/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2013, Red Hat Inc. 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 Inc.
 *
 * 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.jpa.boot.archive.internal;

import java.io.IOException;
import java.net.URL;
import java.util.jar.JarEntry;
import java.util.jar.JarInputStream;
import java.util.zip.ZipEntry;

import org.hibernate.jpa.boot.archive.spi.AbstractArchiveDescriptor;
import org.hibernate.jpa.boot.archive.spi.ArchiveContext;
import org.hibernate.jpa.boot.archive.spi.ArchiveDescriptorFactory;
import org.hibernate.jpa.boot.archive.spi.ArchiveEntry;
import org.hibernate.jpa.boot.archive.spi.ArchiveException;
import org.hibernate.jpa.boot.spi.InputStreamAccess;
import org.hibernate.jpa.internal.EntityManagerMessageLogger;

import org.jboss.logging.Logger;

An ArchiveDescriptor implementation that works on archives accessible through a JarInputStream. NOTE : This is less efficient implementation than JarFileBasedArchiveDescriptor 
Author:
Emmanuel Bernard, Steve Ebersole/**
 * An ArchiveDescriptor implementation that works on archives accessible through a {@link java.util.jar.JarInputStream}.
 * NOTE : This is less efficient implementation than {@link JarFileBasedArchiveDescriptor}
 *
 * @author Emmanuel Bernard
 * @author Steve Ebersole
 */
public class JarInputStreamBasedArchiveDescriptor extends AbstractArchiveDescriptor {
	private static final EntityManagerMessageLogger LOG = Logger.getMessageLogger(
			EntityManagerMessageLogger.class,
			JarInputStreamBasedArchiveDescriptor.class.getName()
	);

	
Constructs a JarInputStreamBasedArchiveDescriptor
Params:
archiveDescriptorFactory – The factory creating this
url – The url to the JAR file
entry – The prefix for entries within the JAR url/**
	 * Constructs a JarInputStreamBasedArchiveDescriptor
	 *
	 * @param archiveDescriptorFactory The factory creating this
	 * @param url The url to the JAR file
	 * @param entry The prefix for entries within the JAR url
	 */
	public JarInputStreamBasedArchiveDescriptor(
			ArchiveDescriptorFactory archiveDescriptorFactory,
			URL url,
			String entry) {
		super( archiveDescriptorFactory, url, entry );
	}

	@Override
	public void visitArchive(ArchiveContext context) {
		final JarInputStream jarInputStream;
		try {
			jarInputStream = new JarInputStream( getArchiveUrl().openStream() );
		}
		catch (Exception e) {
			//really should catch IOException but Eclipse is buggy and raise NPE...
			LOG.unableToFindFile( getArchiveUrl(), e );
			return;
		}

		try {
			JarEntry jarEntry;
			while ( ( jarEntry = jarInputStream.getNextJarEntry() ) != null ) {
				final String jarEntryName = jarEntry.getName();
				if ( getEntryBasePrefix() != null && ! jarEntryName.startsWith( getEntryBasePrefix() ) ) {
					continue;
				}

				if ( jarEntry.isDirectory() ) {
					continue;
				}

				if ( jarEntryName.equals( getEntryBasePrefix() ) ) {
					// exact match, might be a nested jar entry (ie from jar:file:..../foo.ear!/bar.jar)
					//
					// This algorithm assumes that the zipped file is only the URL root (including entry), not
					// just any random entry
					try {
						final JarInputStream subJarInputStream = new JarInputStream( jarInputStream );
						try {
							ZipEntry subZipEntry = jarInputStream.getNextEntry();
							while (subZipEntry != null) {
								if ( ! subZipEntry.isDirectory() ) {
									final String subName = extractName( subZipEntry );
									final InputStreamAccess inputStreamAccess
											= buildByteBasedInputStreamAccess( subName, subJarInputStream );

									final ArchiveEntry entry = new ArchiveEntry() {
										@Override
										public String getName() {
											return subName;
										}

										@Override
										public String getNameWithinArchive() {
											return subName;
										}

										@Override
										public InputStreamAccess getStreamAccess() {
											return inputStreamAccess;
										}
									};

									context.obtainArchiveEntryHandler( entry ).handleEntry( entry, context );
								}
								subZipEntry = jarInputStream.getNextJarEntry();
							}
						}
						finally {
							subJarInputStream.close();
						}
					}
					catch (Exception e) {
						throw new ArchiveException( "Error accessing nested jar", e );
					}
				}
				else {
					final String entryName = extractName( jarEntry );
					final InputStreamAccess inputStreamAccess
							= buildByteBasedInputStreamAccess( entryName, jarInputStream );

					final String relativeName = extractRelativeName( jarEntry );

					final ArchiveEntry entry = new ArchiveEntry() {
						@Override
						public String getName() {
							return entryName;
						}

						@Override
						public String getNameWithinArchive() {
							return relativeName;
						}

						@Override
						public InputStreamAccess getStreamAccess() {
							return inputStreamAccess;
						}
					};

					context.obtainArchiveEntryHandler( entry ).handleEntry( entry, context );
				}
			}

			jarInputStream.close();
		}
		catch (IOException ioe) {
			throw new ArchiveException(
					String.format( "Error accessing JarInputStream [%s]", getArchiveUrl() ),
					ioe
			);
		}
	}
}