/*
 * Copyright 2004-2014 SmartBear Software
 *
 * Licensed under the EUPL, Version 1.1 or - as soon as they will be approved by the European Commission - subsequent
 * versions of the EUPL (the "Licence");
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at:
 *
 * http://ec.europa.eu/idabc/eupl
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the Licence is
 * distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the Licence for the specific language governing permissions and limitations
 * under the Licence.
*/

package org.syntax.jedit;

import java.awt.Color;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Toolkit;

/**
 * A simple text style class. It can specify the color, italic flag, and bold
 * flag of a run of text.
 *
 * @author Slava Pestov
 * @version $Id$
 */
public class SyntaxStyle {
    /**
     * Creates a new SyntaxStyle.
     *
     * @param color  The text color
     * @param italic True if the text should be italics
     * @param bold   True if the text should be bold
     */
    public SyntaxStyle(Color color, boolean italic, boolean bold) {
        this.color = color;
        this.italic = italic;
        this.bold = bold;
    }

    /**
     * Returns the color specified in this style.
     */
    public Color getColor() {
        return color;
    }

    /**
     * Returns true if no font styles are enabled.
     */
    public boolean isPlain() {
        return !(bold || italic);
    }

    /**
     * Returns true if italics is enabled for this style.
     */
    public boolean isItalic() {
        return italic;
    }

    /**
     * Returns true if boldface is enabled for this style.
     */
    public boolean isBold() {
        return bold;
    }

    /**
     * Returns the specified font, but with the style's bold and italic flags
     * applied.
     */
    public Font getStyledFont(Font font) {
        if (font == null) {
            throw new NullPointerException("font param must not" + " be null");
        }
        if (font.equals(lastFont)) {
            return lastStyledFont;
        }
        lastFont = font;
        lastStyledFont = new Font(font.getFamily(), (bold ? Font.BOLD : 0) | (italic ? Font.ITALIC : 0),
                font.getSize());
        return lastStyledFont;
    }

    /**
     * Returns the font metrics for the styled font.
     */
    public FontMetrics getFontMetrics(Font font) {
        if (font == null) {
            throw new NullPointerException("font param must not" + " be null");
        }
        if (font.equals(lastFont) && fontMetrics != null) {
            return fontMetrics;
        }
        lastFont = font;
        lastStyledFont = new Font(font.getFamily(), (bold ? Font.BOLD : 0) | (italic ? Font.ITALIC : 0),
                font.getSize());
        fontMetrics = Toolkit.getDefaultToolkit().getFontMetrics(lastStyledFont);
        return fontMetrics;
    }

    /**
     * Sets the foreground color and font of the specified graphics context to
     * that specified in this style.
     *
     * @param gfx  The graphics context
     * @param font The font to add the styles to
     */
    public void setGraphicsFlags(Graphics gfx, Font font) {
        Font _font = getStyledFont(font);
        gfx.setFont(_font);
        gfx.setColor(color);
    }

    /**
     * Returns a string representation of this object.
     */
    public String toString() {
        return getClass().getName() + "[color=" + color + (italic ? ",italic" : "") + (bold ? ",bold" : "") + "]";
    }

    // private members
    private Color color;
    private boolean italic;
    private boolean bold;
    private Font lastFont;
    private Font lastStyledFont;
    private FontMetrics fontMetrics;
}