/*
    * Copyright 2015 The Netty Project
    *
    * The Netty Project 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 io.netty.handler.codec.http.cookie;
  
  import static io.netty.handler.codec.http.cookie.CookieUtil.firstInvalidCookieNameOctet;
  import static io.netty.handler.codec.http.cookie.CookieUtil.firstInvalidCookieValueOctet;
  import static io.netty.handler.codec.http.cookie.CookieUtil.unwrapValue;
  
  import java.nio.CharBuffer;
  
  import io.netty.util.internal.logging.InternalLogger;
  import io.netty.util.internal.logging.InternalLoggerFactory;
  
  /**
   * Parent of Client and Server side cookie decoders
   */
  public abstract class CookieDecoder {
  
      private final InternalLogger logger = InternalLoggerFactory.getInstance(getClass());
  
      private final boolean strict;
  
      protected CookieDecoder(boolean strict) {
          this.strict = strict;
      }
  
      protected DefaultCookie initCookie(String header, int nameBegin, int nameEnd, int valueBegin, int valueEnd) {
          if (nameBegin == -1 || nameBegin == nameEnd) {
              logger.debug("Skipping cookie with null name");
              return null;
          }
  
          if (valueBegin == -1) {
              logger.debug("Skipping cookie with null value");
              return null;
          }
  
          CharSequence wrappedValue = CharBuffer.wrap(header, valueBegin, valueEnd);
          CharSequence unwrappedValue = unwrapValue(wrappedValue);
          if (unwrappedValue == null) {
              logger.debug("Skipping cookie because starting quotes are not properly balanced in '{}'",
                      wrappedValue);
              return null;
          }
  
          final String name = header.substring(nameBegin, nameEnd);
  
          int invalidOctetPos;
          if (strict && (invalidOctetPos = firstInvalidCookieNameOctet(name)) >= 0) {
              if (logger.isDebugEnabled()) {
                  logger.debug("Skipping cookie because name '{}' contains invalid char '{}'",
                          name, name.charAt(invalidOctetPos));
              }
              return null;
          }
  
          final boolean wrap = unwrappedValue.length() != valueEnd - valueBegin;
  
          if (strict && (invalidOctetPos = firstInvalidCookieValueOctet(unwrappedValue)) >= 0) {
              if (logger.isDebugEnabled()) {
                  logger.debug("Skipping cookie because value '{}' contains invalid char '{}'",
                          unwrappedValue, unwrappedValue.charAt(invalidOctetPos));
              }
              return null;
          }
  
          DefaultCookie cookie = new DefaultCookie(name, unwrappedValue.toString());
          cookie.setWrap(wrap);
          return cookie;
      }
  }