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using UnityEngine;
using System.Collections;

    using System.Collections.Generic;       //Allows us to use Lists. 
//https://unity3d.com/cn/learn/tutorials/projects/2d-roguelike-tutorial/writing-game-manager?playlist=17150
    
    public class GameManager : MonoBehaviour
    {

        public static GameManager instance = null;              //Static instance of GameManager which allows it to be accessed by any other script.
        private BoardManager boardScript;                       //Store a reference to our BoardManager which will set up the level.
        private int level = 3;                                  //Current level number, expressed in game as "Day 1".

        //Awake is always called before any Start functions
        void Awake()
        {
            //Check if instance already exists
            if (instance == null)
                
                //if not, set instance to this
                instance = this;
            
            //If instance already exists and it's not this:
            else if (instance != this)
                
                //Then destroy this. This enforces our singleton pattern, meaning there can only ever be one instance of a GameManager.
                Destroy(gameObject);    
            
            //Sets this to not be destroyed when reloading scene
            DontDestroyOnLoad(gameObject);
            
            //Get a component reference to the attached BoardManager script
            boardScript = GetComponent<BoardManager>();
            
            //Call the InitGame function to initialize the first level 
            InitGame();
        }
        
        //Initializes the game for each level.
        void InitGame()
        {
            //Call the SetupScene function of the BoardManager script, pass it current level number.
            boardScript.SetupScene(level);
            
        }
        
        
        
        //Update is called every frame.
        void Update()
        {
            
        }