using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;
public class TreasureModelDrag : MonoBehaviour, IBeginDragHandler, IEndDragHandler, IPointerUpHandler, IDragHandler, IPointerClickHandler
{
    Vector2 m_Start;
    bool m_Drag = false;

    public event Action<float> OnValueChange;
    public event Action OnDragComplete;
    public event Action OnDragBegine;

    public void OnBeginDrag(PointerEventData eventData)
    {
        m_Start = eventData.position;
        m_Drag = true;
        if (OnDragBegine != null)
        {
            OnDragBegine();
        }
    }

    public void OnDrag(PointerEventData eventData)
    {
        if (m_Drag)
        {
            var _delta = eventData.position - m_Start;
            m_Start = eventData.position;
            if (OnValueChange != null)
            {
                OnValueChange(_delta.x);
            }
        }
    }

    public void OnEndDrag(PointerEventData eventData)
    {
        if (m_Drag && OnDragComplete != null)
        {
            OnDragComplete();
        }
        m_Drag = false;
    }

    public void OnPointerClick(PointerEventData eventData)
    {
        if (m_Drag)
        {
            return;
        }
        PassEvent(eventData, ExecuteEvents.pointerClickHandler);
    }

    public void OnPointerUp(PointerEventData eventData)
    {
        if (m_Drag && OnDragComplete != null)
        {
            OnDragComplete();
        }
        m_Drag = false;
    }

    void PassEvent<T>(PointerEventData data, ExecuteEvents.EventFunction<T> function) where T : IEventSystemHandler
    {
        List<RaycastResult> results = new List<RaycastResult>();
        EventSystem.current.RaycastAll(data, results);
        GameObject current = data.pointerCurrentRaycast.gameObject;
        for (int i = 0; i < results.Count; i++)
        {
            if (current != results[i].gameObject)
            {
                ExecuteEvents.Execute(results[i].gameObject, data, function);
            }
        }
    }
}