/****************************************************************
    * 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.jsieve.parser.address;
  
  import java.io.Reader;
  import java.io.StringReader;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Collections;
  
  import org.apache.jsieve.mail.MailAdapter;
  import org.apache.jsieve.mail.MailAdapter.Address;
  import org.apache.jsieve.parser.generated.address.ASTaddr_spec;
  import org.apache.jsieve.parser.generated.address.ASTaddress_list;
  import org.apache.jsieve.parser.generated.address.ASTdomain;
  import org.apache.jsieve.parser.generated.address.ASTlocal_part;
  import org.apache.jsieve.parser.generated.address.AddressListParser;
  import org.apache.jsieve.parser.generated.address.ParseException;
  import org.apache.jsieve.parser.generated.address.Token;
  
  /**
   * Builds <code>MailAdapter.Address</code> from address lists. Note that
   * implementators of {@link MailAdapter} are recommended to use a fully featured
   * and maintained parser such as <a href='http://james.apache.org/mime4j'>Apache
   * Mime4J</a>. This implementation is based on Mime4J code but is intended only
   * for internal and demonstration purposes. It is not actively maintained.
   */
  public class SieveAddressBuilder {
  
      private static final Address[] EMPTY_ADDRESSES = {};
  
      private final Collection<Address> addresses;
  
      private final Worker worker;
  
      public SieveAddressBuilder() {
          addresses = Collections.synchronizedCollection(new ArrayList<Address>());
          worker = new Worker();
      }
  
      /**
       * Clears the addresses currently accumulated.
       */
      public void reset() {
          addresses.clear();
      }
  
      /**
       * Adds addresses in the given list.
       * 
       * @param addressList
       *            RFC822 address list
       * @throws ParseException
       */
      public void addAddresses(String addressList) throws ParseException {
          final StringReader reader = new StringReader(addressList);
          worker.addAddressses(reader, addresses);
      }
  
      /**
       * Gets addresses currently accumulated by calls to
       * {@link #addAddresses(String)} since the last call to {@link #reset}.
       * 
       * @return addresses, not null
       */
      public Address[] getAddresses() {
          final Address[] results = (Address[]) addresses.toArray(EMPTY_ADDRESSES);
          return results;
      }
  
      /**
       * Performs the actual work. Factored into an inner class so that the build
       * interface is clean.
       */
      private final class Worker extends BaseAddressListVisitor {
  
          public void addAddressses(final Reader reader, final Collection results)
                  throws ParseException {
              AddressListParser parser = new AddressListParser(reader);
              ASTaddress_list root = parser.parse();
              root.childrenAccept(this, results);
          }
 
         @SuppressWarnings("unchecked")
         public Object visit(ASTaddr_spec node, Object data) {
             final AddressBean address = new AddressBean();
             node.childrenAccept(this, address);
             if (data instanceof Collection) {
                 final Collection collection = (Collection) data;
                 collection.add(address);
             }
             return data;
         }
 
         public Object visit(final ASTdomain node, final Object data) {
             if (data instanceof AddressBean) {
                 final AddressBean address = (AddressBean) data;
                 final String domain = contents(node);
                 address.setDomain(domain);
             }
             return data;
         }
 
         public Object visit(ASTlocal_part node, Object data) {
             if (data instanceof AddressBean) {
                 final AddressBean address = (AddressBean) data;
                 final String localPart = contents(node);
                 address.setLocalPart(localPart);
             }
             return data;
         }
 
         private String contents(AddressNode node) {
             StringBuffer buffer = new StringBuffer(32);
             Token last = node.lastToken;
             Token next = node.firstToken;
             while (next != last) {
                 buffer.append(next.image);
                 next = next.next;
             }
             buffer.append(last.image);
             return buffer.toString();
         }
     }
 
     /**
      * Bean based address implementation.
      */
     private final class AddressBean implements Address {
         private String localPart;
 
         private String domain;
 
         public AddressBean() {
             localPart = "";
             domain = "";
         }
 
         public String getDomain() {
             return domain;
         }
 
         public void setDomain(String domain) {
             this.domain = domain;
         }
 
         public String getLocalPart() {
             return localPart;
         }
 
         public void setLocalPart(String localPart) {
             this.localPart = localPart;
         }
     }
 }