using Pausable;
using UnityEngine;
using UnityEngine.Events;

namespace AI
{
    public class ShootingEnemyAI : MonoBehaviour, IPausable
    {
        [SerializeField] protected float attacksPerSecond = 1f;
        [SerializeField] protected float attackRange = 5f;
        [SerializeField] protected float timeForProjectileToHit = .25f;

        protected float cooldownPerShoot = 0f;
        protected float remainingCooldown = 0f;

        private float attackRangeSquared = 5f;
        private Transform target = null;

        private bool canShoot => (target.transform.position - transform.position).sqrMagnitude < attackRangeSquared && target != null;

        public UnityEvent OnShoot { get; protected set; } = null;

        #region IPausable
        public bool IsPaused { get; protected set; } = false;
        public virtual void Pause() => IsPaused = true;
        public virtual void Resume() => IsPaused = false;
        #endregion

        protected void Awake()
        {
            cooldownPerShoot = 1f / attacksPerSecond;
            attackRangeSquared = attackRange * attackRange;
            OnShoot = new UnityEvent();
            UpdateTarget(FindObjectOfType<Player.PlayerController>()?.transform);
        }

        protected void Update()
        {
            remainingCooldown -= Time.deltaTime;

            if (remainingCooldown <= 0f && canShoot)
                Shoot();
        }

        protected void Shoot()
        {

            Projectile projectile = ProjectilePool.Instance.Get();
            projectile.transform.position = transform.position;

            Vector3 velocity = GetVelocityForProjectile(timeForProjectileToHit);

            RaycastHit2D raycastHit2D = Physics2D.Raycast(transform.position, target.position - transform.position, attackRange);
            if (raycastHit2D.transform != target)
                velocity = GetVelocityForProjectile(timeForProjectileToHit * 2);

            projectile.SetVelocity(velocity);

            remainingCooldown = cooldownPerShoot;
            OnShoot?.Invoke();
        }

        private Vector3 GetVelocityForProjectile(float time)
        {
            Vector3 vector3 = target.position - transform.position;
            vector3.z = 0f;
            vector3.y -= (Physics2D.gravity.y / 2) * (time * time);
            vector3 /= time;
            return vector3;
        }

        public void UpdateTarget(Transform transform) => target = transform;

        private void OnDrawGizmosSelected()
        {
            Gizmos.color = Color.yellow;
            Gizmos.DrawWireSphere(transform.position, 0.125f);
            Gizmos.color = Color.red;
            Gizmos.DrawWireSphere(transform.position, attackRange);
        }
    }
}