/*
    * #%L
    * SimpleMongoIteratorImpl.java - mongodb-async-driver - Allanbank Consulting, Inc.
    * %%
    * Copyright (C) 2011 - 2014 Allanbank Consulting, Inc.
    * %%
    * 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.
   * #L%
   */
  package com.allanbank.mongodb.client;
  
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Iterator;
  import java.util.List;
  
  import com.allanbank.mongodb.MongoIterator;
  import com.allanbank.mongodb.bson.Document;
  
  /**
   * Iterator over the results of fixed collection.
   * 
   * @param <T>
   *            The type being iterated.
   * 
   * @api.no This class is <b>NOT</b> part of the drivers API. This class may be
   *         mutated in incompatible ways between any two releases of the driver.
   * @copyright 2011-2013, Allanbank Consulting, Inc., All Rights Reserved
   */
  public class SimpleMongoIteratorImpl<T> implements MongoIterator<T> {
  
      /** The wrapped iterator. */
      private final Iterator<T> myIterator;
  
      /**
       * Create a new SimpleMongoIteratorImpl.
       * 
       * @param wrapped
       *            The collection to turn into a {@link MongoIterator}.
       */
      public SimpleMongoIteratorImpl(final Collection<T> wrapped) {
          myIterator = wrapped.iterator();
      }
  
      /**
       * {@inheritDoc}
       * <p>
       * Overridden to return the null as this cursor cannot be restarted.
       * </p>
       */
      @Override
      public Document asDocument() {
          return null;
      }
  
      /**
       * {@inheritDoc}
       * <p>
       * Overridden to do nothing.
       * </p>
       */
      @Override
      public void close() {
          // Nothing.
      }
  
      /**
       * {@inheritDoc}
       * <p>
       * Overridden to return -1.
       * </p>
       */
      @Override
      public int getBatchSize() {
          return -1;
      }
  
      /**
       * {@inheritDoc}
       * <p>
       * Overridden to return true if there are more documents.
       * </p>
       */
      @Override
      public boolean hasNext() {
          return myIterator.hasNext();
      }
  
      /**
      * {@inheritDoc}
      * <p>
      * Overridden to return this iterator.
      * </p>
      */
     @Override
     public Iterator<T> iterator() {
         return this;
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to return the next document from the query.
      * </p>
      * 
      * @see java.util.Iterator#next()
      */
     @Override
     public T next() {
         return myIterator.next();
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to throw an {@link UnsupportedOperationException}.
      * </p>
      * 
      * @see java.util.Iterator#remove()
      */
     @Override
     public void remove() {
         throw new UnsupportedOperationException(
                 "Cannot remove a document via a MongoDB iterator.");
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to do nothing as this iterator only supports single batch
      * results.
      * </p>
      */
     @Override
     public void setBatchSize(final int batchSize) {
         // Nothing.
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to do nothing as this iterator only supports single batch
      * results.
      * </p>
      */
     @Override
     public void stop() {
         // Nothing.
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to return the remaining elements as a array.
      * </p>
      */
     @Override
     public Object[] toArray() {
         final List<T> remaining = toList();
 
         return remaining.toArray();
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to return the remaining elements as a array.
      * </p>
      */
     @Override
     public <S> S[] toArray(final S[] to) {
         final List<T> remaining = toList();
 
         return remaining.toArray(to);
     }
 
     /**
      * {@inheritDoc}
      * <p>
      * Overridden to return the remaining elements as a list.
      * </p>
      */
     @Override
     public List<T> toList() {
         final List<T> remaining = new ArrayList<T>();
 
         while (hasNext()) {
             remaining.add(next());
         }
 
         return remaining;
     }
 }