/*
 * GUIPopUpPanel.cs
 * Authors:
 * 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 System;
using System.Collections.Generic;
using System.Text;
using Microsoft.Xna.Framework;

namespace tAC_Engine.GUI
{
	/// <summary>
	/// Represents a Panel that pops up with a given effect.
	/// </summary>
	public class GUIPopUpPanel : GUIPanel
	{
		#region Enums

		/// <summary>
		/// The effects that can be performed on this panel.
		/// </summary>
		public enum Effects
		{
			/// <summary>
			/// Event for zooming in
			/// </summary>
			ZOOM,
			/// <summary>
			/// Event for sliding in from the left to the right
			/// </summary>
			SLIDE_RIGHT
		}

		#endregion

		#region Fields

		// The current time in the progress of completing the effect
		float mCurrentTime = 0;

		// The amount of time it takes to complete transitioning
		int mTime = 1;

		// The copy of the true bounds of the object
		Rectangle mTrueBounds;

		// Whether we are appearing or fading
		bool mAppearOrFade = true;

		// The effect for disappearing and fading
		Effects mEffect = Effects.ZOOM;

		#endregion

		#region Properties

		/// <summary>
		/// Allows access to the position of the component.
		/// </summary>
		public override Vector2 Position
		{
			get { return mPosition; }
			set
			{
				mPosition = value;
				mTrueBounds = new Rectangle(
					(int)Position.X, (int)Position.Y,
					(int)Size.X, (int)Size.Y); ;
			}
		}

		/// <summary>
		/// Allows access to the size of the component.
		/// </summary>
		public override Vector2 Size
		{
			get { return mSize; }
			set
			{
				mSize = value;
				mTrueBounds = new Rectangle(
					(int)Position.X, (int)Position.Y,
					(int)Size.X, (int)Size.Y);
			}
		}

		/// <summary>
		/// Sets or gets the amount of time, in milliseconds, for the effect
		/// to complete.
		/// </summary>
		public int Time
		{
			get { return mTime; }
			set { mTime = value; }
		}

		/// <summary>
		/// Allows the user to view or set if it's appearing(true) or
		/// fading(false).
		/// </summary>
		public bool AppearOrFade
		{
			get { return mAppearOrFade; }
			set { mAppearOrFade = value; }
		}

		/// <summary>
		/// Adjust the effects.
		/// </summary>
		public Effects Effect
		{
			get { return mEffect; }
			set { mEffect = value; }
		}

		#endregion

		#region Constructs

		/// <summary>
		/// Base constructor.
		/// </summary>
		public GUIPopUpPanel()
		{
			// Set the initial bounds
			mBounds = new Rectangle(0, 0, 0, 0);
		}

		#endregion

		#region Behavior

		/// <summary>
		/// Call this to zoom, based on the current times, etc.
		/// </summary>
		private void Zoom()
		{
			// Set the current bounds based on the value
			float ratio = (mCurrentTime / mTime);
			int xAdj = (int)(mTrueBounds.Width * (1 - ratio) / 2);
			int yAdj = (int)(mTrueBounds.Height * (1 - ratio) / 2);
			mBounds = new Rectangle(
				mTrueBounds.X + xAdj, mTrueBounds.Y + yAdj,
				(int)(mTrueBounds.Width * ratio), (int)(mTrueBounds.Height * ratio));
		}

		/// <summary>
		/// Call this to slide right, based on the current times, etc.
		/// </summary>
		private void SlideRight()
		{
			// Set the current bounds based on the value
			float ratio = (mCurrentTime / mTime);
			int x = (int)((mTrueBounds.Right) * (1 - ratio));
			mBounds = new Rectangle(
				mTrueBounds.Left - x, mTrueBounds.Y,
				mTrueBounds.Width, mTrueBounds.Height);
		}

		#endregion

		#region Update

		/// <summary>
		/// Update the panel, altering the appearence based on the effect.
		/// </summary>
		/// <param name="gameTime">The current game time.</param>
		public override void Update(GameTime gameTime)
		{
			// Base call
			base.Update(gameTime);

			// Only if we're visible
			if (Visible)
			{
				// Change based on our state
				if (mAppearOrFade && mBounds != mTrueBounds)
				{
					// Adjust the time
					mCurrentTime += (float)gameTime.ElapsedGameTime.TotalMilliseconds;
				}
				else if(!mAppearOrFade)
				{
					// Adjust the time
					mCurrentTime -= (float)gameTime.ElapsedGameTime.TotalMilliseconds;
				}

				// If we're going either way
				if ((mAppearOrFade && mCurrentTime < mTime) ||
					(!mAppearOrFade && mCurrentTime > 0))
				{
					// Switch on the type of effect
					switch (mEffect)
					{
						// Zooming
						case Effects.ZOOM:
							Zoom();
							break;
						// Slide right
						case Effects.SLIDE_RIGHT:
							SlideRight();
							break;
					}
				}
				// Fully appeared
				else if (mAppearOrFade && mTrueBounds != mBounds)
				{
					// The value is the current bounds
					mBounds = mTrueBounds;
					Resize();
				}
				// Fully faded
				else if (!mAppearOrFade)
				{
					// Set us to invisible
					Visible = false;
				}

				// If necessary
				if (mBounds != mTrueBounds)
				{
					// Resize the screen
					Resize();
				}
			}
		}

		#endregion
	}
}