package org.apache.lucene.index;

/**
 * Copyright 2004 The Apache Software Foundation
 *
 * Licensed 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.
 */

import org.apache.lucene.store.Directory;
import org.apache.lucene.store.InputStream;
import org.apache.lucene.store.OutputStream;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.store.Lock;
import java.util.HashMap;
import java.util.Iterator;
import java.io.IOException;


/**
 * Class for accessing a compound stream.
 * This class implements a directory, but is limited to only read operations.
 * Directory methods that would normally modify data throw an exception.
 *
 * @author Dmitry Serebrennikov
 * @version $Id: CompoundFileReader.java,v 1.5 2004/03/29 22:48:02 cutting Exp $
 */
class CompoundFileReader extends Directory {

    private static final class FileEntry {
        long offset;
        long length;
    }


    // Base info
    private Directory directory;
    private String fileName;

    // Reference count
    private boolean open;

    private InputStream stream;
    private HashMap entries = new HashMap();


    public CompoundFileReader(Directory dir, String name)
    throws IOException
    {
        directory = dir;
        fileName = name;

        boolean success = false;

        try {
            stream = dir.openFile(name);

            // read the directory and init files
            int count = stream.readVInt();
            FileEntry entry = null;
            for (int i=0; i length)
                throw new IOException("read past EOF");
              base.seek(fileOffset + start);
              base.readBytes(b, offset, len);
            }
        }

        /** Expert: implements seek.  Sets current position in this file, where
         *  the next {@link #readInternal(byte[],int,int)} will occur.
         * @see #readInternal(byte[],int,int)
         */
        protected void seekInternal(long pos) throws IOException {}

        /** Closes the stream to futher operations. */
        public void close() throws IOException {}

    }
}