/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.exoplatform.services.jcr.impl.core.query.lucene;

import java.io.IOException;

import org.apache.lucene.analysis.Token;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.index.Payload;

/**
 * <code>SingletonTokenStream</code> implements a token stream that wraps a
 * single value with a given property type. The property type is stored as a
 * payload on the single returned token.
 */
public final class SingletonTokenStream extends TokenStream {

    /**
     * The string value of the token.
     */
    private String value;

    /**
     * The payload of the token.
     */
    private final Payload payload;

    /**
     * Creates a new SingleTokenStream with the given value and a property
     * <code>type</code>.
     *
     * @param value the string value that will be returned with the token.
     * @param type the JCR property type.
     */
    public SingletonTokenStream(String value, int type) {
        this.value = value;
        this.payload = new Payload(new PropertyMetaData(type).toByteArray());
    }

    /**
     * Creates a new SingleTokenStream with the given token.
     *
     * @param t the token.
     */
    public SingletonTokenStream(Token t) {
        this.value = t.term();
        this.payload = t.getPayload();
    }

    /**
     * {@inheritDoc}
     */
    public Token next(Token reusableToken) throws IOException {
        if (value == null) {
            return null;
        }
        reusableToken.clear();
        reusableToken.setTermBuffer(value);
        reusableToken.setPayload(payload);
        reusableToken.setStartOffset(0);
        reusableToken.setEndOffset(value.length());
        value = null;
        return reusableToken;
    }
}
