/*
    * ====================================================================
    * 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;
  
  import java.util.Locale;
  
  import org.apache.http.HttpStatus;
  import org.apache.http.ReasonPhraseCatalog;
  import org.apache.http.annotation.Immutable;
  import org.apache.http.util.Args;
  
  /**
   * English reason phrases for HTTP status codes.
   * All status codes defined in RFC1945 (HTTP/1.0), RFC2616 (HTTP/1.1), and
   * RFC2518 (WebDAV) are supported.
   *
   * @since 4.0
   */
  @Immutable
  public class EnglishReasonPhraseCatalog implements ReasonPhraseCatalog {
  
      // static array with english reason phrases defined below
  
      /**
       * The default instance of this catalog.
       * This catalog is thread safe, so there typically
       * is no need to create other instances.
       */
      public final static EnglishReasonPhraseCatalog INSTANCE =
          new EnglishReasonPhraseCatalog();
  
  
      /**
       * Restricted default constructor, for derived classes.
       * If you need an instance of this class, use {@link #INSTANCE INSTANCE}.
       */
      protected EnglishReasonPhraseCatalog() {
          // no body
      }
  
  
      /**
       * Obtains the reason phrase for a status code.
       *
       * @param status    the status code, in the range 100-599
       * @param loc       ignored
       *
       * @return  the reason phrase, or <code>null</code>
       */
      public String getReason(final int status, final Locale loc) {
          Args.check(status >= 100 && status < 600, "Unknown category for status code " + status);
          final int category = status / 100;
          final int subcode  = status - 100*category;
  
          String reason = null;
          if (REASON_PHRASES[category].length > subcode) {
              reason = REASON_PHRASES[category][subcode];
          }
  
          return reason;
      }
  
  
      /** Reason phrases lookup table. */
      private static final String[][] REASON_PHRASES = new String[][]{
          null,
          new String[3],  // 1xx
          new String[8],  // 2xx
          new String[8],  // 3xx
          new String[25], // 4xx
          new String[8]   // 5xx
      };
  
  
 
     /**
      * Stores the given reason phrase, by status code.
      * Helper method to initialize the static lookup table.
      *
      * @param status    the status code for which to define the phrase
      * @param reason    the reason phrase for this status code
      */
     private static void setReason(final int status, final String reason) {
         final int category = status / 100;
         final int subcode  = status - 100*category;
         REASON_PHRASES[category][subcode] = reason;
     }
 
 
     // ----------------------------------------------------- Static Initializer
 
     /** Set up status code to "reason phrase" map. */
     static {
         // HTTP 1.0 Server status codes -- see RFC 1945
         setReason(HttpStatus.SC_OK,
                   "OK");
         setReason(HttpStatus.SC_CREATED,
                   "Created");
         setReason(HttpStatus.SC_ACCEPTED,
                   "Accepted");
         setReason(HttpStatus.SC_NO_CONTENT,
                   "No Content");
         setReason(HttpStatus.SC_MOVED_PERMANENTLY,
                   "Moved Permanently");
         setReason(HttpStatus.SC_MOVED_TEMPORARILY,
                   "Moved Temporarily");
         setReason(HttpStatus.SC_NOT_MODIFIED,
                   "Not Modified");
         setReason(HttpStatus.SC_BAD_REQUEST,
                   "Bad Request");
         setReason(HttpStatus.SC_UNAUTHORIZED,
                   "Unauthorized");
         setReason(HttpStatus.SC_FORBIDDEN,
                   "Forbidden");
         setReason(HttpStatus.SC_NOT_FOUND,
                   "Not Found");
         setReason(HttpStatus.SC_INTERNAL_SERVER_ERROR,
                   "Internal Server Error");
         setReason(HttpStatus.SC_NOT_IMPLEMENTED,
                   "Not Implemented");
         setReason(HttpStatus.SC_BAD_GATEWAY,
                   "Bad Gateway");
         setReason(HttpStatus.SC_SERVICE_UNAVAILABLE,
                   "Service Unavailable");
 
         // HTTP 1.1 Server status codes -- see RFC 2048
         setReason(HttpStatus.SC_CONTINUE,
                   "Continue");
         setReason(HttpStatus.SC_TEMPORARY_REDIRECT,
                   "Temporary Redirect");
         setReason(HttpStatus.SC_METHOD_NOT_ALLOWED,
                   "Method Not Allowed");
         setReason(HttpStatus.SC_CONFLICT,
                   "Conflict");
         setReason(HttpStatus.SC_PRECONDITION_FAILED,
                   "Precondition Failed");
         setReason(HttpStatus.SC_REQUEST_TOO_LONG,
                   "Request Too Long");
         setReason(HttpStatus.SC_REQUEST_URI_TOO_LONG,
                   "Request-URI Too Long");
         setReason(HttpStatus.SC_UNSUPPORTED_MEDIA_TYPE,
                   "Unsupported Media Type");
         setReason(HttpStatus.SC_MULTIPLE_CHOICES,
                   "Multiple Choices");
         setReason(HttpStatus.SC_SEE_OTHER,
                   "See Other");
         setReason(HttpStatus.SC_USE_PROXY,
                   "Use Proxy");
         setReason(HttpStatus.SC_PAYMENT_REQUIRED,
                   "Payment Required");
         setReason(HttpStatus.SC_NOT_ACCEPTABLE,
                   "Not Acceptable");
         setReason(HttpStatus.SC_PROXY_AUTHENTICATION_REQUIRED,
                   "Proxy Authentication Required");
         setReason(HttpStatus.SC_REQUEST_TIMEOUT,
                   "Request Timeout");
 
         setReason(HttpStatus.SC_SWITCHING_PROTOCOLS,
                   "Switching Protocols");
         setReason(HttpStatus.SC_NON_AUTHORITATIVE_INFORMATION,
                   "Non Authoritative Information");
         setReason(HttpStatus.SC_RESET_CONTENT,
                   "Reset Content");
         setReason(HttpStatus.SC_PARTIAL_CONTENT,
                   "Partial Content");
         setReason(HttpStatus.SC_GATEWAY_TIMEOUT,
                   "Gateway Timeout");
         setReason(HttpStatus.SC_HTTP_VERSION_NOT_SUPPORTED,
                   "Http Version Not Supported");
         setReason(HttpStatus.SC_GONE,
                   "Gone");
         setReason(HttpStatus.SC_LENGTH_REQUIRED,
                   "Length Required");
         setReason(HttpStatus.SC_REQUESTED_RANGE_NOT_SATISFIABLE,
                   "Requested Range Not Satisfiable");
         setReason(HttpStatus.SC_EXPECTATION_FAILED,
                   "Expectation Failed");
 
         // WebDAV Server-specific status codes
         setReason(HttpStatus.SC_PROCESSING,
                   "Processing");
         setReason(HttpStatus.SC_MULTI_STATUS,
                   "Multi-Status");
         setReason(HttpStatus.SC_UNPROCESSABLE_ENTITY,
                   "Unprocessable Entity");
         setReason(HttpStatus.SC_INSUFFICIENT_SPACE_ON_RESOURCE,
                   "Insufficient Space On Resource");
         setReason(HttpStatus.SC_METHOD_FAILURE,
                   "Method Failure");
         setReason(HttpStatus.SC_LOCKED,
                   "Locked");
         setReason(HttpStatus.SC_INSUFFICIENT_STORAGE,
                   "Insufficient Storage");
         setReason(HttpStatus.SC_FAILED_DEPENDENCY,
                   "Failed Dependency");
     }
 
 
 }