/*
    * ====================================================================
    * 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.message;
  
  import org.apache.http.HeaderElement;
  import org.apache.http.NameValuePair;
  import org.apache.http.annotation.NotThreadSafe;
  import org.apache.http.util.LangUtils;
  
  /**
   * Basic implementation of {@link HeaderElement}
   *
   * @since 4.0
   */
  @NotThreadSafe
  public class BasicHeaderElement implements HeaderElement, Cloneable {
  
      private final String name;
      private final String value;
      private final NameValuePair[] parameters;
  
      /**
       * Constructor with name, value and parameters.
       *
       * @param name header element name
       * @param value header element value. May be <tt>null</tt>
       * @param parameters header element parameters. May be <tt>null</tt>.
       *   Parameters are copied by reference, not by value
       */
      public BasicHeaderElement(
              final String name,
              final String value,
              final NameValuePair[] parameters) {
          super();
          if (name == null) {
              throw new IllegalArgumentException("Name may not be null");
          }
          this.name = name;
          this.value = value;
          if (parameters != null) {
              this.parameters = parameters;
          } else {
              this.parameters = new NameValuePair[] {};
          }
      }
  
      /**
       * Constructor with name and value.
       *
       * @param name header element name
       * @param value header element value. May be <tt>null</tt>
       */
      public BasicHeaderElement(final String name, final String value) {
         this(name, value, null);
      }
  
      public String getName() {
          return this.name;
      }
  
      public String getValue() {
          return this.value;
      }
  
      public NameValuePair[] getParameters() {
          return this.parameters.clone();
      }
  
      public int getParameterCount() {
          return this.parameters.length;
      }
  
      public NameValuePair getParameter(int index) {
          // ArrayIndexOutOfBoundsException is appropriate
         return this.parameters[index];
     }
 
     public NameValuePair getParameterByName(final String name) {
         if (name == null) {
             throw new IllegalArgumentException("Name may not be null");
         }
         NameValuePair found = null;
         for (int i = 0; i < this.parameters.length; i++) {
             NameValuePair current = this.parameters[ i ];
             if (current.getName().equalsIgnoreCase(name)) {
                 found = current;
                 break;
             }
         }
         return found;
     }
 
     @Override
     public boolean equals(final Object object) {
         if (this == object) return true;
         if (object instanceof HeaderElement) {
             BasicHeaderElement that = (BasicHeaderElement) object;
             return this.name.equals(that.name)
                 && LangUtils.equals(this.value, that.value)
                 && LangUtils.equals(this.parameters, that.parameters);
         } else {
             return false;
         }
     }
 
     @Override
     public int hashCode() {
         int hash = LangUtils.HASH_SEED;
         hash = LangUtils.hashCode(hash, this.name);
         hash = LangUtils.hashCode(hash, this.value);
         for (int i = 0; i < this.parameters.length; i++) {
             hash = LangUtils.hashCode(hash, this.parameters[i]);
         }
         return hash;
     }
 
     @Override
     public String toString() {
         StringBuilder buffer = new StringBuilder();
         buffer.append(this.name);
         if (this.value != null) {
             buffer.append("=");
             buffer.append(this.value);
         }
         for (int i = 0; i < this.parameters.length; i++) {
             buffer.append("; ");
             buffer.append(this.parameters[i]);
         }
         return buffer.toString();
     }
 
     @Override
     public Object clone() throws CloneNotSupportedException {
         // parameters array is considered immutable
         // no need to make a copy of it
         return super.clone();
     }
 
 }