/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License (the "License").

 * You may not use this file except in compliance with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Copyright (c) 2009, 2011, Oracle and/or its affiliates. All rights reserved.

 */

package org.opensolaris.os.vp.util.swing;

import java.awt.*;

import java.util.ArrayList;

import javax.swing.*;

import org.opensolaris.os.vp.util.misc.TextUtil;

/**

 * The {@code WrappingText} class displays multi-line text, wrapping words

 * at whitespace.

 */

@SuppressWarnings({"serial"})

public class WrappingText extends JComponent {

    //

    // Instance data

    //

    private String text;

    private int prefWidth = -1;

    private boolean prefWidthIsStatic;

    //

    // Constructors

    //

    public WrappingText(String text, int columns) {

	setText(text);

	setFont(UIManager.getFont("TextField.font"));

	setForeground(UIManager.getColor("Label.foreground"));

	setBackground(UIManager.getColor("Label.background"));

	setPreferredWidthInColumns(columns);

	setOpaque(false);

    }

    public WrappingText(String text) {

	this(text, -1);

    }

    public WrappingText() {

	this("");

    }

    public WrappingText(int columns) {

	this("", -1);

    }

    //

    // Component methods

    //

    @Override

    public void setBounds(int x, int y, int width, int height) {

	super.setBounds(x, y, width, height);

	setPreferredWidth(width);

    }

    @Override

    public void setBounds(Rectangle r) {

	super.setBounds(r);

	setPreferredWidth(r.width);

    }

    @Override

    public Dimension getMinimumSize() {

	return getPreferredSize();

    }

    @Override

    public Dimension getPreferredSize() {

	if (isPreferredSizeSet()) {

	    return super.getPreferredSize();

	}

	Insets insets = getInsets();

	FontMetrics metrics = getFontMetrics(getFont());

	String[] lines = getLines(prefWidth < 0 ?

	    Integer.MAX_VALUE : prefWidth - insets.left - insets.right);

	// Get length of longest line

	int width = 0;

	for (int i = 0; i < lines.length; i++) {

	    width = Math.max(width, metrics.stringWidth(lines[i]));

	}

	width += insets.left + insets.right;

	// Set preferred width

	if (prefWidth < 0) {

	    prefWidth = width;

	}

	int height = lines.length * metrics.getHeight() + insets.top +

	    insets.bottom;

	return new Dimension(width, height);

    }

    //

    // JComponent methods

    //

    @Override

    protected void paintComponent(Graphics g) {

	// Turn on anti-aliasing if appropriate

	GUIUtil.setAARendering((Graphics2D)g);

	if (isOpaque()) {

	    g.setColor(getBackground());

	    g.fillRect(0, 0, getWidth(), getHeight());

	}

	Font font = getFont();

	FontMetrics metrics = getFontMetrics(font);

	int rowHeight = metrics.getHeight();

	Insets insets = getInsets();

	int y = insets.top + metrics.getAscent();

	String[] lines = getLines(getWidth() - insets.left - insets.right);

	g.setColor(getForeground());

	g.setFont(font);

	for (int i = 0; i < lines.length; i++) {

	    g.drawString(lines[i], insets.left, y);

	    y += rowHeight;

	}

    }

    //

    // WrappingText methods

    //

    /**

     * Gets the initial preferred width of this {@code WrappingText}.

     * Called by {@code getPreferredSize}.  The width here is determined by

     * the number of columns, the column width, and the insets of this

     * {@code Component}.

     *

     * @return	    the preferred width in pixels, or -1 if

     *		    {@code getPreferredSize} should determine it based on

     *		    the longest line in the text

     */

    public int getPreferredWidth() {

	return prefWidth;

    }

    public boolean getPreferredWidthIsStatic() {

	return prefWidthIsStatic;

    }

    /**

     * Sets the preferred width of this {@code WrappingText}, based on the given

     * number of columns.  This value ultimately determines the preferred

     * height.

     * <p>

     * If not specified, the initial preferred width is determined by the length

     * of the longest line of text.

     *

     * @param	    prefWidth

     *		    the preferred width, in pixels

     */

    public void setPreferredWidth(int prefWidth) {

	if (this.prefWidth != prefWidth && !prefWidthIsStatic) {

	    this.prefWidth = prefWidth;

	    revalidateLater();

	}

    }

    /**

     * Sets the preferred width of this {@code WrappingText}, based on the given

     * number of columns.  Column width is the width of the character 'm' in the

     * current font.

     *

     * @param	    columns

     *		    the preferred width, in columns

     */

    public void setPreferredWidthInColumns(int columns) {

	int prefWidth = 0;

	if (columns < 0) {

	    prefWidth = -1;

	} else {

	    int columnWidth = getFontMetrics(getFont()).charWidth('m');

	    Insets insets = getInsets();

	    prefWidth = columns * columnWidth + insets.left + insets.right;

	}

	setPreferredWidth(prefWidth);

    }

    public String getText() {

	return text;

    }

    public void setPreferredWidthIsStatic(boolean prefWidthIsStatic) {

	this.prefWidthIsStatic = prefWidthIsStatic;

    }

    public void setText(String text) {

	if (text == null) {

	    text = "";

	}

	this.text = text;

	revalidateLater();

	repaint();

    }

    //

    // Private methods

    //

    private String[] getLines(int width) {

	ArrayList<String> lines = new ArrayList<String>();

	FontMetrics metrics = getFontMetrics(getFont());

	String text = getText();

	// The current line

	// Space that will be added to current line as long as it's not the last

	// token in the line

	String pendingSpace = "";

	int pendingSpaceWidth = 0;

	String[] groups;

	int x = 0;

	while ((groups = TextUtil.match(text,

	    "^((\\r?\\n)|(\\s+)|(\\S+))((?s).*)")) != null) {

	    String newline = groups[2];

	    String space = groups[3];

	    String word = groups[4];

	    text = groups[5];

	    if (newline != null) {

		lines.add(line.toString());

		line.setLength(0);

		pendingSpace = "";

		pendingSpaceWidth = 0;

		x = 0;

	    } else

	    if (space != null) {

		pendingSpace = space;

		pendingSpaceWidth = metrics.stringWidth(pendingSpace);

	    } else

	    if (word != null) {

		int wordWidth = metrics.stringWidth(word);

		int newX = x + pendingSpaceWidth + wordWidth;

		// Will the pending space and this word fit on this line?

		if (newX <= width) {

		    line.append(pendingSpace).append(word);

		    x = newX;

		} else {

		    if (line.length() != 0) {

			lines.add(line.toString());

			line.setLength(0);

		    }

		    // Does this word fit on a line of its own?

		    if (wordWidth <= width) {

			line.append(word);

			x = wordWidth;

		    } else {

			// Split word

			char[] chars = word.toCharArray();

			x = 0;

			for (int i = 0; i < chars.length; i++) {

			    char c = chars[i];

			    int charWidth = metrics.charWidth(c);

			    x += charWidth;

			    // Has this line exceeded the maximum width?

			    if (x > width && line.length() != 0) {

				lines.add(line.toString());

				line.setLength(0);

				x = charWidth;

			    }

			    line.append(c);

			}

		    }

		}

		pendingSpace = "";

		pendingSpaceWidth = 0;

	    }

	}

	if (line.length() > 0) {

	    lines.add(line.toString());

	}

	return lines.toArray(new String[lines.size()]);

    }

    private void revalidateLater() {

	SwingUtilities.invokeLater(

	    new Runnable() {

		@Override

		public void run() {

		    revalidate();

		}

	    });

    }

}