#153 PDFs with Prawn (revised)

gem 'prawn'

Mime::Type.register "application/pdf", :pdf

def show
  @order = Order.find(params[:id])
  respond_to do |format|
    format.html
    format.pdf do
      pdf = OrderPdf.new(@order, view_context)
      send_data pdf.render, filename: "order_#{@order.order_number}.pdf",
                            type: "application/pdf",
                            disposition: "inline"
    end
  end
end

class OrderPdf < Prawn::Document
  def initialize(order, view)
    super(top_margin: 70)
    @order = order
    @view = view
    order_number
    line_items
    total_price
  end
  
  def order_number
    text "Order \##{@order.order_number}", size: 30, style: :bold
  end
  
  def line_items
    move_down 20
    table line_item_rows do
      row(0).font_style = :bold
      columns(1..3).align = :right
      self.row_colors = ["DDDDDD", "FFFFFF"]
      self.header = true
    end
  end

  def line_item_rows
    [["Product", "Qty", "Unit Price", "Full Price"]] +
    @order.line_items.map do |item|
      [item.name, item.quantity, price(item.unit_price), price(item.full_price)]
    end
  end
  
  def price(num)
    @view.number_to_currency(num)
  end
  
  def total_price
    move_down 15
    text "Total Price: #{price(@order.total_price)}", size: 16, style: :bold
  end
end

<p><%= link_to "Printable Receipt (PDF)", order_path(@order, format: "pdf") %></p>