/**
 * 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.sqoop.mapreduce;

import com.cloudera.sqoop.manager.ConnManager;
import com.cloudera.sqoop.manager.ExportJobContext;
import com.cloudera.sqoop.mapreduce.ExportJobBase;
import com.cloudera.sqoop.mapreduce.db.DBConfiguration;
import com.cloudera.sqoop.mapreduce.db.DBOutputFormat;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.io.DefaultStringifier;
import org.apache.hadoop.io.MapWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.InputFormat;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.OutputFormat;
import org.apache.sqoop.mapreduce.hcat.SqoopHCatUtilities;
import org.kitesdk.data.mapreduce.DatasetKeyInputFormat;

import java.io.IOException;
import java.util.Map;
import org.apache.sqoop.util.FileSystemUtil;

/**
 * Run an export using JDBC (JDBC-based ExportOutputFormat).
 */
public class JdbcExportJob extends ExportJobBase {

  private FileType fileType;

  public static final Log LOG = LogFactory.getLog(
      JdbcExportJob.class.getName());

  public JdbcExportJob(final ExportJobContext context) {
    super(context);
  }

  public JdbcExportJob(final ExportJobContext ctxt,
      final Class<? extends Mapper> mapperClass,
      final Class<? extends InputFormat> inputFormatClass,
      final Class<? extends OutputFormat> outputFormatClass) {
    super(ctxt, mapperClass, inputFormatClass, outputFormatClass);
  }

  @Override
  protected void configureInputFormat(Job job, String tableName,
      String tableClassName, String splitByCol)
      throws ClassNotFoundException, IOException {

    fileType = getInputFileType();

    super.configureInputFormat(job, tableName, tableClassName, splitByCol);

    if (isHCatJob) {
      SqoopHCatUtilities.configureExportInputFormat(options, job,
        context.getConnManager(), tableName, job.getConfiguration());
      return;
    } else if (fileType == FileType.AVRO_DATA_FILE) {
      LOG.debug("Configuring for Avro export");
      configureGenericRecordExportInputFormat(job, tableName);
    } else if (fileType == FileType.PARQUET_FILE) {
      LOG.debug("Configuring for Parquet export");
      configureGenericRecordExportInputFormat(job, tableName);
      String uri = "dataset:" + FileSystemUtil.makeQualified(getInputPath(), job.getConfiguration());
      DatasetKeyInputFormat.configure(job).readFrom(uri);
    }
  }

  private void configureGenericRecordExportInputFormat(Job job, String tableName)
      throws IOException {
    ConnManager connManager = context.getConnManager();
    Map<String, Integer> columnTypeInts;
    if (options.getCall() == null) {
      columnTypeInts = connManager.getColumnTypes(
          tableName,
          options.getSqlQuery());
    } else {
      columnTypeInts = connManager.getColumnTypesForProcedure(
          options.getCall());
    }
    String[] specifiedColumns = options.getColumns();
    MapWritable columnTypes = new MapWritable();
    for (Map.Entry<String, Integer> e : columnTypeInts.entrySet()) {
      String column = e.getKey();
      column = (specifiedColumns == null) ? column : options.getColumnNameCaseInsensitive(column);
      if (column != null) {
        Text columnName = new Text(column);
        Text columnType = new Text(connManager.toJavaType(tableName, column, e.getValue()));
        columnTypes.put(columnName, columnType);
      }
    }
    DefaultStringifier.store(job.getConfiguration(), columnTypes,
        AvroExportMapper.AVRO_COLUMN_TYPES_MAP);
  }

  @Override
  protected Class<? extends InputFormat> getInputFormatClass()
      throws ClassNotFoundException {
    if (isHCatJob) {
      return SqoopHCatUtilities.getInputFormatClass();
    }
    switch (fileType) {
      case AVRO_DATA_FILE:
        return AvroInputFormat.class;
      case PARQUET_FILE:
        return DatasetKeyInputFormat.class;
      default:
        return super.getInputFormatClass();
    }
  }

  @Override
  protected Class<? extends Mapper> getMapperClass() {
    if (isHCatJob) {
      return SqoopHCatUtilities.getExportMapperClass();
    }
    switch (fileType) {
      case SEQUENCE_FILE:
        return SequenceFileExportMapper.class;
      case AVRO_DATA_FILE:
        return AvroExportMapper.class;
      case PARQUET_FILE:
        return ParquetExportMapper.class;
      case UNKNOWN:
      default:
        return TextExportMapper.class;
    }
  }

  @Override
  protected void configureOutputFormat(Job job, String tableName,
      String tableClassName) throws IOException {

    ConnManager mgr = context.getConnManager();
    try {
      String username = options.getUsername();
      if (null == username || username.length() == 0) {
        DBConfiguration.configureDB(job.getConfiguration(),
            mgr.getDriverClass(),
            options.getConnectString(),
            options.getConnectionParams());
      } else {
        DBConfiguration.configureDB(job.getConfiguration(),
            mgr.getDriverClass(),
            options.getConnectString(),
            username, options.getPassword(),
            options.getConnectionParams());
      }

      String [] colNames = options.getColumns();
      if (null == colNames) {
        colNames = mgr.getColumnNames(tableName);
      }

      if (mgr.escapeTableNameOnExport()) {
        DBOutputFormat.setOutput(job, mgr.escapeTableName(tableName), mgr.escapeColNames(colNames));
      } else {
        DBOutputFormat.setOutput(job, tableName, mgr.escapeColNames(colNames));
      }

      job.setOutputFormatClass(getOutputFormatClass());
      job.getConfiguration().set(SQOOP_EXPORT_TABLE_CLASS_KEY, tableClassName);
    } catch (ClassNotFoundException cnfe) {
      throw new IOException("Could not load OutputFormat", cnfe);
    }
  }

}