using System;
using System.Collections;
using Settings;
using Sirenix.OdinInspector;
using UnityEngine;
using UnityEngine.SceneManagement;

namespace Core
{
    public enum SceneList
    {
        MainLoading = 0,
        InGame = 1
    }
    
    public class Application : BaseMonoBehaviour
    {
        private static Application _instance;

        public static AppParameters Parameters => _instance.parameters;
        public static GameConfiguration Configuration => _instance.configuration;

        [SerializeField] [Required] private AppParameters parameters;
        [SerializeField] [Required] private GameConfiguration configuration;
        [SerializeField] [Required] private EntryPoint sceneEntry;
        
        public bool AppStarted { get; private set; }

        protected override void ReleaseReferences()
        {
            _instance = null;
        }
        
        private void Awake()
        {
            if (_instance != null) return;
            _instance = this;
        }

        private void Start()
        {
            sceneEntry.Initialize();
            StartApp();
        }

        private void Update()
        {
            if (!AppStarted) return;
            sceneEntry.Tick();
        }

        private void StartApp()
        {
            sceneEntry.StartControllers();
            AppStarted = true;
            sceneEntry.Execute();
        }
        
        public static T GetSystem<T>() where T : SystemBase
        {
            if (_instance == null) return null;
            return _instance.sceneEntry.GetSystem<T>();
        }
    
        public static T GetPanel<T>() where T : PanelBase
        {
            if (_instance == null) return null;
            return _instance.sceneEntry.GetPanel<T>();
        }

        public static void ExitApp() => UnityEngine.Application.Quit();

        public static void LoadScene(SceneList inScene, Action onLoadComplete = null)
        {
            _instance.StartCoroutine(LoadSceneAsync(inScene, onLoadComplete));
            /*SceneManager.sceneLoaded += OnSceneLoaded;
            SceneManager.LoadSceneAsync((int) inScene);
            return;
            void OnSceneLoaded(Scene scene, LoadSceneMode loadMode) => onLoadComplete?.Invoke();*/
        }

        private static IEnumerator LoadSceneAsync(SceneList inScene, Action onLoadComplete = null)
        {
            var operation = SceneManager.LoadSceneAsync((int) inScene);
            while (!operation.isDone) yield return null;
            onLoadComplete?.Invoke();
        }
        
        // TODO: Add tracking for previous/current scenes?
        // TODO: Add CommandSystem
        // TODO: Add progress tracking for scene loading? (Make it a command?)
    }
}