using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using System.Text;


/// <summary>
/// 教学提示UI控制
/// </summary>
public class LearningUIController : MonoBehaviour
{
    private static LearningUIController _instance;
    public static LearningUIController Instance
    {
        get
        {
            if (_instance == null)
            {
                Debug.Log("未实例化LearningUIController");
            }
            return _instance;
        }
    }

    public Canvas _canvas;
    public Image _frameImg;//边框
    public Image _backImg;//背景
    public Text _showText;//提示框
    private StringBuilder _stringBuilder = new StringBuilder();
    private string _stringInfo;
    public RectTransform _maskRectTrans;//遮罩层

    public Vector2 _closeSize;
    public Vector2 _openSize;
    public Vector2 _maskCloseSize;
    public Vector2 _maskOpenSize;

    public float _moveTime = 1;
    private float _moveSpeed;
    private float _maskMoveSpeed;
    private RectTransform _frameRectTrans;

    private bool _open = false;
    private bool _moving = false;
    private bool _textShowing = false;
    private char[] _textChar;
    private int _currentTextCount;

    public delegate void UIEvent();

    public UIEvent OpenFinished;
    public UIEvent CloseFinished;


    private void Awake()
    {
        _instance = this;
    }
    // Use this for initialization
    void Start()
    {
        _frameRectTrans = _frameImg.GetComponent<RectTransform>();
        _moveSpeed = Vector3.Distance(_openSize, _closeSize) / _moveTime;
        _maskMoveSpeed = Vector3.Distance(_maskOpenSize, _maskCloseSize) / _moveTime;

        Init();
    }

    // Update is called once per frame
    void Update()
    {
        UIMoving();
        ShowText();

        if (Input.GetKeyDown(KeyCode.Space))
        {
            SetLearnText("测试参数设置", !_open);
        }
    }


    public void Init()
    {
        _frameRectTrans.sizeDelta = _closeSize;
        _maskRectTrans.sizeDelta = _maskCloseSize;
        _open = true;
    }

    public void SetLearningState(bool state)
    {
        if (!_open)
        {
            _canvas.gameObject.SetActive(true);
        }
        _open = state;
        _moving = true;
    }
    public void SetLearnText(string text, bool state)
    {
        if (!_open)
        {
            _canvas.gameObject.SetActive(true);
        }

        SetText(text);
        _open = state;
        _moving = true;
    }

    /// <summary>
    /// 边框控制
    /// </summary>
    public void UIMoving()
    {
        if (!_moving) return;

        _frameRectTrans.sizeDelta = Vector2.MoveTowards(_frameRectTrans.sizeDelta,
            _open ? _openSize : _closeSize, _moveSpeed * Time.deltaTime);
        _maskRectTrans.sizeDelta = Vector2.MoveTowards(_maskRectTrans.sizeDelta,
    _open ? _maskOpenSize : _maskCloseSize, _maskMoveSpeed * Time.deltaTime);

        if (_frameRectTrans.sizeDelta == (_open ? _openSize : _closeSize))
        {
            _moving = false;

            _canvas.gameObject.SetActive(_open);

            if (!_open && CloseFinished != null)
            {
                CloseFinished();
            }
            else if (_open && OpenFinished != null)
            {
                OpenFinished();
            }
        }
    }

    /// <summary>
    /// 设置显示文本
    /// </summary>
    /// <param name="text"></param>
    public void SetText(string text)
    {
        if (text == _stringInfo) return;
        _stringInfo = text;
        _textShowing = true;
        _stringBuilder = new StringBuilder();
        _textChar = _stringInfo.ToCharArray();
        _currentTextCount = 0;
    }

    void ShowText()
    {
        if (!_textShowing) return;

        _stringBuilder.Append(_textChar[_currentTextCount]);
        _showText.text = _stringBuilder.ToString();
        _currentTextCount++;

        if (_currentTextCount == (_textChar.Length))
        {
            _textShowing = false;
        }
    }
}