using System.Collections.Generic;
using UnityEngine;

public class Singleton<Instance> : MonoBehaviour where Instance : Singleton<Instance>
{
    public bool isPersistant = true;

    public virtual void Awake()
    {
        if (instances == null)
            instances = new Dictionary<string, Instance>();

        string scene_name = gameObject.scene.name;

        if (isPersistant)
        {
            if (instances.Count == 0)
            {
                instances.Add("", this as Instance);
                DontDestroyOnLoad(gameObject);
            }
            else
            {
                DestroyObject(gameObject);
            }
        }
        else
        {
            if (instances.ContainsKey(scene_name) == false)
                instances.Add(scene_name, this as Instance);
        }
    }

    static Dictionary<string, Instance> instances;

    ///<summary>
    ///name = gameObject.scene.name
    ///</summary>
    public static Instance GetInstance(string name = "")
    {
        string key = instances.ContainsKey(name) ? name : "";
        return instances.ContainsKey(name) ? instances[key] : null;
    }
}