modules/project/SPT.Custom/Utils/BundleUtils.cs

using UnityEngine;

namespace SPT.Custom.Utils
{
    public class BundleUtils : MonoBehaviour
    {
        private GameObject rootObject;
        private int current;
        private int maximum;
        private string bundleName;
        private Texture2D bgTexture;
        private bool started;
        private GUIStyle labelStyle;
        private GUIStyle windowStyle;
        private Rect windowRect;

        public static BundleUtils Create()
        {
            GameObject bundleUtilsObject = new GameObject("BundleUtilsObject");
            BundleUtils bundleUtils = bundleUtilsObject.AddComponent<BundleUtils>();
            bundleUtils.rootObject = bundleUtilsObject;
            bundleUtils.current = 0;
            bundleUtils.maximum = 0;
            bundleUtils.enabled = true;
            bundleUtils.bgTexture = new Texture2D(2, 2);
            bundleUtils.windowRect = bundleUtils.CreateRectangle(500, 80);
            return bundleUtils;
        }

        public void Init(int length)
        {
            maximum = length;
        }

        public void SetProgress(int progress, string fileName)
        {
            current = progress;
            bundleName = fileName;
        }

        public void Dispose()
        {
            Destroy(rootObject);
            Destroy(this);
        }

        public void OnGUI()
        {
            if (!started)
            {
                CreateStyles();
            }

            GUI.backgroundColor = Color.black;
            GUI.Window(0, windowRect, DrawWindow, "Bundle Loading", windowStyle);
        }

        private void CreateStyles()
        {
            labelStyle = new GUIStyle(GUI.skin.label)
            {
                alignment = TextAnchor.MiddleCenter
            };

            windowStyle = new GUIStyle(GUI.skin.window)
            {
                alignment = TextAnchor.UpperCenter
            };
            windowStyle.normal.background = bgTexture;

            started = true;
        }

        private Rect CreateRectangle(int width, int height)
        {
            return new Rect((Screen.width / 2) - (width / 2),
                (Screen.height / 2) - (height / 2),
                width,
                height);
        }

        private void DrawWindow(int windowId)
        {
            GUI.Label(new Rect(0, 35, 500, 20), $"Loading bundle: {current} / {maximum}", labelStyle);
            GUI.Label(new Rect(0, 50, 500, 20), bundleName, labelStyle);
        }
    }
}