/*

 * Copyright (c) 2014, 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.

 */

package jdk.tools.jlink.internal;

import java.io.IOException;

import java.io.InputStream;

import java.io.UncheckedIOException;

import java.nio.file.Path;

import java.util.Objects;

import java.util.stream.Stream;

import jdk.internal.jmod.JmodFile;

import jdk.tools.jlink.internal.Archive.Entry.EntryType;

/**

 * An Archive backed by a jmod file.

 */

public class JmodArchive implements Archive {

    private static final String JMOD_EXT    = ".jmod";

    /**

     * An entry located in a jmod file.

     */

    public class JmodEntry extends Entry {

        private final JmodFile.Entry entry;

        JmodEntry(String path, String name, EntryType type,

                  JmodFile.Entry entry) {

            super(JmodArchive.this, path, name, type);

            this.entry = Objects.requireNonNull(entry);

        }

        /**

         * Returns the number of uncompressed bytes for this entry.

         */

        @Override

        public long size() {

            return entry.size();

        }

        @Override

        public InputStream stream() throws IOException {

            return jmodFile.getInputStream(entry.section(), entry.name());

        }

    }

    private final Path file;

    private final String moduleName;

    private JmodFile jmodFile;

    public JmodArchive(String mn, Path jmod) {

        Objects.requireNonNull(mn);

        Objects.requireNonNull(jmod.getFileName());

        String filename = jmod.toString();

        if (!filename.endsWith(JMOD_EXT)) {

            throw new UnsupportedOperationException("Unsupported format: " + filename);

        }

        this.moduleName = mn;

        this.file = jmod;

    }

    @Override

    public String moduleName() {

        return moduleName;

    }

    @Override

    public Path getPath() {

        return file;

    }

    @Override

    public Stream<Entry> entries() {

        ensureOpen();

        return jmodFile.stream()

                       .map(this::toEntry);

    }

    @Override

    public void open() throws IOException {

        if (jmodFile != null) {

            jmodFile.close();

        }

        this.jmodFile = new JmodFile(file);

    }

    @Override

    public void close() throws IOException {

        if (jmodFile != null) {

            jmodFile.close();

        }

    }

    private void ensureOpen() {

        if (jmodFile == null) {

            try {

                open();

            } catch(IOException ioe){

                throw new UncheckedIOException(ioe);

            }

        }

    }

    private EntryType toEntryType(JmodFile.Section section) {

        switch (section) {

            case CLASSES:

                return EntryType.CLASS_OR_RESOURCE;

            case CONFIG:

                return EntryType.CONFIG;

            case HEADER_FILES:

                return EntryType.HEADER_FILE;

            case LEGAL_NOTICES:

                return EntryType.LEGAL_NOTICE;

            case MAN_PAGES:

                return EntryType.MAN_PAGE;

            case NATIVE_LIBS:

                return EntryType.NATIVE_LIB;

            case NATIVE_CMDS:

                return EntryType.NATIVE_CMD;

            default:

                throw new InternalError("unexpected entry: " + section);

        }

    }

    private Entry toEntry(JmodFile.Entry entry) {

        EntryType type = toEntryType(entry.section());

        String prefix = entry.section().jmodDir();

        String name = entry.name();

        String path = prefix + "/" + name;

        String resourceName = name;

        // The resource name represents the path of ResourcePoolEntry

        // and its subpath defines the ultimate path to be written

        // to the image relative to the directory corresponding to that

        // resource type.

        //

        // For classes and resources, the resource name does not have

        // a prefix (<package>/<name>). They will be written to the jimage.

        //

        // For other kind of entries, it will keep the section name as

        // the prefix for unique identification.  The subpath (taking

        // out the section name) is the pathname to be written to the

        // corresponding directory in the image.

        //

        if (type == EntryType.LEGAL_NOTICE) {

            // legal notices are written to per-module directory

            resourceName = prefix + "/" + moduleName + "/" + name;

        } else if (type != EntryType.CLASS_OR_RESOURCE) {

            resourceName = path;

        }

        return new JmodEntry(path, resourceName, type, entry);

    }

}