class IngredientManagement
  attr_reader :ranges, :ids
  def initialize(ranges, ids)
    @ranges = ranges
    @ids = ids
  end

  def self.for(input)
    ranges, ids = input.split("\n\n")
    new(
      ranges.split("\n").map{ |r| s, e = r.split("-").map(&:to_i); s..e },
      ids.split("\n").map(&:to_i)
    )
  end

  def fresh?(id)
    ranges.any? { |range| range.include? id }
  end

  def fresh_ingredient_ids
    ids.select { |id| fresh? id }
  end

  def all_fresh_ids
    # this makes it OOM!
    # return ranges.map(&:to_a).flatten.uniq
    []
  end

  def all_fresh_ids_count
    combine_ranges.map(&:size).sum
  end

  def combine_two_ranges(r1, r2)
    return [r1, r2] if r2.begin > r1.end || r1.begin > r2.end

    [([r1.begin, r2.begin].min)..([r1.end, r2.end].max)]
  end

  def combine_ranges(rs = ranges)
    rs.sort_by!(&:begin)
    index = 0
    while index < rs.length - 1
      c2r = combine_two_ranges(rs[index], rs[index + 1])
      if c2r.length == 2 # did not combine
        index += 1
      else # combined
        rs.delete_at(index)
        rs.delete_at(index)
        rs.insert(index, c2r[0])
      end
    end

    rs
  end
end