/*
 * Copyright (c) 2016, 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
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 */
package jdk.tools.jlink.internal.plugins;

import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

import jdk.tools.jlink.plugin.Plugin;
import jdk.tools.jlink.plugin.PluginException;
import jdk.tools.jlink.plugin.ResourcePool;
import jdk.tools.jlink.plugin.ResourcePoolBuilder;
import jdk.tools.jlink.plugin.ResourcePoolEntry.Type;

/**
 *
 * A plugin to exclude a JMOD section such as man pages or header files
 */
public final class ExcludeJmodSectionPlugin implements Plugin {

    public static final String NAME = "exclude-jmod-section";
    public static final String MODULES = "modules";
    public static final String MAN_PAGES = "man";
    public static final String INCLUDE_HEADER_FILES = "headers";

    private final Map<Type, Set<String>> filters = new HashMap<>();

    @Override
    public String getName() {
        return NAME;
    }

    @Override
    public void configure(Map<String, String> config) {
        String arg = config.get(NAME);
        if (arg.isEmpty()) {
            throw new PluginException("Section name must be specified");
        }

        Type type;
        switch (arg) {
            case MAN_PAGES:
                type = Type.MAN_PAGE;
                break;
            case INCLUDE_HEADER_FILES:
                type = Type.HEADER_FILE;
                break;
            default:
                throw new PluginException("Invalid section name: " + arg);
        }

        if (filters.containsKey(type)) {
            throw new PluginException(type + " section already specified to be excluded");
        }

        Set<String> modules = new HashSet<>();
        filters.put(type, modules);

        // If modules is not set, empty set indicates all modules.
        String mods = config.get(MODULES);
        if (mods != null) {
            Arrays.stream(mods.split(","))
                  .filter(s -> s.length() > 0)
                  .forEach(modules::add);
            if (modules.isEmpty()) {
                throw new PluginException("Must specify modules to be excluded");
            }
        }
    }

    @Override
    public ResourcePool transform(ResourcePool in, ResourcePoolBuilder out) {
        in.transformAndCopy(entry -> {
            // filter entries whose type corresponds to the specified JMOD section
            // and matches the modules specified to be excluded.
            Set<String> modules = filters.get(entry.type());
            if (modules != null) {
                if (modules.isEmpty() || modules.contains(entry.moduleName())) {
                    entry = null;
                }
            }
            return entry;
        }, out);
        return out.build();
    }

    @Override
    public Category getType() {
        return Category.FILTER;
    }

    @Override
    public String getDescription() {
        return PluginsResourceBundle.getDescription(NAME);
    }

    @Override
    public boolean hasArguments() {
        return true;
    }

    @Override
    public String getArgumentsDescription() {
       return PluginsResourceBundle.getArgument(NAME);
    }
}