/*

 * Copyright (c) 2012, 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.  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

 * questions.

 */

import java.io.*;

import java.nio.file.FileVisitResult;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.SimpleFileVisitor;

import java.nio.file.attribute.BasicFileAttributes;

import java.nio.file.attribute.PosixFilePermission;

import java.nio.file.attribute.PosixFilePermissions;

import java.text.MessageFormat;

import java.util.*;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

import java.util.stream.Collectors;

import java.util.stream.Stream;

public class LinuxDebBundler extends LinuxPackageBundler {

    // Debian rules for package naming are used here

    // https://www.debian.org/doc/debian-policy/ch-controlfields.html#s-f-Source

    //

    // Package names must consist only of lower case letters (a-z),

    // digits (0-9), plus (+) and minus (-) signs, and periods (.).

    // They must be at least two characters long and

    // must start with an alphanumeric character.

    //

    private static final Pattern DEB_PACKAGE_NAME_PATTERN =

            Pattern.compile("^[a-z][a-z\\d\\+\\-\\.]+");

    private static final BundlerParamInfo<String> PACKAGE_NAME =

            new StandardBundlerParam<> (

            Arguments.CLIOptions.LINUX_BUNDLE_NAME.getId(),

            String.class,

            params -> {

                String nm = APP_NAME.fetchFrom(params);

                if (nm == null) return null;

                // make sure to lower case and spaces/underscores become dashes

                nm = nm.toLowerCase().replaceAll("[ _]", "-");

                return nm;

            },

            (s, p) -> {

                if (!DEB_PACKAGE_NAME_PATTERN.matcher(s).matches()) {

                    throw new IllegalArgumentException(new ConfigException(

                            MessageFormat.format(I18N.getString(

                            "error.invalid-value-for-package-name"), s),

                            I18N.getString(

                            "error.invalid-value-for-package-name.advice")));

                }

                return s;

            });

    private final static String TOOL_DPKG_DEB = "dpkg-deb";

    private final static String TOOL_DPKG = "dpkg";

    private final static String TOOL_FAKEROOT = "fakeroot";

    private final static String DEB_ARCH;

    static {

        String debArch;

        try {

            debArch = Executor.of(TOOL_DPKG, "--print-architecture").saveOutput(

                    true).executeExpectSuccess().getOutput().get(0);

        } catch (IOException ex) {

            debArch = null;

        }

        DEB_ARCH = debArch;

    }

    private static final BundlerParamInfo<String> FULL_PACKAGE_NAME =

            new StandardBundlerParam<>(

                    "linux.deb.fullPackageName", String.class, params -> {

                        return PACKAGE_NAME.fetchFrom(params)

                            + "_" + VERSION.fetchFrom(params)

                            + "-" + RELEASE.fetchFrom(params)

                            + "_" + DEB_ARCH;

                    }, (s, p) -> s);

    private static final BundlerParamInfo<String> EMAIL =

            new StandardBundlerParam<> (

            Arguments.CLIOptions.LINUX_DEB_MAINTAINER.getId(),

            String.class,

            params -> "Unknown",

            (s, p) -> s);

    private static final BundlerParamInfo<String> MAINTAINER =

            new StandardBundlerParam<> (

            BundleParams.PARAM_MAINTAINER,

            String.class,

            params -> VENDOR.fetchFrom(params) + " <"

                    + EMAIL.fetchFrom(params) + ">",

            (s, p) -> s);

    private static final BundlerParamInfo<String> SECTION =

            new StandardBundlerParam<>(

            Arguments.CLIOptions.LINUX_CATEGORY.getId(),

            String.class,

            params -> "misc",

            (s, p) -> s);

    private static final BundlerParamInfo<String> LICENSE_TEXT =

            new StandardBundlerParam<> (

            "linux.deb.licenseText",

            String.class,

            params -> {

                try {

                    String licenseFile = LICENSE_FILE.fetchFrom(params);

                    if (licenseFile != null) {

                        return Files.readString(Path.of(licenseFile));

                    }

                } catch (IOException e) {

                    Log.verbose(e);

                }

                return "Unknown";

            },

            (s, p) -> s);

    public LinuxDebBundler() {

        super(PACKAGE_NAME);

    }

    @Override

    public void doValidate(Map<String, ? super Object> params)

            throws ConfigException {

        // Show warning if license file is missing

        if (LICENSE_FILE.fetchFrom(params) == null) {

            Log.verbose(I18N.getString("message.debs-like-licenses"));

        }

    }

    @Override

    protected List<ToolValidator> getToolValidators(

            Map<String, ? super Object> params) {

        return Stream.of(TOOL_DPKG_DEB, TOOL_DPKG, TOOL_FAKEROOT).map(

                ToolValidator::new).collect(Collectors.toList());

    }

    @Override

    protected File buildPackageBundle(

            Map<String, String> replacementData,

            Map<String, ? super Object> params, File outputParentDir) throws

            PackagerException, IOException {

        prepareProjectConfig(replacementData, params);

        adjustPermissionsRecursive(createMetaPackage(params).sourceRoot().toFile());

        return buildDeb(params, outputParentDir);

    }

    private static final Pattern PACKAGE_NAME_REGEX = Pattern.compile("^(^\\S+):");

    @Override

    protected void initLibProvidersLookup(

            Map<String, ? super Object> params,

            LibProvidersLookup libProvidersLookup) {

        //

        // `dpkg -S` command does glob pattern lookup. If not the absolute path

        // to the file is specified it might return mltiple package names.

        // Even for full paths multiple package names can be returned as

        // it is OK for multiple packages to provide the same file. `/opt`

        // directory is such an example. So we have to deal with multiple

        // packages per file situation.

        //

        // E.g.: `dpkg -S libc.so.6` command reports three packages:

        // libc6-x32: /libx32/libc.so.6

        // libc6:amd64: /lib/x86_64-linux-gnu/libc.so.6

        // libc6-i386: /lib32/libc.so.6

        // `:amd64` is architecture suffix and can (should) be dropped.

        // Still need to decide what package to choose from three.

        // libc6-x32 and libc6-i386 both depend on libc6:

        // $ dpkg -s libc6-x32

        // Package: libc6-x32

        // Status: install ok installed

        // Priority: optional

        // Section: libs

        // Installed-Size: 10840

        // Maintainer: Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com>

        // Architecture: amd64

        // Source: glibc

        // Version: 2.23-0ubuntu10

        // Depends: libc6 (= 2.23-0ubuntu10)

        //

        // We can dive into tracking dependencies, but this would be overly

        // complicated.

        //

        // For simplicity lets consider the following rules:

        // 1. If there is one item in `dpkg -S` output, accept it.

        // 2. If there are multiple items in `dpkg -S` output and there is at

        //  least one item with the default arch suffix (DEB_ARCH),

        //  accept only these items.

        // 3. If there are multiple items in `dpkg -S` output and there are

        //  no with the default arch suffix (DEB_ARCH), accept all items.

        // So lets use this heuristics: don't accept packages for whom

        //  `dpkg -p` command fails.

        // 4. Arch suffix should be stripped from accepted package names.

        //

        libProvidersLookup.setPackageLookup(file -> {

            Set<String> archPackages = new HashSet<>();

            Set<String> otherPackages = new HashSet<>();

            Executor.of(TOOL_DPKG, "-S", file.toString())

                    .saveOutput(true).executeExpectSuccess()

                    .getOutput().forEach(line -> {

                        Matcher matcher = PACKAGE_NAME_REGEX.matcher(line);

                        if (matcher.find()) {

                            String name = matcher.group(1);

                            if (name.endsWith(":" + DEB_ARCH)) {

                                // Strip arch suffix

                                name = name.substring(0,

                                        name.length() - (DEB_ARCH.length() + 1));

                                archPackages.add(name);

                            } else {

                                otherPackages.add(name);

                            }

                        }

                    });

            if (!archPackages.isEmpty()) {

                return archPackages.stream();

            }

            return otherPackages.stream();

        });

    }

    @Override

    protected List<ConfigException> verifyOutputBundle(

            Map<String, ? super Object> params, Path packageBundle) {

        List<ConfigException> errors = new ArrayList<>();

        String controlFileName = "control";

        List<PackageProperty> properties = List.of(

                new PackageProperty("Package", PACKAGE_NAME.fetchFrom(params),

                        "APPLICATION_PACKAGE", controlFileName),

                new PackageProperty("Version", String.format("%s-%s",

                        VERSION.fetchFrom(params), RELEASE.fetchFrom(params)),

                        "APPLICATION_VERSION-APPLICATION_RELEASE",

                        controlFileName),

                new PackageProperty("Architecture", DEB_ARCH, "APPLICATION_ARCH",

                        controlFileName));

        List<String> cmdline = new ArrayList<>(List.of(TOOL_DPKG_DEB, "-f",

                packageBundle.toString()));

        properties.forEach(property -> cmdline.add(property.name));

        try {

            Map<String, String> actualValues = Executor.of(cmdline.toArray(String[]::new))

                    .saveOutput(true)

                    .executeExpectSuccess()

                    .getOutput().stream()

                            .map(line -> line.split(":\\s+", 2))

                            .collect(Collectors.toMap(

                                    components -> components[0],

                                    components -> components[1]));

            properties.forEach(property -> errors.add(property.verifyValue(

                    actualValues.get(property.name))));

        } catch (IOException ex) {

            // Ignore error as it is not critical. Just report it.

            Log.verbose(ex);

        }

        return errors;

    }

    /*

     * set permissions with a string like "rwxr-xr-x"

     *

     * This cannot be directly backport to 22u which is built with 1.6

     */

    private void setPermissions(File file, String permissions) {

        Set<PosixFilePermission> filePermissions =

                PosixFilePermissions.fromString(permissions);

        try {

            if (file.exists()) {

                Files.setPosixFilePermissions(file.toPath(), filePermissions);

            }

        } catch (IOException ex) {

            Log.error(ex.getMessage());

            Log.verbose(ex);

        }

    }

    public static boolean isDebian() {

        // we are just going to run "dpkg -s coreutils" and assume Debian

        // or deritive if no error is returned.

        try {

            Executor.of(TOOL_DPKG, "-s", "coreutils").executeExpectSuccess();

            return true;

        } catch (IOException e) {

            // just fall thru

        }

        return false;

    }

    private void adjustPermissionsRecursive(File dir) throws IOException {

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

            @Override

            public FileVisitResult visitFile(Path file,

                    BasicFileAttributes attrs)

                    throws IOException {

                if (file.endsWith(".so") || !Files.isExecutable(file)) {

                    setPermissions(file.toFile(), "rw-r--r--");

                } else if (Files.isExecutable(file)) {

                    setPermissions(file.toFile(), "rwxr-xr-x");

                }

                return FileVisitResult.CONTINUE;

            }

            @Override

            public FileVisitResult postVisitDirectory(Path dir, IOException e)

                    throws IOException {

                if (e == null) {

                    setPermissions(dir.toFile(), "rwxr-xr-x");

                    return FileVisitResult.CONTINUE;

                } else {

                    // directory iteration failed

                    throw e;

                }

            }

        });

    }

    private class DebianFile {

        DebianFile(Path dstFilePath, String comment) {

            this.dstFilePath = dstFilePath;

            this.comment = comment;

        }

        DebianFile setExecutable() {

            permissions = "rwxr-xr-x";

            return this;

        }

        void create(Map<String, String> data, Map<String, ? super Object> params)

                throws IOException {

            createResource("template." + dstFilePath.getFileName().toString(),

                    params)

                    .setCategory(I18N.getString(comment))

                    .setSubstitutionData(data)

                    .saveToFile(dstFilePath);

            if (permissions != null) {

                setPermissions(dstFilePath.toFile(), permissions);

            }

        }

        private final Path dstFilePath;

        private final String comment;

        private String permissions;

    }

    private void prepareProjectConfig(Map<String, String> data,

            Map<String, ? super Object> params) throws IOException {

        Path configDir = createMetaPackage(params).sourceRoot().resolve("DEBIAN");

        List<DebianFile> debianFiles = new ArrayList<>();

        debianFiles.add(new DebianFile(

                configDir.resolve("control"),

                "resource.deb-control-file"));

        debianFiles.add(new DebianFile(

                configDir.resolve("preinst"),

                "resource.deb-preinstall-script").setExecutable());

        debianFiles.add(new DebianFile(

                configDir.resolve("prerm"),

                "resource.deb-prerm-script").setExecutable());

        debianFiles.add(new DebianFile(

                configDir.resolve("postinst"),

                "resource.deb-postinstall-script").setExecutable());

        debianFiles.add(new DebianFile(

                configDir.resolve("postrm"),

                "resource.deb-postrm-script").setExecutable());

        if (!StandardBundlerParam.isRuntimeInstaller(params)) {

            debianFiles.add(new DebianFile(

                    getConfig_CopyrightFile(params).toPath(),

                    "resource.copyright-file"));

        }

        for (DebianFile debianFile : debianFiles) {

            debianFile.create(data, params);

        }

    }

    @Override

    protected Map<String, String> createReplacementData(

            Map<String, ? super Object> params) throws IOException {

        Map<String, String> data = new HashMap<>();

        data.put("APPLICATION_MAINTAINER", MAINTAINER.fetchFrom(params));

        data.put("APPLICATION_SECTION", SECTION.fetchFrom(params));

        data.put("APPLICATION_COPYRIGHT", COPYRIGHT.fetchFrom(params));

        data.put("APPLICATION_LICENSE_TEXT", LICENSE_TEXT.fetchFrom(params));

        data.put("APPLICATION_ARCH", DEB_ARCH);

        data.put("APPLICATION_INSTALLED_SIZE", Long.toString(

                createMetaPackage(params).sourceApplicationLayout().sizeInBytes() >> 10));

        return data;

    }

    private File getConfig_CopyrightFile(Map<String, ? super Object> params) {

        PlatformPackage thePackage = createMetaPackage(params);

        return thePackage.sourceRoot().resolve(Path.of(".",

                LINUX_INSTALL_DIR.fetchFrom(params), PACKAGE_NAME.fetchFrom(

                params), "share/doc/copyright")).toFile();

    }

    private File buildDeb(Map<String, ? super Object> params,

            File outdir) throws IOException {

        File outFile = new File(outdir,

                FULL_PACKAGE_NAME.fetchFrom(params)+".deb");

        Log.verbose(MessageFormat.format(I18N.getString(

                "message.outputting-to-location"), outFile.getAbsolutePath()));

        PlatformPackage thePackage = createMetaPackage(params);

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

        cmdline.addAll(List.of(TOOL_FAKEROOT, TOOL_DPKG_DEB));

        if (Log.isVerbose()) {

            cmdline.add("--verbose");

        }

        cmdline.addAll(List.of("-b", thePackage.sourceRoot().toString(),

                outFile.getAbsolutePath()));

        // run dpkg

        Executor.of(cmdline.toArray(String[]::new)).executeExpectSuccess();

        Log.verbose(MessageFormat.format(I18N.getString(

                "message.output-to-location"), outFile.getAbsolutePath()));

        return outFile;

    }

    @Override

    public String getName() {

        return I18N.getString("deb.bundler.name");

    }

    @Override

    public String getID() {

        return "deb";

    }

    @Override

    public boolean supported(boolean runtimeInstaller) {

        return Platform.isLinux() && (new ToolValidator(TOOL_DPKG_DEB).validate() == null);

    }

    @Override

    public boolean isDefault() {

        return isDebian();

    }

}