class Airbrake::PerformanceNotifier

def add_filter(filter = nil, &block)
  @filter_chain.add_filter(block_given? ? block : filter)
end

def check_configuration: (Airbrake::Query metric) -> Airbrake::Promise

def check_configuration(metric)
  promise = @config.check_configuration
  return promise if promise.rejected?
  promise = @config.check_performance_options(metric)
  return promise if promise.rejected?
  if metric.timing && metric.timing == 0
    return Promise.new.reject(':timing cannot be zero')
  end
  Promise.new
end

def close
  @payload.synchronize do
    @schedule_flush.kill if @schedule_flush
    @sync_sender.close
    @async_sender.close
  end
end

def delete_filter(filter_class)
  @filter_chain.delete_filter(filter_class)
end

def initialize
  @config = Airbrake::Config.instance
  @flush_period = Airbrake::Config.instance.performance_stats_flush_period
  @async_sender = AsyncSender.new(:put, self.class.name)
  @sync_sender = SyncSender.new(:put)
  @schedule_flush = nil
  @filter_chain = FilterChain.new
  @payload = {}.extend(MonitorMixin)
  @has_payload = @payload.new_cond
end

def notify: (Airbrake::Query metric) -> untyped

def notify(metric)
  @payload.synchronize do
    send_metric(metric, sync: false)
  end
end

def notify_sync(metric)
  send_metric(metric, sync: true).value
end

def schedule_flush
  @schedule_flush ||= Thread.new do
    loop do
      @payload.synchronize do
        @last_flush_time ||= MonotonicTime.time_in_s
        while (MonotonicTime.time_in_s - @last_flush_time) < @flush_period
          @has_payload.wait(@flush_period)
        end
        if @payload.none?
          @last_flush_time = nil
          next
        end
        send(@async_sender, @payload, Airbrake::Promise.new)
        @payload.clear
      end
    end
  end
end

def send(sender, payload, promise)
  raise "payload cannot be empty. Race?" if payload.none?
  with_grouped_payload(payload) do |metric_hash, destination|
    url = URI.join(
      @config.apm_host,
      "api/v5/projects/#{@config.project_id}/#{destination}",
    )
    logger.debug do
      "#{LOG_LABEL} #{self.class.name}##{__method__}: #{metric_hash}"
    end
    sender.send(metric_hash, promise, url)
  end
  promise
end

def send_metric: ((Airbrake::Query | Airbrake::Request) metric, sync: false) -> Airbrake::Promise

def send_metric(metric, sync:)
  promise = check_configuration(metric)
  return promise if promise.rejected?
  @filter_chain.refine(metric)
  if metric.ignored?
    return Promise.new.reject("#{metric.class} was ignored by a filter")
  end
  update_payload(metric)
  if sync || @flush_period == 0
    send(@sync_sender, @payload, promise)
  else
    @has_payload.signal
    schedule_flush
  end
end

def serialize_metrics(metrics)
  metrics.map do |metric, stats|
    metric_hash = metric.to_h.merge!(stats[:total].to_h)
    if metric.groups.any?
      group_stats = stats.reject { |name, _stat| name == :total }
      metric_hash['groups'] = group_stats.merge(group_stats) do |_name, stat|
        stat.to_h
      end
    end
    metric_hash
  end
end

def update_payload(metric)
  if (total_stat = @payload[metric])
    @payload.key(total_stat).merge(metric)
  else
    @payload[metric] = { total: Airbrake::Stat.new }
  end
  @payload[metric][:total].increment_ms(metric.timing)
  metric.groups.each do |name, ms|
    @payload[metric][name] ||= Airbrake::Stat.new
    @payload[metric][name].increment_ms(ms)
  end
end

def with_grouped_payload(raw_payload)
  grouped_payload = raw_payload.group_by do |metric, _stats|
    [metric.cargo, metric.destination]
  end
  grouped_payload.each do |(cargo, destination), metrics|
    payload = {}
    payload[cargo] = serialize_metrics(metrics)
    payload['environment'] = @config.environment if @config.environment
    yield(payload, destination)
  end
end