PrePCLevelParser.java

/*
 * PrePCLevelParser.java
 *
 * 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 2007-12-07
 *
 */
package plugin.pretokens.parser;

import java.util.StringTokenizer;

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

/**
 * A prerequisite parser class that handles the parsing of pre PC Level tokens.
 *
 */
public class PrePCLevelParser extends AbstractPrerequisiteParser implements
        PrerequisiteParserInterface
{
	
	//TODO created tests
	//TODO create writer
	//TODO create prereqparser

	/**
	 * 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[]
		{ "PCLEVEL" };
	}

	/**
	 * 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);

		if (formula.contains("MIN") || formula.contains("MAX"))
		{
			StringTokenizer tok = new StringTokenizer(formula, ",");
			Prerequisite maxPrereq = new Prerequisite();
			Prerequisite minPrereq = new Prerequisite();
			boolean hasMin = false;
			boolean hasMax = false;
			while (tok.hasMoreTokens())
			{
				String value = tok.nextToken();
				String[] vals = value.split("=");
				if (vals.length != 2)
				{
					throw new PersistenceLayerException(
						"PREPCLEVEL must be either 'MIN=x', 'MAX=y' or "
							+ "'MIN=x,MAX=y' where 'x' and 'y' are integers. '"
							+ formula + "' is not valid. ");

				}
				String token = vals[0];
				String hdVal = vals[1];
				try
				{
					Integer.parseInt(hdVal);
				}
				catch (NumberFormatException nfe)
				{
					throw new PersistenceLayerException(
						"PREPCLEVEL must be either 'MIN=x', 'MAX=y' or "
							+ "'MIN=x,MAX=y' where 'x' and 'y' are integers. '"
							+ formula
							+ "' is not valid: "
							+ hdVal
							+ " is not an integer");
				}
				if (token.equals("MIN"))
				{
					minPrereq.setKind("pclevel");
					minPrereq.setOperator(PrerequisiteOperator.GTEQ);
					minPrereq.setOperand(hdVal);

					hasMin = true;

				}
				if (token.equals("MAX"))
				{
					maxPrereq.setKind("pclevel");
					maxPrereq.setOperator(PrerequisiteOperator.LTEQ);
					maxPrereq.setOperand(hdVal);
					hasMax = true;
				}
			}
			if (hasMin && hasMax)
			{
				prereq.setKind(null); // PREMULT
				prereq.setOperand("2");
				prereq.addPrerequisite(minPrereq);
				prereq.addPrerequisite(maxPrereq);
			}
			else if (hasMin)
			{
				prereq = minPrereq;
			}
			else if (hasMax)
			{
				prereq = maxPrereq;
			}

		}
		if (invertResult)
		{
			prereq.setOperator(prereq.getOperator().invert());
		}
		return prereq;
	}
}