using System;
using System.Runtime.InteropServices;
using System.IO.Ports;
using System.IO;
using System.Management;
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 iTunesLib;

namespace TapApp
{
    /// <summary>
    /// This is the main type for your game
    /// </summary>
    public class Game1 : Microsoft.Xna.Framework.Game
    {
        private GraphicsDeviceManager graphics;
        private SpriteBatch spriteBatch;
        private SpriteFont font;
        private SerialPort port;
        private iTunesApp itunes;
        private String state;
        private Texture2D whiteRectangle;
        private int barSize;
        private int verticleOffset;

        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()
        {
            port = new SerialPort("COM6", 9600);
            port.Open();
            itunes = new iTunesApp();

            this.Window.Title = "HapTunes - Haptic Interface for iTunes";
            this.Window.AllowUserResizing = true;
            this.Window.ClientSizeChanged += new EventHandler<EventArgs>(Window_ClientSizeChanged);

            verticleOffset = this.Window.ClientBounds.Height / 2 - 50;
            
            base.Initialize();
        }

        void Window_ClientSizeChanged(object sender, EventArgs e)
        {
            barSize = this.Window.ClientBounds.Width - 100 - (int)font.MeasureString("00:00").X;
            verticleOffset = this.Window.ClientBounds.Height / 2 - 50;
        }

        /// <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);
            font = Content.Load<SpriteFont>("testFont");

            barSize = this.Window.ClientBounds.Width - 100 - (int)font.MeasureString("00:00").X;

            whiteRectangle = new Texture2D(GraphicsDevice, 1, 1);
            whiteRectangle.SetData(new[] { Color.White });
        }

        /// <summary>
        /// UnloadContent will be called once per game and is the place to unload
        /// all content.
        /// </summary>
        protected override void UnloadContent()
        {
            spriteBatch.Dispose();
            whiteRectangle.Dispose();
        }

        /// <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();
            try
            {
                // We treat the queue of waiting bytes as a queue of waiting commands
                while (port.BytesToRead > 0)
                {
                    executeCommand(port.ReadByte());
                }

                // set the status string
                switch (itunes.PlayerState)
                {
                    case ITPlayerState.ITPlayerStatePlaying:
                        state = "Playing";
                        break;
                    case ITPlayerState.ITPlayerStateStopped:
                        state = "Stopped";
                        break;
                    case ITPlayerState.ITPlayerStateFastForward:
                        state = "Fast-Forwarding";
                        break;
                    case ITPlayerState.ITPlayerStateRewind:
                        state = "Rewinding";
                        break;
                }
            }
            catch(Exception e)
            {
                this.Exit();
            }

            base.Update(gameTime);
        }

        /// <summary>
        /// Execute the command associated with the passed in integer
        /// </summary>
        /// <param name="command">the command to execute</param>
        private void executeCommand(int command)
        {
            // These numbers are decided by the arduino
            // any changes should also be made there too
            switch (command)
            {
                case 0:
                    itunes.VisualsEnabled = !itunes.VisualsEnabled;
                    break;
                case 1:
                    if (itunes.PlayerState.Equals(ITPlayerState.ITPlayerStateRewind) ||
                        itunes.PlayerState.Equals(ITPlayerState.ITPlayerStateFastForward))
                    {
                        itunes.Pause();
                        itunes.Play();
                    }
                    else itunes.PlayPause();
                    break;
                case 2:
                    itunes.NextTrack();
                    break;
                case 3:
                    itunes.PreviousTrack();
                    break;
                case 4:
                    itunes.FastForward();
                    break;
                case 5:
                    itunes.Rewind();
                    break;
                case 6:
                    itunes.CurrentPlaylist.Shuffle = !itunes.CurrentPlaylist.Shuffle;
                    break;
            }
        }

        /// <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);

            try
            {
                spriteBatch.Begin();

                spriteBatch.DrawString(font, "iTunes State: " + state, new Vector2(50, verticleOffset), Color.Black);

                string duration = String.Format("{0:D2}:{1:D2}", itunes.CurrentTrack.Duration / 60, itunes.CurrentTrack.Duration % 60);
                string position = String.Format("{0:D2}:{1:D2}", itunes.PlayerPosition / 60, itunes.PlayerPosition % 60);
                int offset = barSize * itunes.PlayerPosition / itunes.CurrentTrack.Duration;

                spriteBatch.Draw(whiteRectangle, new Rectangle(49, verticleOffset + 34, barSize + 2, 22), Color.Black);
                spriteBatch.Draw(whiteRectangle, new Rectangle(50, verticleOffset + 35, barSize, 20), Color.Gray);
                spriteBatch.DrawString(font, duration, new Vector2(barSize + 55, verticleOffset + 30), Color.Black);

                spriteBatch.Draw(whiteRectangle, new Rectangle(49, verticleOffset + 34, offset + 2, 22), Color.Black);
                spriteBatch.Draw(whiteRectangle, new Rectangle(50, verticleOffset + 35, offset, 20), Color.Green);
                spriteBatch.DrawString(font, position, new Vector2(Math.Max(offset - 10, 50), verticleOffset + 32), Color.White);

                // the mass of try/catch blocks are because of the possibility of tracks
                // having unicode characters which through exceptions when being drawn.
                try
                {
                    spriteBatch.DrawString(font, "Album: " + itunes.CurrentTrack.Album, new Vector2(50, verticleOffset + 100), Color.Black);
                }
                catch
                {
                    spriteBatch.Draw(whiteRectangle, new Rectangle(50, verticleOffset + 100, this.Window.ClientBounds.Width - 50, 20), Color.CornflowerBlue);
                    spriteBatch.DrawString(font, "Album: N/A", new Vector2(50, verticleOffset + 100), Color.Black);
                }

                try
                {
                    spriteBatch.DrawString(font, "Artist: " + itunes.CurrentTrack.Artist, new Vector2(50, verticleOffset + 80), Color.Black);
                }
                catch
                {
                    spriteBatch.Draw(whiteRectangle, new Rectangle(50, verticleOffset + 80, this.Window.ClientBounds.Width - 50, 20), Color.CornflowerBlue);
                    spriteBatch.DrawString(font, "Artist: N/A", new Vector2(50, verticleOffset + 80), Color.Black);
                }
                try
                {
                    spriteBatch.DrawString(font, "Track: " + itunes.CurrentTrack.Name, new Vector2(50, verticleOffset + 60), Color.Black);
                }
                catch
                {
                    spriteBatch.Draw(whiteRectangle, new Rectangle(50, verticleOffset + 60, this.Window.ClientBounds.Width - 50, 20), Color.CornflowerBlue);
                    spriteBatch.DrawString(font, "Track: N/A", new Vector2(50, verticleOffset + 60), Color.Black);
                }             

                spriteBatch.End();
            }
            catch
            {
                //ignore
            }

            base.Draw(gameTime);
        }
    }
}