/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2012 by Rapid-I and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapid-i.com
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 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 Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see http://www.gnu.org/licenses/.
 */
package com.rapidminer.gui.tools;

import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;

import javax.swing.JPanel;

/**
 * This panel can be used to display some text.
 *
 * @author Ingo Mierswa
 */
public class TextPanel extends JPanel {
	
	private static final long serialVersionUID = -5728947680003081065L;

	public static final int ALIGNMENT_LEFT = 0;
	
	public static final int ALIGNMENT_RIGHT = 1;
	
	public static final int ALIGNMENT_TOP = 0;
	
	public static final int ALIGNMENT_BOTTOM = 1;
	
	protected static final Font TITLE_FONT = new Font("SansSerif", java.awt.Font.BOLD, 12);
	
	protected static final Font TEXT_FONT = new Font("SansSerif", java.awt.Font.PLAIN, 11);
	
	protected static final int LINE_HEIGHT = 16;
	
	protected static final int MARGIN = 24;
	
	protected static final int TITLE_MARGIN = 5;
	
	private String title;
	
	private String[] textLines;
	
	private int height;
	
	private int width;
	
	private int xAlignment = ALIGNMENT_RIGHT;
	
	private int yAlignment = ALIGNMENT_TOP;
	
	private boolean resized = false;
	
	public TextPanel(String title, String[] textLines, int xAlignment, int yAlignment) {
		this.title = title;
		this.xAlignment = xAlignment;
		this.yAlignment = yAlignment;
		setText(textLines);
		setOpaque(false);
	}
	
	public void setText(String[] textLines) {
		this.textLines = textLines;
		this.height = LINE_HEIGHT + TITLE_MARGIN + textLines.length * LINE_HEIGHT + MARGIN;
		resized = false;
	}
	
	@Override
	public void paintComponent(Graphics graphics) {
		super.paintComponent(graphics);
		Graphics2D g = (Graphics2D)graphics;
		
		this.width = 1;
		
		g.setColor(SwingTools.BROWN_FONT_COLOR);
		g.setFont(TITLE_FONT);
		int yPos = getTextStartY();
		drawString(g, title, yPos);
		Rectangle2D stringBounds = g.getFontMetrics().getStringBounds(title, g);
		this.width = (int)Math.max(this.width, stringBounds.getWidth());
		
		yPos += TITLE_MARGIN;
		g.setFont(TEXT_FONT);
		for (String line : textLines) {
			yPos += LINE_HEIGHT;
			drawString(g, line, yPos);
			stringBounds = g.getFontMetrics().getStringBounds(line, g);
			this.width = (int)Math.max(this.width, stringBounds.getWidth());
		}
		
		this.width += 2 * MARGIN;
		Dimension dimension = new Dimension(this.width, this.height);
		setPreferredSize(dimension);
		
		//paintChildren(graphics);
		
        // necessary for activating scroll bars if necessary
        if (!resized) {
            revalidate();
            repaint();
            resized = true;
        }
	}
	
	private void drawString(Graphics2D g, String text, int height) {
		switch (xAlignment) {
		case ALIGNMENT_LEFT:
			float xPos = MARGIN;
			float yPos = height;
			g.drawString(text, xPos, yPos);
			break;
		case ALIGNMENT_RIGHT:
			Rectangle2D stringBounds = g.getFontMetrics().getStringBounds(text, g);
			xPos = (float)(getWidth() - MARGIN - stringBounds.getWidth());
			yPos = height;
			g.drawString(text, xPos, yPos);
			break;
		}
	}
	
	protected int getTextStartY() {
		int yPos = MARGIN;
		switch (yAlignment) {
		case ALIGNMENT_TOP:
			yPos = MARGIN;
			break;
		case ALIGNMENT_BOTTOM:
			yPos = getHeight() - textLines.length * LINE_HEIGHT - MARGIN;
			break;
		}
		return yPos;
	}
}