using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Input;
using System;

/*
 * A class for representing the game world.
 */
class GameWorld
{
    /*
     * enum for different game states (playing or game over)
     */
    enum GameState
    {
        Playing, GameOver
    }

    /*
     * screen width and height
     */
    int screenWidth, screenHeight;

    /*
     * random number generator
     */
    Random random;

    /*
     * main game font
     */
    SpriteFont font;

    /*
     * sprite for representing a single tetris block element
     */
    Texture2D block, gridBlock, background;
    
    /*
     * the current game state
     */
    GameState gameState;
    Vector2 midScreen, backgroundOrigin;

    /*
     * the main playing grid
     */
    TetrisGrid grid;

    public GameWorld(int width, int height, ContentManager Content)
    {
        screenWidth = width;
        screenHeight = height;
        midScreen = new Vector2(width / 2, height / 2);
        random = new Random();
        gameState = GameState.Playing;

        gridBlock = Content.Load<Texture2D>("gridBlock");
        block = Content.Load<Texture2D>("block");
        font = Content.Load<SpriteFont>("SpelFont");
        grid = new TetrisGrid(gridBlock);
        background = Content.Load<Texture2D>("placeholder");
        backgroundOrigin = new Vector2(background.Width / 2, background.Height / 2);
    }

    public void Reset()
    {
    }

    public void HandleInput(GameTime gameTime, InputHelper inputHelper)
    {
    }

    public void Update(GameTime gameTime)
    {
    }

    public void Draw(GameTime gameTime, SpriteBatch spriteBatch)
    {
        spriteBatch.Begin();
        spriteBatch.Draw(background,midScreen - backgroundOrigin,Color.White);
        grid.Draw(gameTime, spriteBatch, gridBlock);
        spriteBatch.End();    
    }

    /*
     * utility method for drawing text on the screen
     */
    public void DrawText(string text, Vector2 positie, SpriteBatch spriteBatch)
    {
        spriteBatch.DrawString(font, text, positie, Color.Blue);
    }

    public Random Random
    {
        get { return random; }
    }

    class GameObject
    {
        protected GameObject parent = null;

        public virtual Vector2 GlobalPosition
        {
            get
            {
                if (parent != null)
                    return parent.GlobalPosition + this.GlobalPosition;
                else return this.GlobalPosition;
            }            
        }        
    }
}