UnreadCounterFun.kt

  private fun getNumberOfAttachmentsInGroupConvesationsFun() {
    return getCount({conv -> conv.groupId != null}, {it -> it.type == MessageType.ATTACHMENT && it.unread})
  }

  private fun getUnreadCountFromUsersFun() {
    return getCount({conv -> conv.recipientId != null}, {message -> message.unread})
  }

  private fun getTotalNumberOfMessages() = getCount({true}, {true})

  private fun getCount(convFilter: (Conversation) -> Boolean, messageFilter: (Message) -> Boolean) {
    datasource.getConversations()
        .filter(convFilter)
        .flatMap { it.messages }
        .filter(messageFilter)
        .fold(0, { count, message -> count + 1})
  }