using System;
using System.Collections.Generic;
using UnityEngine;

namespace Core
{
    public class PermanentController : BaseMonoBehaviour
    {
        private static PermanentController _instance;
        
        private Dictionary<Type, SystemBase> _systems;

        private HashSet<ITick> _tickSystems;

        private bool _isInitialized;
        
        protected override void ReleaseReferences()
        {
            _systems = null;
            _tickSystems = null;
        }

        private void Awake()
        {
            if (_instance != null)
            {
                Destroy(gameObject);
                return;
            }

            _instance = this;
            DontDestroyOnLoad(gameObject);
        }

        public static void Initialize()
        {
            if (_instance._isInitialized) return;
            _instance._isInitialized = true;
            
            _instance._systems = new Dictionary<Type, SystemBase>();
            _instance._tickSystems = new HashSet<ITick>();
            
            foreach (Transform trSystem in _instance.transform)
            {
                var system = trSystem.gameObject.GetComponent<SystemBase>();
                if (system == null)
                {
                    Debug.LogWarning($"{trSystem.gameObject.name} must inherit from SystemBase");
                    continue;
                }
                
                _instance._systems.Add(system.GetType(), system);
                system.Initialize();

                if (system is ITick tick) 
                    _instance._tickSystems.Add(tick);
            }
        }

        public static void Tick()
        {
            foreach (var system in _instance._tickSystems) 
                system?.Tick();
        }
        
        public static void StartControllers()
        {
            foreach (var system in _instance._systems.Values) 
                if (system.AutoStart) system.StartSystem();
        }
        
        public static T GetSystem<T>() where T : SystemBase
        {
            if (!_instance._systems.ContainsKey(typeof(T))) return null;
            return (T) _instance._systems[typeof(T)];
        }
        
        // public static bool HasSystem<T>() where T : SystemBase => _instance._systems.ContainsKey(typeof(T));
    }
}