require 'pry'

class Triplet
  attr_reader :a, :b, :c

  def initialize(a, b, c)
    @a = a
    @b = b
    @c = c
  end

  def self.where(args)
    if min_and_max_factors_given?(args)
      get_tripets(args[:max_factor], min_factor: args[:min_factor])
    elsif max_factor_and_sum_given?(args)
      get_tripets(args[:max_factor], sum: args[:sum])
    elsif max_factor_given?(args)
      get_tripets(args[:max_factor])
    end
  end

  def sum
    a + b + c
  end

  def product
    a * b * c
  end

  def pythagorean?
    a**2 + b**2 == c**2
  end

  private

  def self.max_factor_given?(args)
    args.has_key?(:max_factor)
  end

  def self.min_and_max_factors_given?(args)
    args.has_key?(:min_factor) && args.has_key?(:max_factor)
  end

  def self.max_factor_and_sum_given?(args)
    args.has_key?(:max_factor) && args.has_key?(:sum)
  end

  def self.get_tripets(c_high, options = {})
    triplets = []
    options[:min_factor] == nil ? c_low = 3 : c_low = options[:min_factor] + 2
    c_high.downto(c_low) do |c|
      b = c - 1
      while b**2 > c**2 / 2 do
        a = Math.sqrt(c**2 - b**2).to_i
        if options[:min_factor] != nil
          if Triplet.new(a, b, c).pythagorean? && a >= options[:min_factor]
            triplets << Triplet.new(a, b, c)
            break
          end
        elsif options[:sum] != nil
          if Triplet.new(a, b, c).pythagorean? && Triplet.new(a, b, c).sum == options[:sum]
            triplets << Triplet.new(a, b, c)
            break
          end
        else
          if Triplet.new(a, b, c).pythagorean?
            triplets << Triplet.new(a, b, c)
            break
          end
        end
        b -= 1
      end
      b = c - 1
    end
    triplets
  end
end