PreStatParser.java

/*
 * PreStatParser.java
 * Copyright 2001 (C) Bryan McRoberts <merton_monk@yahoo.com>
 * Copyright 2003 (C) Chris Ward <frugal@purplewombat.co.uk>
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * Created on November 28, 2003
 *
 * Current Ver: $Revision$
 *
 */
package plugin.pretokens.parser;

import pcgen.core.prereq.Prerequisite;
import pcgen.core.prereq.PrerequisiteOperator;
import pcgen.core.prereq.PrerequisiteException;
import pcgen.persistence.PersistenceLayerException;
import pcgen.persistence.lst.prereq.AbstractPrerequisiteParser;
import pcgen.persistence.lst.prereq.PrerequisiteParserInterface;
import pcgen.util.Logging;

/**
 * A prerequisite parser class that handles the parsing of pre stat tokens.
 *
 */
public class PreStatParser extends AbstractPrerequisiteParser implements
		PrerequisiteParserInterface
{
	/**
	 *
	 */
	public PreStatParser()
	{
		super();
	}

	/**
	 * Get the type of prerequisite handled by this token.
	 * @return the type of prerequisite handled by this token.
	 */
    @Override
	public String[] kindsHandled()
	{
		return new String[]{"STAT", "STATEQ", "STATGT", "STATGTEQ", "STATLT",
			"STATLTEQ", "STATNEQ"};
	}

	/**
	 * Parse the pre req list
	 *
	 * @param kind The kind of the prerequisite (less the "PRE" prefix)
	 * @param formula The body of the prerequisite.
	 * @param invertResult Whether the prerequisite should invert the result.
	 * @param overrideQualify
	 *           if set true, this prerequisite will be enforced in spite
	 *           of any "QUALIFY" tag that may be present.
	 * @return PreReq
	 * @throws PersistenceLayerException
	 */
	@Override
	public Prerequisite parse(String kind,
	                          String formula,
	                          boolean invertResult,
	                          boolean overrideQualify) throws PersistenceLayerException
	{
		Prerequisite prereq = super.parse(kind, formula, invertResult, overrideQualify);
		try
		{
			prereq.setKind(null); // PREMULT

			// Get the comparator type STATGTEQ, STAT, STATNEQ etc.
			String compType = kind.substring(4);

			if (compType.isEmpty())
			{
				compType = "gteq";
			}

			String[] tokens = formula.split(",|\\|");
			int currToken = 0;

			// Get the minimum match count
			String aString = tokens[currToken++];

			try
			{
				prereq.setOperand(Integer.toString(Integer.parseInt(aString)));
			}
			catch (NumberFormatException e)
			{
				Logging
					.errorPrint("Badly formed PRESTAT attribute: " + aString);
				prereq.setOperand("1");
			}

			while (currToken < tokens.length)
			{
				aString = tokens[currToken++];

				final int idxEquals = aString.lastIndexOf('=');
				if (idxEquals < 3)
				{
					throw new PersistenceLayerException("PRE"
						+ kindsHandled()[0] + " formula '" + formula
						+ "' is not valid.");
				}

				final String stat =
						aString.substring(0, Math.min(3, idxEquals));
				Prerequisite statPrereq = new Prerequisite();
				statPrereq.setKind("stat");
				statPrereq.setKey(stat);
				statPrereq.setOperator(compType);
				statPrereq.setOperand(aString.substring(idxEquals + 1));

				prereq.addPrerequisite(statPrereq);
			}

			if ((prereq.getPrerequisiteCount() == 1)
				&& prereq.getOperator().equals(PrerequisiteOperator.GTEQ)
				&& prereq.getOperand().equals("1"))
			{
				prereq = prereq.getPrerequisites().get(0);
			}

			if (invertResult)
			{
				prereq.setOperator(prereq.getOperator().invert());
			}
		}
		catch (PrerequisiteException pe)
		{
			throw new PersistenceLayerException(
				"Unable to parse the prerequisite :'" + kind + ":" + formula
					+ "'. " + pe.getLocalizedMessage());
		}
		return prereq;
	}
}