def self.missing_attachments_styles
current_styles = current_attachments_styles
registered_styles = get_registered_attachments_styles
Hash.new.tap do |missing_styles|
current_styles.each do |klass, attachment_definitions|
attachment_definitions.each do |attachment_name, styles|
registered = registered_styles[klass][attachment_name] || [] rescue []
missed = styles - registered
if missed.present?
klass_sym = klass.to_s.to_sym
missing_styles[klass_sym] ||= Hash.new
missing_styles[klass_sym][attachment_name.to_sym] ||= Array.new
missing_styles[klass_sym][attachment_name.to_sym].concat(missed.to_a)
missing_styles[klass_sym][attachment_name.to_sym].map!(&:to_s).sort!.map!(&:to_sym).uniq!
end
end
end
end
end