/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification
 *             of Java bytecode.
 *
 * Copyright (c) 2002-2015 Eric Lafortune @ GuardSquare
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 * This program 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 for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard;

import proguard.classfile.ClassPool;
import proguard.classfile.visitor.*;
import proguard.optimize.*;

import java.io.*;

/**
 * This class prints out the seeds specified by keep options.
 *
 * @author Eric Lafortune
 */
public class SeedPrinter
{
    private final PrintStream ps;


    /**
     * Creates a new ConfigurationWriter for the given PrintStream.
     */
    public SeedPrinter(PrintStream ps) throws IOException
    {
        this.ps = ps;
    }


    /**
     * Prints out the seeds for the classes in the given program class pool.
     * @param configuration the configuration containing the keep options.
     * @throws IOException if an IO error occurs while writing the configuration.
     */
    public void write(Configuration configuration,
                      ClassPool     programClassPool,
                      ClassPool     libraryClassPool) throws IOException
    {
        // Check if we have at least some keep commands.
        if (configuration.keep == null)
        {
            throw new IOException("You have to specify '-keep' options for the shrinking step.");
        }

        // Clean up any old visitor info.
        programClassPool.classesAccept(new ClassCleaner());
        libraryClassPool.classesAccept(new ClassCleaner());

        // Create a visitor for printing out the seeds. We're  printing out
        // the program elements that are preserved against shrinking,
        // optimization, or obfuscation.
        KeepMarker keepMarker = new KeepMarker();
        ClassPoolVisitor classPoolvisitor =
            ClassSpecificationVisitorFactory.createClassPoolVisitor(configuration.keep,
                                                                    keepMarker,
                                                                    keepMarker,
                                                                    true,
                                                                    true,
                                                                    true);
        // Mark the seeds.
        programClassPool.accept(classPoolvisitor);
        libraryClassPool.accept(classPoolvisitor);

        // Print out the seeds.
        SimpleClassPrinter printer = new SimpleClassPrinter(false, ps);
        programClassPool.classesAcceptAlphabetically(new MultiClassVisitor(
            new ClassVisitor[]
            {
                new KeptClassFilter(printer),
                new AllMemberVisitor(new KeptMemberFilter(printer))
            }));
    }
}