using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEditor;

namespace TweenAnimation
{
    public class PlaybackTimer
    {
        // 动画
        private TweenAnimation m_Animation;

        // 考虑了Pause的playback逻辑时间，考虑了playbackLimit
        public float time
        {
            get
            {
                float t = realTime;
                if (m_PauseRealTime != -1)
                    t = m_PauseRealTime - m_StartRealTime;
                t = m_Animation.ApplyLimit(t);
                return t;
            }
        }

        // 从调用Resume开始后的时间
        private float realTime
        {
            get
            {
                return (float)EditorApplication.timeSinceStartup - m_StartRealTime;
            }
        }

        private float m_StartRealTime;

        private float m_PauseRealTime;

        public PlaybackTimer(TweenAnimation animation)
        {
            m_Animation = animation;
            Reset();
        }

        //Start & Resume
        public void Resume()
        {
            if (m_PauseRealTime != -1)
                m_StartRealTime = (float)EditorApplication.timeSinceStartup - time;
            else
                m_StartRealTime = (float)EditorApplication.timeSinceStartup;
            m_PauseRealTime = -1;
        }

        public void Pause()
        {
            m_PauseRealTime = (float)EditorApplication.timeSinceStartup;
            float t = m_Animation.ApplyLimit(m_PauseRealTime - m_StartRealTime);
            m_PauseRealTime = m_StartRealTime + t;
        }

        public void Stop()
        {
            Reset();
        }

        public void Reset()
        {
            m_StartRealTime = -1;
            m_PauseRealTime = -1;
        }

        public void SetPauseTimeOffset(float dt)
        {
            m_PauseRealTime += dt;
        }

    }
}