/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
 * indicated by the @author tags or express copyright attribution
 * statements applied by the authors.  All third-party contributions are
 * distributed under license by Red Hat Middleware LLC.
 *
 * This copyrighted material is made available to anyone wishing to use, modify,
 * copy, or redistribute it subject to the terms and conditions of the GNU
 * Lesser General Public License, as published by the Free Software Foundation.
 *
 * This program 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 distribution; if not, write to:
 * Free Software Foundation, Inc.
 * 51 Franklin Street, Fifth Floor
 * Boston, MA  02110-1301  USA
 *
 */
package org.hibernate.hql.internal.ast;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.hibernate.QueryException;
import org.hibernate.internal.CoreMessageLogger;

import org.jboss.logging.Logger;

import antlr.RecognitionException;

An error handler that counts parsing errors and warnings.
/**
 * An error handler that counts parsing errors and warnings.
 */
public class ErrorCounter implements ParseErrorHandler {
	private static final CoreMessageLogger LOG = Logger.getMessageLogger(
			CoreMessageLogger.class,
			ErrorCounter.class.getName()
	);

	private final String hql;

	private List<String> errorList = new ArrayList<String>();
	private List<RecognitionException> recognitionExceptions = new ArrayList<RecognitionException>();

	
Constructs an ErrorCounter without knowledge of the HQL, meaning that generated QueryException
instances *will not* contain the HQL (and will need to be wrapped at a higher level in another
QueryException).
/**
	 * Constructs an ErrorCounter without knowledge of the HQL, meaning that generated QueryException
	 * instances *will not* contain the HQL (and will need to be wrapped at a higher level in another
	 * QueryException).
	 */
	public ErrorCounter() {
		this( null );
	}

	
Constructs an ErrorCounter with knowledge of the HQL, meaning that generated QueryException
instances *will* contain the HQL.
/**
	 * Constructs an ErrorCounter with knowledge of the HQL, meaning that generated QueryException
	 * instances *will* contain the HQL.
	 */
	public ErrorCounter(String hql) {
		this.hql = hql;
	}

	@Override
	public void reportError(RecognitionException e) {
		reportError( e.toString() );
		recognitionExceptions.add( e );
		LOG.error( e.toString(), e );
	}

	@Override
	public void reportError(String message) {
		LOG.error( message );
		errorList.add( message );
	}

	@Override
	public int getErrorCount() {
		return errorList.size();
	}

	@Override
	public void reportWarning(String message) {
		LOG.debug( message );
	}

	private String getErrorString() {
		final StringBuilder buf = new StringBuilder();
		final Iterator<String> iterator = errorList.iterator();
		while ( iterator.hasNext() ) {
			buf.append( iterator.next() );
			if ( iterator.hasNext() ) {
				buf.append( "\n" );
			}

		}
		return buf.toString();
	}

	@Override
	public void throwQueryException() throws QueryException {
		if ( getErrorCount() > 0 ) {
		if ( recognitionExceptions.size() > 0 ) {
				throw QuerySyntaxException.convert( recognitionExceptions.get( 0 ), hql );
		}
			throw new QueryException( getErrorString(), hql );
		}
		LOG.debug( "throwQueryException() : no errors" );
	}
}