/*
 * Copyright 2010-2015 The plexus developers.
 *
 * 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.
 */
package org.codehaus.plexus.archiver.tar;

import javax.inject.Named;

import java.io.Closeable;
import java.io.File;
import java.io.IOException;
import java.util.Enumeration;
import java.util.Iterator;

import org.apache.commons.compress.archivers.ArchiveEntry;
import org.apache.commons.compress.archivers.tar.TarArchiveEntry;
import org.codehaus.plexus.components.io.resources.AbstractPlexusIoArchiveResourceCollection;
import org.codehaus.plexus.components.io.resources.PlexusIoResource;

@Named("tar")
public class PlexusIoTarFileResourceCollection extends AbstractPlexusIoArchiveResourceCollection implements Closeable {

    protected TarFile newTarFile(File file) {
        return new TarFile(file);
    }

    TarFile tarFile = null;

    @Override
    public void close() throws IOException {
        if (tarFile != null) {
            tarFile.close();
        }
    }

    @Override
    public boolean isConcurrentAccessSupported() {
        return false;
    }

    @Override
    protected Iterator<PlexusIoResource> getEntries() throws IOException {
        final File f = getFile();
        if (f == null) {
            throw new IOException("The tar archive file has not been set.");
        }
        if (tarFile == null) {
            tarFile = newTarFile(f);
        }
        final Enumeration<ArchiveEntry> en = tarFile.getEntries();
        return new Iterator<PlexusIoResource>() {

            @Override
            public boolean hasNext() {
                return en.hasMoreElements();
            }

            @Override
            public PlexusIoResource next() {
                final TarArchiveEntry entry = (TarArchiveEntry) en.nextElement();
                return entry.isSymbolicLink()
                        ? new TarSymlinkResource(tarFile, entry)
                        : new TarResource(tarFile, entry);
            }

            @Override
            public void remove() {
                throw new UnsupportedOperationException("Removing isn't implemented.");
            }
        };
    }
}
