// Copyright 2009 Google 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.

package com.google.enterprise.connector.pusher;

import com.google.enterprise.connector.instantiator.DocumentFilterFactoryFactory;
import com.google.enterprise.connector.instantiator.DocumentFilterFactoryFactoryImpl;
import com.google.enterprise.connector.traversal.FileSizeLimitInfo;

import java.util.logging.Logger;

/**
 * Factory that creates {@link DocPusher} instances that feed
 * {@link FeedConnection}.
 */
// TODO: Support multiple sinks where different connector instances
// might feed different sinks.
public class DocPusherFactory implements PusherFactory {

  private static final Logger LOGGER =
      Logger.getLogger(DocPusherFactory.class.getName());

  /**
   * FeedConnection that is the sink for our generated XmlFeeds.
   */
  private final FeedConnection feedConnection;

  /**
   * Configured maximum document size and maximum feed file size supported.
   */
  private final FileSizeLimitInfo fileSizeLimit;

  /**
   * The {@link DocumentFilterFactoryFactory} is used to construct
   * {@code Document} instances that act as filters on a source
   * document.  Document filters may add, remove, or modify
   * {@code Properties}.  The DocumentFilterFactoryFactory set here
   * typically creates a {@link DocumentFilterChain} - a chain of
   * DocumentFilterFactories that is used to construct a
   * Document manipulation pipeline.
   */
  private final DocumentFilterFactoryFactory documentFilterFactoryFactory;

  /**
   * Creates a {@code DocPusherFactory} object from the specified
   * {@code feedConnection}.  This constructor is Used by the tests.
   *
   * @param feedConnection a FeedConnection
   */
  public DocPusherFactory(FeedConnection feedConnection) {
    this(feedConnection, new FileSizeLimitInfo(),
         new DocumentFilterFactoryFactoryImpl(null, null));
  }

  /**
   * Creates a {@code DocPusherFactory} object from the specified
   * {@code feedConnection}.  The supplied {@link FileSizeLimitInfo} specifies
   * constraints as to the size of a Document's content and the size of
   * generated Feed files.
   *
   * @param feedConnection a {@link FeedConnection} sink for documents.
   * @param fileSizeLimit {@link FileSizeLimitInfo} constraints on document
   *        content and feed size.
   * @param documentFilterFactoryFactory a {@link DocumentFilterFactoryFactory}
   *        that will be used to create document processing filters.
   */
  public DocPusherFactory(FeedConnection feedConnection,
      FileSizeLimitInfo fileSizeLimit,
      DocumentFilterFactoryFactory documentFilterFactoryFactory) {
    this.feedConnection = feedConnection;
    this.fileSizeLimit = fileSizeLimit;
    this.documentFilterFactoryFactory = documentFilterFactoryFactory;

    LOGGER.config(feedConnection.toString());
    LOGGER.config(fileSizeLimit.toString());
    LOGGER.config(documentFilterFactoryFactory.toString());
  }

  @Override
  public Pusher newPusher(String dataSource) {
    return new DocPusher(feedConnection, dataSource, fileSizeLimit,
        documentFilterFactoryFactory.getDocumentFilterFactory(dataSource));
  }
}