module FFaker::Avatar

def check_passed_params(size, format, bgset)
  invalid_size_error unless size =~ /^[0-9]+x[0-9]+$/
  invalid_format_error unless SUPPORTED_FORMATS.include?(format)
  invalid_background_number unless bgset.nil? || (1..2).cover?(bgset.to_i)
end

def image(slug = nil, size = '300x300', format = 'png', bgset = nil)
  check_passed_params(size, format, bgset)
  slug ||= FFaker::Lorem.words.join
  "https://robohash.org/#{slug}.#{format}?size=#{size}#{'&bgset=bg' + bgset.to_s if bgset}"
end

def invalid_background_number
  raise ArgumentError, 'Not a supported background number. Choose eather 1 or 2'
end

def invalid_format_error
  raise ArgumentError, "Supported formats are #{SUPPORTED_FORMATS.join(', ')}"
end

def invalid_size_error
  raise ArgumentError, 'Size should be specified in format 300x300'
end