/*
 * Util.MenuScreen.cs
 * Authors: Adam Nabinger
 * Copyright (c) 2007-2008 Cornell University

 This program is free software; you can redistribute it and/or
 modify it under the terms of the GNU General Public License
 as published by the Free Software Foundation; either version 2
 of the License, or (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*/

using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;

namespace Util
{

	internal enum MenuEventCode
	{
		MenuSelect = 1001,
		MenuCancel = 1002,
	}

	/// <summary>
	/// A generic menu screen.
	/// </summary>
	public class MenuScreen : GameScreen
    {
        #region Fields

        /// <summary>
        /// Reference to the current sprite batch used for rendering
        /// </summary>
		protected SpriteBatch m_SpriteBatch;

        /// <summary>
        /// The menu screens handler for any input
        /// </summary>
		protected InputHandler inputHandler;

        /// <summary>
        /// Reference to the game screen which created this
        /// </summary>
		protected readonly GameScreen m_Game;

        /// <summary>
        /// The texture used as the background of this screen
        /// </summary>
		protected Texture2D mBackground;

        /// <summary>
        /// The location and dimensions of this screen
        /// </summary>
		protected Rectangle mBackgroundLocation;

        /// <summary>
        /// Array of buttons that can be clicked on in the menu screen
        /// </summary>
		protected MenuButton[] mButtons;

		/// <summary>
		/// The image for the mouse pointer
		/// </summary>
		protected Texture2D mMousePointer;

        /// <summary>
        /// The location and dimensions of the mouse pointer
        /// </summary>
		protected Rectangle mMouseLocation;

        #endregion

        #region Creation

        /// <summary>
        /// Constructor
        /// </summary>
        /// <param name="game">Reference to the current game screen</param>
        public MenuScreen(GameScreen game)
		{
			m_Game = game;
			mButtons = new MenuButton[0];
        }

        #endregion

        #region Initialization

        /// <summary>
		/// Initialize.
		/// </summary>
		public override void Initialize()
		{
			inputHandler = GetInputHandler();
			inputHandler.Initialize();
			inputHandler.BindButton(MouseButton.Left, Trigger.Activated, (int)MenuEventCode.MenuSelect);
            inputHandler.BindButton(Microsoft.Xna.Framework.Input.Keys.Escape, Trigger.Activated, (int)MenuEventCode.MenuCancel);
			base.Initialize();
		}

        /// <summary>
        /// The menuscreen should not be drawn over.
        /// </summary>
        public override void Reinitialize() { }

        #endregion

        #region Management

        /// <summary>
		/// Loads in all necessary information for all content dependent objects
		/// </summary>
		protected override void LoadContent()
		{
			m_SpriteBatch = new SpriteBatch(GraphicsDevice);
			foreach (MenuButton b in mButtons)
			{
				b.LoadContent(Content);
			}
			base.LoadContent();
		}

        /// <summary>
        /// Disposes of any unmanged objects
        /// </summary>
		/// <param name="disposing">Whether or not this is currently being disposed</param>
		protected override void Dispose(bool disposing)
		{
			if (disposing)
			{
				m_SpriteBatch.Dispose();
			}
			base.Dispose(disposing);
        }

        #endregion

        #region Update

        /// <summary>
        /// Updates the menu screen
        /// </summary>
        /// <param name="gameTime">Time that has passed in game</param>
		public override void Update(GameTime gameTime)
		{
			Point tempLocation = inputHandler.MouseLocation;

			mMouseLocation.X = tempLocation.X;
			mMouseLocation.Y = tempLocation.Y;

			foreach (MenuButton mb in mButtons)
			{
				MenuButtonHover mbh = mb as MenuButtonHover;
				if (mbh != null)
				{
					mbh.Update(mbh.Location.Contains(mMouseLocation));
				}
			}

			while (inputHandler.HasEvent())
			{
				InputEvent e = inputHandler.GetNextEvent();
				switch ((MenuEventCode)e.EventCode)
				{
					case MenuEventCode.MenuSelect:
						MouseInputEvent me = e as MouseInputEvent;
						if (me == null)
						{
							break;
						}
						foreach (MenuButton b in mButtons)
						{
							if (b.Location.Contains(me.Location))
							{
								Enabled = false;
								Visible = false;
								inputHandler.Disable();
								b.Execute(m_Game);
								return;
							}
						}
						break;
					case MenuEventCode.MenuCancel:
						Done();
						return;
				}
			}
			base.Update(gameTime);
        }

        #endregion

        #region Render

        /// <summary>
        /// Renders the menu screen
        /// </summary>
		/// <param name="gameTime">Time that has passed in game</param>
		public override void Draw(GameTime gameTime)
		{
			m_SpriteBatch.Begin();
			if (mBackground != null)
			{
				m_SpriteBatch.Draw(mBackground, mBackgroundLocation, Color.White);
			}
			foreach (MenuButton b in mButtons)
			{
				b.Draw(m_SpriteBatch);
			}
			if (mMousePointer != null)
			{
				m_SpriteBatch.Draw(mMousePointer, mMouseLocation, Color.White);
			}
			m_SpriteBatch.End();
			base.Draw(gameTime);
        }

        #endregion
    }
}