using UnityEngine;
using System.Collections;

public class GameManager : MonoBehaviour 
{
	public static GameManager Instance;
	public Transform[] spaceShipPrefebs;

	public Transform explosionEffect;

	public static string HERO_NAME = "Player";
	public static string ENEMY_NAME = "Enemy";
	public static string ALLY_NAME = "Ally";

	void Awake()
	{
		Instance = this;

		int heroShipType = 0;
		if (GlobalObject.Instance) {
			heroShipType = GlobalObject.Instance.shipType;
		} else {
			Debug.LogError("GlobalObject.Instance is NULL!");
		}

		CreateHero(spaceShipPrefebs[heroShipType]);
	}

	public static Transform CreateHero(Transform template)
	{
		Transform tp = Instantiate(template, Vector3.zero, Quaternion.identity) as Transform;
		//tp.tag = HERO_NAME;

		return tp;
	}

	public static Transform CreateEnemy(Transform template)
	{
		Transform tp = Instantiate(template, Vector3.zero, Quaternion.identity) as Transform;
		// Defined in prefabs
		// tp.tag = ENEMY_NAME;
		
		return tp;
	}

	public static Transform CreateAlly(Transform template)
	{
		Transform tp = Instantiate(template, Vector3.zero, Quaternion.identity) as Transform;
		// Defined in prefabs
		// tp.tag = ALLY_NAME;
		
		return tp;
	}

	public static Transform GetHero()
	{
		GameObject heroGameObject = GameObject.FindGameObjectWithTag(HERO_NAME);
		if (heroGameObject != null) {
			return heroGameObject.transform;
		}
		return null;
	}

	public static GameObject GetClosestEnemy(Transform observer)
	{
		GameObject[] enemies = GameObject.FindGameObjectsWithTag(ENEMY_NAME);

		GameObject closest = null;
		float bestScore = Mathf.Infinity;

		foreach(GameObject enemy in enemies) 
		{
			Vector3 relativePosition = enemy.transform.position - observer.transform.position;
			float distance = relativePosition.magnitude;
			relativePosition.Normalize();

			// -1 0 +1 -> 3 2 1
			float penalty = (2.0f - Vector3.Dot(observer.transform.forward, relativePosition)) / 3.0f;
			float score = distance * penalty * penalty * penalty;

			if (score < bestScore) {
				bestScore = score;
				closest = enemy;
			}
		}
		/*
		if (closest) 
		{
			Debug.Log("Found: " + closest.transform.position.ToString());
		} else {
			Debug.Log("Nothing FOUND!!");
		}*/
		return closest;
	}

	void Start()
	{

	}
	
	// Update is called once per frame
	void Update () 
	{
		if (Input.GetKey (KeyCode.Escape))					
		{
			Application.Quit();
		}

		if (Input.GetKey (KeyCode.Z))
		{
			CommunicationCenter.Instance.ShowSmallCamera1(true);
		}
	}
}