private def updateList()

in app/story_packages/model/frontsapi.scala [82:109]
23 lines of code
3 McCabe index (conditional complexity)

  private def updateList(update: UpdateList, identity: User, blocks: List[Trail]): List[Trail] = {
    val trail: Trail = blocks
      .find(_.id == update.item)
      .map { currentTrail =>
        val newMeta = for (updateMeta <- update.itemMeta) yield updateMeta
        currentTrail.copy(meta = newMeta)
      }
      .getOrElse(Trail(update.item, DateTime.now.getMillis, Some(getUserName(identity)), update.itemMeta))

    val listWithoutItem = blocks.filterNot(_.id == update.item)

    val splitList: (List[Trail], List[Trail]) = {
      //Different index logic if item is being place at itself in list
      //(Eg for metadata update, or group change, index must come from list without item removed)
      if (update.position.exists(_ == update.item)) {
        val index = blocks.indexWhere(_.id == update.item)
        listWithoutItem.splitAt(index)
      }
      else {
        val index = update.after.filter {_ == true}
          .map {_ => listWithoutItem.indexWhere(t => update.position.exists(_ == t.id)) + 1}
          .getOrElse { listWithoutItem.indexWhere(t => update.position.exists(_ == t.id)) }
        listWithoutItem.splitAt(index)
      }
    }

    splitList._1 ::: (trail +: splitList._2)
  }