using System.Collections;
using System.Collections.Generic;
using Module.Log;
using UnityEngine;
using UnityEngine.UI;

public class RollNum : MonoBehaviour
{
    // 需配置部分
    public float maxSpeed;      // 转动最大速度
    public float deltaSpeed;    // 加速度
    public float height;        // 10个数字的总长度（一周高度）
    public float childHeight;   // 每个数字高度
    // ----------

    private float curSpeed;             // 当前速度
    private RectTransform rt;           // 当前物体Rt组件，控制位移
    private float deltaSlowSpeed;       // 减速加速度
    private float roundLenght;          // 转动一圈的路程
    private float totalLength;          // 总路程
    private float tempLength;           // 补足长度
    private int des;                    // 需要的转动结果

    public delegate void voidNoneDel();
    public event voidNoneDel FinishEvent;       // 展示结束事件

    private void OnEnable()
    {
        // 归位
        rt = transform as RectTransform;
        rt.anchoredPosition = new Vector2(rt.anchoredPosition.x, 0.0f);
        roundLenght = 10 * childHeight;
        curSpeed = 0.0f;
    }

    private void Update()
    {
        rt.anchoredPosition += Vector2.up * curSpeed * Time.deltaTime;

        if (rt.anchoredPosition.y > height)
        {
            float newBegin = rt.anchoredPosition.y - height;
            rt.anchoredPosition = new Vector2(rt.anchoredPosition.x, newBegin);
        }
    }

    public void SetAndBegin(int des)
    {
        if(des >= 0 && des <= 9)
        {
            this.des = des;
            StopAllCoroutines();
            StartCoroutine("SpeedUp");
        }
        else
        {
            LogModule.ErrorLog("Des is wrong, please reset it");
        }
    }

    private IEnumerator SpeedUp()
    {
        curSpeed = 0.0f;
        while (true)
        {
            curSpeed += Time.deltaTime * deltaSpeed;
            if (curSpeed > maxSpeed)
            {
                curSpeed = maxSpeed;
                BeginSlow();
                yield break;
            }

            yield return null;
        }
    }

    private void BeginSlow()
    {
        StopAllCoroutines();

        if(des < 0 || des > 9)
        {
            return;
        }

        if (des * childHeight >= rt.anchoredPosition.y)
        {
            tempLength = des * childHeight - rt.anchoredPosition.y;
        }
        else
        {
            tempLength = des * childHeight + roundLenght - rt.anchoredPosition.y;
        }

        totalLength = tempLength + 3 * roundLenght;

        StartCoroutine("SlowDown");
    }

    private IEnumerator SlowDown()
    {
        yield return 0;

        deltaSlowSpeed = maxSpeed * maxSpeed / (2.0f * totalLength);
        while (true)
        {
            curSpeed -= deltaSlowSpeed * Time.deltaTime;
            if (curSpeed < 0.0f)
            {
                curSpeed = 0.0f;

                if(FinishEvent != null)
                {
                    FinishEvent.Invoke();
                }

                yield break;
            }

            yield return null;
        }
    }

    //// 结束后的修正过程
    //private IEnumerator FinallyCorrect()
    //{
        
    //}
}