using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System.Linq;
using Cysharp.Threading.Tasks;
using UnityEngine.Jobs;
using UnityEngine.Pool;
namespace BITKit.Sensors
{
    public class RangeSensor : Sensor
    {
        [Header(Constant.Header.Settings)]
        public float radius;
        public int fov;
        public bool requireSight;
        public bool autoUpdate;
        [Header(Constant.Header.Settings)]
        public LayerMask blockLayer;
        [Header(Constant.Header.InternalVariables)]
        FrameUpdate frameUpdater;
        Collider[] colliders = new Collider[32];
        RaycastHit[] hits;
        Collider currentCollider;
        Location location;
        int length;
        Vector3 dir;
        float maxDistance;
        public override IEnumerable<Transform> Get() => detecteds;

        private void Update()
        {
            if (autoUpdate)
            {
                Execute().Forget();
            }
        }
        public override UniTask Execute()
        {
            if (frameUpdater)
            {
                if (maxDistance is 0)
                {
                    maxDistance = Mathf.Max(subSensors.Select(x => x.GetDistance()).Append(radius).ToArray());
                }
                location.position = transform.position;
                location.rotation = transform.rotation;
                var list = ListPool<Transform>.Get();
                for (int i = 0; i < Physics.OverlapSphereNonAlloc(location, maxDistance, colliders, detectLayer); i++)
                {
                    currentCollider = colliders[i];
                    if (IsValid(currentCollider))
                        list.Add(currentCollider.transform);
                    else
                    {
                        foreach (var sensor in subSensors)
                        {
                            if (sensor.IsValid(currentCollider))
                            {
                                list.Add(currentCollider.transform);
                                break;
                            }
                        }
                    }
                }
                detecteds = list.ToArray();
                list.Clear();
                ListPool<Transform>.Release(list);
            }
            return UniTask.CompletedTask;
        }
        public override bool IsValid(Collider collider)
        {
            if (ignoreColliders.Contains(collider)
                || CheckFov(ref collider) is false
                || CheckSight(ref collider) is false
                || CheckDistance(ref collider) is false
            )
            {
                return false;
            }
            else return true;
        }
        public override float GetDistance() => radius;
        bool CheckFov(ref Collider collider)
        {
            if (fov is not 0)
            {
                var _dir = collider.transform.position - transform.position;
                if (_dir.sqrMagnitude > 0)
                {
                    var dir = Quaternion.LookRotation(_dir);
                    if (Vector3.Dot(transform.forward, _dir) > 0 && fov > Quaternion.Angle(transform.rotation, dir))
                    {
                        return true;
                    }
                    else return false;
                }
                else return true;
            }
            else
            {
                return true;
            }
        }
        bool CheckSight(ref Collider collider)
        {
            if (requireSight)
            {
                length = Physics.RaycastNonAlloc(
                    location.position,
                     collider.transform.position - location,
                     hits,
                     Vector3.Distance(location, collider.transform.position),
                     blockLayer
                     );
                if (length > 0)
                {
                    if (hits[0].collider == collider)
                    {
                        return true;
                    }
                }
                else return true;
            }
            return false;
        }
        bool CheckDistance(ref Collider collider)
        {
            return Vector3.Distance(collider.transform.position, transform.position) <= radius;
        }
    }
    #if UNITY_EDITOR
   
    #endif
}