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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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package com.sun.tools.jdeps;

import java.io.IOException;
import java.io.PrintWriter;
import java.lang.module.ModuleDescriptor;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import java.util.TreeSet;
import java.util.stream.Collectors;
import java.util.stream.Stream;

Analyze module dependences and any reference to JDK internal APIs.
It can apply transition reduction on the resulting module graph.
The result prints one line per module it depends on
one line per JDK internal API package it references:
    $MODULE[/$PACKAGE]
/**
 * Analyze module dependences and any reference to JDK internal APIs.
 * It can apply transition reduction on the resulting module graph.
 *
 * The result prints one line per module it depends on
 * one line per JDK internal API package it references:
 *     $MODULE[/$PACKAGE]
 *
 */
public class ModuleExportsAnalyzer extends DepsAnalyzer {
    // source archive to its dependences and JDK internal APIs it references
    private final Map<Archive, Map<Archive,Set<String>>> deps = new HashMap<>();
    private final boolean showJdkInternals;
    private final boolean reduced;
    private final PrintWriter writer;
    private final String separator;
    public ModuleExportsAnalyzer(JdepsConfiguration config,
                                 JdepsFilter filter,
                                 boolean showJdkInternals,
                                 boolean reduced,
                                 PrintWriter writer,
                                 String separator) {
        super(config, filter, null,
              Analyzer.Type.PACKAGE,
              false /* all classes */);
        this.showJdkInternals = showJdkInternals;
        this.reduced = reduced;
        this.writer = writer;
        this.separator = separator;
    }

    @Override
    public boolean run() throws IOException {
        // analyze dependences
        boolean rc = super.run();

        // A visitor to record the module-level dependences as well as
        // use of JDK internal APIs
        Analyzer.Visitor visitor = (origin, originArchive, target, targetArchive) -> {
            Set<String> jdkInternals =
                deps.computeIfAbsent(originArchive, _k -> new HashMap<>())
                    .computeIfAbsent(targetArchive, _k -> new HashSet<>());

            Module module = targetArchive.getModule();
            if (showJdkInternals && originArchive.getModule() != module &&
                    module.isJDK() && !module.isExported(target)) {
                // use of JDK internal APIs
                jdkInternals.add(target);
            }
        };

        // visit the dependences
        archives.stream()
            .filter(analyzer::hasDependences)
            .sorted(Comparator.comparing(Archive::getName))
            .forEach(archive -> analyzer.visitDependences(archive, visitor));

        Set<Module> modules = modules();
        if (showJdkInternals) {
            // print modules and JDK internal API dependences
            printDependences(modules);
        } else {
            // print module dependences
            writer.println(modules.stream().map(Module::name).sorted()
                                  .collect(Collectors.joining(separator)));
        }
        return rc;
    }

    private Set<Module> modules() {
        // build module graph
        ModuleGraphBuilder builder = new ModuleGraphBuilder(configuration);
        Module root = new RootModule("root");
        builder.addModule(root);
        // find named module dependences
        dependenceStream()
            .flatMap(map -> map.keySet().stream())
            .filter(m -> m.getModule().isNamed()
                && !configuration.rootModules().contains(m))
            .map(Archive::getModule)
            .forEach(m -> builder.addEdge(root, m));

        // build module dependence graph
        // if reduced is set, apply transition reduction
        Graph<Module> g = reduced ? builder.reduced() : builder.build();
        return g.adjacentNodes(root);
    }

    private void printDependences(Set<Module> modules) {
        // find use of JDK internals
        Map<Module, Set<String>> jdkinternals = new HashMap<>();
        dependenceStream()
            .flatMap(map -> map.entrySet().stream())
            .filter(e -> e.getValue().size() > 0)
            .forEach(e -> jdkinternals.computeIfAbsent(e.getKey().getModule(),
                                                       _k -> new TreeSet<>())
                                      .addAll(e.getValue()));

        // print modules and JDK internal API dependences
        Stream.concat(modules.stream(), jdkinternals.keySet().stream())
              .sorted(Comparator.comparing(Module::name))
              .distinct()
              .forEach(m -> {
                  if (jdkinternals.containsKey(m)) {
                      jdkinternals.get(m).stream()
                          .forEach(pn -> writer.format("   %s/%s%s", m, pn, separator));
                  } else {
                      writer.format("   %s%s", m, separator);
                  }
              });
    }

    /*
     * Returns a stream of dependence map from an Archive to the set of JDK
     * internal APIs being used.
     */
    private Stream<Map<Archive, Set<String>>> dependenceStream() {
        return deps.keySet().stream()
                   .filter(source -> !source.getModule().isNamed()
                            || configuration.rootModules().contains(source))
                   .map(deps::get);
    }

    private class RootModule extends Module {
        final ModuleDescriptor descriptor;
        RootModule(String name) {
            super(name);

            ModuleDescriptor.Builder builder = ModuleDescriptor.newModule(name);
            this.descriptor = builder.build();
        }

        @Override
        public ModuleDescriptor descriptor() {
            return descriptor;
        }
    }

}