using Godot;
using System;

public enum Scenes
{
    Menu,
    Game,
    End
}

public partial class SceneManager : Node
{
    public static SceneManager Instance;
    
    [Export] private Node _root;

    [Export] private PackedScene _gameScene;
    [Export] private PackedScene _menuScene;
    [Export] private PackedScene _endScene;

    private Node _game;
    private Node _menu;
    private Node _end;

    public override void _Ready()
    {
        Instance = this;
        CallDeferred(nameof(EnterMenu));
    }

    public void ChangeScene(Scenes s)
    {
        GetTree().Paused = false;
        switch (s)
        {
            case Scenes.Menu:
                EnterMenu();
                break;
            case Scenes.Game:
                EnterGame();
                break;
            case Scenes.End:
                EnterEnd();
                break;
            default:
                throw new ArgumentOutOfRangeException(nameof(s), s, null);
        }
    }

    private void EnterMenu()
    {
        RemoveScene(ref _game);
        RemoveScene(ref _end);
        AddScene(ref _menuScene, ref _menu);
    }

    private void EnterGame()
    {
        RemoveScene(ref _menu);
        RemoveScene(ref _end);
        AddScene(ref _gameScene, ref _game);
    }

    private void EnterEnd() // Not the Minecraft
    {
        RemoveScene(ref _game);
        RemoveScene(ref _menu);
        AddScene(ref _endScene, ref _end);
    }

    private void RemoveScene(ref Node n)
    {
        if (n == null) return;
        n.GetParent()?.RemoveChild(n);
        n.QueueFree();
        n = null;
    }

    private void AddScene(ref PackedScene s, ref Node n)
    {
        n = s.Instantiate();
        _root.AddChild(n);
    }
}