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

public class Enemy : MonoBehaviour {

	private CameraContoller cam;
	private SpriteRenderer sRBase;
	private bool isDead;
	private Vector3 spawnPosition;
	public float maxHealth;
	private float health;
	public int damagePower;
	private GameObject healthBarPos;
	public Texture healthTex;
	public Texture healthTexBack;
	public GameObject healthPickup;

	public bool OnScreen;
	

	// Use this for initialization
	public virtual void Start () {
		cam = Camera.main.gameObject.GetComponent<CameraContoller> ();
		sRBase = GetComponent<SpriteRenderer> ();
		healthBarPos = transform.Find ("HealthBar").gameObject;
		health = maxHealth;
		spawnPosition = transform.position;
		isDead = false;


		OnScreen = false;
	}

	void OnBecameInvisible()
    {
        OnScreen = false;
		
    }

    void OnBecameVisible()
    {
        OnScreen = true;
    }
	
	// Update is called once per frame
	public virtual void Update () {
		if (health <= 0 && !getIsDead()) {
			Die ();
		}

		if (sRBase.color != Color.white) {
			sRBase.color = new Color (sRBase.color.r + 0.04f, 1.0f, 1.0f);
		}
	}

	void OnGUI()
	{
		if (health > 0) {
			Vector2 healthBarVec = Camera.main.WorldToScreenPoint(healthBarPos.transform.position);
			GUI.DrawTexture(new Rect(healthBarVec.x - 30.0f * (1.0f / cam.GetZoom()), Screen.height - healthBarVec.y + 5.0f, 60.0f * (1.0f / cam.GetZoom()), 10.0f * (1.0f / cam.GetZoom())), healthTexBack);
			GUI.DrawTexture(new Rect(healthBarVec.x - 30.0f * (1.0f / cam.GetZoom()), Screen.height - healthBarVec.y + 5.0f, 60.0f * (1.0f / cam.GetZoom()) * ((health / maxHealth)), 10.0f * (1.0f / cam.GetZoom())), healthTex);
		}

	}

	public virtual void Damage (float damageToDo, Vector3 hitPos, float knockback)
	{
		health -= damageToDo;
		sRBase.color = new Color (0.5f, 1.0f, 1.0f);
        Freeze();
	}

	public void SetIsDead(bool newIsDead)
	{
		isDead = newIsDead;
	}

	public bool getIsDead()
	{
		return isDead;
	}

	public virtual void Die()
	{
		sRBase.enabled = false;
		SetIsDead (true);

		int random = Random.Range (0,6);

		if (healthPickup && random % 6 == 0) {
			GameObject health = Instantiate (healthPickup, transform.position, Quaternion.identity);
			HealthPickup pickup = health.GetComponent<HealthPickup> ();
			if (pickup) {
				pickup.SetHealth (10.0f);
			}
		}
	}

	public virtual void Respawn()
	{
		health = maxHealth;
		sRBase.enabled = true;
		SetIsDead (false);
		transform.position = spawnPosition;
	}

    public void Freeze()
    {
        Rigidbody2D rb = GetComponent<Rigidbody2D>();

        if (rb)
        {
            rb.simulated = false;
        }
        StartCoroutine(FreezeTimer());
    }

    public void Unfreeze()
    {
        Rigidbody2D rb = GetComponent<Rigidbody2D>();

        if (rb)
        {
            rb.simulated = true;
        }
    }

	public int GetDamage()
	{
		return damagePower;
	}

    IEnumerator FreezeTimer()
    {
        yield return new WaitForSeconds(0.1f);
        Unfreeze();
    }
}