package eu.dnetlib.dhp.sx.graph

import eu.dnetlib.dhp.application.ArgumentApplicationParser
import eu.dnetlib.dhp.schema.oaf.{Relation, Result}
import org.apache.commons.io.IOUtils
import org.apache.spark.SparkConf
import org.apache.spark.sql._
import org.slf4j.{Logger, LoggerFactory}

import scala.collection.JavaConverters._
object SparkResolveRelation {
  def main(args: Array[String]): Unit = {
    val log: Logger = LoggerFactory.getLogger(getClass)
    val conf: SparkConf = new SparkConf()
    val parser = new ArgumentApplicationParser(IOUtils.toString(getClass.getResourceAsStream("/eu/dnetlib/dhp/sx/graph/resolve_relations_params.json")))
    parser.parseArgument(args)
    val spark: SparkSession =
      SparkSession
        .builder()
        .config(conf)
        .appName(getClass.getSimpleName)
        .master(parser.get("master")).getOrCreate()


    val relationPath = parser.get("relationPath")
    log.info(s"sourcePath  -> $relationPath")
    val entityPath = parser.get("entityPath")
    log.info(s"targetPath  -> $entityPath")
    val workingPath = parser.get("workingPath")
    log.info(s"workingPath  -> $workingPath")


    implicit  val oafEncoder: Encoder[Result] = Encoders.kryo(classOf[Result])
    implicit  val relEncoder: Encoder[Relation] = Encoders.kryo(classOf[Relation])
    import spark.implicits._
    val entities:Dataset[Result] = spark.read.load(s"$entityPath/*").as[Result]

    entities.flatMap(e => e.getPid.asScala
      .map(p =>
             convertPidToDNETIdentifier(p.getValue, p.getQualifier.getClassid))
            .filter(s => s!= null)
            .map(s => (s,e.getId))
    ).groupByKey(_._1)
      .reduceGroups((x,y) => if (x._2.startsWith("50|doi") || x._2.startsWith("50|pmid")) x else y)
      .map(s =>s._2)
      .write
      .mode(SaveMode.Overwrite)
      .save(s"$workingPath/resolvedPid")

    val rPid:Dataset[(String,String)] = spark.read.load(s"$workingPath/resolvedPid").as[(String,String)]

    val relationDs:Dataset[(String,Relation)] = spark.read.load(relationPath).as[Relation].map(r => (r.getSource.toLowerCase, r))(Encoders.tuple(Encoders.STRING, relEncoder))

    relationDs.joinWith(rPid, relationDs("_1").equalTo(rPid("_1")), "left").map{
      m =>
        val sourceResolved = m._2
        val currentRelation = m._1._2
        if (sourceResolved!=null && sourceResolved._2.nonEmpty)
          currentRelation.setSource(sourceResolved._2)
        currentRelation
    }.write
      .mode(SaveMode.Overwrite)
      .save(s"$workingPath/resolvedSource")


    val relationSourceResolved:Dataset[(String,Relation)] = spark.read.load(s"$workingPath/resolvedSource").as[Relation].map(r => (r.getTarget.toLowerCase, r))(Encoders.tuple(Encoders.STRING, relEncoder))
    relationSourceResolved.joinWith(rPid, relationSourceResolved("_1").equalTo(rPid("_1")), "left").map{
      m =>
        val targetResolved = m._2
        val currentRelation = m._1._2
        if (targetResolved!=null && targetResolved._2.nonEmpty)
          currentRelation.setTarget(targetResolved._2)
        currentRelation
    }.filter(r => r.getSource.startsWith("50")&& r.getTarget.startsWith("50"))
      .write
      .mode(SaveMode.Overwrite)
      .save(s"$workingPath/resolvedRelation")
  }




  def convertPidToDNETIdentifier(pid:String, pidType: String):String = {
    if (pid==null || pid.isEmpty || pidType== null || pidType.isEmpty)
      null
    else
      s"unresolved::${pid.toLowerCase}::${pidType.toLowerCase}"
  }

}