using UnityEngine;
using TMPro;

namespace Elbyss.Optimization
{
    public class PerformanceHUD : MonoBehaviour
    {
        private float deltaTime = 0.0f;
        private string displayFormat = "{0:0.0} ms ({1:0.} fps)";

        private void Update()
        {
            deltaTime += (Time.unscaledDeltaTime - deltaTime) * 0.1f;
        }

        private void OnGUI()
        {
            int w = Screen.width, h = Screen.height;

            GUIStyle style = new GUIStyle();

            Rect rect = new Rect(10, 10, w, h * 2 / 100);
            style.alignment = TextAnchor.UpperLeft;
            style.fontSize = h * 2 / 50;
            style.normal.textColor = new Color(0.0f, 1.0f, 0.5f, 1.0f);
            
            float msec = deltaTime * 1000.0f;
            float fps = 1.0f / deltaTime;
            string text = string.Format(displayFormat, msec, fps);
            
            GUI.Label(rect, text, style);
        }
    }
}