CommandConstraintOnLinks.java

/* ========================================================================
 * PlantUML : a free UML diagram generator
 * ========================================================================
 *
 * (C) Copyright 2009-2024, Arnaud Roques
 *
 * Project Info:  https://plantuml.com
 * 
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 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
 * License for more details.
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 * Original Author:  Arnaud Roques
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package net.sourceforge.plantuml.command.note;

import java.util.List;

import net.atmp.CucaDiagram;
import net.sourceforge.plantuml.abel.Link;
import net.sourceforge.plantuml.annotation.Explain;
import net.sourceforge.plantuml.command.CommandExecutionResult;
import net.sourceforge.plantuml.command.ParserPass;
import net.sourceforge.plantuml.command.SingleLineCommand2;
import net.sourceforge.plantuml.klimt.color.ColorParser;
import net.sourceforge.plantuml.klimt.color.ColorType;
import net.sourceforge.plantuml.klimt.color.NoSuchColorException;
import net.sourceforge.plantuml.regex.IRegex;
import net.sourceforge.plantuml.regex.RegexConcat;
import net.sourceforge.plantuml.regex.RegexLeaf;
import net.sourceforge.plantuml.regex.RegexResult;
import net.sourceforge.plantuml.utils.BlocLines;
import net.sourceforge.plantuml.utils.LineLocation;

public final class CommandConstraintOnLinks extends SingleLineCommand2<CucaDiagram> {

	public CommandConstraintOnLinks() {
		super(getRegexConcat());
	}

	private static IRegex getRegexConcat() {
		return RegexConcat.build(CommandConstraintOnLinks.class.getName(), RegexLeaf.start(), //
				new RegexLeaf("constraint"), //
				RegexLeaf.spaceZeroOrMore(), //
				new RegexLeaf("on"), //
				RegexLeaf.spaceOneOrMore(), //
				new RegexLeaf("links"), //
				RegexLeaf.spaceZeroOrMore(), //
				color().getRegex(), //
				RegexLeaf.spaceZeroOrMore(), //
				new RegexLeaf(":"), //
				RegexLeaf.spaceZeroOrMore(), //
				new RegexLeaf(1, "NOTE", "(.*)"), RegexLeaf.end());
	}

	private static ColorParser color() {
		return ColorParser.simpleColor(ColorType.BACK);
	}

	@Override
	@Explain
	protected String explainArg(LineLocation location, RegexResult arg) {
		final StringBuilder sb = new StringBuilder();

		// 'constraint on links : {xor}' draws a constraint between the two
		// last links of the diagram, like the UML xor notation between two
		// associations; executeArg fails when there are fewer than two links.
		sb.append("Drawing the constraint \"").append(arg.get("NOTE", 0))
				.append("\" between the two last links");

		// The color is parsed but never read by executeArg.
		if (arg.get("COLOR", 0) != null)
			sb.append(" (the color ").append(arg.get("COLOR", 0)).append(" is currently ignored)");

		return sb.toString();
	}

	@Override
	protected CommandExecutionResult executeArg(CucaDiagram diagram, LineLocation location, RegexResult arg, ParserPass currentPass)
			throws NoSuchColorException {
		final List<Link> links = diagram.getTwoLastLinks();
		if (links == null) {
			return CommandExecutionResult.error("Cannot put constraint on two last links");
		}
		final BlocLines note = BlocLines.getWithNewlines(arg.get("NOTE", 0));
		return diagram.constraintOnLinks(links.get(0), links.get(1), note.toDisplay());
	}

}