/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.wicket.markup.html.image.resource;

import java.awt.Color;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.font.TextAttribute;
import java.util.HashMap;
import java.util.Map;

/**
 * Automatically generates a basic button image. The model for the component determines the label
 * displayed on the button.
 * 
 * @author Jonathan Locke
 */
public class DefaultButtonImageResource extends RenderedDynamicImageResource
{
        private static final long serialVersionUID = 1L;

        /** The default height for button images */
        private static int defaultHeight = 26;

        /** The default width for button images */
        private static int defaultWidth = 74;

        /** default color: orange. */
        private static final int DEFAULT_COLOR = new Color(0xE9, 0x60, 0x1A).getRGB();

        /** default background color: white. */
        private static final int DEFAULT_BACKGROUND_COLOR = Color.WHITE.getRGB();

        /** default text color: white. */
        private static final int DEFAULT_TEXT_COLOR = Color.WHITE.getRGB();

        /** default font: Helvetica bold 16. */
        private static final Map<TextAttribute, Object> DEFAULT_FONT = new HashMap<TextAttribute, Object>(
                new Font("Helvetica", Font.BOLD, 16).getAttributes());

        /**
         * @param defaultHeight
         *            The defaultHeight to set.
         */
        public static void setDefaultHeight(int defaultHeight)
        {
                DefaultButtonImageResource.defaultHeight = defaultHeight;
        }

        /**
         * @param defaultWidth
         *            The defaultWidth to set.
         */
        public static void setDefaultWidth(int defaultWidth)
        {
                DefaultButtonImageResource.defaultWidth = defaultWidth;
        }

        /** The height of the arc in the corner */
        private int arcHeight = 10;

        /** The width of the arc in the corner */
        private int arcWidth = 10;

        /** The background color behind the button */
        private int backgroundColorRgb = DEFAULT_BACKGROUND_COLOR;

        /** The color of the button itself */
        private int colorRgb = DEFAULT_COLOR;

        /** The font to use */
        private Map<TextAttribute, Object> fontAttributes = DEFAULT_FONT;

        /** The color of the text */
        private int textColorRgb = DEFAULT_TEXT_COLOR;

        /** The button label */
        private final String label;

        /**
         * @param label
         *            The label for this button image
         * @param width
         *            Width of image in pixels
         * @param height
         *            Height of image in pixels
         */
        public DefaultButtonImageResource(int width, int height, final String label)
        {
                super(width, height, "png");
                this.label = label;
                setWidth(width == -1 ? defaultWidth : width);
                setHeight(height == -1 ? defaultHeight : height);
        }

        /**
         * @param label
         *            The label for this button image
         */
        public DefaultButtonImageResource(final String label)
        {
                this(defaultWidth, defaultHeight, label);
        }

        /**
         * @return Returns the arcHeight.
         */
        public synchronized int getArcHeight()
        {
                return arcHeight;
        }

        /**
         * @return Returns the arcWidth.
         */
        public synchronized int getArcWidth()
        {
                return arcWidth;
        }

        /**
         * @return Returns the backgroundColor.
         */
        public synchronized Color getBackgroundColor()
        {
                return new Color(backgroundColorRgb);
        }

        /**
         * @return Returns the color.
         */
        public synchronized Color getColor()
        {
                return new Color(colorRgb);
        }

        /**
         * @return Returns the font.
         */
        public synchronized Font getFont()
        {
                return new Font(fontAttributes);
        }

        /**
         * @return Returns the textColor.
         */
        public synchronized Color getTextColor()
        {
                return new Color(textColorRgb);
        }

        /**
         * @param arcHeight
         *            The arcHeight to set.
         */
        public synchronized void setArcHeight(int arcHeight)
        {
                this.arcHeight = arcHeight;
                invalidate();
        }

        /**
         * @param arcWidth
         *            The arcWidth to set.
         */
        public synchronized void setArcWidth(int arcWidth)
        {
                this.arcWidth = arcWidth;
                invalidate();
        }

        /**
         * @param backgroundColor
         *            The backgroundColor to set.
         */
        public synchronized void setBackgroundColor(Color backgroundColor)
        {
                backgroundColorRgb = backgroundColor.getRGB();
                invalidate();
        }

        /**
         * @param color
         *            The color to set.
         */
        public synchronized void setColor(Color color)
        {
                colorRgb = color.getRGB();
                invalidate();
        }

        /**
         * @param font
         *            The font to set.
         */
        public synchronized void setFont(Font font)
        {
                fontAttributes = new HashMap<>(font.getAttributes());
                invalidate();
        }

        /**
         * @param textColor
         *            The textColor to set.
         */
        public synchronized void setTextColor(Color textColor)
        {
                textColorRgb = textColor.getRGB();
                invalidate();
        }

        /**
         * Renders button image.
         * 
         * @see RenderedDynamicImageResource#render(java.awt.Graphics2D, Attributes)
         */
        @Override
        protected boolean render(Graphics2D graphics, Attributes attributes)
        {
                // Get width and height
                final int width = getWidth();
                final int height = getHeight();

                // Get size of text
                graphics.setFont(getFont());
                final FontMetrics fontMetrics = graphics.getFontMetrics();
                final int dxText = fontMetrics.stringWidth(label);
                final int dxMargin = 10;

                // Does text fit with a nice margin?
                if (dxText > width - dxMargin)
                {
                        // Re-render as a larger button
                        setWidth(dxText + dxMargin);
                        return false;
                }
                else
                {
                        // Turn on anti-aliasing
                        graphics.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                                RenderingHints.VALUE_ANTIALIAS_ON);

                        // Draw background
                        Color bgColor = getBackgroundColor();
                        graphics.setColor(bgColor);
                        graphics.fillRect(0, 0, width, height);

                        // Draw round rectangle
                        graphics.setColor(getColor());
                        graphics.setBackground(bgColor);
                        graphics.fillRoundRect(0, 0, width, height, arcWidth, arcHeight);

                        // Draw text
                        graphics.setColor(getTextColor());
                        final int x = (width - dxText) / 2;
                        final int y = (getHeight() - fontMetrics.getHeight()) / 2;
                        graphics.drawString(label, x, y + fontMetrics.getAscent());
                        return true;
                }
        }
}