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

namespace GOEventSystem
{
    public class EventSystem_Camera : MonoBehaviour
    {
        Camera rayCamera;
        bool isUsed = true;//事件监测系统是否启用
        bool hoverTriggerEnter;
     
        Transform hoverRecord;//记录当前触发hover的物体
        public float rayDistacne = 800;
        public LayerMask rayGOLayer;

        GOPointerEventData eventData = new GOPointerEventData();
        [Header("Hovr检测的灵敏度，检测时间间隔")]
        public float hoverCheckTime = 0.2f;//射线重复检测时才会触发hover 理论上触发最大时长为hoverCheckTime*2-0.02f；
        float upTime;//一帧运行时间
        float timer;//计时器
        public UnityAction<List<int>> clickOperatorsEvent;
        public UnityAction<List<int>> doubleClickOperatorsEvent;
        public UnityAction clickOutUIEvent;
        // Start is called before the first frame update
        void Start()
        {
            rayGOLayer = ~(1 << -1);
            rayCamera = this.GetComponent<Camera>();
            if (rayCamera == null && Camera.main)
            {
                rayCamera = Camera.main;
            }
           
            if (!rayCamera)
            {
                isUsed = false;
                Debug.Log("无有效检测相机，EventSystem_Camera置位不可用模式");
            }
            upTime = Time.fixedDeltaTime;
            timer = hoverCheckTime;
        }

        /// <summary>
        /// 某些情况下可关闭或再次开启事件检测系统
        /// </summary>
        /// <param name="used"></param>
        public void SetUsed(bool used)
        {
            isUsed = used;
            if (!isUsed && hoverRecord != null&& hoverTriggerEnter)
            {
                hoverRecord.GetComponent<IPointerHoverHandler>().OnHoverExit(eventData);
                hoverRecord = null;
            }
        }

        // Update is called once per frame
        void Update()
        {
            if (!isUsed) return;
            if (EventSystem.current!=null&& EventSystem.current.IsPointerOverGameObject()) return;//UI触发时不做检测
            //HoverCheck();
            ClickCheck();
        }

        void HoverCheck()
        {
            timer-= upTime;
            if (timer > 0) return;
            timer = hoverCheckTime;
            Transform rayHit = CameraRay();
            if (rayHit == null)//没有检测到物体
            {
                if (hoverRecord && hoverTriggerEnter)
                {
                    hoverRecord.GetComponentInParent<IPointerHoverHandler>()?.OnHoverExit(eventData);
                }
                hoverRecord = null;
                hoverTriggerEnter = false;
            }
            else if (rayHit == hoverRecord) //检测到的物体与记录的物体是重复的
            {
                if (hoverTriggerEnter) return;//避免hover重复触发
                hoverTriggerEnter = true;
                rayHit.GetComponentInParent<IPointerHoverHandler>()?.OnHoverEnter(eventData);
            }
            else//检测到其他物体时 
            {
                if (hoverRecord&&hoverTriggerEnter)
                    hoverRecord.GetComponentInParent<IPointerHoverHandler>()?.OnHoverExit(eventData);
                hoverTriggerEnter = false;
                hoverRecord = rayHit;
            }
        }

        private float clickTimer;
        [Header("双击检测的灵敏度，最大触发时间间隔")]
        public float DoubClickTime = 0.2f;//多长时间内再次点击时触发双击
        void ClickCheck()
        {
            if (clickTimer > 0)
            {
                clickTimer -= Time.deltaTime;
            }
            if (Input.GetMouseButtonDown(0) || Input.GetMouseButtonDown(1))
            {
                clickOutUIEvent?.Invoke();//点击地形空白位置
            }
            if (Input.GetMouseButtonDown(0))
            {
                eventData.gOInputButton = GOInputButton.Left;
                if (clickTimer <= 0)
                {
                    Click();
                }
                else
                    DoubleClick();
            }
        }

        List<int> clickOperators = new List<int>();
        void Click()
        {
            clickTimer = DoubClickTime;

            CameraRay()?.GetComponentInParent<IPointerClickHandler>()?.OnPointerClick(eventData);
            //RaycastHit[] raycastHits = CameraRayCastAll();
            //if (raycastHits.Length > 0)
            //{
            //    clickOperators.Clear();
            //    for (int i = 0; i < raycastHits.Length; i++)
            //    {
            //        clickOperators.Add(raycastHits[i].transform.GetComponent<OperatorCtrl>().id);
            //        //Debug.Log("Click Trigger"+ raycastHits[i].transform.name);
            //    }
            //    clickOperatorsEvent?.Invoke(clickOperators);
            //}
        }

        private void DoubleClick()
        {
            CameraRay()?.GetComponentInParent<IPointerDoubleClickHandler>()?.OnPointerDoubleClick(eventData);

            //RaycastHit[] raycastHits = CameraRayCastAll();
            //if (raycastHits.Length > 0)
            //{
            //    clickOperators.Clear();
            //    for (int i = 0; i < raycastHits.Length; i++)
            //    {
            //        clickOperators.Add(raycastHits[i].transform.GetComponent<OperatorCtrl>().id);
            //        //Debug.Log("Click Trigger"+ raycastHits[i].transform.name);
            //    }
            //    doubleClickOperatorsEvent?.Invoke(clickOperators);
            //}
        }

        Ray ray;
        RaycastHit raycastHit;
 
        Transform CameraRay()
        {
            ray = Camera.main.ScreenPointToRay(Input.mousePosition);
            if (Physics.Raycast(ray, out raycastHit, rayDistacne, rayGOLayer))
            {
                return raycastHit.collider.transform;
            }
            else
                return null;
        }



        /// <summary>
        /// 获取射线检测到的所有物体
        /// </summary>
        /// <returns></returns>
        RaycastHit[] CameraRayCastAll()
        {
            ray = Camera.main.ScreenPointToRay(Input.mousePosition);
            return Physics.RaycastAll(ray, rayDistacne, rayGOLayer);
        }
    }
}