package org.apache.maven.plugins.jlink;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.NoSuchElementException;
import java.util.Optional;

import org.apache.commons.io.FileUtils;
import org.apache.maven.artifact.Artifact;
import org.apache.maven.plugin.MojoExecutionException;
import org.apache.maven.plugin.MojoFailureException;
import org.apache.maven.plugins.annotations.Component;
import org.apache.maven.plugins.annotations.LifecyclePhase;
import org.apache.maven.plugins.annotations.Mojo;
import org.apache.maven.plugins.annotations.Parameter;
import org.apache.maven.plugins.annotations.ResolutionScope;
import org.apache.maven.project.MavenProject;
import org.apache.maven.project.MavenProjectHelper;
import org.apache.maven.toolchain.Toolchain;
import org.apache.maven.toolchain.ToolchainPrivate;
import org.apache.maven.toolchain.java.DefaultJavaToolChain;
import org.codehaus.plexus.archiver.Archiver;
import org.codehaus.plexus.archiver.ArchiverException;
import org.codehaus.plexus.archiver.zip.ZipArchiver;
import org.codehaus.plexus.languages.java.jpms.JavaModuleDescriptor;
import org.codehaus.plexus.languages.java.jpms.LocationManager;
import org.codehaus.plexus.languages.java.jpms.ResolvePathsRequest;
import org.codehaus.plexus.languages.java.jpms.ResolvePathsResult;
import org.codehaus.plexus.languages.java.version.JavaVersion;

import static java.util.Collections.singletonMap;

/**
 * The JLink goal is intended to create a Java Run Time Image file based on
 * <a href="https://openjdk.java.net/jeps/282">https://openjdk.java.net/jeps/282</a>,
 * <a href="https://openjdk.java.net/jeps/220">https://openjdk.java.net/jeps/220</a>.
 * 
 * @author Karl Heinz Marbaise <a href="mailto:khmarbaise@apache.org">khmarbaise@apache.org</a>
 */
@Mojo( name = "jlink", requiresDependencyResolution = ResolutionScope.RUNTIME, defaultPhase = LifecyclePhase.PACKAGE )
public class JLinkMojo
    extends AbstractJLinkMojo
{
    @Component
    private LocationManager locationManager;

    /**
     * <p>
     * Specify the requirements for this jdk toolchain. This overrules the toolchain selected by the
     * maven-toolchain-plugin.
     * </p>
     * <strong>note:</strong> requires at least Maven 3.3.1
     */
    @Parameter
    private Map<String, String> jdkToolchain;

    /**
     * This is intended to strip debug information out. The command line equivalent of <code>jlink</code> is:
     * <code>-G, --strip-debug</code> strip debug information.
     */
    @Parameter( defaultValue = "false" )
    private boolean stripDebug;

    /**
     * Here you can define the compression of the resources being used. The command line equivalent is:
     * <code>-c, --compress=level&gt;</code>. The valid values for the level are: <code>0, 1, 2</code>.
     */
    @Parameter
    private Integer compress;

    /**
     * Should the plugin generate a launcher script by means of jlink? The command line equivalent is:
     * <code>--launcher &lt;name&gt;=&lt;module&gt;[/&lt;mainclass&gt;]</code>. The valid values for the level are:
     * <code>&lt;name&gt;=&lt;module&gt;[/&lt;mainclass&gt;]</code>.
     */
    @Parameter
    private String launcher;

    /**
     * These JVM arguments will be appended to the {@code lib/modules} file.<br>
     * <strong>This parameter requires at least JDK 14.<br></strong>
     *
     * <p>The command line equivalent is: {@code jlink --add-options="..."}.</p>
     *
     * <p>Example:</p>
     *
     * <pre>
     *   &lt;addOptions&gt;
     *     &lt;addOption&gt;-Xmx256m&lt;/addOption&gt;
     *     &lt;addOption&gt;--enable-preview&lt;/addOption&gt;
     *     &lt;addOption&gt;-Dvar=value&lt;/addOption&gt;
     *   &lt;/addOptions&gt;
     * </pre>
     *
     * <p>Above example will result in {@code jlink --add-options="-Xmx256m" --enable-preview -Dvar=value"}.</p>
     */
    @Parameter
    private List<String> addOptions;

    /**
     * Limit the universe of observable modules. The following gives an example of the configuration which can be used
     * in the <code>pom.xml</code> file.
     * 
     * <pre>
     *   &lt;limitModules&gt;
     *     &lt;limitModule&gt;mod1&lt;/limitModule&gt;
     *     &lt;limitModule&gt;xyz&lt;/limitModule&gt;
     *     .
     *     .
     *   &lt;/limitModules&gt;
     * </pre>
     * 
     * This configuration is the equivalent of the command line option:
     * <code>--limit-modules &lt;mod&gt;[,&lt;mod&gt;...]</code>
     */
    @Parameter
    private List<String> limitModules;

    /**
     * <p>
     * Usually this is not necessary, cause this is handled automatically by the given dependencies.
     * </p>
     * <p>
     * By using the --add-modules you can define the root modules to be resolved. The configuration in
     * <code>pom.xml</code> file can look like this:
     * </p>
     * 
     * <pre>
     * &lt;addModules&gt;
     *   &lt;addModule&gt;mod1&lt;/addModule&gt;
     *   &lt;addModule&gt;first&lt;/addModule&gt;
     *   .
     *   .
     * &lt;/addModules&gt;
     * </pre>
     * 
     * The command line equivalent for jlink is: <code>--add-modules &lt;mod&gt;[,&lt;mod&gt;...]</code>.
     */
    @Parameter
    private List<String> addModules;

    /**
     * Define the plugin module path to be used. There can be defined multiple entries separated by either {@code ;} or
     * {@code :}. The jlink command line equivalent is: <code>--plugin-module-path &lt;modulepath&gt;</code>
     */
    @Parameter
    private String pluginModulePath;

    /**
     * The output directory for the resulting Run Time Image. The created Run Time Image is stored in non compressed
     * form. This will later being packaged into a <code>zip</code> file. <code>--output &lt;path&gt;</code>
     *
     * <p>The {@link #classifier} is appended as a subdirecty if it exists,
     * otherwise {@code default} will be used as subdirectory.
     * This ensures that multiple executions using classifiers will not overwrite the previous run’s image.</p>
     */
    @Parameter( defaultValue = "${project.build.directory}/maven-jlink", required = true, readonly = true )
    private File outputDirectoryImage;

    @Parameter( defaultValue = "${project.build.directory}", required = true, readonly = true )
    private File buildDirectory;

    @Parameter( defaultValue = "${project.build.outputDirectory}", required = true, readonly = true )
    private File outputDirectory;

    /**
     * The byte order of the generated Java Run Time image. <code>--endian &lt;little|big&gt;</code>. If the endian is
     * not given the default is: <code>native</code>.
     */
    // TODO: Should we define either little or big as default? or should we left as it.
    @Parameter
    private String endian;

    /**
     * Include additional paths on the <code>--module-path</code> option. Project dependencies and JDK modules are
     * automatically added.
     */
    @Parameter
    private List<String> modulePaths;

    /**
     * Add the option <code>--bind-services</code> or not.
     */
    @Parameter( defaultValue = "false" )
    private boolean bindServices;

    /**
     * You can disable a plugin by using this option. <code>--disable-plugin pluginName</code>.
     */
    @Parameter
    private String disablePlugin;

    /**
     * <code>--ignore-signing-information</code>
     */
    @Parameter( defaultValue = "false" )
    private boolean ignoreSigningInformation;

    /**
     * This will suppress to have an <code>includes</code> directory in the resulting Java Run Time Image. The JLink
     * command line equivalent is: <code>--no-header-files</code>
     */
    @Parameter( defaultValue = "false" )
    private boolean noHeaderFiles;

    /**
     * This will suppress to have the <code>man</code> directory in the resulting Java Run Time Image. The JLink command
     * line equivalent is: <code>--no-man-pages</code>
     */
    @Parameter( defaultValue = "false" )
    private boolean noManPages;

    /**
     * Suggest providers that implement the given service types from the module path.
     * 
     * <pre>
     * &lt;suggestProviders&gt;
     *   &lt;suggestProvider&gt;name-a&lt;/suggestProvider&gt;
     *   &lt;suggestProvider&gt;name-b&lt;/suggestProvider&gt;
     *   .
     *   .
     * &lt;/suggestProviders&gt;
     * </pre>
     * 
     * The jlink command linke equivalent: <code>--suggest-providers [&lt;name&gt;,...]</code>
     */
    @Parameter
    private List<String> suggestProviders;

    /**
     * Includes the list of locales where langtag is a BCP 47 language tag.
     *
     * <p>This option supports locale matching as defined in RFC 4647.
     * Ensure that you add the module jdk.localedata when using this option.</p>
     *
     * <p>The command line equivalent is: <code>--include-locales=en,ja,*-IN</code>.</p>
     *
     * <pre>
     * &lt;includeLocales&gt;
     *   &lt;includeLocale&gt;en&lt;/includeLocale&gt;
     *   &lt;includeLocale&gt;ja&lt;/includeLocale&gt;
     *   &lt;includeLocale&gt;*-IN&lt;/includeLocale&gt;
     *   .
     *   .
     * &lt;/includeLocales&gt;
     * </pre>
     */
    @Parameter
    private List<String> includeLocales;

    /**
     * This will turn on verbose mode. The jlink command line equivalent is: <code>--verbose</code>
     */
    @Parameter( defaultValue = "false" )
    private boolean verbose;

    /**
     * The JAR archiver needed for archiving the environments.
     */
    @Component( role = Archiver.class, hint = "zip" )
    private ZipArchiver zipArchiver;

    /**
     * Set the JDK location to create a Java custom runtime image.
     */
    @Parameter
    private File sourceJdkModules;

    /**
     * Classifier to add to the artifact generated. If given, the artifact will be attached
     * as a supplemental artifact.
     * If not given this will create the main artifact which is the default behavior.
     * If you try to do that a second time without using a classifier the build will fail.
     */
    @Parameter
    private String classifier;

    /**
     * Name of the generated ZIP file in the <code>target</code> directory. This will not change the name of the
     * installed/deployed file.
     */
    @Parameter( defaultValue = "${project.build.finalName}", readonly = true )
    private String finalName;

    /**
     * Convenience interface for plugins to add or replace artifacts and resources on projects.
     */
    @Component
    private MavenProjectHelper projectHelper;

    @Override
    public void execute() throws MojoExecutionException, MojoFailureException
    {
        failIfParametersAreNotInTheirValidValueRanges();

        setOutputDirectoryImage();

        ifOutputDirectoryExistsDelteIt();

        JLinkExecutor jLinkExec = getExecutor();
        Collection<String> modulesToAdd = new ArrayList<>();
        if ( addModules != null )
        {
            modulesToAdd.addAll( addModules );
        }
        jLinkExec.addAllModules( modulesToAdd );

        Collection<String> pathsOfModules = new ArrayList<>();
        if ( modulePaths != null )
        {
            pathsOfModules.addAll( modulePaths );
        }

        for ( Entry<String, File> item : getModulePathElements().entrySet() )
        {
            getLog().info( " -> module: " + item.getKey() + " ( " + item.getValue().getPath() + " )" );

            // We use the real module name and not the artifact Id...
            modulesToAdd.add( item.getKey() );
            pathsOfModules.add( item.getValue().getPath() );
        }

        // The jmods directory of the JDK
        jLinkExec.getJmodsFolder( this.sourceJdkModules ).ifPresent(
                jmodsFolder -> pathsOfModules.add( jmodsFolder.getAbsolutePath() )
        );
        jLinkExec.addAllModulePaths( pathsOfModules );

        List<String> jlinkArgs = createJlinkArgs( pathsOfModules, modulesToAdd );

        try
        {
            jLinkExec.executeJlink( jlinkArgs );
        }
        catch ( IllegalStateException e )
        {
            throw new MojoFailureException( "Unable to find jlink command: " + e.getMessage(), e );
        }

        File createZipArchiveFromImage = createZipArchiveFromImage( buildDirectory, outputDirectoryImage );

        if ( hasClassifier() )
        {
            projectHelper.attachArtifact( getProject(), "jlink", getClassifier(), createZipArchiveFromImage );
        }
        else
        {
            if ( projectHasAlreadySetAnArtifact() )
            {
                throw new MojoExecutionException( "You have to use a classifier "
                        + "to attach supplemental artifacts to the project instead of replacing them." );
            }
            getProject().getArtifact().setFile( createZipArchiveFromImage );
        }
    }

    private List<File> getCompileClasspathElements( MavenProject project )
    {
        List<File> list = new ArrayList<>( project.getArtifacts().size() + 1 );

        for ( Artifact a : project.getArtifacts() )
        {
            getLog().debug( "Artifact: " + a.getGroupId() + ":" + a.getArtifactId() + ":" + a.getVersion() );
            list.add( a.getFile() );
        }
        return list;
    }

    private Map<String, File> getModulePathElements()
        throws MojoFailureException
    {
        // For now only allow named modules. Once we can create a graph with ASM we can specify exactly the modules
        // and we can detect if auto modules are used. In that case, MavenProject.setFile() should not be used, so
        // you cannot depend on this project and so it won't be distributed.

        Map<String, File> modulepathElements = new HashMap<>();

        try
        {
            Collection<File> dependencyArtifacts = getCompileClasspathElements( getProject() );

            ResolvePathsRequest<File> request = ResolvePathsRequest.ofFiles( dependencyArtifacts );

            Optional<Toolchain> toolchain = getToolchain();
            if ( toolchain.isPresent()
                    && toolchain.orElseThrow( NoSuchElementException::new ) instanceof DefaultJavaToolChain )
            {
                Toolchain toolcahin1 = toolchain.orElseThrow( NoSuchElementException::new );
                request.setJdkHome( new File( ( (DefaultJavaToolChain) toolcahin1 ).getJavaHome() ) );
            }

            ResolvePathsResult<File> resolvePathsResult = locationManager.resolvePaths( request );

            for ( Map.Entry<File, JavaModuleDescriptor> entry : resolvePathsResult.getPathElements().entrySet() )
            {
                JavaModuleDescriptor descriptor = entry.getValue();
                if ( descriptor == null )
                {
                    String message = "The given dependency " + entry.getKey()
                        + " does not have a module-info.java file. So it can't be linked.";
                    getLog().error( message );
                    throw new MojoFailureException( message );
                }

                // Don't warn for automatic modules, let the jlink tool do that
                getLog().debug( " module: " + descriptor.name() + " automatic: " + descriptor.isAutomatic() );
                if ( modulepathElements.containsKey( descriptor.name() ) )
                {
                    getLog().warn( "The module name " + descriptor.name() + " does already exists." );
                }
                modulepathElements.put( descriptor.name(), entry.getKey() );
            }

            // This part is for the module in target/classes ? (Hacky..)
            // FIXME: Is there a better way to identify that code exists?
            if ( outputDirectory.exists() )
            {
                List<File> singletonList = Collections.singletonList( outputDirectory );

                ResolvePathsRequest<File> singleModuls = ResolvePathsRequest.ofFiles( singletonList );

                ResolvePathsResult<File> resolvePaths = locationManager.resolvePaths( singleModuls );
                for ( Entry<File, JavaModuleDescriptor> entry : resolvePaths.getPathElements().entrySet() )
                {
                    JavaModuleDescriptor descriptor = entry.getValue();
                    if ( descriptor == null )
                    {
                        String message = "The given project " + entry.getKey()
                            + " does not contain a module-info.java file. So it can't be linked.";
                        getLog().error( message );
                        throw new MojoFailureException( message );
                    }
                    if ( modulepathElements.containsKey( descriptor.name() ) )
                    {
                        getLog().warn( "The module name " + descriptor.name() + " does already exists." );
                    }
                    modulepathElements.put( descriptor.name(), entry.getKey() );
                }
            }

        }
        catch ( IOException e )
        {
            getLog().error( e.getMessage() );
            throw new MojoFailureException( e.getMessage() );
        }

        return modulepathElements;
    }

    private JLinkExecutor getExecutor()
    {
        return getJlinkExecutor();
    }

    private boolean projectHasAlreadySetAnArtifact( )
    {
        if ( getProject().getArtifact().getFile() != null )
        {
            return getProject().getArtifact().getFile().isFile();
        }
        else
        {
            return false;
        }
    }

    /**
     * @return true in case where the classifier is not {@code null} and contains something else than white spaces.
     */
    protected boolean hasClassifier()
    {
        boolean result = false;
        if ( getClassifier() != null && !getClassifier().isEmpty() )
        {
            result = true;
        }

        return result;
    }

    private File createZipArchiveFromImage( File outputDirectory, File outputDirectoryImage )
        throws MojoExecutionException
    {
        zipArchiver.addDirectory( outputDirectoryImage );

        File resultArchive = getArchiveFile( outputDirectory, finalName, getClassifier(), "zip" );

        zipArchiver.setDestFile( resultArchive );
        try
        {
            zipArchiver.createArchive();
        }
        catch ( ArchiverException | IOException e )
        {
            getLog().error( e.getMessage(), e );
            throw new MojoExecutionException( e.getMessage(), e );
        }

        return resultArchive;

    }

    private void failIfParametersAreNotInTheirValidValueRanges()
        throws MojoFailureException
    {
        if ( compress != null && ( compress < 0 || compress > 2 ) )
        {
            String message = "The given compress parameters " + compress + " is not in the valid value range from 0..2";
            getLog().error( message );
            throw new MojoFailureException( message );
        }

        if ( endian != null && ( !"big".equals( endian ) && !"little".equals( endian ) ) )
        {
            String message = "The given endian parameter " + endian
                    + " does not contain one of the following values: 'little' or 'big'.";
            getLog().error( message );
            throw new MojoFailureException( message );
        }

        if ( addOptions != null && !addOptions.isEmpty() )
        {
            requireJdk14();
        }
    }

    private void requireJdk14() throws MojoFailureException
    {
        // needs JDK 14+
        Optional<Toolchain> optToolchain = getToolchain();
        String java14reqMsg = "parameter 'addOptions' needs at least a Java 14 runtime or a Java 14 toolchain.";

        if ( optToolchain.isPresent() )
        {
            Toolchain toolchain = optToolchain.orElseThrow( NoSuchElementException::new );
            if ( !( toolchain instanceof ToolchainPrivate ) )
            {
                getLog().warn( "Unable to check toolchain java version." );
                return;
            }
            ToolchainPrivate toolchainPrivate = (ToolchainPrivate) toolchain;
            if ( !toolchainPrivate.matchesRequirements( singletonMap( "jdk", "14" ) ) )
            {
                throw new MojoFailureException( java14reqMsg );
            }
        }
        else if ( !JavaVersion.JAVA_VERSION.isAtLeast( "14" ) )
        {
            throw new MojoFailureException( java14reqMsg );
        }
    }

    /**
     * Use a separate directory for each image.
     *
     * <p>Rationale: If a user creates multiple jlink artifacts using classifiers,
     * the directories should not overwrite themselves for each execution.</p>
     */
    private void setOutputDirectoryImage()
    {
        if ( hasClassifier() )
        {
            final File classifiersDirectory = new File( outputDirectoryImage, "classifiers" );
            outputDirectoryImage = new File( classifiersDirectory, classifier );
        }
        else
        {
            outputDirectoryImage = new File( outputDirectoryImage, "default" );
        }
    }

    private void ifOutputDirectoryExistsDelteIt()
        throws MojoExecutionException
    {
        if ( outputDirectoryImage.exists() )
        {
            // Delete the output folder of JLink before we start
            // otherwise JLink will fail with a message "Error: directory already exists: ..."
            try
            {
                getLog().debug( "Deleting existing " + outputDirectoryImage.getAbsolutePath() );
                FileUtils.forceDelete( outputDirectoryImage );
            }
            catch ( IOException e )
            {
                getLog().error( "IOException", e );
                throw new MojoExecutionException( "Failure during deletion of " + outputDirectoryImage.getAbsolutePath()
                    + " occured." );
            }
        }
    }

    private List<String> createJlinkArgs( Collection<String> pathsOfModules,
                                      Collection<String> modulesToAdd )
    {
        List<String> jlinkArgs = new ArrayList<>();

        if ( stripDebug )
        {
            jlinkArgs.add( "--strip-debug" );
        }

        if ( bindServices )
        {
            jlinkArgs.add( "--bind-services" );
        }

        if ( endian != null )
        {
            jlinkArgs.add( "--endian" );
            jlinkArgs.add( endian );
        }
        if ( ignoreSigningInformation )
        {
            jlinkArgs.add( "--ignore-signing-information" );
        }
        if ( compress != null )
        {
            jlinkArgs.add( "--compress" );
            jlinkArgs.add( compress + "" );
        }
        if ( launcher != null )
        {
            jlinkArgs.add( "--launcher" );
            jlinkArgs.add( launcher );
        }
        if ( addOptions != null && !addOptions.isEmpty() )
        {
            jlinkArgs.add( "--add-options" );
            jlinkArgs.add( String.format( "\"%s\"", String.join( " ", addOptions ) ) );
        }

        if ( disablePlugin != null )
        {
            jlinkArgs.add( "--disable-plugin" );
            jlinkArgs.add( disablePlugin );

        }
        if ( pathsOfModules != null )
        {
            // @formatter:off
            jlinkArgs.add( "--module-path" );
            jlinkArgs.add( getPlatformDependSeparateList( pathsOfModules ).replace( "\\", "\\\\" ) );
            // @formatter:off
        }

        if ( noHeaderFiles )
        {
            jlinkArgs.add( "--no-header-files" );
        }

        if ( noManPages )
        {
            jlinkArgs.add( "--no-man-pages" );
        }

        if ( hasSuggestProviders() )
        {
            jlinkArgs.add( "--suggest-providers" );
            String sb = getCommaSeparatedList( suggestProviders );
            jlinkArgs.add( sb );
        }

        if ( hasLimitModules() )
        {
            jlinkArgs.add( "--limit-modules" );
            String sb = getCommaSeparatedList( limitModules );
            jlinkArgs.add( sb );
        }

        if ( !modulesToAdd.isEmpty() )
        {
            jlinkArgs.add( "--add-modules" );
            // This must be name of the module and *NOT* the name of the
            // file! Can we somehow pre check this information to fail early?
            String sb = getCommaSeparatedList( modulesToAdd );
            jlinkArgs.add( sb.replace( "\\", "\\\\" ) );
        }

        if ( hasIncludeLocales() )
        {
            jlinkArgs.add( "--add-modules" );
            jlinkArgs.add( "jdk.localedata" );
            jlinkArgs.add( "--include-locales" );
            String sb = getCommaSeparatedList( includeLocales );
            jlinkArgs.add( sb );
        }

        if ( pluginModulePath != null )
        {
            jlinkArgs.add( "--plugin-module-path" );
            StringBuilder sb = convertSeparatedModulePathToPlatformSeparatedModulePath( pluginModulePath );
            jlinkArgs.add( sb.toString().replace( "\\", "\\\\" ) );
        }

        if ( buildDirectory != null )
        {
            jlinkArgs.add( "--output" );
            jlinkArgs.add( outputDirectoryImage.getAbsolutePath() );
        }

        if ( verbose )
        {
            jlinkArgs.add( "--verbose" );
        }

        return Collections.unmodifiableList( jlinkArgs );
    }

    private boolean hasIncludeLocales()
    {
        return includeLocales != null && !includeLocales.isEmpty();
    }

    private boolean hasSuggestProviders()
    {
        return suggestProviders != null && !suggestProviders.isEmpty();
    }

    private boolean hasLimitModules()
    {
        return limitModules != null && !limitModules.isEmpty();
    }

    /**
     * {@inheritDoc}
     */
    protected String getClassifier()
    {
        return classifier;
    }

}