yegor256/takes

/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2014-2024 Yegor Bugayenko
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
package org.takes.misc;

import java.text.SimpleDateFormat;
import java.util.Locale;
import java.util.TimeZone;

/**
 * Expiration date in GMT.
 *
 * @since 2.0
 */
public interface Expires {

    /**
     * String representation of expiration time.
     * @return Representation of expirate time.
     */
    String print();

    /**
     * Never expires.
     *
     * @since 2.0
     */
    final class Never implements Expires {

        /**
         * Original time.
         */
        private final Expires origin;

        /**
         * Constructor.
         */
        Never() {
            this.origin = new Date(0L);
        }

        @Override
        public String print() {
            return this.origin.print();
        }
    }

    /**
     * Already expired. Returns "0" according to RFC7234.
     *
     * @since 2.0
     */
    final class Expired implements Expires {
        @Override
        public String print() {
            return "Expires=0";
        }
    }

    /**
     * Expires in one hour of the given time.
     *
     * @since 2.0
     */
    final class Hour implements Expires {

        /**
         * Original time.
         */
        private final Expires origin;

        /**
         * Constructor.
         * @param origin Original time
         */
        Hour(final Expires origin) {
            this.origin = origin;
        }

        @Override
        public String print() {
            return this.origin.print();
        }
    }

    /**
     * Expiration date in GMT.
     *
     * @since 2.0
     */
    final class Date implements Expires {

        /**
         * DateFormat for expiration.
         */
        private final ThreadLocal<SimpleDateFormat> format;

        /**
         * Expires date.
         */
        private final java.util.Date expires;

        /**
         * Ctor.
         *
         * <p>Will create instance with default format pattern.</p>
         * @param expiration Expiration in millis
         */
        public Date(final long expiration) {
            this("'Expires='EEE, dd MMM yyyy HH:mm:ss z", expiration);
        }

        /**
         * Ctor.
         * @param ptn Date format pattern
         * @param expiration Expiration in millis
         */
        public Date(final String ptn, final long expiration) {
            this(ptn, Locale.ENGLISH, expiration);
        }

        /**
         * Ctor.
         * @param ptn Date format pattern
         * @param locale Locale
         * @param expiration Expiration in millis
         */
        public Date(final String ptn, final Locale locale,
            final long expiration) {
            this(ptn, locale, new java.util.Date(expiration));
        }

        /**
         * Ctor.
         * @param ptn Date format pattern
         * @param locale Locale
         * @param expires Date when expires
         */
        public Date(final String ptn, final Locale locale,
            final java.util.Date expires) {
            this.format = ThreadLocal.withInitial(
                () -> new SimpleDateFormat(ptn, locale)
            );
            this.expires = new java.util.Date(expires.getTime());
        }

        @Override
        public String print() {
            final SimpleDateFormat fmt = this.format.get();
            fmt.setTimeZone(TimeZone.getTimeZone("GMT"));
            return fmt.format(this.expires);
        }
    }
}