class HashMap
  def initialize
    @prizes = [35, 25, 20, 15, 5]
    @participations = [
      Participation.new(10),
      Participation.new(10),
      Participation.new(10),
      Participation.new(6),
      Participation.new(4),
      Participation.new(4)
    ]
    @percent = 10
  end

  def mapping
    # try participations into groups directly without this first array of hashes and then create that...
    raw_distribution = @participations.map.with_index do |current, i|
      prize = @prizes[i] ? @prizes[i] * @percent : 0
      prize_percent = @prizes[i] ? @prizes[i] : 0
      { position: i+1, participation: current, percentage: prize_percent, prize: prize } 
    end
    puts '========> before <=========='
    puts raw_distribution
    groups = raw_distribution.group_by {|pos| pos[:participation].score }
    distribution = []
    groups.each do |group|
      recalculated_percentage = 0
      group.last.map{ |part| recalculated_percentage += part[:percentage]}
      recalculated_percentage = recalculated_percentage.to_f / group.last.count
      group.last.map do |part|
        part[:percentage] = recalculated_percentage
        part[:prize] = recalculated_percentage * @percent
        distribution << part
      end
    end
    puts '========> after <=========='
    puts distribution
  end
end


class Participation
  attr_accessor :score
  
  def initialize score
    @score = score
  end
end


h = HashMap.new
h.mapping