using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using System.Collections.Generic;
using Tutorial023.Misc;
using Tutorial023.Sprites;

namespace Tutorial023
{
  /// <summary>
  /// This is the main type for your game.
  /// </summary>
  public class Game1 : Game
  {
    GraphicsDeviceManager graphics;
    SpriteBatch spriteBatch;

    public static int ScreenWidth = 1280;
    public static int ScreenHeight = 720;

    private List<ScrollingBackground> _scrollingBackgrounds;

    private Player _player;

    public Game1()
    {
      graphics = new GraphicsDeviceManager(this);
      Content.RootDirectory = "Content";
    }

    /// <summary>
    /// Allows the game to perform any initialization it needs to before starting to run.
    /// This is where it can query for any required services and load any non-graphic
    /// related content.  Calling base.Initialize will enumerate through any components
    /// and initialize them as well.
    /// </summary>
    protected override void Initialize()
    {
      graphics.PreferredBackBufferWidth = ScreenWidth;
      graphics.PreferredBackBufferHeight = ScreenHeight;
      graphics.ApplyChanges();

      base.Initialize();
    }

    /// <summary>
    /// LoadContent will be called once per game and is the place to load
    /// all of your content.
    /// </summary>
    protected override void LoadContent()
    {
      // Create a new SpriteBatch, which can be used to draw textures.
      spriteBatch = new SpriteBatch(GraphicsDevice);

      var boyTexture = Content.Load<Texture2D>("boy");

      _player = new Player(boyTexture)
      {
        Position = new Vector2(50, (ScreenHeight - boyTexture.Height) - 20),
        Layer = 1f,
      };

      _scrollingBackgrounds = new List<ScrollingBackground>()
      {
        new ScrollingBackground(Content.Load<Texture2D>("ScrollingBackgrounds/Trees"), _player, 60f)
        {
          Layer = 0.99f,
        },
        new ScrollingBackground(Content.Load<Texture2D>("ScrollingBackgrounds/Floor"), _player, 60f)
        {
          Layer = 0.9f,
        },
        new ScrollingBackground(Content.Load<Texture2D>("ScrollingBackgrounds/Hills_Front"), _player, 40f)
        {
          Layer = 0.8f,
        },
        new ScrollingBackground(Content.Load<Texture2D>("ScrollingBackgrounds/Hills_Middle"), _player, 30f)
        {
          Layer = 0.79f,
        },
        new ScrollingBackground(Content.Load<Texture2D>("ScrollingBackgrounds/Clouds_Fast"), _player, 25f, true)
        {
          Layer = 0.78f,
        },
        new ScrollingBackground(Content.Load<Texture2D>("ScrollingBackgrounds/Hills_Back"), _player, 0f)
        {
          Layer = 0.77f,
        },
        new ScrollingBackground(Content.Load<Texture2D>("ScrollingBackgrounds/Clouds_Slow"), _player, 10f, true)
        {
          Layer = 0.7f,
        },
        new ScrollingBackground(Content.Load<Texture2D>("ScrollingBackgrounds/Sky"), _player, 0f)
        {
          Layer = 0.1f,
        },
      };
    }

    /// <summary>
    /// UnloadContent will be called once per game and is the place to unload
    /// game-specific content.
    /// </summary>
    protected override void UnloadContent()
    {
      // TODO: Unload any non ContentManager content here
    }

    /// <summary>
    /// Allows the game to run logic such as updating the world,
    /// checking for collisions, gathering input, and playing audio.
    /// </summary>
    /// <param name="gameTime">Provides a snapshot of timing values.</param>
    protected override void Update(GameTime gameTime)
    {
      _player.Update(gameTime);

      foreach (var sb in _scrollingBackgrounds)
        sb.Update(gameTime);

      base.Update(gameTime);
    }

    /// <summary>
    /// This is called when the game should draw itself.
    /// </summary>
    /// <param name="gameTime">Provides a snapshot of timing values.</param>
    protected override void Draw(GameTime gameTime)
    {
      GraphicsDevice.Clear(Color.CornflowerBlue);

      spriteBatch.Begin(SpriteSortMode.FrontToBack, null, SamplerState.PointClamp);

      _player.Draw(gameTime, spriteBatch);

      foreach (var sb in _scrollingBackgrounds)
        sb.Draw(gameTime, spriteBatch);

      spriteBatch.End();

      base.Draw(gameTime);
    }
  }
}