/*

 * Copyright (c) 2019, 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.

 *

 * 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

 * questions.

 */

import jdk.internal.module.ModuleInfoWriter;

import java.io.File;

import java.io.IOException;

import java.io.OutputStream;

import java.lang.module.ModuleDescriptor;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.util.ArrayList;

import java.util.List;

import java.util.jar.JarEntry;

import java.util.jar.JarOutputStream;

import java.util.stream.Stream;

/*

 * Launches a new Java process with a main class packed inside a module.

 */

public class TestProcessModuleLauncher extends TestProcessLauncher {

    private static final Path TEST_MODULES = USER_DIR.resolve("testmodules");

    private static final String MODULE_NAME = "module1";

    public TestProcessModuleLauncher(String className) {

        super(className);

    }

    protected String prepareLaunch(String javaExec, String pipePort) {

        try {

            prepareModule();

            return javaExec + " --module-path " + TEST_MODULES.toFile().getAbsolutePath() +

                    " -m " + MODULE_NAME + "/" + className + " -pipe.port=" + pipePort;

        } catch (IOException e) {

            throw new RuntimeException("Failed to prepare a jar file", e);

        }

    }

    private void prepareModule() throws IOException {

        TEST_MODULES.toFile().mkdirs();

        Path moduleJar = TEST_MODULES.resolve("mod1.jar");

        ModuleDescriptor md = createModuleDescriptor();

        createModuleJarFile(moduleJar, md, TEST_CLASSES_DIR, Paths.get("."));

    }

    private ModuleDescriptor createModuleDescriptor() {

        ModuleDescriptor.Builder builder

                = ModuleDescriptor.newModule(MODULE_NAME).requires("java.base");

        return builder.build();

    }

    private static void createModuleJarFile(Path jarfile, ModuleDescriptor md, Path dir, Path... files)

            throws IOException {

        Path parent = jarfile.getParent();

        if (parent != null) {

            Files.createDirectories(parent);

        }

        List<Path> entries = findAllRegularFiles(dir, files);

        try (OutputStream out = Files.newOutputStream(jarfile);

             JarOutputStream jos = new JarOutputStream(out)) {

            if (md != null) {

                JarEntry je = new JarEntry("module-info.class");

                jos.putNextEntry(je);

                ModuleInfoWriter.write(md, jos);

                jos.closeEntry();

            }

            for (Path entry : entries) {

                String name = toJarEntryName(entry);

                jos.putNextEntry(new JarEntry(name));

                Files.copy(dir.resolve(entry), jos);

                jos.closeEntry();

            }

        }

    }

    private static String toJarEntryName(Path file) {

        Path normalized = file.normalize();

        return normalized.subpath(0, normalized.getNameCount())

                .toString()

                .replace(File.separatorChar, '/');

    }

    private static List<Path> findAllRegularFiles(Path dir, Path[] files) throws IOException {

        List<Path> entries = new ArrayList<>();

        for (Path file : files) {

            try (Stream<Path> stream = Files.find(dir.resolve(file), Integer.MAX_VALUE,

                    (p, attrs) -> attrs.isRegularFile() && !p.getParent().equals(dir.resolve(".")))) {

                stream.map(dir::relativize)

                        .forEach(entries::add);

            }

        }

        return entries;

    }

    public String getModuleName() {

        return MODULE_NAME;

    }

}