/*
 * $Id$
 *
 * Copyright (C) 2003-2015 JNode.org
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 *
 * This library is 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 Lesser General Public 
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser 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.
 */
 
package org.jnode.shell.syntax;

import org.jnode.nanoxml.XMLElement;


/**
 * An ArgumentSyntax instance allows an Argument to appear exactly once.
 * 
 * @author crawley@jnode.org
 *
 */
public class ArgumentSyntax extends Syntax {

    private final String argName;
    private final String flags;
    
    public ArgumentSyntax(String label, String argName, String flags, String description) {
        super(label, description);
        this.argName = argName;
        this.flags = flags;
        if (argName.length() == 0) {
            throw new IllegalArgumentException("empty argName");
        }
    }

    public ArgumentSyntax(String label, String argName) {
        this(label, argName, null, null);
    }

    public ArgumentSyntax(String argName) {
        this(null, argName, null, null);
    }

    @Override
    public String format(ArgumentBundle bundle) {
        try {
            Argument<?> arg = bundle.getArgument(this);
            return "<" + arg.formatForUsage() + ">";
        } catch (SyntaxFailureException ex) {
            return "<" + label + "> (Unmatched syntax label!)";
        }
    }

    @Override
    public String toString() {
        return "ArgumentSyntax{" + super.toString() + ",argName=" + 
                argName + ",flags=" + flags + "}";
    }

    @Override
    public MuSyntax prepare(ArgumentBundle bundle) {
        int flags;
        if (this.flags == null || this.flags.length() == 0) {
            flags = 0;
        } else {
            flags = bundle.getArgument(argName).namesToFlags(this.flags);
        }
        return new MuArgument(label, argName, flags);
    }

    public String getArgName() {
        return argName;
    }

    @Override
    public XMLElement toXML() {
        XMLElement element = basicElement("argument");
        element.setAttribute("argLabel", argName);
        return element;
    }
}