Detecting / facing target

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

#if UNITY_EDITOR
using UnityEditor;
#endif

public class EnemyAI : MonoBehaviour {

    public float visualDetectionRadius;
    public float audioDetectionRadius;
    public float peripheral;

    public float turnSpeed = 1f;
    public float speed = 1f;

    // Use this for initialization
    void Start () {
	}

	// Update is called once per frame
	void Update ()
    {
        SpotTarget();

        HearTarget();

    }

    void SpotTarget()
    {
        Collider[] colliders = Physics.OverlapSphere(transform.position, visualDetectionRadius);

        foreach (Collider collider in colliders)
        {
            // check if target is player
            if (collider.CompareTag("Player"))
            {
                //transform.rotation = Quaternion.LookRotation(Vector3.RotateTowards(transform.forward, collider.transform.position, turnSpeed, 0f));
                //turn towards the player
                float playerDirection = transform.position.AngleToFaceTarget(collider.transform.position);

                float myFacing = transform.eulerAngles.y;

                if (Mathf.DeltaAngle(myFacing, playerDirection) <= peripheral)
                {
                    RaycastHit hit;
                    if (Physics.Raycast(transform.position, transform.forward, out hit)
                    && hit.transform.CompareTag("Player"))
                    {
                        Charge();
                    }
                    LookAtTarget(collider.transform);


                    // checking if object exists in front of us && object is tagged player


                }
            }
        }
    }

    void HearTarget()
    {
        Collider[] colliders = Physics.OverlapSphere(transform.position, audioDetectionRadius);

        foreach (Collider collider in colliders)
        {
            // check if target is player
            if (collider.CompareTag("Player"))
            {
                LookAtTarget(collider.transform);
            }
        }
    }

    void LookAtTarget(Transform target)
    {
        //transform.rotation = Quaternion.LookRotation(Vector3.RotateTowards(transform.forward, collider.transform.position, turnSpeed, 0f));
        //turn towards the player
        float angleToTurn = transform.position.AngleToFaceTarget(target.position);


        Quaternion newRotation = Quaternion.Euler(0, angleToTurn, 0);
        transform.rotation = Quaternion.RotateTowards(transform.rotation, newRotation, 120f * Time.deltaTime);
    }

    private void Charge()
    {

            // moving forward 1m / second
            transform.position += transform.forward * speed* Time.deltaTime;
    }

#if UNITY_EDITOR
    void OnDrawGizmos()
    {
        Gizmos.color = Color.black;
        Gizmos.DrawWireSphere(transform.position, visualDetectionRadius);
        Gizmos.color = Color.red;
        Gizmos.DrawWireSphere(transform.position, audioDetectionRadius);

        //Vector3 leftPeripheralTarget = transform.rot(Vector3.forward * visualDetectionRadius).
        //Gizmos.DrawRay(transform.position, ()
    }
#endif
}