/*
 * ====================================================================
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */
package org.apache.http.impl.client;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.TreeSet;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;

import org.apache.http.annotation.Contract;
import org.apache.http.annotation.ThreadingBehavior;
import org.apache.http.client.CookieStore;
import org.apache.http.cookie.Cookie;
import org.apache.http.cookie.CookieIdentityComparator;

Default implementation of CookieStore 
Since:
4.0/**
 * Default implementation of {@link CookieStore}
 *
 *
 * @since 4.0
 */
@Contract(threading = ThreadingBehavior.SAFE)
public class BasicCookieStore implements CookieStore, Serializable {

    private static final long serialVersionUID = -7581093305228232025L;

    private final TreeSet<Cookie> cookies;
    private transient ReadWriteLock lock;

    public BasicCookieStore() {
        super();
        this.cookies = new TreeSet<Cookie>(new CookieIdentityComparator());
        this.lock = new ReentrantReadWriteLock();
    }

    private void readObject(final ObjectInputStream stream) throws IOException, ClassNotFoundException {
        stream.defaultReadObject();

        /* Reinstantiate transient fields. */
        this.lock = new ReentrantReadWriteLock();
    }

    
Adds an HTTP cookie, replacing any existing equivalent cookies. If the given cookie has already expired it will not be added, but existing values will still be removed. 
Params:
cookie – the cookie to be added
See Also:
addCookies(Cookie[])/**
     * Adds an {@link Cookie HTTP cookie}, replacing any existing equivalent cookies.
     * If the given cookie has already expired it will not be added, but existing
     * values will still be removed.
     *
     * @param cookie the {@link Cookie cookie} to be added
     *
     * @see #addCookies(Cookie[])
     *
     */
    @Override
    public void addCookie(final Cookie cookie) {
        if (cookie != null) {
            lock.writeLock().lock();
            try {
                // first remove any old cookie that is equivalent
                cookies.remove(cookie);
                if (!cookie.isExpired(new Date())) {
                    cookies.add(cookie);
                }
            } finally {
                lock.writeLock().unlock();
            }
        }
    }

    
Adds an array of HTTP cookies. Cookies are added individually and in the given array order. If any of the given cookies has already expired it will not be added, but existing values will still be removed. 
Params:
cookies – the cookies to be added
See Also:
addCookie(Cookie)/**
     * Adds an array of {@link Cookie HTTP cookies}. Cookies are added individually and
     * in the given array order. If any of the given cookies has already expired it will
     * not be added, but existing values will still be removed.
     *
     * @param cookies the {@link Cookie cookies} to be added
     *
     * @see #addCookie(Cookie)
     *
     */
    public void addCookies(final Cookie[] cookies) {
        if (cookies != null) {
            for (final Cookie cookie : cookies) {
                this.addCookie(cookie);
            }
        }
    }

    
Returns an immutable array of cookies that this HTTP state currently contains. 
Returns:
an array of cookies./**
     * Returns an immutable array of {@link Cookie cookies} that this HTTP
     * state currently contains.
     *
     * @return an array of {@link Cookie cookies}.
     */
    @Override
    public List<Cookie> getCookies() {
        lock.readLock().lock();
        try {
            //create defensive copy so it won't be concurrently modified
            return new ArrayList<Cookie>(cookies);
        } finally {
            lock.readLock().unlock();
        }
    }

    
Removes all of cookies in this HTTP state that have expired by the specified date. 
See Also:
Cookie.isExpired(Date)
Returns:
true if any cookies were purged./**
     * Removes all of {@link Cookie cookies} in this HTTP state
     * that have expired by the specified {@link java.util.Date date}.
     *
     * @return true if any cookies were purged.
     *
     * @see Cookie#isExpired(Date)
     */
    @Override
    public boolean clearExpired(final Date date) {
        if (date == null) {
            return false;
        }
        lock.writeLock().lock();
        try {
            boolean removed = false;
            for (final Iterator<Cookie> it = cookies.iterator(); it.hasNext(); ) {
                if (it.next().isExpired(date)) {
                    it.remove();
                    removed = true;
                }
            }
            return removed;
        } finally {
            lock.writeLock().unlock();
        }
    }

    
Clears all cookies.
/**
     * Clears all cookies.
     */
    @Override
    public void clear() {
        lock.writeLock().lock();
        try {
            cookies.clear();
        } finally {
            lock.writeLock().unlock();
        }
    }

    @Override
    public String toString() {
        lock.readLock().lock();
        try {
            return cookies.toString();
        } finally {
            lock.readLock().unlock();
        }
    }

}