using System;
using System.Threading;
using Cysharp.Threading.Tasks;
using RebootKit.Engine.Foundation;
using RebootKit.Engine.Services.Console;
using RebootKit.Engine.Services.Game;
using RebootKit.Engine.Services.Input;
using RebootKit.Engine.Services.Simulation;
using UnityEngine;
using UnityEngine.SceneManagement;
using Logger = RebootKit.Engine.Foundation.Logger;

namespace RebootKit.Engine {

    public abstract class RAsset : ScriptableObject {
        
    }
    
    public class RR : IDisposable {
        public static RR Shared { get; set; }

        private static readonly Logger _logger = new Logger("RR");

        private EngineConfigAsset _engineConfigAsset;

        private ConsoleService _consoleService;
        private InputService _inputService;
        private WorldService _worldService;
        private GameService _gameService;

        public void Dispose() {
        }

        public async UniTask Init(CancellationToken cancellationToken) {
            _logger.Info("Waking up");

            _logger.Info("Loading engine config");
            _engineConfigAsset = Resources.Load<EngineConfigAsset>(RConsts.EngineConfigResourcesPath);
            if (_engineConfigAsset == null) {
                _logger.Error($"Couldn't load engine config from resources: {RConsts.EngineConfigResourcesPath}");
                return;
            }

            _logger.Info("Loading engine found");

            await CreateCoreServices(cancellationToken);
            await RegisterServiceAssetsFromConfig(cancellationToken);
            await RegisterServicesFromMainSceneAsync(cancellationToken);
        }

        public async UniTask Run(CancellationToken cancellationToken) {
            _logger.Info($"Starting initial game mode");
            await _gameService.Start(_engineConfigAsset.StartingGameMode, cancellationToken);
        }

        private async UniTask<TService> CreateServiceAsync<TService>(ServiceAsset<TService> asset, CancellationToken cancellationToken = default) where TService : IService {
            TService service = asset.Create();
            await ServicesLocator.Shared.RegisterAsync(service, cancellationToken);

            return service;
        }

        private async UniTask CreateCoreServices(CancellationToken cancellationToken) {
            _logger.Debug("Registering core services");
            
            _consoleService = await CreateServiceAsync(_engineConfigAsset.ConsoleService, cancellationToken);
            _inputService = await CreateServiceAsync(_engineConfigAsset.InputService, cancellationToken);
            _worldService = await CreateServiceAsync(_engineConfigAsset.WorldService, cancellationToken);
            _gameService = await CreateServiceAsync(_engineConfigAsset.GameService, cancellationToken);
        }

        private async UniTask RegisterServiceAssetsFromConfig(CancellationToken cancellationToken = default) {
            if (_engineConfigAsset.Services.Length == 0) {
                return;
            }

            _logger.Info($"Registering {_engineConfigAsset.Services.Length} services");
            foreach (ServiceAsset service in _engineConfigAsset.Services) {
                await ServicesLocator.Shared.RegisterAsync(service.Create(), cancellationToken);
            }
        }

        private async UniTask RegisterServicesFromMainSceneAsync(CancellationToken cancellationToken = default) {
            _logger.Info("Looking for services in mainscene");
            int foundCount = 0;

            GameObject[] gameObjects = SceneManager.GetSceneByBuildIndex(RConsts.MainSceneBuildIndex).GetRootGameObjects();

            if (gameObjects.Length == 0) {
                _logger.Info("No services found in main scene");
                return;
            }

            foreach (GameObject root in gameObjects) {
                ServiceMonoBehaviour[] services = root.GetComponentsInChildren<ServiceMonoBehaviour>();

                foreach (ServiceMonoBehaviour service in services) {
                    await ServicesLocator.Shared.RegisterAsync(service, cancellationToken);
                    foundCount += 1;
                }
            }

            _logger.Info($"Found and registered {foundCount} services from active scene");
        }

        //
        // API
        //

        /// Services
        public static T Service<T>() where T : IService {
            return ServicesLocator.Shared.Get<T>();
        }

        public static ConsoleService Console() => Shared._consoleService;
        public static InputService Input() => Shared._inputService;
        public static WorldService World() => Shared._worldService;
        public static GameService Game() => Shared._gameService;

        /// CVars
        public static CVar CVarIndex(string name, int defaultValue = -1) {
            CVar cvar = Console().GetCVar(name);
            if (cvar != null) {
                return cvar;
            }

            cvar = new CVar(name, defaultValue);
            Console().Replace(cvar);
            return cvar;
        }

        public static CVar CVarNumber(string name, double defaultValue = 0) {
            CVar cvar = Console().GetCVar(name);
            if (cvar != null) {
                return cvar;
            }

            cvar = new CVar(name, defaultValue);
            Console().Replace(cvar);
            return cvar;
        }

        public static CVar CVarString(string name, string defaultValue = "") {
            CVar cvar = Console().GetCVar(name);
            if (cvar != null) {
                return cvar;
            }

            cvar = new CVar(name, defaultValue);
            Console().Replace(cvar);
            return cvar;
        }
    }
}