ChooseDefenderButton

using UnityEngine;
using UnityEngine.UI;
using System.Collections;

public class ChooseDefenderButton : MonoBehaviour {

	public float cooldownLength = 3.0f;
	public bool timerRunning = false;
	public GameObject defenderPrefab;
	public static GameObject selectedDefender;

	private GameObject defenders;
	private float cooldownTimer;


	Transform cover;

	void Awake ()
	{
		if (gameObject.transform.childCount > 0)
		{
			cover = gameObject.transform.GetChild(0);
		}

		defenders = GameObject.Find("Defenders");
	}

	void Start ()
	{
		StartTimer();
	}

	void Update ()
	{
		if (timerRunning) 
		{
			cooldownTimer -= Time.deltaTime;
			UpdateCoverSize();
			
			if (cooldownTimer <= 0)
			{
				timerRunning = false; // then we're done.
			}
		}
	}

	public void SpawnDefender ()
	{
		if (timerRunning) {return;}

		// call all spawners - they only spawn if they're selected. 
		foreach (Transform spawner in defenders.transform)
		{
			spawner.GetComponent<Spawner>().SpawnDefender(defenderPrefab);
		}

		StartTimer();
	}

	
	void UpdateCoverSize ()
	{
		// set the scale based on the ratio of coolDownTimer to coolDownLength.
		if (cooldownTimer > 0) // can't divide by zero
		{
			cover.transform.localScale = new Vector2 (1.0f, cooldownTimer / cooldownLength);
		}
	}

	void StartTimer()
	{
		cooldownTimer = cooldownLength;
		timerRunning = true;
	}
	
}