/*
 * 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.spark.examples.pythonconverters

import scala.collection.JavaConversions._

import org.apache.spark.api.python.Converter
import org.apache.hadoop.hbase.client.{Put, Result}
import org.apache.hadoop.hbase.io.ImmutableBytesWritable
import org.apache.hadoop.hbase.util.Bytes
import org.apache.hadoop.hbase.KeyValue.Type
import org.apache.hadoop.hbase.CellUtil

/**
 * Implementation of [[org.apache.spark.api.python.Converter]] that converts an
 * HBase Result to a String
 */
class HBaseResultToStringConverter extends Converter[Any, String] {
  override def convert(obj: Any): String = {
    val result = obj.asInstanceOf[Result]
    Bytes.toStringBinary(result.value())
  }
}

/** 
 * JF: convert a Result object into a string with column family and qualifier names. Sth like 
 * 'columnfamily1:columnqualifier1:value1;columnfamily2:columnqualifier2:value2' etc. 
 * k-v pairs are separated by ';'. different columns for each cell is separated by ':'. 
 * Notice that we don't need the row key here, because it has been converted by 
 * ImmutableBytesWritableToStringConverter. 
 * 
 * http://apache-spark-user-list.1001560.n3.nabble.com/ \
 * pyspark-get-column-family-and-qualifier-names-from-hbase-table-td18613.html
 */ 
class CustomHBaseResultToStringConverter extends Converter[Any, String] { 
  override def convert(obj: Any): String = { 
    val result = obj.asInstanceOf[Result] 

    result.rawCells().map(cell => List(Bytes.toString(CellUtil.cloneFamily(cell)), 
      Bytes.toString(CellUtil.cloneQualifier(cell)), 
      Bytes.toString(CellUtil.cloneValue(cell))).mkString(":")).mkString(";") 
  } 
} 
class CustomHBaseResultToStringConverter1 extends Converter[Any, String]{
  override def convert(obj: Any): String = {
    import collection.JavaConverters._

    val result = obj.asInstanceOf[Result]
    val output = result.listCells.asScala.map(cell =>
        "{'cf':'%s','qf':'%s','value':'%s'}".format(
          Bytes.toStringBinary(CellUtil.cloneFamily(cell)),
          Bytes.toStringBinary(CellUtil.cloneQualifier(cell)),
          Bytes.toStringBinary(CellUtil.cloneValue(cell))
        ))
    // output is an instance of [[Buffer[String]]]
    output.mkString("\t")
  }
}

/**
 * Implementation of [[org.apache.spark.api.python.Converter]] that converts all 
 * the records in an HBase Result to a String. In the String, it contains row, column,
 * timesstamp, type and value
 * 
 * https://github.com/GenTang/spark_hbase
 */

class CustomHBaseResultToStringConverter2 extends Converter[Any, String]{
  override def convert(obj: Any): String = {
    import collection.JavaConverters._

    val result = obj.asInstanceOf[Result]
    val output = result.listCells.asScala.map(cell =>
        "{'columnFamliy':'%s','qualifier':'%s','timestamp':'%s','type':'%s','value':'%s'}".format(
          Bytes.toStringBinary(CellUtil.cloneFamily(cell)),
          Bytes.toStringBinary(CellUtil.cloneQualifier(cell)),
          cell.getTimestamp.toString,
          Type.codeToType(cell.getTypeByte),
          Bytes.toStringBinary(CellUtil.cloneValue(cell))
        ))
    // output is an instance of [[Buffer[String]]]
    output.mkString(" ")
  }
}


/**
 * Implementation of [[org.apache.spark.api.python.Converter]] that converts an
 * ImmutableBytesWritable to a String
 */
class ImmutableBytesWritableToStringConverter extends Converter[Any, String] {
  override def convert(obj: Any): String = {
    val key = obj.asInstanceOf[ImmutableBytesWritable]
    Bytes.toStringBinary(key.get())
  }
}

/**
 * Implementation of [[org.apache.spark.api.python.Converter]] that converts a
 * String to an ImmutableBytesWritable
 */
class StringToImmutableBytesWritableConverter extends Converter[Any, ImmutableBytesWritable] {
  override def convert(obj: Any): ImmutableBytesWritable = {
    val bytes = Bytes.toBytes(obj.asInstanceOf[String])
    new ImmutableBytesWritable(bytes)
  }
}

/**
 * Implementation of [[org.apache.spark.api.python.Converter]] that converts a
 * list of Strings to HBase Put
 */
class StringListToPutConverter extends Converter[Any, Put] {
  override def convert(obj: Any): Put = {
    val output = obj.asInstanceOf[java.util.ArrayList[String]].map(Bytes.toBytes(_)).toArray
    val put = new Put(output(0))
    put.add(output(1), output(2), output(3))
  }
}