class Array

# File lib/kujibiki/core_ext/array.rb, line 3
def sample(n=nil, random: nil, weight: nil)
  return call_original_sample(n, random: random) if (weight.nil? || self.size <= 1)

  unless weight.select {|w| w > 0}.size >= self.size
    raise ArgumentError, "weight size must be equal to array size(#{self.size})"
  end

  n = 1 unless n
  n = self.size if n > self.size

  begin
    sum = weight.inject(0.0, :+)
    normalized_hash = self.each_with_object({}).with_index do |(e, h), i|
      h[e] = weight[i] / sum
    end

    pick_max = 1.0
    sampled = n.times.map do
      pick = random ? random.rand(0..pick_max) : rand(0..pick_max)

      e, weight = normalized_hash.find do |e, weight|
        (pick <= weight) || ((pick -= weight) && false)
      end

      pick_max -= weight
      normalized_hash[e] = 0 and e
    end

    sampled.size > 1 ? sampled : sampled.first
  rescue => e
    warn([e.class, e.message, e.backtrace.join("\n")].join(' '))
    return call_original_sample(n, random: random)
  end
end

# File lib/kujibiki/core_ext/array.rb, line 40
def call_original_sample(n=nil, random: nil)
  if n
    if random
      _sample(n, random: random)
    else
      _sample(n)
    end
  else
    if random
      _sample(random: random)
    else
      _sample
    end
  end
end