# frozen_string_literal: true

require "bls"
require_relative "kzg/version"

# KZG Commitment library.
module KZG
  class Error < StandardError
  end

  autoload :Setting, "kzg/setting"
  autoload :Polynomial, "kzg/polynomial"
  autoload :Commitment, "kzg/commitment"

  module_function

  # Setup elements of elliptic curve from +secret+.
  # Note: Since the random secret must not be known to anyone,
  # this Trusted Setup usually needs to be performed using an MPC or similar.
  # @param [Integer] secret random secret.
  # @param [Integer] n number of parameters.
  # @return [KZG::Setting]
  def setup_params(secret, n)
    s1 = Array.new(n)
    s2 = Array.new(n)
    s = BLS::Fr.new(secret)
    s_pow = BLS::Fr::ONE
    n.times do |i|
      s1[i] = BLS::PointG1::BASE * s_pow
      s2[i] = BLS::PointG2::BASE * s_pow
      tmp = s_pow
      s_pow = tmp * s
    end
    Setting.new(s1, s2)
  end
end