OldBlueWater/BlueWater/Assets/02.Scripts/Arrow.cs

using System;
using System.Collections;
using UnityEngine;
using UnityEngine.Pool;

// ReSharper disable once CheckNamespace
namespace BlueWaterProject
{
    public class Arrow : MonoBehaviour
    {
        #region Property and variable

        [Tooltip("발사 이후 자동으로 사라지는데 까지 걸리는 시간")]
        [Range(0f, 10f)]
        [SerializeField] private float autoDestroyTime;

        [Tooltip("화살이 날아가는 속도")]
        [SerializeField] private float arrowSpeed = 15f;

        [SerializeField] private bool isAttacked;
        private float g = Mathf.Abs(Physics.gravity.y);
        private float inaccuracy;
        private Vector3 targetPos;
        private AttackerType attackerType;

        public Coroutine shootCoroutine;
        private Transform attackerTransform;
        private AiStat attackerStat;
        private Rigidbody arrowRigidbody;
        private IObjectPool<Arrow> managedArrowPool;

        #endregion

        #region Unity built-in function

        private void Awake()
        {
            arrowRigidbody = Utils.GetComponentAndAssert<Rigidbody>(transform);
        }

        private void OnDisable()
        {
            if (shootCoroutine == null) return;
            
            StopCoroutine(shootCoroutine);
            shootCoroutine = null;
        }

        private void OnTriggerEnter(Collider other)
        {
            if (other.gameObject.layer == LayerMask.NameToLayer("Ground") ||
                other.gameObject.layer == LayerMask.NameToLayer("Water"))
            {
                DestroyObject();
            }
            else if (other.gameObject.layer == LayerMask.NameToLayer("HitBox"))
            {
                switch (attackerType)
                {
                    case AttackerType.NONE:
                        break;
                    case AttackerType.PLAYER:
                        if (!other.gameObject.CompareTag("Enemy"))
                        {
                            return;
                        }
                        break;
                    case AttackerType.PIRATE:
                        if (!other.gameObject.CompareTag("Enemy"))
                        {
                            return;
                        }
                        break;
                    case AttackerType.ENEMY:
                        if (!other.gameObject.CompareTag("Player") || !other.gameObject.CompareTag("Pirate"))
                        {
                            return;
                        }
                        break;
                    default:
                        throw new ArgumentOutOfRangeException();
                }
                var iDamageable = other.GetComponentInParent<IDamageable>();
                
                iDamageable.TakeDamage(attackerStat, iDamageable.AiStat);
                DestroyObject();
            }
        }

        #endregion
        
        #region Custom function

        public IEnumerator Shoot()
        {
            var time = 0f;
            // 화살의 목표 지점에 대한 불확실성 위치 값
            var inaccuracyOffset = new Vector3
            (
                UnityEngine.Random.Range(-inaccuracy, inaccuracy),
                UnityEngine.Random.Range(-inaccuracy, inaccuracy),
                UnityEngine.Random.Range(-inaccuracy, inaccuracy)
            );
            // 화살의 최종 목표 지점
            var inaccurateTargetPos = targetPos + inaccuracyOffset;
            // 화살 자신의 위치 값
            var myPos = transform.position;
            // 화살이 날아가야 하는 초기 수평 방향
            var toTargetFlat = new Vector3(inaccurateTargetPos.x - myPos.x, 0, inaccurateTargetPos.z - myPos.z);
            // 발사될 때의 화살과 목표 지점 간의 수평 거리
            var horizontalDistance = toTargetFlat.magnitude;
            // 발사될 때의 화살과 목표 지점 간의 수직 거리
            var yOffset = inaccurateTargetPos.y - myPos.y;
            // 화살이 목표 지점에 도착하는 데 예상되는 시간
            var timeToTarget = horizontalDistance / arrowSpeed;
            // 화살의 초기 수직 속도
            var initialVerticalSpeed = (yOffset + (0.5f * g * timeToTarget * timeToTarget)) / timeToTarget;
            // 화살의 발사 속도
            var launchVelocity = toTargetFlat.normalized * arrowSpeed + Vector3.up * initialVerticalSpeed;
            
            arrowRigidbody.velocity = launchVelocity;
            transform.rotation = Quaternion.LookRotation(arrowRigidbody.velocity) * Quaternion.Euler(0f, 90f, 0f);

            while (time < autoDestroyTime)
            {
                time += Time.deltaTime;

                if(arrowRigidbody.velocity != Vector3.zero) 
                {
                    transform.rotation = Quaternion.LookRotation(arrowRigidbody.velocity) * Quaternion.Euler(0f, 90f, 0f);
                }
                yield return null;
            }

            if (gameObject.activeSelf)
            {
                DestroyObject();
            }
        }

        public void ShootArrowCoroutine()
        {
            if (shootCoroutine != null)
            {
                StopCoroutine(shootCoroutine);
                shootCoroutine = null;
            }
            
            shootCoroutine = StartCoroutine(Shoot());
        }

        /// <summary>
        /// 화살이 발사 되기 직전에 필요한 데이터들을 입력받는 함수
        /// </summary>
        public void SetShootingArrow(Vector3 shootPos, Vector3 targetPosition, AiStat attackerAiStat, AttackerType type, float inaccuracyValue)
        {
            transform.position = shootPos;
            targetPos = targetPosition;
            attackerStat = attackerAiStat;
            attackerType = type;
            inaccuracy = inaccuracyValue;
        }

        #endregion
        
        #region ObjectPool function

        private void DestroyObject() => managedArrowPool.Release(this);

        public void SetManagedPool(IObjectPool<Arrow> pool) => managedArrowPool = pool;

        #endregion

        #region Custom function

        /// <summary>
        /// objectPool 시스템에 의해서 Release되는 경우 값을 초기화 시키는 함수
        /// </summary>
        public void ReleaseArrowSetting()
        {
            if (shootCoroutine != null)
            {
                StopCoroutine(shootCoroutine);
                shootCoroutine = null;
            }
            
            arrowRigidbody.velocity = Vector3.zero;
            arrowRigidbody.angularVelocity = Vector3.zero;
            gameObject.SetActive(false);
        }

        #endregion
    }
}