Play 2.0 Reactive File Upload using CSVReader and Iteratee. Parse a CSV file using Iteratee and send each line to a local elasticsearch instance

ReactiveFileUpload.scala

package controllers

import play.api.mvc._
import play.api.libs.iteratee.{Iteratee, Input}
import play.api.libs.concurrent.Promise
import play.api.libs.iteratee.Input.{El, EOF, Empty}
import au.com.bytecode.opencsv.CSVReader
import java.io.StringReader
import scala.collection.JavaConversions._
import play.api.libs.json.Json._
import play.api.libs.ws.WS

object ReactiveFileUpload extends Controller {
  def upload = Action(BodyParser(rh => new CsvIteratee(isFirst = true))) {
    request =>
      Ok("File Processed")
  }
}

case class CsvIteratee(state: Symbol = 'Cont, input: Input[Array[Byte]] = Empty, lastChunk: String = "", isFirst: Boolean = false) extends Iteratee[Array[Byte], Either[Result, String]] {
  def fold[B](
               done: (Either[Result, String], Input[Array[Byte]]) => Promise[B],
               cont: (Input[Array[Byte]] => Iteratee[Array[Byte], Either[Result, String]]) => Promise[B],
               error: (String, Input[Array[Byte]]) => Promise[B]
               ): Promise[B] = state match {
    case 'Done =>
      done(Right(lastChunk), Input.Empty)

    case 'Cont => cont(in => in match {
      case in: El[Array[Byte]] => {
        // Retrieve the part that has not been processed in the previous chunk and copy it in front of the current chunk
        val content = lastChunk + new String(in.e)
        val csvBody =
          if (isFirst)
            // Skip http header if it is the first chunk
            content.drop(content.indexOf("\r\n\r\n") + 4)
          else content
        val csv = new CSVReader(new StringReader(csvBody), ';')
        val lines = csv.readAll
        // Process all lines excepted the last one since it is cut by the chunk
        for (line <- lines.init)
          processLine(line)
        // Put forward the part that has not been processed
        val last = lines.last.toList.mkString(";")
        copy(input = in, lastChunk = last, isFirst = false)
      }
      case Empty => copy(input = in, isFirst = false)
      case EOF => copy(state = 'Done, input = in, isFirst = false)
      case _ => copy(state = 'Error, input = in, isFirst = false)
    })

    case _ =>
      error("Unexpected state", input)

  }

  def processLine(line: Array[String]) = WS.url("http://localhost:9200/affa/na/").post(
    toJson(
      Map(
        "date" -> toJson(line(0)),
        "trig" -> toJson(line(1)),
        "code" -> toJson(line(2)),
        "nbjours" -> toJson(line(3).toDouble)
      )
    )
  )
}

above code does not compile ,as extending Iteratee needs to override fold[B](folder: %28Step[Array[Byte], Either[Result, String]]%29 => Future[B]): Future[B].can you please help