class Paperclip::Validators::AttachmentSizeValidator

def self.helper_method_name
  :validates_attachment_size
end

def check_validity!
  unless (AVAILABLE_CHECKS + [:in]).any? { |argument| options.has_key?(argument) }
    raise ArgumentError, "You must pass either :less_than, :greater_than, or :in to the validator"
  end
end

def extract_option_value(option, option_value)
  if option_value.is_a?(Range)
    if [:less_than, :less_than_or_equal_to].include?(option)
      option_value.max
    else
      option_value.min
    end
  else
    option_value
  end
end

def extract_options(options)
  if range = options[:in]
    if !options[:in].respond_to?(:call)
      options[:less_than_or_equal_to] = range.max
      options[:greater_than_or_equal_to] = range.min
    else
      options[:less_than_or_equal_to] = range
      options[:greater_than_or_equal_to] = range
    end
  end
end

def human_size(size)
  if defined?(ActiveSupport::NumberHelper) # Rails 4.0+
    ActiveSupport::NumberHelper.number_to_human_size(size)
  else
    storage_units_format = I18n.translate(:'number.human.storage_units.format', :locale => options[:locale], :raise => true)
    unit = I18n.translate(:'number.human.storage_units.units.byte', :locale => options[:locale], :count => size.to_i, :raise => true)
    storage_units_format.gsub(/%n/, size.to_i.to_s).gsub(/%u/, unit).html_safe
  end
end

def initialize(options)
  extract_options(options)
  super
end

def max_value_in_human_size(record)
  value = options[:less_than_or_equal_to] || options[:less_than]
  value = value.call(record) if value.respond_to?(:call)
  value = value.max if value.respond_to?(:max)
  human_size(value)
end

def min_value_in_human_size(record)
  value = options[:greater_than_or_equal_to] || options[:greater_than]
  value = value.call(record) if value.respond_to?(:call)
  value = value.min if value.respond_to?(:min)
  human_size(value)
end

def validate_each(record, attr_name, value)
  base_attr_name = attr_name
  attr_name = "#{attr_name}_file_size".to_sym
  value = record.send(:read_attribute_for_validation, attr_name)
  unless value.blank?
    options.slice(*AVAILABLE_CHECKS).each do |option, option_value|
      option_value = option_value.call(record) if option_value.is_a?(Proc)
      option_value = extract_option_value(option, option_value)
      unless value.send(CHECKS[option], option_value)
        error_message_key = options[:in] ? :in_between : option
        [ attr_name, base_attr_name ].each do |error_attr_name|
          record.errors.add(error_attr_name, error_message_key, filtered_options(value).merge(
            :min => min_value_in_human_size(record),
            :max => max_value_in_human_size(record),
            :count => human_size(option_value)
          ))
        end
      end
    end
  end
end