module DDMemoize

# File lib/ddmemoize.rb, line 20
def self.activate(mod)
  mod.extend(Mixin)
end

# File lib/ddmemoize.rb, line 25
def enable_metrics
  @metrics_enabled = true
end

# File lib/ddmemoize.rb, line 33
def metrics_counter
  @_metrics_counter ||= DDMetrics::Counter.new
end

# File lib/ddmemoize.rb, line 29
def metrics_enabled?
  @metrics_enabled
end

# File lib/ddmemoize.rb, line 38
def self.print_metrics
  headers = %w[memoization hit miss %]

  rows_raw = DDMemoize.metrics_counter.map do |label, count|
    {
      name: label.fetch(:method),
      type: label.fetch(:type),
      count: count,
    }
  end

  rows = rows_raw.group_by { |r| r[:name] }.map do |name, rows_for_name|
    rows_by_type = rows_for_name.group_by { |r| r[:type] }

    num_hit = rows_by_type.fetch(:hit, []).fetch(0, {}).fetch(:count, 0)
    num_miss = rows_by_type.fetch(:miss, []).fetch(0, {}).fetch(:count, 0)
    pct = num_hit.to_f / (num_hit + num_miss).to_f

    [name, num_hit.to_s, num_miss.to_s, "#{format('%3.1f', pct * 100)}%"]
  end

  all_rows = [headers] + rows
  puts DDMetrics::Table.new(all_rows).to_s
end