table_formatter.rb

class ReportFormatter
  class << self
    def ascii(data)
      new.ascii(data)
    end
  end

  # {first_table: [{title: "contents"}], second_table: []}
  def ascii(data)
    data.map do |k, v|
      @headings = headings(v)
      Terminal::Table.new title: title(k), headings: @headings, rows: v
    end
  end

  private

  def headings(rows)
    rows.map(&:keys).flatten.uniq.map { |h| title(h) }
  end

  def  title(label)
    label.to_s.gsub("_", " ").capitlize
  end

  def rows(data)
    data.reduce([]) { |a, e| a << e.values if e.keys == @headings }
  end
end