package com.twitter.recos.user_video_graph

import com.twitter.finagle.Service
import com.twitter.finagle.http.Request
import com.twitter.finagle.http.Response
import com.twitter.finagle.http.Status
import com.twitter.finagle.http.Version
import com.twitter.frigate.common.util.HTMLUtil
import com.twitter.graphjet.algorithms.TweetIDMask
import com.twitter.graphjet.bipartite.segment.BipartiteGraphSegment
import com.twitter.graphjet.bipartite.MultiSegmentIterator
import com.twitter.graphjet.bipartite.MultiSegmentPowerLawBipartiteGraph
import com.twitter.logging.Logger
import com.twitter.util.Future
import java.util.Random
import scala.collection.mutable.ListBuffer

class UserTweetGraphEdgeHttpHandler(graph: MultiSegmentPowerLawBipartiteGraph)
    extends Service[Request, Response] {
  private val log = Logger("UserTweetGraphEdgeHttpHandler")
  private val tweetIDMask = new TweetIDMask()

  def getCardInfo(rightNode: Long): String = {
    val bits: Long = rightNode & TweetIDMask.METAMASK
    bits match {
      case TweetIDMask.PHOTO => "Photo"
      case TweetIDMask.PLAYER => "Video"
      case TweetIDMask.SUMMARY => "Url"
      case TweetIDMask.PROMOTION => "Promotion"
      case _ => "Regular"
    }
  }

  private def getUserEdges(userId: Long): ListBuffer[Edge] = {
    val random = new Random()
    val iterator =
      graph
        .getRandomLeftNodeEdges(userId, 10, random).asInstanceOf[MultiSegmentIterator[
          BipartiteGraphSegment
        ]]
    val tweets = new ListBuffer[Edge]()
    if (iterator != null) {
      while (iterator.hasNext) {
        val rightNode = iterator.nextLong()
        val edgeType = iterator.currentEdgeType()
        tweets += Edge(
          tweetIDMask.restore(rightNode),
          UserVideoEdgeTypeMask(edgeType).toString,
          getCardInfo(rightNode),
        )
      }
    }
    tweets
  }

  def apply(httpRequest: Request): Future[Response] = {
    log.info("UserTweetGraphEdgeHttpHandler params: " + httpRequest.getParams())
    val time0 = System.currentTimeMillis

    val tweetId = httpRequest.getLongParam("tweetId")
    val queryTweetDegree = graph.getRightNodeDegree(tweetId)
    val tweetEdges = getTweetEdges(tweetId)

    val userId = httpRequest.getLongParam("userId")
    val queryUserDegree = graph.getLeftNodeDegree(userId)

    val response = Response(Version.Http11, Status.Ok)
    val userEdges = getUserEdges(userId)
    val elapsed = System.currentTimeMillis - time0
    val comment = ("Please specify \"userId\"  or \"tweetId\" param." +
      "\n query tweet degree = " + queryTweetDegree +
      "\n query user degree = " + queryUserDegree +
      "\n done in %d ms<br>").format(elapsed)
    val tweetContent = userEdges.toList
      .map { edge =>
        s"<b>TweetId</b>: ${edge.tweetId},\n<b>Action type</b>: ${edge.actionType},\n<b>Card type</b>: ${edge.cardType}"
          .replaceAll("\n", " ")
      }.mkString("\n<br>\n")

    response.setContentString(
      HTMLUtil.html.replace("XXXXX", comment + tweetContent + "\n<hr/>\n" + tweetEdges.toString()))
    Future.value(response)
  }

  private def getTweetEdges(tweetId: Long): ListBuffer[Long] = {
    val random = new Random()
    val iterator =
      graph
        .getRandomRightNodeEdges(tweetId, 500, random).asInstanceOf[MultiSegmentIterator[
          BipartiteGraphSegment
        ]]
    val terms = new ListBuffer[Long]()
    if (iterator != null) {
      while (iterator.hasNext) { terms += iterator.nextLong() }
    }
    terms.distinct
  }

}

case class Edge(tweetId: Long, actionType: String, cardType: String)