/* ========================================================================
 * PlantUML : a free UML diagram generator
 * ========================================================================
 *
 * (C) Copyright 2009-2024, Arnaud Roques
 *
 * Project Info:  https://plantuml.com
 * 
 * If you like this project or if you find it useful, you can support us at:
 * 
 * https://plantuml.com/patreon (only 1$ per month!)
 * https://plantuml.com/paypal
 * 
 * This file is part of PlantUML.
 *
 * PlantUML is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * PlantUML 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 General Public
 * License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 * USA.
 *
 *
 * Original Author:  Arnaud Roques
 *
 *
 */
package net.sourceforge.plantuml;


import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
import java.util.ArrayList;
import java.util.List;

import net.sourceforge.plantuml.dot.GraphvizUtils;
import net.sourceforge.plantuml.klimt.UAntiAliasing;
import net.sourceforge.plantuml.klimt.awt.PortableImage;
import net.sourceforge.plantuml.klimt.awt.PortableImageFactory;
import net.sourceforge.plantuml.klimt.awt.XColor;
import net.sourceforge.plantuml.klimt.font.StringBounder;
import net.sourceforge.plantuml.utils.Log;

public class EmptyImageBuilder {
	// ::remove file when __HAXE__

	private final PortableImage im;

	// ::comment when __TEAVM__
	private final Graphics2D g2d;
	// ::done

	public EmptyImageBuilder(String watermark, int width, int height, XColor background, StringBounder stringBounder) {
		if (width <= 0 || height <= 0)
			throw new IllegalArgumentException("width and height must be positive");

		// ::comment when __TEAVM__
		if (width > GraphvizUtils.getenvImageLimit()) {
			final int width2 = width;
			Log.info(() -> "Width too large " + width2 + ". You should set PLANTUML_LIMIT_SIZE");
			width = GraphvizUtils.getenvImageLimit();
		}
		if (height > GraphvizUtils.getenvImageLimit()) {
			final int height2 = height;
			Log.info(() -> "Height too large " + height2 + ". You should set PLANTUML_LIMIT_SIZE");
			height = GraphvizUtils.getenvImageLimit();
		}
		// ::done
		
		final int widthFinal = width;
		final int heightFinal = height;
		final int type = getType(background);
		Log.info(() -> "Creating image " + widthFinal + "x" + heightFinal + " type=" + type);

		im = PortableImageFactory.build(width, height, type);

		// ::comment when __TEAVM__
		g2d = im.createGraphics();
		UAntiAliasing.ANTI_ALIASING_ON.apply(g2d);
		if (background != null) {
			g2d.setColor(background.toAwtColor());
			g2d.fillRect(0, 0, width, height);
		}
		if (watermark != null) {
			final int gray = 200;
			g2d.setColor(new XColor(gray, gray, gray).toAwtColor());
			printWatermark(watermark, width, height);
		}
		// ::done
	}

	private int getType(XColor background) {
		if (background == null)
			return PortableImage.TYPE_INT_ARGB;

		if (background.getAlpha() != 255)
			return PortableImage.TYPE_INT_ARGB;

		return PortableImage.TYPE_INT_RGB;
	}

	// ::comment when __TEAVM__
	private void printWatermark(String watermark, int maxWidth, int maxHeight) {
		final Font javaFont = g2d.getFont();
		final FontMetrics fm = g2d.getFontMetrics(javaFont);
		final Rectangle2D rect = fm.getStringBounds(watermark, g2d);
		final int height = (int) rect.getHeight();
		final int width = (int) rect.getWidth();
		if (height < 2 || width < 2)
			return;

		if (width <= maxWidth) {
			for (int y = height; y < maxHeight; y += height + 1)
				for (int x = 0; x < maxWidth; x += width + 10)
					g2d.drawString(watermark, x, y);
		} else {
			final List<String> withBreaks = withBreaks(watermark, javaFont, fm, maxWidth);
			int y = 0;
			while (y < maxHeight) {
				for (String s : withBreaks) {
					g2d.drawString(s, 0, y);
					y += (int) fm.getStringBounds(s, g2d).getHeight();
				}
				y += 10;
			}
		}
	}

	private int getWidth(String line, Font javaFont, FontMetrics fm) {
		final Rectangle2D rect = fm.getStringBounds(line, g2d);
		return (int) rect.getWidth();
	}

	private List<String> withBreaks(String watermark, Font javaFont, FontMetrics fm, int maxWidth) {
		final String[] words = watermark.split("\\s+");
		final List<String> result = new ArrayList<>();
		String pending = "";
		for (String word : words) {
			final String candidate = pending.length() == 0 ? word : pending + " " + word;
			if (getWidth(candidate, javaFont, fm) < maxWidth) {
				pending = candidate;
			} else {
				result.add(pending);
				pending = word;
			}
		}
		if (pending.length() > 0)
			result.add(pending);

		return result;
	}

	public Graphics2D getGraphics2D() {
		return g2d;
	}
	// ::done

	public PortableImage getPortableImage() {
		return im;
	}

}
