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

#if UNITY_EDITOR
using UnityEditor;
#endif
[Serializable] public class UnityEventTranfromAndInt : UnityEvent<Transform, int> { }
[Serializable] public class UnityEventTranformArray : UnityEvent<Transform[]> { }
[Serializable] public class UnityEventTranform : UnityEvent<Transform> { }

public class Alertness : MonoBehaviour {

    public int alertRadius;
    public int attackRadius;
    [Range(0, 360)] public float attackAngle;

#if UNITY_EDITOR
    public Color alertColor = Color.blue;
    public Color attackColor = Color.red;
#endif

    private float angle;
    private float distance;
    private Vector3 from;
    private float forwardAttackAngle;
    private Transform tr;
    private List<Transform> targets = new List<Transform>();
    
    public UnityEventTranform onEnterAttackRadiusEvent =new UnityEventTranform();
    public UnityEventTranformArray onTargetEnterEvent = new UnityEventTranformArray();
    public UnityEventTranfromAndInt onTargetExitEvent = new UnityEventTranfromAndInt();
    
    private void Awake()
    {
        tr = transform;
        forwardAttackAngle = attackAngle / 2;

        var collider = GetComponent<SphereCollider>();
        if (collider == null)
        {
            collider = gameObject.AddComponent<SphereCollider>();
        }
        collider.center = Vector3.zero;
        collider.isTrigger = true;
        collider.radius = alertRadius;
    }

    private void Update()
    {
        foreach (var target in targets)
        {
            distance = Vector3.Distance(tr.position, target.position);
            from = target.position - tr.position;
            angle = Vector3.Angle(from, tr.forward);
            if (distance <= attackRadius && angle <= forwardAttackAngle)
            {
                onEnterAttackRadiusEvent.Invoke(target);
            }
        }
    }

    private void OnTriggerEnter(Collider other)
    {
        targets.Add(other.transform);
        onTargetEnterEvent.Invoke(targets.ToArray());
    }

    private void OnTriggerExit(Collider other)
    {
        targets.Remove(other.transform);
        onTargetExitEvent.Invoke(other.transform, targets.Count);
    }

#if UNITY_EDITOR
    private void OnDrawGizmos()
    {
        var color = Handles.color;
        Handles.color = alertColor;
        Handles.DrawWireDisc(transform.position, transform.up, alertRadius);

        Handles.color = attackColor;
        var StartLine = Quaternion.Euler(0, -attackAngle / 2, 0) * this.transform.forward;
        Handles.DrawSolidArc(this.transform.position, this.transform.up, StartLine, attackAngle, attackRadius);
        Handles.color = color;
    }
#endif

}