// by chai
using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

namespace TweenAnimation
{
    [Serializable]
    public abstract class TweenModule 
    {
        public bool enabled = true;

        public float timeOffset = 0;

        public float duration;

        private float m_LastTime;

#if UNITY_EDITOR
        public virtual string name { get { return ""; } }

        public string description;

        public virtual string tooltip { get { return "Tween Module " + name; } }

        [NonSerialized]
        public bool unfold;
#endif

        private bool IsValidTime0(float time0)
        {
            return time0 >= 0 && time0 <= duration;
        }

        // 根据当前时间更新值, time的范围是tween animation的duration
        public void OnUpdate(float time)
        {
            float time0 = time - timeOffset;
            if (!IsValidTime0(time0) && !IsValidTime0(duration))
                return;
            m_LastTime = time0;
            SetValue(Mathf.Clamp(time0, 0, duration)); 
        }

        // time是去掉了offset后的时间
        protected abstract void SetValue(float time);

    }
}