using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Events;
using UnityEngine.EventSystems;

namespace JCUnityLib.UI
{
    public class ValidateJigsawDragBar : MonoBehaviour, IDragHandler, IEndDragHandler, IBeginDragHandler
    {
        RectTransform _self;
        RectTransform _parent;
        float _minX { get => 0; }
        float _maxX { get => _parent.rect.width - _self.rect.width; }
        bool _draged;
        float _value;
        public UnityAction<float> onDrag;
        public UnityAction<float> onEndDrag;

        void Awake()
        {
            _self = transform as RectTransform;
            _parent = transform.parent as RectTransform;
        }

        void Update()
        {
            if (!_draged && _self.anchoredPosition.x > 0)
            {
                _self.anchoredPosition += Vector2.left * 2000 * Time.deltaTime;
                if (_self.anchoredPosition.x < 0) _self.anchoredPosition = Vector3.zero;
                UpdateValue();
                onDrag?.Invoke(_value);
            }
        }

        void UpdateValue()
        {
            _value = _self.anchoredPosition.x / (_maxX - _minX);
        }

        void MoveSelf(Vector3 v3)
        {
            v3.y = 0;
            _self.Translate(v3, Space.Self);
            
            if (_self.anchoredPosition.x > _maxX) 
            {
                v3.x = _maxX;
                _self.anchoredPosition = v3;
            }
            else if (_self.anchoredPosition.x < 0) 
            {
                v3.x = _minX;
                _self.anchoredPosition = v3;
            }
        }

        public void OnDrag(PointerEventData eventData)
        {
            MoveSelf(eventData.delta);
            UpdateValue();
            onDrag?.Invoke(_value);
        }

        public void OnEndDrag(PointerEventData eventData)
        {
            _draged = false;
            onEndDrag?.Invoke(_value);
        }

        public void OnBeginDrag(PointerEventData eventData)
        {
            _draged = true;
        }
    }
}