/*******************************************************************************
 * Copyright (c) 2004 Actuate Corporation.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *  Actuate Corporation  - initial API and implementation
 *******************************************************************************/

package org.eclipse.birt.report.designer.internal.ui.editors.schematic;

import org.eclipse.birt.report.designer.util.ColorManager;
import org.eclipse.draw2d.Graphics;
import org.eclipse.draw2d.Polygon;
import org.eclipse.draw2d.geometry.Point;
import org.eclipse.draw2d.geometry.PointList;
import org.eclipse.draw2d.geometry.Rectangle;
import org.eclipse.swt.graphics.Color;

/**
 * Figure related utilities.
 *  
 */
public class ReportFigureUtilities
{

	private static Polygon trianglePolygon = new Polygon( );

	private static final Color[] BEVEL_COLOR = new Color[]{

			ColorManager.getColor( 212, 208, 200 ),
			ColorManager.getColor( 255, 255, 255 ),
			ColorManager.getColor( 64, 64, 64 ),
			ColorManager.getColor( 128, 128, 128 ),
	};

	private static final Color[] SHADOW_COLOR = new Color[]{

			ColorManager.getColor( 195, 195, 195 ),
			ColorManager.getColor( 210, 210, 210 ),
			ColorManager.getColor( 225, 225, 225 ),
			ColorManager.getColor( 240, 240, 240 ),

			ColorManager.getColor( 207, 207, 207 ),
			ColorManager.getColor( 219, 219, 219 ),
			ColorManager.getColor( 231, 231, 231 ),
			ColorManager.getColor( 243, 243, 243 ),

			ColorManager.getColor( 219, 219, 219 ),
			ColorManager.getColor( 228, 228, 228 ),
			ColorManager.getColor( 237, 237, 237 ),
			ColorManager.getColor( 246, 246, 246 ),

			ColorManager.getColor( 231, 231, 231 ),
			ColorManager.getColor( 237, 237, 237 ),
			ColorManager.getColor( 243, 243, 243 ),
			ColorManager.getColor( 249, 249, 249 ),

			ColorManager.getColor( 243, 243, 243 ),
			ColorManager.getColor( 246, 246, 246 ),
			ColorManager.getColor( 249, 249, 249 ),
			ColorManager.getColor( 252, 252, 252 ),
	};

	/**
	 * Gets points to construct a triangle by give height and central point.
	 * 
	 * @param triangleHeight
	 * @param triangleCenter
	 * @return
	 */
	public static int[] getTrianglePoints( int triangleHeight,
			Point triangleCenter )
	{
		int points[] = new int[6];
		int xOff = (int) ( triangleHeight * 2 * Math.tan( Math.PI / 6 ) );
		points[0] = triangleCenter.x - xOff;
		points[1] = triangleCenter.y - triangleHeight / 2;
		points[2] = triangleCenter.x + xOff;
		points[3] = triangleCenter.y - triangleHeight / 2;
		points[4] = triangleCenter.x;
		points[5] = triangleCenter.y + triangleHeight / 2;

		return points;
	}

	/**
	 * Paints a triangle using given height and central point.
	 * 
	 * @param graphics
	 * @param triangleHeight
	 * @param triangleCenter
	 */
	public static void paintTriangle( Graphics graphics, int triangleHeight,
			Point triangleCenter )
	{
		graphics.fillPolygon( getTrianglePoints( triangleHeight, triangleCenter ) );
	}

	/**
	 * Tests if the given point is inside the triangle constructed by given
	 * height and central point.
	 * 
	 * @param triangleCenter
	 * @param triangleHeight
	 * @param pt
	 * @return
	 */
	public static boolean isInTriangle( Point triangleCenter,
			int triangleHeight, Point pt )
	{
		trianglePolygon.setPoints( new PointList( getTrianglePoints( triangleHeight,
				triangleCenter ) ) );

		return trianglePolygon.containsPoint( pt );
	}

	/**
	 * Paints double arrow on list element
	 * @param graphics
	 * @param height
	 * @param center
	 */
	public static void paintDoubleArrow( Graphics graphics, int height,
			Point center )
	{
		int points[] = new int[6];
		int xOff = (int) ( height * Math.tan( Math.PI / 4 ) / 2 );
		points[0] = center.x - xOff;
		points[1] = center.y - height / 2;
		points[2] = center.x;
		points[3] = center.y;
		points[4] = center.x - xOff;
		points[5] = center.y + height / 2;

		graphics.drawPolyline( points );

		incXOffset( points, 1 );
		graphics.drawPolyline( points );

		incXOffset( points, 3 );
		graphics.drawPolyline( points );

		incXOffset( points, 1 );
		graphics.drawPolyline( points );
	}

	/**
	 * Paints expand handle
	 * @param graphics
	 * @param height
	 * @param center
	 * @param collapsed
	 */
	public static void paintExpandHandle( Graphics graphics, int height,
			Point center, boolean collapsed )
	{
		graphics.drawRectangle( center.x - height / 2,
				center.y - height / 2,
				height,
				height );

		graphics.drawLine( center.x - height / 2 + 2, center.y, center.x
				+ height / 2 - 2, center.y );

		if ( collapsed )
		{
			graphics.drawLine( center.x,
					center.y - height / 2 + 2,
					center.x,
					center.y + height / 2 - 2 );
		}
	}

	private static void incXOffset( int[] points, int offset )
	{
		for ( int i = 0; i < points.length; i += 2 )
		{
			points[i] += offset;
		}
	}

	/**
	 * Paints bevel
	 * @param graphics
	 * @param area
	 * @param rised
	 */
	public static void paintBevel( Graphics graphics, Rectangle area,
			boolean rised )
	{
		graphics.setForegroundColor( BEVEL_COLOR[rised ? 0 : 2] );
		graphics.drawLine( area.x, area.y, area.x, area.y + area.height - 2 );
		graphics.drawLine( area.x, area.y, area.x + area.width - 2, area.y );

		graphics.setForegroundColor( BEVEL_COLOR[rised ? 1 : 3] );
		graphics.drawLine( area.x + 1, area.y + 1, area.x + 1, area.y
				+ area.height - 3 );
		graphics.drawLine( area.x + 1,
				area.y + 1,
				area.x + area.width - 3,
				area.y + 1 );

		graphics.setForegroundColor( BEVEL_COLOR[rised ? 2 : 0] );
		graphics.drawLine( area.x, area.y + area.height - 1, area.x
				+ area.width - 1, area.y + area.height - 1 );
		graphics.drawLine( area.x + area.width - 1, area.y, area.x
				+ area.width - 1, area.y + area.height - 1 );

		graphics.setForegroundColor( BEVEL_COLOR[rised ? 3 : 1] );
		graphics.drawLine( area.x + 1, area.y + area.height - 2, area.x
				+ area.width - 2, area.y + area.height - 2 );
		graphics.drawLine( area.x + area.width - 2, area.y + 1, area.x
				+ area.width - 2, area.y + area.height - 2 );
	}

	/**
	 * Paints shadow
	 * @param graphics
	 * @param area
	 * @param drawTopLeft
	 */
	public static void paintShadow( Graphics graphics, Rectangle area,
			boolean drawTopLeft )
	{
		int inc = 1;
		int xoff = 4;
		int yoff = 4;
		int xlpos = area.x - 1;
		int xpos = area.x + area.width + 1;
		int ylpos = area.y - 1;
		int ypos = area.y + area.height + 1;

		if ( drawTopLeft )
		{
			inc = -1;
			xoff = -4;
			yoff = -4;
			xlpos = area.x + area.width + 1;
			xpos = area.x - 1;
			ylpos = area.y + area.height + 1;
			ypos = area.y - 1;
		}

		{
			for ( int i = 0; i < 4; i++ )
			{
				for ( int j = 0; j < 4; j++ )
				{
					graphics.setForegroundColor( SHADOW_COLOR[i * 4 + 4 + j] );
					graphics.drawPoint( xpos + i * inc, ypos + j * inc );
				}
			}
		}

		if ( area.width > 4 )
		{
			{
				for ( int i = 0; i < 4; i++ )
				{
					for ( int j = 0; j < 4; j++ )
					{
						graphics.setForegroundColor( SHADOW_COLOR[i * 4 + 4 + j] );
						graphics.drawPoint( xlpos + 8 * inc - i * inc, ypos
								+ j * inc );
					}
				}
			}

			if ( area.width > 8 )
			{
				for ( int i = 0; i < 4; i++ )
				{
					graphics.setForegroundColor( SHADOW_COLOR[i] );
					graphics.drawLine( area.x + 4 + xoff,
							ypos + inc * i,
							area.x + area.width + xoff - 4,
							ypos + inc * i );
				}
			}
		}

		if ( area.height > 4 )
		{
			{
				for ( int i = 0; i < 4; i++ )
				{
					for ( int j = 0; j < 4; j++ )
					{
						graphics.setForegroundColor( SHADOW_COLOR[i * 4 + 4 + j] );
						graphics.drawPoint( xpos + i * inc, ylpos
								+ 8 * inc - j * inc );
					}
				}
			}

			if ( area.height > 8 )
			{
				for ( int i = 0; i < 4; i++ )
				{
					graphics.setForegroundColor( SHADOW_COLOR[i] );
					graphics.drawLine( xpos + inc * i, area.y + 4 + yoff, xpos
							+ inc * i, area.y + area.height + yoff - 4 );
				}
			}
		}
	}

}