using UnityEngine;
using System.Collections;

public class Missile : MonoBehaviour 
{
	public Transform impactEffect;
	public Transform explosionEffect;
	public Transform head;

	private GameObject target;
	private float _timer = 0;

	private int autoDestructionCountDown = 5;
	private float _speed = 350;

	private static float ROTATION_SPEED = 1.0f;

	private float hitPower = 100000;
	//private bool isActive = false;

	private Transform firedBy;

	// "Fired By" Reference to ignore collision detection for the ship that fired the laser
	public void SetFiredBy(Transform who) {
		firedBy = who;
	}

	void Update()
	{
		//(isActive==false)return;

		_timer -= Time.deltaTime;
		if (_timer < 0.0f) 
		{
			_timer += 1.0f;
			autoDestructionCountDown--;
			if (autoDestructionCountDown<0) 
			{
				Instantiate(impactEffect, transform.position, transform.rotation);
				Destroy(gameObject);
				return;
			}
			Debug.Log ("Re-evaluating target");
			target = GameManager.GetClosestEnemy(this.transform);
		}

		
		if (target!=null) 
		{
			//transform.LookAt(target);

			float step = ROTATION_SPEED * Time.deltaTime;

			Vector3 targetDir = target.transform.position - this.transform.position;
			targetDir.Normalize();

			Vector3 newDir = Vector3.RotateTowards (this.transform.forward, targetDir, step, 0.0f);
			this.transform.rotation = Quaternion.LookRotation (newDir);

			Debug.DrawLine(this.transform.position, target.transform.position, Color.cyan);
		}

		Vector3 _direction = transform.forward*_speed*Time.deltaTime;
		float _distance = _direction.magnitude;

		Vector3 startPosition = transform.position;
		// advance
		transform.position += _direction;

		if(_distance>0)
		{
			RaycastHit _hit;
			if (Physics.Raycast(startPosition, _direction, out _hit, _distance*5)) 
			{
				Debug.Log("raycast: " + _hit.transform.gameObject.tag);
				if (_hit.transform != firedBy && !_hit.collider.isTrigger) 
				{	

					Quaternion _rotation = Quaternion.FromToRotation(Vector3.up, _hit.normal);
					Instantiate(impactEffect, _hit.point, _rotation);

					GameManager.HandleWeaponHit(_hit, hitPower, firedBy, explosionEffect, _rotation);

					Destroy(gameObject);
				}
			}
		}
	}
}