/*
    * Copyright (C) 2012 Atlassian
    *
    * 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.
   */
  
  package com.atlassian.jira.rest.client.api.domain;
  
  import com.atlassian.jira.rest.client.api.AddressableEntity;
  import com.atlassian.jira.rest.client.api.IdentifiableEntity;
  import com.atlassian.jira.rest.client.api.NamedEntity;
  import com.google.common.base.Function;
  import com.google.common.base.Predicate;
  import com.google.common.collect.Iterables;
  
  import java.util.NoSuchElementException;
  
  /**
   * Helper class for entities.
   *
   * @since v1.0
   */
  public class EntityHelper {
  
      public static Function<IdentifiableEntity<String>, String> GET_ENTITY_STRING_ID_FUNCTION = new Function<IdentifiableEntity<String>, String>() {
          @Override
          public String apply(IdentifiableEntity<String> entity) {
              return entity.getId();
          }
      };
  
      public static Function<NamedEntity, String> GET_ENTITY_NAME_FUNCTION = new Function<NamedEntity, String>() {
          @Override
          public String apply(NamedEntity entity) {
              return entity.getName();
          }
      };
  
      public static Iterable<String> toNamesList(Iterable<? extends NamedEntity> items) {
          return Iterables.transform(items, GET_ENTITY_NAME_FUNCTION);
      }
  
      public static Iterable<String> toFileNamesList(Iterable<? extends Attachment> attachments) {
          return Iterables.transform(attachments, new Function<Attachment, String>() {
              @Override
              public String apply(Attachment a) {
                  return a.getFilename();
              }
          });
      }
  
      @SuppressWarnings("unused")
      public static <T> Iterable<String> toStringIdList(Iterable<IdentifiableEntity<T>> items) {
          return Iterables.transform(items, new Function<IdentifiableEntity<T>, String>() {
              @Override
              public String apply(IdentifiableEntity<T> from) {
                  return from.getId() == null ? null : from.getId().toString();
              }
          });
      }
  
      public static <T extends NamedEntity> T findEntityByName(Iterable<T> entities, final String name) {
          try {
              return Iterables.find(entities, HasNamePredicate.forName(name));
          } catch (NoSuchElementException ex) {
              throw new NoSuchElementException(String.format("Entity with name \"%s\" not found. Entities: %s", name, entities
                      .toString()));
          }
      }
  
      @SuppressWarnings("unused")
      public static <T extends IdentifiableEntity<K>, K> T findEntityById(Iterable<T> entities, final K id) {
          try {
              return Iterables.find(entities, HasIdPredicate.forId(id));
          } catch (NoSuchElementException ex) {
              throw new NoSuchElementException(String.format("Entity with id \"%s\" not found. Entities: %s", id, entities
                      .toString()));
          }
      }
  
      public static <T extends Attachment> T findAttachmentByFileName(Iterable<T> attachments, final String fileName) {
          return Iterables.find(attachments, HasFileNamePredicate.forFileName(fileName));
      }
  
      public static class HasFileNamePredicate<T extends Attachment> implements Predicate<T> {
  
          private final String fileName;
  
          public static <K extends Attachment> HasFileNamePredicate<K> forFileName(String fileName) {
             return new HasFileNamePredicate<K>(fileName);
         }
 
         private HasFileNamePredicate(String fileName) {
             this.fileName = fileName;
         }
 
         @Override
         public boolean apply(T attachment) {
             return fileName.equals(attachment.getFilename());
         }
     }
 
 
     public static class HasNamePredicate<T extends NamedEntity> implements Predicate<T> {
 
         private final String name;
 
         public static <K extends NamedEntity> HasNamePredicate<K> forName(String name) {
             return new HasNamePredicate<K>(name);
         }
 
         private HasNamePredicate(String name) {
             this.name = name;
         }
 
         @Override
         public boolean apply(T input) {
             return name.equals(input.getName());
         }
     }
 
     public static class HasIdPredicate<T extends IdentifiableEntity<K>, K> implements Predicate<T> {
 
         private final K id;
 
         public static <X extends IdentifiableEntity<Y>, Y> HasIdPredicate<X, Y> forId(Y id) {
             return new HasIdPredicate<X, Y>(id);
         }
 
         private HasIdPredicate(K id) {
             this.id = id;
         }
 
         @Override
         public boolean apply(T input) {
             return id.equals(input.getId());
         }
     }
 
     public static class AddressEndsWithPredicate implements Predicate<AddressableEntity> {
 
         private final String stringEnding;
 
         public AddressEndsWithPredicate(String stringEnding) {
             this.stringEnding = stringEnding;
         }
 
         @Override
         public boolean apply(final AddressableEntity input) {
             return input.getSelf().getPath().endsWith(stringEnding);
         }
     }
 }