using System;
using DG.Tweening;
using UnityEngine;
using Utils;

namespace Ui.Screens
{
	[RequireComponent(typeof(RectTransform))]
	public class ScreenContainer : MonoBehaviour
	{
		private static ScreenContainer _instance;

		public static ScreenContainer Instance
		{
			get { return _instance; }
		}

		[SerializeField] private ScreenSelector _selector;
		[SerializeField] private RectTransform _container;
		[SerializeField] private int _rectWidth;
		[SerializeField] private float _threshold;
		[SerializeField] private int _leftScreens;
		[SerializeField] private int _rightScreens;
		private bool _dragStart;
		private static bool _hold;
		public static bool Hold
		{
			get { return _hold; }
			set
			{
				_hold = value;
                if (_hold)
                    Debug.Log("Hold true!");
                else
                    Debug.Log("Hold false!");
            }
		}
		private int _scene;
		
		private float _position;
		private float _containerPosition;
		private float _currentPosition;

		private float ContainerPosition
		{
			get { return _containerPosition; }
			set
			{
				var targetValue = value < 0 && value < -_leftScreens * _rectWidth ? -_leftScreens * _rectWidth :
					value > 0 && value > _rightScreens * _rectWidth ? _rightScreens * _rectWidth : value;
				_container.SetRight(-targetValue);
				_container.SetLeft(targetValue);
				_containerPosition = targetValue;
			}
		}

		private void Awake()
		{
			_instance = this;
		}

		private void OnDisable()
		{
			_hold = false;
		}

		public static event Action<bool> DragEvent;

		private void Drag()
		{
            if (GlobalsVar.gBoard.DialogsCount > 0)
                return;

			if (_dragStart) return;
			_dragStart = true;
			_position = Input.mousePosition.x;
		}

		private void Update()
		{
            if (GlobalsVar.gSkipClickTime > 0f)
            {
                if (_dragStart)
                    _dragStart = false;

                return;
            }

			if (_hold)
			{
				if (_dragStart)
				{
                    GlobalsVar.gOnMenuDrag = true;
					SetNewPosition();
				}
				return;
			}

			if (Input.GetMouseButton(0))
			{
				Drag();
			}

			if (!_dragStart)
				return;

			if (!Input.GetMouseButton(0))
			{
				SetNewPosition();
				return;
			}

			ChangeDragPosition();
		}

		private void SetNewPosition()
		{
			_dragStart = false;
			var targetScene = Input.mousePosition.x - _position < -(_threshold * Screen.width) ? _scene - 1 :
				Input.mousePosition.x - _position > (_threshold * Screen.width) ? _scene + 1 : _scene;
			SetNewPosition(targetScene);
		}

		public void SetNewPosition(int scene)
		{
			_scene = scene > _rightScreens ? _rightScreens : scene < -_leftScreens ? -_leftScreens : scene;
			_hold = true;
            Debug.Log("Hold true!");
			_currentPosition = _rectWidth * _scene;
			DOTween.To(() => ContainerPosition, x => ContainerPosition = x, _rectWidth * _scene, 0.5f).OnComplete(() =>
				{
                    GlobalsVar.gOnMenuDrag = false;
                    _hold = false;
                    Debug.Log("Hold false!");
                    _dragEvent = false;
					if (DragEvent != null)
						DragEvent(false);
				});

			if (_selector != null)
				_selector.SetButton(_scene + 2);
		}

		private bool _dragEvent;

		private void ChangeDragPosition()
		{
			var currentPoint = _currentPosition + (Input.mousePosition.x - _position) * (_rectWidth / (float)Screen.width);
			if (Mathf.Abs(Input.mousePosition.x - _position) > 0.05 * Screen.width && !_dragEvent)
			{
				_dragEvent = true;
				if (DragEvent != null)
					DragEvent(true);
			}
			ContainerPosition = currentPoint;
		}
		
		private void OnValidate()
		{
			if (_container == null)
				_container = gameObject.GetComponent<RectTransform>();
		}
	}
}