class SplitIoClient::Engine::Common::ImpressionCounter

def self.truncate_time_frame(timestamp_ms)
  timestamp_ms - (timestamp_ms % TIME_INTERVAL_MS)
end

def inc(split_name, time_frame)
  key = make_key(split_name, time_frame)
  current_amount = @cache[key]
  @cache[key] = current_amount.nil? ? DEFAULT_AMOUNT : (current_amount + DEFAULT_AMOUNT)
end

def initialize
  @cache = Concurrent::Hash.new
end

def make_key(split_name, time_frame)
  "#{split_name}::#{ImpressionCounter.truncate_time_frame(time_frame)}"
end

def pop_all
  to_return = Concurrent::Hash.new
  @cache.each do |key, value|
    to_return[key] = value
  end
  @cache.clear
  to_return
end