/*

 * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 *   - Redistributions of source code must retain the above copyright

 *     notice, this list of conditions and the following disclaimer.

 *

 *   - Redistributions in binary form must reproduce the above copyright

 *     notice, this list of conditions and the following disclaimer in the

 *     documentation and/or other materials provided with the distribution.

 *

 *   - Neither the name of Oracle nor the names of its

 *     contributors may be used to endorse or promote products derived

 *     from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS

 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,

 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

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 */

package com.sun.nio.zipfs;

import java.nio.file.DirectoryStream;

import java.nio.file.ClosedDirectoryStreamException;

import java.nio.file.NotDirectoryException;

import java.nio.file.Path;

import java.util.Iterator;

import java.util.NoSuchElementException;

import java.io.IOException;

import static com.sun.nio.zipfs.ZipUtils.*;

/**

 *

 * @author  Xueming Shen, Rajendra Gutupalli, Jaya Hangal

 */

public class ZipDirectoryStream implements DirectoryStream<Path> {

    private final ZipFileSystem zipfs;

    private final byte[] path;

    private final DirectoryStream.Filter<? super Path> filter;

    private volatile boolean isClosed;

    private volatile Iterator<Path> itr;

    ZipDirectoryStream(ZipPath zipPath,

                       DirectoryStream.Filter<? super java.nio.file.Path> filter)

        throws IOException

    {

        this.zipfs = zipPath.getFileSystem();

        this.path = zipPath.getResolvedPath();

        this.filter = filter;

        // sanity check

        if (!zipfs.isDirectory(path))

            throw new NotDirectoryException(zipPath.toString());

    }

    @Override

    public synchronized Iterator<Path> iterator() {

        if (isClosed)

            throw new ClosedDirectoryStreamException();

        if (itr != null)

            throw new IllegalStateException("Iterator has already been returned");

        try {

            itr = zipfs.iteratorOf(path, filter);

        } catch (IOException e) {

            throw new IllegalStateException(e);

        }

        return new Iterator<Path>() {

            private Path next;

            @Override

            public boolean hasNext() {

                if (isClosed)

                    return false;

                return itr.hasNext();

            }

            @Override

            public synchronized Path next() {

                if (isClosed)

                    throw new NoSuchElementException();

                return itr.next();

            }

            @Override

            public void remove() {

                throw new UnsupportedOperationException();

            }

        };

    }

    @Override

    public synchronized void close() throws IOException {

        isClosed = true;

    }

}