/*
    * 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.giraph.bsp;
  
  import org.apache.giraph.conf.ImmutableClassesGiraphConfiguration;
  import org.apache.hadoop.io.Text;
  import org.apache.hadoop.mapreduce.JobContext;
  import org.apache.hadoop.mapreduce.OutputCommitter;
  import org.apache.hadoop.mapreduce.OutputFormat;
  import org.apache.hadoop.mapreduce.RecordWriter;
  import org.apache.hadoop.mapreduce.TaskAttemptContext;
  import org.apache.log4j.Logger;
  
  import java.io.IOException;
  
  /**
   * This is for internal use only.  Allows the vertex output format routines
   * to be called as if a normal Hadoop job.
   */
  public class BspOutputFormat extends OutputFormat<Text, Text> {
    /** Class logger */
    private static Logger LOG = Logger.getLogger(BspOutputFormat.class);
  
    @Override
    public void checkOutputSpecs(JobContext context)
      throws IOException, InterruptedException {
      ImmutableClassesGiraphConfiguration conf =
          new ImmutableClassesGiraphConfiguration(context.getConfiguration());
      if (!conf.hasVertexOutputFormat() && !conf.hasEdgeOutputFormat()) {
        LOG.warn("checkOutputSpecs: ImmutableOutputCommiter" +
            " will not check anything");
        return;
      }
  
      if (conf.hasVertexOutputFormat()) {
        conf.createWrappedVertexOutputFormat().checkOutputSpecs(context);
      }
      if (conf.hasEdgeOutputFormat()) {
        conf.createWrappedEdgeOutputFormat().checkOutputSpecs(context);
      }
    }
  
    @Override
    public OutputCommitter getOutputCommitter(TaskAttemptContext context)
      throws IOException, InterruptedException {
      ImmutableClassesGiraphConfiguration conf =
          new ImmutableClassesGiraphConfiguration(context.getConfiguration());
      if (!conf.hasVertexOutputFormat() && !conf.hasEdgeOutputFormat()) {
        LOG.warn("getOutputCommitter: Returning " +
            "ImmutableOutputCommiter (does nothing).");
        return new ImmutableOutputCommitter();
      }
  
      if (conf.hasVertexOutputFormat()) {
        return conf.createWrappedVertexOutputFormat().getOutputCommitter(context);
      } else {
        return conf.createWrappedEdgeOutputFormat().getOutputCommitter(context);
      }
    }
  
    @Override
    public RecordWriter<Text, Text> getRecordWriter(TaskAttemptContext context)
      throws IOException, InterruptedException {
      return new BspRecordWriter();
    }
  }