using UnityEngine;
using System.Collections;

public class HUDFPS : MonoBehaviour
{
	private static HUDFPS instance;

	public static HUDFPS Instance { get { return instance; } }
// Attach this to a GUIText to make a frames/second indicator.
//
// It calculates frames/second over each updateInterval,
// so the display does not keep changing wildly.
//
// It is also fairly accurate at very low FPS counts (<10).
// We do this not by simply counting frames per interval, but
// by accumulating FPS for each frame. This way we end up with
// correct overall FPS even if the interval renders something like
// 5.5 frames.
 
	public  float updateInterval = 0.5F;
	private float accum = 0; // FPS accumulated over the interval
	private int   frames = 0; // Frames drawn over the interval
	private float timeleft; // Left time for current interval
	
	public float fps;

	void Start()
	{
		instance = this;
		if (!GetComponent<GUIText>())
		{
			AVDebug.Log("UtilityFramesPerSecond needs a GUIText component!");
			enabled = false;
			return;
		}
		timeleft = updateInterval;  
	}
 
	void Update()
	{
		timeleft -= Time.deltaTime;
		accum += Time.timeScale / Time.deltaTime;
		++frames;
    
		// Interval ended - update GUI text and start new interval
		if (timeleft <= 0.0)
		{
			// display two fractional digits (f2 format)
			fps = accum / frames;
			string format = System.String.Format("{0:F2} FPS", fps);
			GetComponent<GUIText>().text = format;

			if (fps < 30)
			{
				GetComponent<GUIText>().material.color = Color.yellow;
			}
			else
			if (fps < 10)
			{
				GetComponent<GUIText>().material.color = Color.red;
			}
			else
			{
				GetComponent<GUIText>().material.color = Color.green;
			}
			//  DebugConsole.Log(format,level);
			timeleft = updateInterval;
			accum = 0.0F;
			frames = 0;
		}
	}
}