Danro-Jump/Assets/Scripts/Runtime/Bootstrap/BootstrapEntryPoint.cs

using System.Collections;
using System.IO;
using UnityEngine;
using UnityEngine.SceneManagement;

namespace DanroJump.Bootstrap
{
    [DefaultExecutionOrder(-10000)]
    public sealed class BootstrapEntryPoint : MonoBehaviour
    {
        [SerializeField] private string mainMenuSceneName = "MainMenu";

        private IEnumerator Start()
        {
            if (string.IsNullOrWhiteSpace(mainMenuSceneName))
            {
                Debug.LogError("[BootstrapEntryPoint] Main menu scene name is empty.", this);
                yield break;
            }

            if (!SceneExistsInBuildSettings(mainMenuSceneName))
            {
                Debug.LogError($"[BootstrapEntryPoint] Scene '{mainMenuSceneName}' is not registered in Build Settings.", this);
                yield break;
            }

            AsyncOperation operation = SceneManager.LoadSceneAsync(mainMenuSceneName, LoadSceneMode.Single);
            if (operation == null)
            {
                Debug.LogError($"[BootstrapEntryPoint] Failed to start loading scene '{mainMenuSceneName}'.", this);
                yield break;
            }

            while (!operation.isDone)
                yield return null;
        }

        private static bool SceneExistsInBuildSettings(string sceneName)
        {
            for (int i = 0; i < SceneManager.sceneCountInBuildSettings; i++)
            {
                string scenePath = SceneUtility.GetScenePathByBuildIndex(i);
                string buildSceneName = Path.GetFileNameWithoutExtension(scenePath);

                if (buildSceneName == sceneName)
                    return true;
            }

            return false;
        }
    }
}