lila/modules/socket/src/main/UserLagCache.scala

package lila.socket

import chess.Centis
import com.github.blemale.scaffeine.Cache
import scala.concurrent.duration._

object UserLagCache {

  private val cache: Cache[String, Centis] = lila.memo.CacheApi.scaffeineNoScheduler
    .expireAfterWrite(15 minutes)
    .build[String, Centis]()

  def put(userId: String, lag: Centis): Unit =
    if (lag.centis >= 0)
      cache.put(
        userId,
        cache.getIfPresent(userId).fold(lag) {
          _ avg lag
        }
      )

  def get(userId: String): Option[Centis] = cache.getIfPresent(userId)

  def getLagRating(userId: String): Option[Int] =
    get(userId) map {
      case i if i <= Centis(15) => 4
      case i if i <= Centis(30) => 3
      case i if i <= Centis(50) => 2
      case _                    => 1
    }
}