/*
 *  Copyright 1999-2004 The Apache Software Foundation
 *
 *  Licensed 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 class was originally written by Jason Hunter 
 * as part of the book "Java Servlet Programming" (O'Reilly).  
 * See http://www.servlets.com/book for more information.
 * Used by Sun Microsystems with permission.
 *
 */

package org.apache.tomcat.util.http;

import java.util.*;

/** 
 * A mapping to determine the (somewhat arbitrarily) preferred charset for 
 * a given locale.  Supports all locales recognized in JDK 1.1.
 * This class was originally written by Jason Hunter [jhunter@acm.org]
 * as part of the book "Java Servlet Programming" (O'Reilly).
 * See 
 * http://www.servlets.com/book for more information.
 * Used by Sun Microsystems with permission.
 */
public class LocaleToCharsetMap {

  private static Hashtable map;

  static {
    map = new Hashtable();

    map.put("ar", "ISO-8859-6");
    map.put("be", "ISO-8859-5");
    map.put("bg", "ISO-8859-5");
    map.put("ca", "ISO-8859-1");
    map.put("cs", "ISO-8859-2");
    map.put("da", "ISO-8859-1");
    map.put("de", "ISO-8859-1");
    map.put("el", "ISO-8859-7");
    map.put("en", "ISO-8859-1");
    map.put("es", "ISO-8859-1");
    map.put("et", "ISO-8859-1");
    map.put("fi", "ISO-8859-1");
    map.put("fr", "ISO-8859-1");
    map.put("hr", "ISO-8859-2");
    map.put("hu", "ISO-8859-2");
    map.put("is", "ISO-8859-1");
    map.put("it", "ISO-8859-1");
    map.put("iw", "ISO-8859-8");
    map.put("ja", "Shift_JIS");
    map.put("ko", "EUC-KR");     // Requires JDK 1.1.6
    map.put("lt", "ISO-8859-2");
    map.put("lv", "ISO-8859-2");
    map.put("mk", "ISO-8859-5");
    map.put("nl", "ISO-8859-1");
    map.put("no", "ISO-8859-1");
    map.put("pl", "ISO-8859-2");
    map.put("pt", "ISO-8859-1");
    map.put("ro", "ISO-8859-2");
    map.put("ru", "ISO-8859-5");
    map.put("sh", "ISO-8859-5");
    map.put("sk", "ISO-8859-2");
    map.put("sl", "ISO-8859-2");
    map.put("sq", "ISO-8859-2");
    map.put("sr", "ISO-8859-5");
    map.put("sv", "ISO-8859-1");
    map.put("tr", "ISO-8859-9");
    map.put("uk", "ISO-8859-5");
    map.put("zh", "GB2312");
    map.put("zh_TW", "Big5");

  }

  /**
   * Gets the preferred charset for the given locale, or null if the locale
   * is not recognized.
   *
   * @param loc the locale
   * @return the preferred charset
   */
  public static String getCharset(Locale loc) {
    String charset;

    // Try for an full name match (may include country)
    charset = (String) map.get(loc.toString());
    if (charset != null) return charset;

    // If a full name didn't match, try just the language
    charset = (String) map.get(loc.getLanguage());
    return charset;  // may be null
  }
}