/*

 * 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 com.sun.tools.jdeps;

import java.lang.module.ModuleDescriptor;

import java.net.URI;

import java.util.Collections;

import java.util.HashMap;

import java.util.HashSet;

import java.util.Map;

import java.util.Set;

/**

 * Jdeps internal representation of module for dependency analysis.

 */

class Module extends Archive {

    static final Module UNNAMED_MODULE = new UnnamedModule();

    static final String JDK_UNSUPPORTED = "jdk.unsupported";

    static final boolean DEBUG = Boolean.getBoolean("jdeps.debug");

    static void trace(String fmt, Object... args) {

        trace(DEBUG, fmt, args);

    }

    static void trace(boolean traceOn, String fmt, Object... args) {

        if (traceOn) {

            System.err.format(fmt, args);

        }

    }

    private final ModuleDescriptor descriptor;

    private final Map<String, Set<String>> exports;

    private final Map<String, Set<String>> opens;

    private final boolean isSystem;

    private final URI location;

    protected Module(String name) {

        super(name);

        this.descriptor = null;

        this.location = null;

        this.exports = Collections.emptyMap();

        this.opens = Collections.emptyMap();

        this.isSystem = true;

    }

    private Module(String name,

                   URI location,

                   ModuleDescriptor descriptor,

                   Map<String, Set<String>> exports,

                   Map<String, Set<String>> opens,

                   boolean isSystem,

                   ClassFileReader reader) {

        super(name, location, reader);

        this.descriptor = descriptor;

        this.location = location;

        this.exports = Collections.unmodifiableMap(exports);

        this.opens = Collections.unmodifiableMap(opens);

        this.isSystem = isSystem;

    }

    /**

     * Returns module name

     */

    public String name() {

        return descriptor != null ? descriptor.name() : getName();

    }

    public boolean isNamed() {

        return true;

    }

    public boolean isAutomatic() {

        return descriptor.isAutomatic();

    }

    public Module getModule() {

        return this;

    }

    public ModuleDescriptor descriptor() {

        return descriptor;

    }

    public URI location() {

        return location;

    }

    public boolean isJDK() {

        String mn = name();

        return isSystem &&

            (mn.startsWith("java.") || mn.startsWith("jdk.") || mn.startsWith("javafx."));

    }

    public boolean isSystem() {

        return isSystem;

    }

    public Map<String, Set<String>> exports() {

        return exports;

    }

    public Set<String> packages() {

        return descriptor.packages();

    }

    public boolean isJDKUnsupported() {

        return JDK_UNSUPPORTED.equals(this.name());

    }

    /**

     * Converts this module to a normal module with the given dependences

     *

     * @throws IllegalArgumentException if this module is not an automatic module

     */

    public Module toNormalModule(Map<String, Boolean> requires) {

        if (!isAutomatic()) {

            throw new IllegalArgumentException(name() + " not an automatic module");

        }

        return new NormalModule(this, requires);

    }

    /**

     * Tests if the package of the given name is exported.

     */

    public boolean isExported(String pn) {

        return exports.containsKey(pn) && exports.get(pn).isEmpty();

    }

    /**

     * Tests if the package of the given name is exported to the target

     * in a qualified fashion.

     */

    public boolean isExported(String pn, String target) {

        return isExported(pn)

                || exports.containsKey(pn) && exports.get(pn).contains(target);

    }

    /**

     * Tests if the package of the given name is open.

     */

    public boolean isOpen(String pn) {

        return opens.containsKey(pn) && opens.get(pn).isEmpty();

    }

    /**

     * Tests if the package of the given name is open to the target

     * in a qualified fashion.

     */

    public boolean isOpen(String pn, String target) {

        return isOpen(pn)

            || opens.containsKey(pn) && opens.get(pn).contains(target);

    }

    @Override

    public String toString() {

        return name();

    }

    public final static class Builder {

        final String name;

        final ModuleDescriptor descriptor;

        final boolean isSystem;

        ClassFileReader reader;

        URI location;

        public Builder(ModuleDescriptor md) {

            this(md, false);

        }

        public Builder(ModuleDescriptor md, boolean isSystem) {

            this.name = md.name();

            this.descriptor = md;

            this.isSystem = isSystem;

        }

        public Builder location(URI location) {

            this.location = location;

            return this;

        }

        public Builder classes(ClassFileReader reader) {

            this.reader = reader;

            return this;

        }

        public Module build() {

            if (descriptor.isAutomatic() && isSystem) {

                throw new InternalError("JDK module: " + name + " can't be automatic module");

            }

            Map<String, Set<String>> exports = new HashMap<>();

            Map<String, Set<String>> opens = new HashMap<>();

            if (descriptor.isAutomatic()) {

                // ModuleDescriptor::exports and opens returns an empty set

                descriptor.packages().forEach(pn -> exports.put(pn, Collections.emptySet()));

                descriptor.packages().forEach(pn -> opens.put(pn, Collections.emptySet()));

            } else {

                descriptor.exports().stream()

                          .forEach(exp -> exports.computeIfAbsent(exp.source(), _k -> new HashSet<>())

                                                 .addAll(exp.targets()));

                descriptor.opens().stream()

                    .forEach(exp -> opens.computeIfAbsent(exp.source(), _k -> new HashSet<>())

                        .addAll(exp.targets()));

            }

            return new Module(name, location, descriptor, exports, opens, isSystem, reader);

        }

    }

    private static class UnnamedModule extends Module {

        private UnnamedModule() {

            super("unnamed", null, null,

                  Collections.emptyMap(), Collections.emptyMap(),

                  false, null);

        }

        @Override

        public String name() {

            return "unnamed";

        }

        @Override

        public boolean isNamed() {

            return false;

        }

        @Override

        public boolean isAutomatic() {

            return false;

        }

        @Override

        public boolean isExported(String pn) {

            return true;

        }

    }

    /**

     * A normal module has a module-info.class

     */

    private static class NormalModule extends Module {

        private final ModuleDescriptor md;

        /**

         * Converts the given automatic module to a normal module.

         *

         * Replace this module's dependences with the given requires and also

         * declare service providers, if specified in META-INF/services configuration file

         */

        private NormalModule(Module m, Map<String, Boolean> requires) {

            super(m.name(), m.location, m.descriptor, m.exports, m.opens, m.isSystem, m.reader());

            ModuleDescriptor.Builder builder = ModuleDescriptor.newModule(m.name());

            requires.keySet().forEach(mn -> {

                if (requires.get(mn).equals(Boolean.TRUE)) {

                    builder.requires(Set.of(ModuleDescriptor.Requires.Modifier.TRANSITIVE), mn);

                } else {

                    builder.requires(mn);

                }

            });

            // exports all packages

            m.descriptor.packages().forEach(builder::exports);

            m.descriptor.uses().forEach(builder::uses);

            m.descriptor.provides().forEach(builder::provides);

            this.md = builder.build();

        }

        @Override

        public ModuleDescriptor descriptor() {

            return md;

        }

    }

}