/*
 *
 * Copyright (c) 2013 - 2017 Lijun Liao
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License version 3
 * as published by the Free Software Foundation with the addition of the
 * following permission added to Section 15 as permitted in Section 7(a):
 *
 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
 * THE AUTHOR LIJUN LIAO. LIJUN LIAO DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
 * OF THIRD PARTY RIGHTS.
 *
 * 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU Affero General Public License.
 *
 * You can be released from the requirements of the license by purchasing
 * a commercial license. Buying such a license is mandatory as soon as you
 * develop commercial activities involving the XiPKI software without
 * disclosing the source code of your own applications.
 *
 * For more information, please contact Lijun Liao at this
 * address: lijun.liao@gmail.com
 */

package org.xipki.commons.password;

import java.util.Collections;
import java.util.Set;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.LinkedBlockingQueue;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * @author Lijun Liao
 * @since 2.0.0
 */

public class PasswordProducer {

    private static final Logger LOG = LoggerFactory.getLogger(PasswordProducer.class);

    private static ConcurrentHashMap<String, BlockingQueue<char[]>> namePasswordsMap =
            new ConcurrentHashMap<>();

    private static ConcurrentHashMap<String, Boolean> nameResultMap =
            new ConcurrentHashMap<>();

    public static void registerPasswordConsumer(final String name) {
        assertNameNotBlank(name);
        BlockingQueue<char[]> queue = new LinkedBlockingQueue<>(1);
        nameResultMap.remove(name);
        namePasswordsMap.put(name, queue);
        final String str = "registered password consumer " + name;
        System.out.println(str);
        LOG.info(str);
    }

    public static void unregisterPasswordConsumer(final String name) {
        assertNameNotBlank(name);
        namePasswordsMap.remove(name);
        final String str = "unregistered password consumer " + name;
        System.out.println(str);
        LOG.info(str);
    }

    public static void setPasswordCorrect(final String name, final boolean correct) {
        assertNameNotBlank(name);
        nameResultMap.put(name, correct);
        final String str = "set result of password consumer " + name + ": "
                + (correct ? "valid" : "invalid");
        System.out.println(str);
        LOG.info(str);
    }

    public static Boolean removePasswordCorrect(final String name) {
        return nameResultMap.remove(name);
    }

    public static char[] takePassword(final String name)
            throws InterruptedException, PasswordResolverException {
        assertNameNotBlank(name);
        if (!namePasswordsMap.containsKey(name)) {
            throw new PasswordResolverException("password consumer '" + name
                    + "' is not registered ");
        }
        char[] pwd = namePasswordsMap.get(name).take();
        final String str = "took password consumer " + name;
        System.out.println(str);
        return pwd;
    }

    public static void putPassword(final String name, final char[] password)
            throws InterruptedException, PasswordResolverException {
        assertNameNotBlank(name);
        if (!namePasswordsMap.containsKey(name)) {
            throw new PasswordResolverException("password consumer '" + name
                    + "' is not registered ");
        }

        nameResultMap.remove(name);
        namePasswordsMap.get(name).put(password);
        final String str = "provided password consumer " + name;
        System.out.println(str);
    }

    public static boolean needsPassword(final String name) {
        assertNameNotBlank(name);
        if (!namePasswordsMap.containsKey(name)) {
            return false;
        }
        return namePasswordsMap.get(name).isEmpty();
    }

    public static Set<String> getNames() {
        return Collections.unmodifiableSet(namePasswordsMap.keySet());
    }

    private static void assertNameNotBlank(final String name) {
        if (name == null) {
            throw new NullPointerException("name must not be null");
        }

        if (name.isEmpty()) {
            throw new IllegalArgumentException("name must not be empty");
        }
    }
}