/*
 *  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.
 */
package org.apache.coyote;

import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;

/**
 * Constants.
 */
public final class Constants {

    /**
     * Default URI character encoding.
     */
    public static final Charset DEFAULT_URI_CHARSET = StandardCharsets.UTF_8;

    /**
     * Default body character encoding.
     */
    public static final Charset DEFAULT_BODY_CHARSET = StandardCharsets.ISO_8859_1;

    /**
     * Maximum number of notes.
     */
    public static final int MAX_NOTES = 32;


    // Request states

    /**
     * Request state: new request.
     */
    public static final int STAGE_NEW = 0;

    /**
     * Request state: parsing request.
     */
    public static final int STAGE_PARSE = 1;

    /**
     * Request state: preparing request.
     */
    public static final int STAGE_PREPARE = 2;

    /**
     * Request state: servicing request.
     */
    public static final int STAGE_SERVICE = 3;

    /**
     * Request state: end input.
     */
    public static final int STAGE_ENDINPUT = 4;

    /**
     * Request state: end output.
     */
    public static final int STAGE_ENDOUTPUT = 5;

    /**
     * Request state: keep-alive.
     */
    public static final int STAGE_KEEPALIVE = 6;

    /**
     * Request state: ended.
     */
    public static final int STAGE_ENDED = 7;

    // Default protocol settings

    /**
     * Default connection linger time.
     */
    public static final int DEFAULT_CONNECTION_LINGER = -1;

    /**
     * Default TCP no-delay setting.
     */
    public static final boolean DEFAULT_TCP_NO_DELAY = true;

    /**
     * Has security been turned on?
     */
    public static final boolean IS_SECURITY_ENABLED = (System.getSecurityManager() != null);


    /**
     * The request attribute that is set to the value of {@code Boolean.TRUE} if connector processing this request
     * supports use of sendfile.
     */
    public static final String SENDFILE_SUPPORTED_ATTR = "org.apache.tomcat.sendfile.support";


    /**
     * The request attribute that can be used by a servlet to pass to the connector the name of the file that is to be
     * served by sendfile. The value should be {@code String} that is {@code File.getCanonicalPath()} of the file to be
     * served.
     */
    public static final String SENDFILE_FILENAME_ATTR = "org.apache.tomcat.sendfile.filename";


    /**
     * The request attribute that can be used by a servlet to pass to the connector the start offset of the part of a
     * file that is to be served by sendfile. The value should be {@code java.lang.Long}. To serve complete file the
     * value should be {@code Long.valueOf(0)}.
     */
    public static final String SENDFILE_FILE_START_ATTR = "org.apache.tomcat.sendfile.start";


    /**
     * The request attribute that can be used by a servlet to pass to the connector the end offset (not including) of
     * the part of a file that is to be served by sendfile. The value should be {@code java.lang.Long}. To serve
     * complete file the value should be equal to the length of the file.
     */
    public static final String SENDFILE_FILE_END_ATTR = "org.apache.tomcat.sendfile.end";


    /**
     * The request attribute set by the RemoteIpFilter, RemoteIpValve (and may be set by other similar components) that
     * identifies for the connector the remote IP address claimed to be associated with this request when a request is
     * received via one or more proxies. It is typically provided via the X-Forwarded-For HTTP header.
     */
    public static final String REMOTE_ADDR_ATTRIBUTE = "org.apache.tomcat.remoteAddr";

    /**
     * The request attribute set by the RemoteIpFilter, RemoteIpValve (and may be set by other similar components) that
     * identifies for the connector the connection peer IP address.
     */
    public static final String PEER_ADDR_ATTRIBUTE = "org.apache.tomcat.peerAddr";

    /**
     * Private constructor to prevent instantiation.
     */
    private Constants() {
        // Hide default constructor
    }
}
