/*

 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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 General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

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 */

package build.tools.jigsaw;

import java.io.ByteArrayOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.lang.module.ModuleFinder;

import java.lang.module.ModuleReference;

import java.nio.file.DirectoryStream;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.util.Optional;

import java.util.Set;

import jdk.internal.module.ModuleInfoExtender;

/**

 * Adds the Packages class file attribute to each module-info.class in an

 * exploded build.

 */

public class AddPackagesAttribute {

    public static void main(String[] args) throws IOException {

        if (args.length != 1) {

            System.err.println("Usage AddPackagesAttribute exploded-java-home");

            System.exit(-1);

        }

        String home = args[0];

        Path dir = Paths.get(home, "modules");

        ModuleFinder finder = ModuleFinder.of(dir);

        try (DirectoryStream<Path> stream = Files.newDirectoryStream(dir)) {

            for (Path entry : stream) {

                Path mi = entry.resolve("module-info.class");

                if (Files.isRegularFile(mi)) {

                    String mn = entry.getFileName().toString();

                    Optional<ModuleReference> omref = finder.find(mn);

                    if (omref.isPresent()) {

                        Set<String> packages = omref.get().descriptor().packages();

                        addPackagesAttribute(mi, packages);

                    }

                }

            }

        }

    }

    static void addPackagesAttribute(Path mi, Set<String> packages) throws IOException {

        byte[] bytes;

        try (InputStream in = Files.newInputStream(mi)) {

            ModuleInfoExtender extender = ModuleInfoExtender.newExtender(in);

            extender.packages(packages);

            ByteArrayOutputStream baos = new ByteArrayOutputStream();

            extender.write(baos);

            bytes = baos.toByteArray();

        }

        Files.write(mi, bytes);

    }

}