#region License
/*
MIT License
Copyright © 2006-2007 Rob Loach
http://www.robloach.net
All rights reserved.

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/
#endregion License

#region Using Statements
using System;
using System.Collections.Generic;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Storage;
#endregion

namespace PongXna
{
    /// <summary>
    ///     PongXna - A simple recreation of the classic Pong game.
    /// </summary>
    /// <remarks>Version 2.0</remarks>
    public class PongXnaGame : Game
    {
        // Graphics
        GraphicsDeviceManager graphics;
        ContentManager content;
        Dictionary<string, Texture2D> textures = new Dictionary<string, Texture2D>();
        SpriteBatch sprites;

        // Sound
        private AudioEngine audioEngine = new AudioEngine("Sounds/PongXna.xgs");
        private WaveBank waveBank;
        private SoundBank soundBank;

        // Game objects
        Entity paddle1, paddle2, ball;
        float paddleAcceleration = 12000f;

        public PongXnaGame()
        {
            // Create core components
            graphics = new GraphicsDeviceManager(this);
            content = new ContentManager(Services);
            waveBank = new WaveBank(audioEngine, "Sounds/PongXnaWaves.xwb");
            soundBank = new SoundBank(audioEngine, "Sounds/PongXnaSounds.xsb");
        }

        protected override void BeginRun()
        {
            // Set the initial states of the entities
            float paddleWidth = textures["paddle1"].Width * 1.5f;
            float paddleHeight = textures["paddle1"].Height * 1.5f;
            paddle1 = new Entity(20, (float)Window.ClientBounds.Height / 2f - paddleHeight / 2f, paddleWidth, paddleHeight);
            paddle2 = new Entity(Window.ClientBounds.Width - 20 - paddleWidth, (float)Window.ClientBounds.Height / 2f - paddleHeight, paddleWidth, paddleHeight);
            ball = new Entity((float)Window.ClientBounds.Width / 2f - ball.Size.X / 2f, (float)Window.ClientBounds.Height / 2f - ball.Size.Y / 2f, textures["ball"].Width * 2, textures["ball"].Height * 2);
            ball.Speed.X = ball.Speed.Y = 150f;
        }

        protected override void LoadGraphicsContent(bool loadAllContent)
        {
            // Load all graphics content using the content manager
            if (loadAllContent)
            {
                textures["background"] = content.Load<Texture2D>("Graphics/background");
                textures["ball"] = content.Load<Texture2D>("Graphics/ball");
                textures["paddle1"] = content.Load<Texture2D>("Graphics/paddle1");
                textures["paddle2"] = content.Load<Texture2D>("Graphics/paddle2");
                sprites = new SpriteBatch(this.graphics.GraphicsDevice);
            }
        }

        protected override void UnloadGraphicsContent(bool unloadAllContent)
        {
            // Dispose of any allocated memory
            if (unloadAllContent)
                content.Unload();
            sprites.Dispose();
            audioEngine.Dispose();
            waveBank.Dispose();
            soundBank.Dispose();
        }

        protected override void Update(GameTime gameTime)
        {
            // Update the game world based on elapsed time
            float elapsed = (float)gameTime.ElapsedRealTime.TotalSeconds;

            // Update locations of entities
            paddle1.Position.Y += paddle1.Speed.Y * elapsed;
            paddle2.Position.Y += paddle2.Speed.Y * elapsed;
            ball.Position.X += ball.Speed.X * elapsed;
            ball.Position.Y += ball.Speed.Y * elapsed;

            // Check for round winning conditions
            if (ball.Speed.X < 0f) // left side
            {
                if (ball.Position.X + ball.Size.X < 0f)
                    ResetBall();
                else
                {
                    if ((ball.Position.X < paddle1.Position.X + paddle1.Size.X && ball.Position.X + ball.Size.X > paddle1.Position.X)
                        && (ball.Position.Y > paddle1.Position.Y)
                        && (ball.Position.Y < paddle1.Position.Y + paddle1.Size.Y))
                    {
                        soundBank.PlayCue("bounce");
                        ball.Speed.X *= -1.1f;
                    }
                }
            }
            else // right side
            {
                if (ball.Position.X > Window.ClientBounds.Width)
                    ResetBall();
                else
                {
                    if ((ball.Position.X + ball.Size.X > paddle2.Position.X && ball.Position.X < paddle2.Position.X + paddle2.Size.X)
                        && (ball.Position.Y > paddle2.Position.Y)
                        && (ball.Position.Y < paddle2.Position.Y + paddle2.Size.Y))
                    {
                        soundBank.PlayCue("bounce2");
                        ball.Speed.X *= -1.1f;
                    }
                }
            }

            // Ball bounce off of wall
            if ((ball.Speed.Y < 0f && ball.Position.Y < 0f) || (ball.Speed.Y > 0f && ball.Position.Y + ball.Size.Y > Window.ClientBounds.Height))
            {
                soundBank.PlayCue("wall");
                ball.Speed.Y *= -1f;
            } 

            // Move AI player
            if (ball.Speed.X > 0)
            {
                if (paddle2.Position.Y + (float)paddle2.Size.Y / 2f < ball.Position.Y + (float)ball.Size.Y / 2f)
                    paddle2.Speed.Y = paddleAcceleration * elapsed;
                else
                    paddle2.Speed.Y = -paddleAcceleration * elapsed;
            }
            else
                paddle2.Speed.Y = 0f;

            // GamePad support
            GamePadState gamepad = GamePad.GetState(PlayerIndex.One);
            if (gamepad.IsConnected)
            {
                if (gamepad.ThumbSticks.Left.Y < 0 || gamepad.DPad.Down == ButtonState.Pressed)
                    paddle1.Speed.Y = paddleAcceleration * elapsed;
                else if (gamepad.ThumbSticks.Left.Y > 0 || gamepad.DPad.Up == ButtonState.Pressed)
                    paddle1.Speed.Y = -paddleAcceleration * elapsed;
                else
                    paddle1.Speed.Y = 0f;

                if (gamepad.Buttons.Back == ButtonState.Pressed)
                    this.Exit();
            }
            else
            {
                // Use keyboard on Windows machines when there isn't a gamepad
                KeyboardState keyboard = Keyboard.GetState();
                if (keyboard.IsKeyDown(Keys.Down))
                    paddle1.Speed.Y = paddleAcceleration * elapsed;
                else if (keyboard.IsKeyDown(Keys.Up))
                    paddle1.Speed.Y = -paddleAcceleration * elapsed;
                else
                    paddle1.Speed.Y = 0f;

                if (keyboard.IsKeyDown(Keys.Escape))
                    this.Exit();
            }

            // Keep the paddles on the screen
            CheckPaddleBoundry(ref paddle1);
            CheckPaddleBoundry(ref paddle2);

            // Give the audio engine to perform periodic work
            audioEngine.Update();
            base.Update(gameTime);
        }

        protected override void Draw(GameTime gameTime)
        {
            // Draw the background and all game entities
            sprites.Begin();
            sprites.Draw(textures["background"], new Rectangle(0, 0, Window.ClientBounds.Width, Window.ClientBounds.Height), Color.White);
            paddle1.Draw(sprites, textures["paddle1"]);
            paddle2.Draw(sprites, textures["paddle2"]);
            ball.Draw(sprites, textures["ball"]);
            sprites.End();

            base.Draw(gameTime);
        }

        private void ResetBall()
        {
            ball.Speed.X = ball.Speed.Y = 150f;
            ball.Position = new Vector2((float)Window.ClientBounds.Width / 2f - ball.Size.X / 2f, (float)Window.ClientBounds.Height / 2f - ball.Size.Y / 2f);
            soundBank.PlayCue("win");
        }

        private void CheckPaddleBoundry(ref Entity paddle)
        {
            if (paddle.Position.Y + paddle.Size.Y > Window.ClientBounds.Height)
                paddle.Position.Y = Window.ClientBounds.Height - paddle.Size.Y;
            else if (paddle.Position.Y < 0f)
                paddle.Position.Y = 0f;
        }
    }
}