class ActiveStorage::VariantWithRecord

def create_or_find_record(image:)
  @record =
    ActiveRecord::Base.connected_to(role: ActiveRecord.writing_role) do
      blob.variant_records.create_or_find_by!(variation_digest: variation.digest) do |record|
        record.image.attach(image)
      end
    end
end

def image
  record&.image
end

def initialize(blob, variation)
  @blob, @variation = blob, ActiveStorage::Variation.wrap(variation)
end

def process
  transform_blob { |image| create_or_find_record(image: image) } unless processed?
end

def processed
  process
  self
end

def processed?
  record.present?
end

def record
  @record ||= if blob.variant_records.loaded?
    blob.variant_records.find { |v| v.variation_digest == variation.digest }
  else
    blob.variant_records.find_by(variation_digest: variation.digest)
  end
end

def transform_blob
  blob.open do |input|
    variation.transform(input) do |output|
      yield io: output, filename: "#{blob.filename.base}.#{variation.format.downcase}",
        content_type: variation.content_type, service_name: blob.service.name
    end
  end
end