length == 0)
            {
                // 如果transition设置了打断，会出现GetCurrentAnimatorClipinfo返回空数组的情况
                clips = m_Animator.GetNextAnimatorClipInfo(layerIndex);
            }
            return clips;
        }
    }

    public int stateHash
    {
        get
        {
            return stateInfo.shortNameHash;
        }
    }

    //public float playbackTimeInSeconds
    //{
    //    get
    //    {
    //        return stateInfo.normalizedTime * stateInfo.length;// stateInfo.length会等于infinity，因为设置了animator.speed = 0 
    //    }
    //}
    
    // 并非准确的播放时间，只是逻辑时间，因为动画会加速减速
    public float playbackTimeInSeconds
    {
        get
        {
            return playbackNormalizedTime * clipInfo[0].clip.length; 
        }
    }

    // 这个是真实世界的时间
    private float m_PlaybackRealTime;
    public float playbackRealTimeInSeconds
    {
        get
        {
            return m_PlaybackRealTime;
        }
    }

    // 播放进度百分比，[0-1]，是逻辑上的，如果动画不是loop，那么播放完后normalizedTime是1
    public float playbackNormalizedTime
    {
        get
        {
            //return stateInfo.normalizedTime % 1f;
            if (!stateInfo.loop && stateInfo.normalizedTime > 1)
                return 1;
            return stateInfo.normalizedTime % 1f;
        }
    }

	public float playbackSpeed
	{
		get
		{
			return m_Animator.GetFloat("PlaybackSpeed" + layerIndex);
		}
		set
		{
			float v = Mathf.Clamp(value, 0, 10);
			m_Animator.SetFloat("PlaybackSpeed" + layerIndex, v);
		}
	}

	public float weight
    {
        get
        {
            return m_Animator.GetLayerWeight(layerIndex);
        }
    }

    public int nextStateHash
    {
        get
        {
            //if (!isInTransition)
            //    return 0;
            AnimatorStateInfo nextState = m_Animator.GetNextAnimatorStateInfo(layerIndex);
            int hash = nextState.shortNameHash; // 如果不在过渡中，hash是0
            return hash;
        }
    }

    public bool isInTransition
    {
        get
        {
            return m_Animator.IsInTransition(layerIndex);
        }
    }

	public bool applySpeedCurve { get; set; }

	UnitAnimation m_UnitAnimation;

    Coroutine m_CalcPlaybackTimeCoroutine;

	TimelineEventProxy m_TimelineEventProxy;

	public string m_CurrentState;

	public readonly string layerName;

	public AnimatorLayerInfo(UnitAnimation unitAnimation, Animator animator, int layer, string layerName)
    {
		this.layerName = layerName;
        this.m_UnitAnimation = unitAnimation;
        this.m_Animator = animator;
        this.layer = layer;
		m_CalcPlaybackTimeCoroutine = unitAnimation.StartCoroutine(CalcPlaybackRealTimeCoroutine());
		m_TimelineEventProxy = new TimelineEventProxy(unitAnimation.owner.transform, unitAnimation.owner);
		applySpeedCurve = true;
	}

	IEnumerator CalcPlaybackRealTimeCoroutine()
    {
        while (true)
        {
            if(preStateHash != stateHash)
            {
                m_PlaybackRealTime = 0;
            }
            m_PlaybackRealTime += Time.deltaTime;
            preStateHash = stateHash;
            yield return null; 
        }
    }

    public bool IsToggleOpen(EAnimationToogle toggle)
    {
        if (m_AnimationData == null)
            return false;
        return m_AnimationData.IsToggleOpen(toggle, playbackNormalizedTime);
    }

	public void OnUpdate()
	{
        // 执行事件
        m_TimelineEventProxy.ExecuteAnimationEvents(animationData, playbackTimeInSeconds * TimelineEventProxy.FPS);

        // 播放速度控制
        if (applySpeedCurve && animationData != null && animationData.speedCurve != null)
		{
			playbackSpeed = animationData.speedCurve.Evaluate(playbackNormalizedTime);
		}
	}

	public void OnCrossFade(string animState, float normalizedTransitionDuration, float normalizedTimeOffset, float normalizedTransitionTime )
	{
		m_CurrentState = animState; 
		m_Animator.CrossFade(animState.ToString(), normalizedTransitionDuration, layerIndex, normalizedTimeOffset, normalizedTransitionTime);
	}

	public void OnPlay(string animState, float normalizedTime)
	{
		m_CurrentState = animState;
		m_Animator.Play(animState, layerIndex, normalizedTime);
	}

}

// 控制动画播放、执行动作timeline(包括执行事件和碰撞盒)
// 每个layer同时只会有一个动画在播放，在执行transition时，current animation依然是
// 这个动作，只有完全过渡完成后才会切到下一个动作
// 当前是什么动作以ainmator的GetCurrentAnimatorStateInfo为准
[DisallowMultipleComponent]
public class UnitAnimation : UnitComponent
{
    public AnimatorLayerInfo[] layers { get { return m_LayerInfo; } }
    protected AnimatorLayerInfo[] m_LayerInfo;

    public Animator animator { get { return m_Animator; } }
    protected Animator m_Animator;


    public bool isInTransition
    {
        get
        {
            return m_Animator.IsInTransition(0);
        }
    }

}