//--------------------------------------------------------
//    [Author]:           第二世界
//    [  Date ]:           Monday, April 09, 2018
//--------------------------------------------------------
using UnityEngine;
using System.Collections;
using UnityEngine.UI;

namespace Snxxz.UI
{
    [RequireComponent(typeof(RectTransform))]
    public class UILinerMove : MonoBehaviour
    {
        [SerializeField] float m_Duration;
        public float duration {
            get { return m_Duration; }
            set { m_Duration = value; }
        }

        [SerializeField] Vector2 m_From;
        public Vector2 from {
            get { return m_From; }
            set { m_From = value; }
        }

        [SerializeField] Vector2 m_To;
        public Vector2 to {
            get { return m_To; }
            set { m_To = value; }
        }

        float timer = float.MaxValue;
        RectTransform rectTransform { get { return this.transform as RectTransform; } }

        public void Begin()
        {
            if (duration < 0f)
            {
                return;
            }

            if (!this.gameObject.activeInHierarchy)
            {
                Stop();
            }
            else
            {
                timer = 0f;
                rectTransform.anchoredPosition = from;
            }
        }

        public void Stop()
        {
            timer = float.MaxValue;
            rectTransform.anchoredPosition = to;
        }

        private void OnDisable()
        {
            if (timer < duration)
            {
                Stop();
            }
        }

        private void LateUpdate()
        {
            if (timer < duration)
            {
                timer += Time.deltaTime;
                var t = Mathf.Clamp01(timer / duration);
                rectTransform.anchoredPosition = Vector2.Lerp(from, to, t);
            }
        }

    }

}