/**
 * The MIT License (MIT)
 *
 * Copyright (c) 2014-2017 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.rq;

import java.io.IOException;
import java.util.Locale;
import java.util.regex.Pattern;
import lombok.EqualsAndHashCode;
import org.takes.Request;

/**
 * HTTP method parsing.
 *
 * <p>All implementations of this interface must be immutable and thread-safe.
 *
 * @author Yegor Bugayenko (yegor256@gmail.com)
 * @version $Id: dcfcff50ba31708e32121a2f735cd88428db7d24 $
 * @since 0.13.7
 */
public interface RqMethod extends Request {

    /**
     * GET method.
     */
    String GET = "GET";

    /**
     * POST method.
     */
    String POST = "POST";

    /**
     * PUT method.
     */
    String PUT = "PUT";

    /**
     * DELETE method.
     */
    String DELETE = "DELETE";

    /**
     * HEAD method.
     */
    String HEAD = "HEAD";

    /**
     * OPTIONS method.
     */
    String OPTIONS = "OPTIONS";

    /**
     * PATCH method.
     */
    String PATCH = "PATCH";

    /**
     * TRACE method.
     */
    String TRACE = "TRACE";

    /**
     * CONNECT method.
     */
    String CONNECT = "CONNECT";

    /**
     * Get method.
     * @return HTTP method
     * @throws IOException If fails
     */
    String method() throws IOException;

    /**
     * Request decorator, for HTTP method parsing.
     *
     * <p>The class is immutable and thread-safe.
     *
     * @author Dmitry Zaytsev (dmitry.zaytsev@gmail.com)
     * @version $Id: dcfcff50ba31708e32121a2f735cd88428db7d24 $
     * @since 0.13.7
     */
    @EqualsAndHashCode(callSuper = true)
    final class Base extends RqWrap implements RqMethod {

        /**
         * HTTP token separators which are not already excluded by PATTERN.
         */
        private static final Pattern SEPARATORS = Pattern.compile(
            "[()<>@,;:\\\"/\\[\\]?={}]"
        );

        /**
         * Ctor.
         * @param req Original request
         */
        public Base(final Request req) {
            super(req);
        }

        @Override
        public String method() throws IOException {
            final String method = new RqRequestLine.Base(this)
                .method();
            if (SEPARATORS.matcher(method).find()) {
                throw new IOException(
                    String.format("Invalid HTTP method: %s", method)
                );
            }
            return method.toUpperCase(Locale.ENGLISH);
        }
    }
}