using System;
using System.Threading.Tasks;
using System.Collections.Generic;

using UnityEngine;
using UnityEngine.SceneManagement;

public enum Location
{
    Pechatniki,
    Sherbinka,
    BulevardSlavyanski,
    Solnechaya,
    Shukinskaya,
    AprelevkaDepo
}

public class GameSystem : MonoBehaviour
{
    public static GameSystem Instance { get; private set; }
    public List<IGameComponent> gameComponents { get; private set; } = new List<IGameComponent>();

    [SerializeField] UIMainMenu mainMenu;
    [SerializeField] UICanvas trainsMenu;
    [Space]
    public UICanvas trainEP2D;
    public UICanvas train2;
    public UICanvas train3;
    [Space]
    [SerializeField] GameObject[] sigletonComponents;

    public event Action OnSceneLoaded;

    public Dictionary<string, Location> locationsName { get; private set; } = new()
    {
        {"StationPechatnici", Location.Pechatniki},
        {"StationSherbinka", Location.Sherbinka},
        {"StationSlavyanskyBoulevard", Location.BulevardSlavyanski},
        {"StationSolnechnaya", Location.Solnechaya},
        {"StationShchukinskaya", Location.Shukinskaya},
        {"AprelevkaDepo", Location.AprelevkaDepo}
    };

    public async void LoadScene(string sceneName)
    {
        if(mainMenu.gameObject.activeSelf)
            mainMenu.Hide();
        
        mainMenu.UpdateLocationMenu(locationsName[sceneName]);

        try
        {
            var qrReader = FindObjectOfType<QRCodeReader>();
            qrReader.camTexture.Stop();
        }
        catch {}

        var sceneLoadingOperation = SceneManager.LoadSceneAsync(sceneName, LoadSceneMode.Single);
        while(!sceneLoadingOperation.isDone) await Task.Yield();

        OnSceneLoaded?.Invoke();

        FindObjectOfType<SceneHandler>().OnSceneLoaded.AddListener(()=>
        {
            mainMenu.gameObject.SetActive(true);
        });
    }

    public void ShowAboutTrain()
    {
        switch(mainMenu.currentTrain.type)
        {
            case(TrainType.EP2D):
            ShowAboutEP2D();
            break;

            case(TrainType.Ivolga2):
            ShowAboutIvolga2();
            break;

            case(TrainType.Ivolga3):
            ShowAboutIvolga3();
            break;
        }
    }

    public void ShowAboutEP2D()
    {
        train2.gameObject.SetActive(false);
        train3.gameObject.SetActive(false);

        trainsMenu.gameObject.SetActive(true);
        trainEP2D.gameObject.SetActive(true);
    }

    public void ShowAboutIvolga2()
    {
        train3.gameObject.SetActive(false);
        trainEP2D.gameObject.SetActive(false);

        trainsMenu.gameObject.SetActive(true);
        train2.gameObject.SetActive(true);
    }

    public void ShowAboutIvolga3()
    {
        train2.gameObject.SetActive(false);
        trainEP2D.gameObject.SetActive(false);

        trainsMenu.gameObject.SetActive(true);
        train3.gameObject.SetActive(true);
    }

    public void LeaveScene()
    {
        var sceneLoadingOperation = SceneManager.LoadSceneAsync("MainMenu",
            LoadSceneMode.Single);
    }

    public void AddGameComponent(IGameComponent component)
    {
        if(!gameComponents.Contains(component))
            gameComponents.Add(component);
    }

    void Awake()
    {
        foreach(var item in sigletonComponents)
            DontDestroyOnLoad(item.gameObject);

        Instance = this;
    }

    void Start()
    {
        GameSystem[] gameSystems = FindObjectsOfType<GameSystem>();
        if(gameSystems.Length > 1)
        {
            Destroy(this.gameObject);
            return;
        }

        DontDestroyOnLoad(this);
    }

    void Update()
    {
        for(int i = 0; i < gameComponents.Count; i++)
            gameComponents[i].OnUpdate();
    }

    void FixedUpdate()
    {
        for(int i = 0; i < gameComponents.Count; i++)
            gameComponents[i].OnFixedUpdate();
    }

    void LateUpdate()
    {
        for(int i = 0; i < gameComponents.Count; i++)
            gameComponents[i].OnLateUpdate();
    }

    public void RemoveGameComponent(IGameComponent component)
    {
        if(gameComponents.Contains(component))
            gameComponents.Remove(component);
    }
}