using System.Collections;
using System.Collections.Generic;
using UnityEngine;

[System.Serializable]
public class DamagedTarget
{
    public GameObject target;
    public float damageTime;

    public DamagedTarget( GameObject g,  float t)
    {
        damageTime = t;
        target = g;
    }
}

public class CollisionDamage : MonoBehaviour
{

    // 1 for player, 2 for enemies
    public int target;


    public enum eos { None, Enter, Stay };
    public eos enterOrStay = eos.None;

    public Entity parentEntity;
    public Stats myStats = new Stats();

    public Damage.type type = Damage.type.Physical;
    public Damage.lifeDamage lifeDamage = Damage.lifeDamage.Normal;


    private float delay = 0;
    public float maxDelay = 0.5f;

    /*
     *  Okay, so this works like a list saying who this unit damaged in the past (maxDelay) seconds.
     *  If an object is here, then it means it was damaged in the past (maxDelay) seconds... theorically.
     * */
    public List<DamagedTarget> recentlyDamagedTargets = new List<DamagedTarget>();


    private void LateUpdate()
    {
        foreach (DamagedTarget i in recentlyDamagedTargets)
        {
            // This lessens every delay every update until it goes slightly past zero.
            if (i.damageTime > 0)
                i.damageTime -= Time.deltaTime;


            // Not using "else" here because the value changes within the first condition.
            // This is where the error resides. I don't know why, since the only other place that uses this list is on collision, and this condition
            // checks if the gameObject has already been destroyed. You can't colide with null, theorically. ;/
            if (i.damageTime <= 0 && i.target == null)
                recentlyDamagedTargets.Remove(i);

        }
    }

    private void Start()
    {
        if (parentEntity != null) myStats = parentEntity.myStats;
    }

    void OnTriggerEnter2D(Collider2D col)
    {
        if (enterOrStay == eos.Enter)
        {

            Entity d = null;
            if (target == 1 && col.gameObject.tag == "Player")
            {
                d = col.gameObject.GetComponent(typeof(PlayerController)) as PlayerController;
            }

            if (target == 2 && col.gameObject.tag == "Enemy")
            {
                d = col.gameObject.GetComponent(typeof(Enemy)) as Enemy;
            }

            if (d != null)
            {

                Damage dmg = new Damage(myStats.baseDamage, type, lifeDamage);
                dmg.myCritChance = myStats.critcalChance;
                dmg.myCritMultiplier = myStats.criticalMultiplier;

                int index = recentlyDamagedTargets.FindIndex(r => r.target == col.gameObject);
                if (index < 0) {
                    recentlyDamagedTargets.Add(new DamagedTarget(col.gameObject, maxDelay));
                    d.Damage(dmg);
                }

                else
                {
                    if (recentlyDamagedTargets[index].damageTime <= 0)
                    {
                        recentlyDamagedTargets[index].damageTime = maxDelay;
                        d.Damage(dmg);
                    }
                }


            }

        }

    }

    // There's a OnCollisionStay under here, but I'll cut it for simplicity, since it isn't even being called for now
}