/*

 * 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

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 */

package com.sun.tools.jdeps;

import java.util.Collections;

import java.util.HashMap;

import java.util.HashSet;

import java.util.Map;

import java.util.Objects;

import java.util.Set;

/**

 * JDeps internal representation of module for dependency analysis.

 */

final class Module extends Archive {

    private final String moduleName;

    private final Map<String, Boolean> requires;

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

    private final Set<String> packages;

    private Module(ClassFileReader reader, String name,

                   Map<String, Boolean> requires,

                   Map<String, Set<String>> exports,

                   Set<String> packages) {

        super(name, reader);

        this.moduleName = name;

        this.requires = Collections.unmodifiableMap(requires);

        this.exports = Collections.unmodifiableMap(exports);

        this.packages = Collections.unmodifiableSet(packages);

    }

    public String name() {

        return moduleName;

    }

    public Map<String, Boolean> requires() {

        return requires;

    }

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

        return exports;

    }

    public Set<String> packages() {

        return packages;

    }

    /**

     * Tests if this module can read m

     */

    public boolean canRead(Module m) {

        // ## TODO: handle "re-exported=true"

        // all JDK modules require all modules containing its direct dependences

        // should not be an issue

        return requires.containsKey(m.name());

    }

    /**

     * Tests if a given fully-qualified name is an exported type.

     */

    public boolean isExported(String cn) {

        int i = cn.lastIndexOf('.');

        String pn = i > 0 ? cn.substring(0, i) : "";

        return isExportedPackage(pn);

    }

    /**

     * Tests if a given package name is exported.

     */

    public boolean isExportedPackage(String pn) {

        return exports.containsKey(pn) ? exports.get(pn).isEmpty() : false;

    }

    /**

     * Tests if the given classname is accessible to module m

     */

    public boolean isAccessibleTo(String classname, Module m) {

        int i = classname.lastIndexOf('.');

        String pn = i > 0 ? classname.substring(0, i) : "";

        if (!packages.contains(pn)) {

            throw new IllegalArgumentException(classname + " is not a member of module " + name());

        }

        if (m != null && !m.canRead(this)) {

            trace("%s not readable by %s%n", this.name(), m.name());

            return false;

        }

        // exported API

        Set<String> ms = exports().get(pn);

        String mname = m != null ? m.name() : "unnamed";

        if (ms == null) {

            trace("%s not exported in %s%n", classname, this.name());

        } else if (!(ms.isEmpty() || ms.contains(mname))) {

            trace("%s not permit to %s %s%n", classname, mname, ms);

        }

        return ms != null && (ms.isEmpty() || ms.contains(mname));

    }

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

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

        if (traceOn) {

            System.err.format(fmt, args);

        }

    }

    @Override

    public boolean equals(Object ob) {

        if (!(ob instanceof Module))

            return false;

        Module that = (Module)ob;

        return (moduleName.equals(that.moduleName)

                && requires.equals(that.requires)

                && exports.equals(that.exports)

                && packages.equals(that.packages));

    }

    @Override

    public int hashCode() {

        int hc = moduleName.hashCode();

        hc = hc * 43 + requires.hashCode();

        hc = hc * 43 + exports.hashCode();

        hc = hc * 43 + packages.hashCode();

        return hc;

    }

    @Override

    public String toString() {

        return name();

    }

    public final static class Builder {

        String name;

        ClassFileReader reader;

        final Map<String, Boolean> requires = new HashMap<>();

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

        final Set<String> packages = new HashSet<>();

        public Builder() {

        }

        public Builder name(String n) {

            name = n;

            return this;

        }

        public Builder require(String d, boolean reexport) {

         //   System.err.format("%s depend %s reexports %s%n", name, d, reexport);

            requires.put(d, reexport);

            return this;

        }

        public Builder packages(Set<String> pkgs) {

            packages.addAll(pkgs);

            return this;

        }

        public Builder export(String p, Set<String> ms) {

            Objects.requireNonNull(p);

            Objects.requireNonNull(ms);

            exports.put(p, new HashSet<>(ms));

            return this;

        }

        public Builder classes(ClassFileReader.ModuleClassReader reader) {

            this.reader = reader;

            return this;

        }

        public Module build() {

            Module m = new Module(reader, name, requires, exports, packages);

            return m;

        }

    }

}