class MultiMeasure

# File lib/multi_measure.rb, line 32
def config
  @config ||= default_config
end

# File lib/multi_measure.rb, line 13
def configure
  yield config
  @config = config
end

# File lib/multi_measure.rb, line 54
def current_measurements
  instance.current_measurements
end

# File lib/multi_measure.rb, line 18
def default_config
  MultiMeasure::Config.build_from(
    output_prefix: "MULTI_MEASURE_TOTAL",
    write_to: STDOUT,
    middleware: {
      env_var: "MULTI_MEASURE_ENABLED"
    }
  )
end

# File lib/multi_measure.rb, line 44
def done
  instance.print_all_measurements
  reset
end

# File lib/multi_measure.rb, line 58
def measure(*names, &block)
  instance.measure(*names, &block)
end

# File lib/multi_measure.rb, line 71
def initialize
  @measurements = ThreadSafeHash.new
end

# File lib/multi_measure.rb, line 40
def reset
  Thread.current[STORE_KEY] = nil
end

# File lib/multi_measure.rb, line 28
def set_default_config
  @config = default_config
end

# File lib/multi_measure.rb, line 36
def start
  Thread.current[STORE_KEY] = new
end

# File lib/multi_measure.rb, line 49
def track_measurements
  start
  yield.tap { done }
end

# File lib/multi_measure.rb, line 66
def instance
  Thread.current.fetch(STORE_KEY) { NullMeasurer.new }
end

# File lib/multi_measure.rb, line 94
def current_measurements
  measurements.to_normal_hash
end

# File lib/multi_measure.rb, line 75
def measure(*names)
  return_value = nil

  state = MeasurementState.new

  time = Benchmark.realtime do
    return_value = yield state
  end

  if state.track_measurement?
    names.each do |name|
      measurements[name] ||= []
      measurements[name] << time
    end
  end

  return_value
end

# File lib/multi_measure.rb, line 98
def print_all_measurements
  longest_key_length = 0
  measurements.each do |key, _value|
    if key.length > longest_key_length
      longest_key_length = key.length
    end
  end

  longest_time_length = 0
  measurements.each do |_key, times|
    length = to_ms(times.sum).to_s.length
    if length > longest_time_length
      longest_time_length = length
    end
  end

  sorted_measurements = measurements.sort_by { |_key, times| times.sum }
  sorted_measurements.each do |key, times|
    key = key.rjust(longest_key_length)
    time = to_ms(times.sum).to_s.rjust(longest_time_length)

    std = MathHelpers.standard_deviation(times.map { |t| to_ms(t) }).round(2)
    extra_info = "(+/- #{std}ms, #{times.size} calls)"

    write_to_io "#{key} #{time}ms #{extra_info}"
  end
end

# File lib/multi_measure.rb, line 140
def config
  self.class.config
end

# File lib/multi_measure.rb, line 144
def to_ms(seconds)
  (seconds * 1_000).round(1)
end

# File lib/multi_measure.rb, line 130
def write_to_io(message)
  message = "#{config.output_prefix} #{message}"

  if config.write_to.respond_to?(:debug)
    config.write_to.debug(message)
  else
    config.write_to.puts(message)
  end
end