/**

 * 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.

 */

/*

 * @test

 * @summary Test the recording and checking of module hashes

 * @author Andrei Eremeev

 * @library /lib/testlibrary

 * @modules java.base/jdk.internal.module

 *          jdk.jlink/jdk.tools.jlink.internal

 *          jdk.jlink/jdk.tools.jmod

 *          jdk.compiler

 * @build CompilerUtils

 * @run testng HashesTest

 */

import java.io.IOException;

import java.io.InputStream;

import java.lang.module.ModuleDescriptor;

import java.lang.module.ModuleFinder;

import java.lang.module.ModuleReader;

import java.lang.module.ModuleReference;

import java.lang.reflect.Method;

import java.nio.file.FileVisitResult;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.nio.file.SimpleFileVisitor;

import java.nio.file.attribute.BasicFileAttributes;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Collections;

import java.util.List;

import java.util.Optional;

import java.util.Set;

import java.util.stream.Collectors;

import jdk.internal.module.ConfigurableModuleFinder;

import jdk.internal.module.ModuleHashes;

import org.testng.annotations.BeforeTest;

import org.testng.annotations.Test;

import static org.testng.Assert.*;

public class HashesTest {

    private final Path testSrc = Paths.get(System.getProperty("test.src"));

    private final Path modSrc = testSrc.resolve("src");

    private final Path mods = Paths.get("mods");

    private final Path jmods = Paths.get("jmods");

    private final String[] modules = new String[] { "m1", "m2", "m3"};

    private static Method hashesMethod;

    @BeforeTest

    private void setup() throws Exception {

        if (Files.exists(jmods)) {

            deleteDirectory(jmods);

        }

        Files.createDirectories(jmods);

        // build m2, m3 required by m1

        compileModule("m2", modSrc);

        jmod("m2");

        compileModule("m3", modSrc);

        jmod("m3");

        // build m1

        compileModule("m1", modSrc);

        // no hash is recorded since m1 has outgoing edges

        // compile org.bar and org.foo

        compileModule("org.bar", modSrc);

        compileModule("org.foo", modSrc);

        try {

            hashesMethod = ModuleDescriptor.class.getDeclaredMethod("hashes");

            hashesMethod.setAccessible(true);

        } catch (ReflectiveOperationException x) {

            throw new InternalError(x);

        }

    }

    @Test

    public void test() throws Exception {

        for (String mn : modules) {

            assertFalse(hashes(mn).isPresent());

        }

        // hash m1 in m2

        checkHashes(hashes("m2").get(), "m1");

        // hash m1 in m2

        checkHashes(hashes("m2").get(), "m1");

        // create m2.jmod with no hash

        jmod("m2");

        // run jmod hash command to hash m1 in m2 and m3

                "--hash-modules", ".*"));

        checkHashes(hashes("m2").get(), "m1");

        checkHashes(hashes("m3").get(), "m1");

        jmod("org.bar");

        jmod("org.foo");

        checkHashes(hashes("org.bar").get(), "org.foo");

        checkHashes(hashes("m3").get(), "org.foo", "org.bar", "m1");

    }

    private void checkHashes(ModuleHashes hashes, String... hashModules) {

        assertTrue(hashes.names().equals(Set.of(hashModules)));

    }

    private Optional<ModuleHashes> hashes(String name) throws Exception {

        ModuleFinder finder = ModuleFinder.of(jmods.resolve(name + ".jmod"));

        if (finder instanceof ConfigurableModuleFinder) {

            ((ConfigurableModuleFinder) finder)

                .configurePhase(ConfigurableModuleFinder.Phase.LINK_TIME);

        }

        ModuleReference mref = finder.find(name).orElseThrow(RuntimeException::new);

        ModuleReader reader = mref.open();

        try (InputStream in = reader.open("module-info.class").get()) {

            ModuleDescriptor md = ModuleDescriptor.read(in);

            Optional<ModuleHashes> hashes =

                (Optional<ModuleHashes>) hashesMethod.invoke(md);

            System.out.format("hashes in module %s %s%n", name,

                              hashes.isPresent() ? "present" : "absent");

            if (hashes.isPresent()) {

                hashes.get().names().stream()

                    .sorted()

                    .forEach(n -> System.out.format("  %s %s%n", n, hashes.get().hashFor(n)));

            }

            return hashes;

        } finally {

            reader.close();

        }

    }

    private void deleteDirectory(Path dir) throws IOException {

        Files.walkFileTree(dir, new SimpleFileVisitor<Path>() {

            @Override

            public FileVisitResult visitFile(Path file, BasicFileAttributes attrs)

                throws IOException

            {

                Files.delete(file);

                return FileVisitResult.CONTINUE;

            }

            @Override

            public FileVisitResult postVisitDirectory(Path dir, IOException exc)

                throws IOException

            {

                Files.delete(dir);

                return FileVisitResult.CONTINUE;

            }

        });

    }

    private void compileModule(String moduleName, Path src) throws IOException {

        Path msrc = src.resolve(moduleName);

    }

    private void jmod(String moduleName, String... options) throws IOException {

        Path mclasses = mods.resolve(moduleName);

        Path outfile = jmods.resolve(moduleName + ".jmod");

        List<String> args = new ArrayList<>();

        args.add("create");

        Collections.addAll(args, options);

        Collections.addAll(args, "--class-path", mclasses.toString(),

                           outfile.toString());

        if (Files.exists(outfile))

            Files.delete(outfile);

        runJmod(args);

    }

    private void runJmod(List<String> args) {

        int rc = jdk.tools.jmod.Main.run(args.toArray(new String[args.size()]), System.out);

        System.out.println("jmod options: " + args.stream().collect(Collectors.joining(" ")));

        if (rc != 0) {

            throw new AssertionError("Jmod failed: rc = " + rc);

        }

    }

}