Generate barcode SVG for ruby

barcode_helper.rb

# include BarcodeHelper
# call svg_barcode method in view
# e.g. <p><%= svg_barcode('12345') %></p>
# You shouuld implement Barcode class whith returns barcode encoding from string.

module BarcodeHelper
  def svg_barcode(token, options = {})
    xdim = (options[:xdim] || 2).to_i
    margin = pick_margin_from(options)
    height = (options[:height] || 80).to_i
    bc = Barcode.new(token)
    content_tag :svg,
                width: bc.width * xdim + margin[:left] + margin[:right],
                height: height + margin[:top] + margin[:bottom] do
      bc.encoding_array.each do |offset, width|
        concat content_tag :rect, '',
                           x: margin[:left] + offset * xdim, y: margin[:top],
                           width: width * xdim, height: height
      end
    end
  end
  def pick_margin_from(options)
    margin = options[:margin] || {}
    margin[:top] ||= 0
    margin[:bottom] ||= 0
    margin[:left] ||= 0
    margin[:right] ||= 0
    margin[:top] = options[:margin_top] if options[:margin_top]
    margin[:bottom] = options[:margin_bottom] if options[:margin_bottom]
    margin[:left] = options[:margin_left] if options[:margin_left]
    margin[:right] = options[:margin_right] if options[:margin_right]
    margin
  end
end