using System;
using UnityEngine;

public abstract class BulletBase : Entity
{
    [SerializeField] float speed = 10.0f;
    [SerializeField] float lifeTime = 5.0f;

    Vector2 headDirection;
    float elapsedLifeTime = 0.0f;

    public float Speed { get => speed; set => speed = value; }

    public Vector2 HeadDirection
    {
        get
        {
            return Utility.GetDirection2D(transform.eulerAngles.z);
        }
        set
        {
            headDirection = value.normalized;
            transform.eulerAngles = new Vector3(0, 0, Utility.GetAngle2D(headDirection));
        }
    }

    public bool IsFired { get; protected set; } = false;

    public Action<BulletBase> OnBeforeDestroy;
    public Action<Entity> OnEnterCollider;

    private void LateUpdate()
    {
        if (!IsFired) return;

        bool shouldDestroy = !UpdateLifeTime();
        shouldDestroy |= !UpdateBullet(Time.fixedDeltaTime);

        if (shouldDestroy)
        {
            OnBeforeDestroy?.Invoke(this);
            Destroy(gameObject);
        }
    }

    private bool UpdateLifeTime()
    {
        elapsedLifeTime += Time.fixedDeltaTime;
        return elapsedLifeTime < lifeTime;
    }

    protected abstract bool UpdateBullet(float deltaTime);

    public virtual void Fire(Transform target = null, bool resetLifeTime = true)
    {
        if (target != null)
            HeadDirection = target.position - transform.position;

        if(resetLifeTime)
            elapsedLifeTime = 0;

        IsFired = true;
    }
}