/**
    * Licensed to jclouds, Inc. (jclouds) under one or more
    * contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  jclouds 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.jclouds.compute.predicates;
  
  import static com.google.common.base.Preconditions.checkNotNull;
  
  import java.util.Set;
  
  import org.jclouds.javax.annotation.Nullable;
  
  import org.jclouds.compute.domain.Image;
  
  import com.google.common.base.Predicate;
  import com.google.common.base.Predicates;
  import com.google.common.collect.Sets;
  
  /**
   * Container for image filters (predicates).
   * 
   * This class has static methods that create customized predicates to use with
   * {@link org.jclouds.compute.ComputeService}.
   * 
   * @author Adrian Cole
   */
  public class ImagePredicates {
     private static final class Is64BitPredicate implements Predicate<Image> {
        @Override
        public boolean apply(Image image) {
           return image.getOperatingSystem().is64Bit();
        }
  
        @Override
        public String toString() {
           return "is64Bit()";
        }
  
        @Override
        public boolean equals(@Nullable Object obj) {
           return (obj instanceof Is64BitPredicate);
        }
  
     }
  
     /**
      * evaluates true if the Image id is in the supplied set
      * 
      * @param ids
      *           ids of the images
      * @return predicate
      */
     public static Predicate<Image> idIn(Iterable<String> ids) {
        checkNotNull(ids, "ids must be defined");
        final Set<String> search = Sets.newHashSet(ids);
        return new Predicate<Image>() {
           @Override
           public boolean apply(Image image) {
              return search.contains(image.getId());
           }
  
           @Override
           public String toString() {
              return "idIn(" + search + ")";
           }
        };
     }
     
     /**
      * evaluates true if the Image metadata contains the following values
      * 
      * @param key
      *           key in Image#getUserMetadata
      * @param value
      *           value in Image#getUserMetadata
       * @return predicate
      */
     public static Predicate<Image> userMetadataContains(final String key, final String value) {
        checkNotNull(key, "key must be defined");
        checkNotNull(value, "value must be defined");
        return new Predicate<Image>() {
           @Override
           public boolean apply(Image image) {
              return value.equals(image.getUserMetadata().get(key));
           }
 
          @Override
          public String toString() {
             return "metadataContains(" + key +", "+value + ")";
          }
       };
    }
 
    /**
     * evaluates true if the Image
     * 
     * @param ids
     *           ids of the images
     * @return predicate
     */
    public static Predicate<Image> idEquals(final String id) {
       checkNotNull(id, "id must be defined");
       return new Predicate<Image>() {
          @Override
          public boolean apply(Image image) {
             return id.equals(image.getId());
          }
 
          @Override
          public String toString() {
             return "idEquals(" + id + ")";
          }
       };
    }
 
    /**
     * return true if this is a 64bit image.
     */
    public static Predicate<Image> is64Bit() {
       return new Is64BitPredicate();
    }
 
    /**
     * return everything.
     */
    public static Predicate<Image> any() {
       return Predicates.<Image> alwaysTrue();
    }
 
 }