namespace Plugins.CxShine.UIUtil
{
    using UnityEngine;
    using UnityEngine.UI;
    using UnityEngine.EventSystems;

    [RequireComponent(typeof(ScrollRect))]
    public class ScrollRectPassThroughComp : MonoBehaviour, IPointerDownHandler, IPointerUpHandler
    {
        private ScrollRect scrollRect;
        private bool isPointerDown = false;

        private void Awake()
        {
            // 添加GraphicRaycaster组件
            gameObject.AddComponent<GraphicRaycaster>();

            // 添加EventSystem组件
            if (FindObjectOfType<EventSystem>() == null)
            {
                GameObject eventSystem = new GameObject("EventSystem");
                eventSystem.AddComponent<EventSystem>();
                eventSystem.AddComponent<StandaloneInputModule>();
            }

            scrollRect = GetComponent<ScrollRect>();
        }

        public void OnPointerDown(PointerEventData eventData)
        {
            isPointerDown = true;
            CheckPassThrough(eventData);
        }

        public void OnPointerUp(PointerEventData eventData)
        {
            isPointerDown = false;
        }

        private void CheckPassThrough(PointerEventData eventData)
        {
            if (isPointerDown)
            {
                // 计算指针位置和ScrollRect的相对位置
                Vector2 localPoint;
                RectTransformUtility.ScreenPointToLocalPointInRectangle(scrollRect.content, eventData.position, eventData.pressEventCamera, out localPoint);

                // 如果指针在ScrollRect的范围内，则透传事件
                if (scrollRect.content.rect.Contains(localPoint))
                {
                    eventData.pointerPressRaycast = eventData.pointerCurrentRaycast;
                }
            }
        }
    }

}