```ruby
module Pageflow
  class PositionedFile
    attr_reader :file, :position_x, :position_y

    delegate :thumbnail_url, to: :file

    def initialize(file, position_x = nil, position_y = nil)
      @file = file
      @position_x = position_x.presence || 50
      @position_y = position_y.presence || 50
    end

    def ==(other)
      super(other) ||
        other == file ||
        (other.is_a?(PositionedFile) && other.file == file)
    end

    def to_model
      file
    end

    def self.wrap(file, position_x, position_y)
      file ? new(file, position_x, position_y) : nil
    end

    def self.null
      Null.new
    end

    class Null < PositionedFile
      def initialize
        super(nil)
      end

      def thumbnail_url(*args)
        ImageFile.new.attachment.url(*args)
      end

      def blank?
        true
      end
    end
  end
end
```

Align thumbnail_url in PositionedFile with ImageFile
user
```ruby
module Pageflow
  class PositionedFile
    attr_reader :file, :position_x, :position_y

    delegate :thumbnail_url, to: :file

    def initialize(file, position_x = nil, position_y = nil)
      @file = file
      @position_x = position_x.presence || 50
      @position_y = position_y.presence || 50
    end

    def ==(other)
      super(other) ||
        other == file ||
        (other.is_a?(PositionedFile) && other.file == file)
    end

    def to_model
      file
    end

    def self.wrap(file, position_x, position_y)
      file ? new(file, position_x, position_y) : nil
    end

    def self.null
      Null.new
    end

    class Null < PositionedFile
      def initialize
        super(nil)
      end

      def thumbnail_url(*args)
        ImageFile.new.thumbnail_url(*args)
      end

      def blank?
        true
      end
    end
  end
end
```
assistant