/*

 * Copyright (c) 2015, 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.plugins;

import java.io.File;

import java.io.IOException;

import java.io.UncheckedIOException;

import java.nio.file.FileSystem;

import java.nio.file.Files;

import java.nio.file.PathMatcher;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

import java.util.function.ToIntFunction;

import jdk.tools.jlink.plugin.PluginException;

import jdk.tools.jlink.plugin.ResourcePool;

import jdk.tools.jlink.plugin.ResourcePoolBuilder;

import jdk.tools.jlink.plugin.ResourcePoolEntry;

import jdk.tools.jlink.plugin.Plugin;

import jdk.tools.jlink.internal.Utils;

/**

 *

 * Order Resources plugin

 */

public final class OrderResourcesPlugin implements Plugin {

    public static final String NAME = "order-resources";

    private static final FileSystem JRT_FILE_SYSTEM = Utils.jrtFileSystem();

    private final List<ToIntFunction<String>> filters;

    private final Map<String, Integer> orderedPaths;

    public OrderResourcesPlugin() {

        this.filters = new ArrayList<>();

        this.orderedPaths = new HashMap<>();

    }

    @Override

    public String getName() {

        return NAME;

    }

    static class SortWrapper {

        private final ResourcePoolEntry resource;

        private final int ordinal;

        SortWrapper(ResourcePoolEntry resource, int ordinal) {

            this.resource = resource;

            this.ordinal = ordinal;

        }

        ResourcePoolEntry getResource() {

            return resource;

        }

        String getPath() {

            return resource.path();

        }

        int getOrdinal() {

            return ordinal;

        }

    }

    private String stripModule(String path) {

        if (path.startsWith("/")) {

            int index = path.indexOf('/', 1);

            if (index != -1) {

                return path.substring(index + 1);

            }

        }

        return path;

    }

    private int getOrdinal(ResourcePoolEntry resource) {

        String path = resource.path();

        Integer value = orderedPaths.get(stripModule(path));

        if (value != null) {

            return value;

        }

        for (ToIntFunction<String> function : filters) {

            int ordinal = function.applyAsInt(path);

            if (ordinal != Integer.MAX_VALUE) {

                return ordinal;

            }

        }

        return Integer.MAX_VALUE;

    }

    private static int compare(SortWrapper wrapper1, SortWrapper wrapper2) {

        int compare = wrapper1.getOrdinal() - wrapper2.getOrdinal();

        if (compare != 0) {

            return compare;

        }

        return wrapper1.getPath().compareTo(wrapper2.getPath());

    }

    @Override

    public ResourcePool transform(ResourcePool in, ResourcePoolBuilder out) {

        in.entries()

                .filter(resource -> resource.type()

                        .equals(ResourcePoolEntry.Type.CLASS_OR_RESOURCE))

                .map((resource) -> new SortWrapper(resource, getOrdinal(resource)))

                .sorted(OrderResourcesPlugin::compare)

                .forEach((wrapper) -> out.add(wrapper.getResource()));

        in.entries()

                .filter(other -> !other.type()

                        .equals(ResourcePoolEntry.Type.CLASS_OR_RESOURCE))

                .forEach((other) -> out.add(other));

        return out.build();

    }

    @Override

    public Category getType() {

        return Category.SORTER;

    }

    @Override

    public String getDescription() {

        return PluginsResourceBundle.getDescription(NAME);

    }

    @Override

    public boolean hasArguments() {

        return true;

    }

    @Override

    public String getArgumentsDescription() {

       return PluginsResourceBundle.getArgument(NAME);

    }

    @Override

    public void configure(Map<String, String> config) {

        List<String> patterns = Utils.parseList(config.get(NAME));

        int ordinal = 0;

        for (String pattern : patterns) {

            if (pattern.startsWith("@")) {

                File file = new File(pattern.substring(1));

                if (file.exists()) {

                    List<String> lines;

                    try {

                        lines = Files.readAllLines(file.toPath());

                    } catch (IOException ex) {

                        throw new UncheckedIOException(ex);

                    }

                    for (String line : lines) {

                        if (!line.startsWith("#")) {

                            orderedPaths.put(line + ".class", ordinal++);

                        }

                    }

                }

            } else {

                final int result = ordinal++;

                final PathMatcher matcher = Utils.getPathMatcher(JRT_FILE_SYSTEM, pattern);

                ToIntFunction<String> function = (path)-> matcher.matches(JRT_FILE_SYSTEM.getPath(path)) ? result : Integer.MAX_VALUE;

                filters.add(function);

             }

        }

    }

}