gistfile1.rb

# frozen_string_literal: true

require 'gruff'

def calc_score(start_day, stop = 1000)
  score = []
  card = 0

  0.step(1000, 20) do |day|
    card += 6 if start_day < day && day < stop
    score << (score.last || 0) + (1000 - day) * card * 200
  end

  score
end

g = Gruff::Line.new
g.labels = {}

0.step(1000, 20).to_a.each_with_index do |n, i|
  g.labels[i] = n
end

g.data('0 > 1000', calc_score(0, 1000))
g.data('0 > 500', calc_score(0, 500))
g.data('200 > 500', calc_score(200, 500))
g.data('200 > 1000', calc_score(200, 1000))
g.data('300 > 1000', calc_score(300, 1000))
g.data('500 > 1000', calc_score(500, 1000))

g.write('bar.png')