foodsoft/lib/order_pdf.rb

require "prawn/measurement_extensions"

class OrderPdf < Prawn::Document
  include ActionView::Helpers::NumberHelper

  def initialize(order, options = {})
    options[:page_size] ||= "A4"
    #options[:left_margin]   ||= 40
    #options[:right_margin]  ||= 40
    options[:top_margin]    ||= 50
    #options[:bottom_margin] ||= 40
    super(options)
    @order = order
  end

  def to_pdf
    # Define header
    repeat :all, dynamic: true do
      draw_text title, size: 10, style: :bold, at: [bounds.left, bounds.top+20] if title # Header
      draw_text I18n.t('lib.order_pdf.page', :number => page_number), size: 8, at: [bounds.left, bounds.bottom-10] # Footer
    end

    body  # Add content, which is defined in subclasses

    render  # Render pdf
  end

  # Helper method to test pdf via rails console: OrderByGroups.new(order).save_tmp
  def save_tmp
    File.open("#{Rails.root}/tmp/#{self.class.to_s.underscore}.pdf", 'w') {|f| f.write(to_pdf.force_encoding("UTF-8")) }
  end
end