/*
 * Created on 23-Dec-2003
 *
 * To change the template for this generated file go to
 * Window - Preferences - Java - Code Generation - Code and Comments
 */
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 type tokens.
 *
 */
public class PreTypeParser extends AbstractPrerequisiteParser implements
		PrerequisiteParserInterface
{
	/**
	 * 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[]{"TYPE"};
	}

	/**
	 * 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
	{

		int aNum = 1;
		final StringTokenizer aTok = new StringTokenizer(formula, ",");
		String aString = aTok.nextToken();
		try
		{
			aNum = Integer.parseInt(aString);
		}
		catch (NumberFormatException nfe)
		{
			throw new PersistenceLayerException(formula + " must start with a number in PRETYPE");
		}

		// Parse new style syntax
		Prerequisite prereq =
				super.parse(kind, formula, invertResult, overrideQualify);
		prereq.setOperand(Integer.toString(aNum));

		//
		// If only 1 selection, then don't make a PREMULT
		// i.e. PRETYPE:1,typename shouldn't need to be converted to PREMULT:1,[PRETYPE:1,typename]
		//
		if (aTok.countTokens() == 1)
		{
			prereq.setOperator(PrerequisiteOperator.EQ);
			prereq.setKey(aTok.nextToken());
		}
		else
		{
			prereq.setKind(null); // PREMULT
			while (aTok.hasMoreTokens())
			{
				Prerequisite subreq = new Prerequisite();
				subreq.setOperator(PrerequisiteOperator.EQ);
				subreq.setKind("type");
				subreq.setKey(aTok.nextToken());
				prereq.addPrerequisite(subreq);
			}
		}

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