using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.GamerServices;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Media;
using Microsoft.Xna.Framework.Net;
using Microsoft.Xna.Framework.Storage;

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

        Texture2D background;
        Texture2D spotLight;
        Texture2D cs;

        Vector2 backgroundPos;
        Vector2 spotLightPos;
        Vector2 spotLightCenter;
        Vector2 csPos;

        Vector2 zero;
        Vector2 spotLightVelocity;

        int MaxX;
        int MinX;
        int MaxY;
        int MinY;

        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()
        {
            // TODO: Add your initialization logic here
            graphics.PreferredBackBufferWidth = 800;
            graphics.PreferredBackBufferWidth = 600;
            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);
            background = Content.Load<Texture2D>("background");
            spotLight = Content.Load<Texture2D>("spotlight");
            cs = Content.Load<Texture2D>("cs");
            backgroundPos = new Vector2(0f, 0f);
            spotLightPos = new Vector2(100f, graphics.GraphicsDevice.Viewport.Height - 98);
            spotLightCenter = new Vector2(800f, 800f);
            spotLightVelocity = new Vector2(-100, 33);
            csPos = new Vector2(10f, graphics.GraphicsDevice.Viewport.Height - 98);
  
            zero = new Vector2(0, 0);

            MaxX = graphics.GraphicsDevice.Viewport.Width;
            MinX = 0;
            MaxY = graphics.GraphicsDevice.Viewport.Height;
            MinY = 100;
            // TODO: use this.Content to load your game content here
        }

        /// <summary>
        /// UnloadContent will be called once per game and is the place to unload
        /// all 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)
        {
            // Allows the game to exit
            if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
                this.Exit();

            // TODO: Add your update logic here
            UpdateSpotLight(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(SpriteBlendMode.AlphaBlend);
            // TODO: Add your drawing code here
            spriteBatch.Draw(background, backgroundPos, null, Color.White, 0, zero, 0.5f, SpriteEffects.None, 0);
            spriteBatch.Draw(cs, csPos, null, Color.White, 0, zero, 0.5f, SpriteEffects.None, 0);
            spriteBatch.Draw(spotLight, spotLightPos, null, Color.White, 0, spotLightCenter, 1f, SpriteEffects.None, 0);

            spriteBatch.End();
            base.Draw(gameTime);
        }

        private void UpdateSpotLight(GameTime gameTime)
        {
            spotLightPos = new Vector2(spotLightPos.X + spotLightVelocity.X * (float)gameTime.ElapsedGameTime.TotalSeconds,
                                        spotLightPos.Y + spotLightVelocity.Y * (float)gameTime.ElapsedGameTime.TotalSeconds);

            if (spotLightPos.X > MaxX || spotLightPos.X < MinX) //right or left wall
            {
                spotLightVelocity = new Vector2(spotLightVelocity.X * -1, spotLightVelocity.Y);
            }
            else if (spotLightPos.Y > MaxY || spotLightPos.Y < MinY) //top or bottom wall
            {
                spotLightVelocity = new Vector2(spotLightVelocity.X, spotLightVelocity.Y * -1);
            }
        }
    }
}