# frozen_string_literal: true

# Uniquify
#
# Return a version of the given 'base' string that is unique
# by appending a counter to it. Uniqueness is determined by
# repeated calls to the passed block.
#
# You can pass an initial value for the counter, if not given
# counting starts from 1.
#
# If `base` is a function/proc, we expect that calling it with a
# candidate counter returns a string to test/return.

module Gitlab
  module Utils
    class Uniquify
      def initialize(counter = nil)
        @counter = counter
      end

      def string(base)
        @base = base

        increment_counter! while yield(base_string)
        base_string
      end

      private

      def base_string
        if @base.respond_to?(:call)
          @base.call(@counter)
        else
          "#{@base}#{@counter}"
        end
      end

      def increment_counter!
        @counter ||= 0
        @counter += 1
      end
    end
  end
end