package sandcrawler

import scala.math
import scala.util.parsing.json.JSON
import scala.util.parsing.json.JSONArray
import scala.util.parsing.json.JSONObject

import cascading.flow.FlowDef
import cascading.tuple.Fields
import com.twitter.scalding._
import com.twitter.scalding.typed.TDsl._
import parallelai.spyglass.hbase.HBasePipeConversions

class CrossrefScorable extends Scorable with HBasePipeConversions {
  // TODO: Generalize args so there can be multiple Crossref pipes in one job.
  def getSource(args : Args) : Source = {
    TextLine(args("crossref-input"))
  }

  def getFeaturesPipe(args : Args)(implicit mode : Mode, flowDef : FlowDef) : TypedPipe[Option[MapFeatures]] = {
    getSource(args).read
      .toTypedPipe[String](new Fields("line"))
      .filter { CrossrefScorable.keepRecord(_) }
      .map { CrossrefScorable.jsonToMapFeatures(_) }
  }
}

object CrossrefScorable {

  val ContentTypeWhitelist: Set[String] = Set(
    "book",
    "book-chapter",
    "dataset",
    "dissertation",
    "journal-article",
    "letter",
    "monograph",
    "posted-content",
    "pre-print",
    "proceedings-article",
    "report",
    "working-paper")

  def keepRecord(json : String) : Boolean = {
    Scorable.jsonToMap(json) match {
      case None => false
      case Some(map) => {
        mapToTitle(map) match {
          case None => false
          case Some(title) => title.length <= Scorable.MaxTitleLength
        }
      }
    }
  }

  // Returns None if title is null, empty, or too long.
  def mapToTitle(map : Map[String, Any]) : Option[String] = {
    def getTitle : Option[String] = {
      if (map contains "title") {
        val titles = map("title").asInstanceOf[List[String]]
        if (titles.isEmpty || titles == null) None else Some(titles(0))
      } else {
        None
      }
    }

    def getSubtitle : Option[String] = {
      if (map contains "subtitle") {
        val subtitles = map("subtitle").asInstanceOf[List[String]]
        if (subtitles.isEmpty || subtitles == null) {
          None
        } else {
          val sub = subtitles(0)
          if (sub == null || sub.isEmpty) {
            None
          } else {
            Some(sub)
          }
        }
      } else {
        None
      }
    }

    getTitle match {
      case None => None
      case Some(baseTitle) => {
        if (baseTitle == null) {
          None
        } else {
          getSubtitle match {
            case None => Some(baseTitle)
            case Some(baseSubtitle) => Some(baseTitle.concat(":".concat(baseSubtitle)))
          }
        }
      }
    }
  }

  def mapToAuthorList(map : Map[String, Any]) : List[String] = {
    if (map contains "author") {
      val objArray = map("author").asInstanceOf[List[Any]].map(e => e.asInstanceOf[Map[String,Any]])
      // TODO(bnewbold): combine given and family names?
      objArray
        .filter(e => e contains "family")
        .map(e => e.get("family").get.asInstanceOf[String])
    } else {
      List()
    }
  }

  def mapToYear(map : Map[String, Any]) : Option[Int] = {
    map.get("created") match {
      case None => None
      case Some(created) => {
        Some(created.asInstanceOf[Map[String,Any]]
          .get("date-parts")
          .get
          .asInstanceOf[List[Any]](0)
          .asInstanceOf[List[Any]](0)
          .asInstanceOf[Double]
          .toInt)
      }
    }
  }

  def jsonToMapFeatures(json : String) : Option[MapFeatures] = {
    def makeMapFeatures(title : String, doi : String, authors : List[String], year : Int, contentType : String) : Option[MapFeatures] = {
      if (doi.isEmpty || doi == null || authors.length == 0 || !(ContentTypeWhitelist contains contentType)) {
        None
      } else {
        val sf : ScorableFeatures = ScorableFeatures.create(title=title, authors=authors, doi=doi.toLowerCase(), year=year)
        sf.toSlug match {
          case None => None
          case Some(slug) => Some(MapFeatures(slug, sf.toString))
        }
      }
    }
    Scorable.jsonToMap(json) match {
      case None => None
      case Some(map) =>
        mapToTitle(map) match {
          case None => None
          case Some(title) => makeMapFeatures(
            title=title,
            doi=Scorable.getString(map, "DOI"),
            authors=mapToAuthorList(map),
            year=mapToYear(map).getOrElse(0),
            contentType=map.get("type").map(e => e.asInstanceOf[String]).getOrElse("MISSING-CONTENT-TYPE"))
        }
    }
  }
}