Complex example.rb

require 'open-uri'
require 'prawn'
require 'prawn/measurement_extensions'
require_relative 'logging'

class RDIRenderer
  include Singleton, Logging

  @pdf = nil
  @nutri_object = nil
  @associated_product = nil
  @data_object = nil
  @min_font_sizes = {}

  def render_rdi(pdf, nutri_object, associated_product)

    @pdf = pdf
    @nutri_object = nutri_object
    @associated_product = associated_product
    @min_font_sizes = {title: 100, value: 100, percentage: 100} # Set some high default values

    # Get the binding's ACTUAL value from the product data
    bound_attribute = @associated_product['fields'].find { |field| field['binding'] == @nutri_object['binding'] }

    # There is no data in the product that will render this item, so ignore it
    return if bound_attribute.nil?

    # Don't render anything, as it requires data
    return if bound_attribute['data'].nil?

    # Check that the data is an object
    return unless bound_attribute['data'].is_a?(Hash)

    @data_object = bound_attribute['data']

    # Check for valid data before rendering
    return unless check_for_valid_content

    @x_position = @nutri_object['settings']['x'].to_f
    @y_position = @nutri_object['settings']['y'].to_f
    @rt = @nutri_object['settings']['rt'].to_f
    @width = @nutri_object['settings']['width'].to_f
    @height = @nutri_object['settings']['height'].to_f

    # Populate the color properties with the relevant values
    get_field_colors

    @pdf.rotate(-@rt, :origin => [@x_position + (@width / 2.0), -(@y_position + (@height / 2.0))]) do
      # Work out the current ratio of width to height
      aspect_ratio = @width / @height

      # Check the proportions of this control match
      # the expected (they probably wont!)
      if aspect_ratio > 2.37
        # The control is too SHORT
        new_width = @height * 2.37
        # Adjust the X value to compensate
        @x_position += (@width - new_width) / 2
        # Save the new width
        @width = new_width
      elsif aspect_ratio < 2.37
        # The control is too WIDE
        new_height = @width / 2.37
        # Adjust the Y value to compensate
        @y_position += (@height - new_height) / 2
        # Save the new height
        @height = new_height
      end

      @pdf.translate(@x_position, -@y_position) do

        # Render the bottom text and take note of the font size used,
        # as we need to use the same font size for the top
        box = Prawn::Text::Formatted::Box.new(
            [{text: 'of your reference intake'}],
            document: @pdf,
            at: [@width / 4, -((@height / 100) * 84.55)],
            width: @width / 2,
            height: (@height / 100) * 15.45,
            overflow: :shrink_to_fit,
            align: :center,
            valign: :center,
            min_font_size: 1,
            disable_wrap_by_char: true
        )
        box.render # Render the text box
        heading_font_size = box.instance_eval { @font_size }

        # Set the font size for the top heading
        @pdf.font_size heading_font_size

        # Top text
        @pdf.text_box(
            "Each #{@data_object['portionText']} contains",
            at: [@width / 4, 0],
            width: @width / 2,
            height: (@height / 100) * 15.45,
            overflow: :shrink_to_fit,
            align: :center,
            valign: :center,
            min_font_size: 1,
            disable_wrap_by_char: true
        )

        bound_attribute['data']['values'].each_pair do |key, value|
          @pdf.translate((@width / 5) * value[:index], -((@height / 100) * 84.55)) do
            if key == 'energy'
              value_text = "#{bound_attribute['data']['values'][key][:value]['kJ']} kJ\n#{bound_attribute['data']['values'][key][:value]['kcal']}kcal"
            else
              value_text = "#{bound_attribute['data']['values'][key][:value]}g"
            end
            render_lozenge({}, @width / 5, (@height / 100) * 69.1, value[:color], key.capitalize, value_text, value[:percentage])
          end
        end

        bound_attribute['data']['values'].each_pair do |key, value|
          @pdf.translate((@width / 5) * value[:index], -((@height / 100) * 84.55)) do
            if key == 'energy'
              value_text = "#{bound_attribute['data']['values'][key][:value]['kJ']} kJ\n#{bound_attribute['data']['values'][key][:value]['kcal']}kcal"
            else
              value_text = "#{bound_attribute['data']['values'][key][:value]}g"
            end
            render_lozenge(@min_font_sizes, @width / 5, (@height / 100) * 69.1, value[:color], key.capitalize, value_text, value[:percentage])
          end
        end
      end
    end
  end

  def check_for_valid_content
    # Check for values that are invalid
    return false if @data_object['portionSize'] == 0

    all_zero = true
    @data_object['values'].each do |key, value|
      if value.is_a?(Hash)
        if value['kJ'] != 0 || value['kcal'] != 0
          all_zero = false
          break
        end
      else
        if value != 0
          all_zero = false
          break
        end
      end
    end

    # If all the values are zero, then don't draw it!
    all_zero ? false : true
  end

  def render_lozenge (font_sizes, width, height, color, title, value, percentage)
    # Only render the outline if it's a "real" render
    unless font_sizes.empty?
      # Draw the color polygon
      @pdf.move_to 0, (height / 10) * 3.33
      @pdf.line_to width, (height / 10) * 3.33
      @pdf.line_to width, (height / 10) * 1.5
      @pdf.curve_to [0, (height / 10) * 1.5], :bounds => [[width - ((height / 10) * 1.5), 0], [(height / 10) * 1.5, 0]]
      @pdf.line_to 0, (height / 10) * 3.33
      @pdf.fill_color color
      @pdf.fill
      @pdf.fill_color '000000'

      # Draw the outlines
      @pdf.stroke do
        # Set the join style to rounded to make it nice and smooth
        @pdf.join_style = :round

        # Draw the main outline
        @pdf.move_to 0, (height / 10) * 1.5
        @pdf.curve_to [width, (height / 10) * 1.5], :bounds => [[(height / 10) * 1.5, 0], [width - ((height / 10) * 1.5), 0]]
        @pdf.line_to width, (height / 10) * 8.5
        @pdf.curve_to [0, (height / 10) * 8.5], :bounds => [[width - ((height / 10) * 1.5), height], [(height / 10) * 1.5, height]]
        @pdf.line_to 0, (height / 10) * 1.5

        # Draw the divider line
        @pdf.move_to 0, (height / 10) * 3.33
        @pdf.line_to width, (height / 10) * 3.33
      end
    end

    @pdf.font_size 40

    logger.info("font_sizes: #{font_sizes}\n@min_font_sizes: #{@min_font_sizes}")

    # Title text
    box = Prawn::Text::Formatted::Box.new(
        get_font_value(title, font_sizes[:title]),
        document: @pdf,
        at: [(width / 100) * 5, (height / 10) * 8.75],
        width: (width / 100) * 90,
        height: (height / 10) * 1.3,
        overflow: :shrink_to_fit,
        align: :center,
        valign: :center,
        min_font_size: 1,
        disable_wrap_by_char: true
    )
    font_sizes[:title].nil? ? box.render(dry_run: true) : box.render
    if box.instance_eval { @font_size } < @min_font_sizes[:title]
      @min_font_sizes[:title] = box.instance_eval { @font_size }
    end

    # Value text
    box = Prawn::Text::Formatted::Box.new(
        get_font_value(value, font_sizes[:value]),
        document: @pdf,
        at: [(width / 100) * 5, (height / 10) * 7.15],
        width: (width / 100) * 90,
        height: (height / 10) * 3.55,
        overflow: :shrink_to_fit,
        style: :bold,
        align: :center,
        valign: :center,
        min_font_size: 1,
        disable_wrap_by_char: true
    )
    font_sizes[:value].nil? ? box.render(dry_run: true) : box.render
    if box.instance_eval { @font_size } < @min_font_sizes[:value] && value.lines.count == 1
      @min_font_sizes[:value] = box.instance_eval { @font_size }
    end

    # Percentage text
    box = Prawn::Text::Formatted::Box.new(
        get_font_value(percentage, font_sizes[:percentage]),
        document: @pdf,
        at: [(width / 100) * 10, (height / 10) * 3.05],
        width: (width / 100) * 80,
        height: (height / 10) * 2,
        overflow: :shrink_to_fit,
        style: :bold,
        align: :center,
        valign: :center,
        min_font_size: 1,
        disable_wrap_by_char: true
    )
    font_sizes[:percentage].nil? ? box.render(dry_run: true) : box.render
    if box.instance_eval { @font_size } < @min_font_sizes[:percentage]
      @min_font_sizes[:percentage] = box.instance_eval { @font_size }
    end
  end

  def get_field_colors

    if @data_object['portionSize'].is_a?(String)
      @data_object['portionSize'] = @data_object['portionSize'].to_f
    end

    @data_object['values'].each do |key, value|

      # Convert any strings to floats
      if value.is_a?(String)
        value = value.to_f
      end

      if value.is_a?(Hash)
        if value['kcal'].is_a?(String)
          value['kcal'] = value['kcal'].to_f
        end
        if value['kJ'].is_a?(String)
          value['kJ'] = value['kJ'].to_f
        end
        adjusted_value = value['kJ'] / (@data_object['portionSize'] / 100.0)
      else
        adjusted_value = value / (@data_object['portionSize'] / 100.0)
      end

      case key
        when 'energy'
          @data_object['values'][key] = {value: value, color: 'FFFFFF'}
          @data_object['values'][key][:percentage] = "#{((value['kJ'] / 8400.0) * 100).round}%"
          @data_object['values'][key][:index] = 0
        when 'fat'
          if @data_object['type'] === 'food'
            if adjusted_value > 17.5 || value > 21
              @data_object['values'][key] = {value: value, color: 'e16b5f'}
            elsif adjusted_value > 3 && adjusted_value <= 17.5
              @data_object['values'][key] = {value: value, color: 'f7ca87'}
            elsif adjusted_value <= 3.0
              @data_object['values'][key] = {value: value, color: 'a7cd7e'}
            end
          else
            if adjusted_value > 8.75 || value > 10.5
              @data_object['values'][key] = {value: value, color: 'e16b5f'}
            elsif adjusted_value > 1.5 && adjusted_value <= 8.75
              @data_object['values'][key] = {value: value, color: 'f7ca87'}
            elsif adjusted_value <= 1.5
              @data_object['values'][key] = {value: value, color: 'a7cd7e'}
            end
          end
          @data_object['values'][key][:percentage] = "#{((value / 70.0) * 100).round}%"
          @data_object['values'][key][:index] = 1
        when 'saturates'
          if @data_object['type'] === 'food'
            if adjusted_value > 5 || value > 6
              @data_object['values'][key] = {value: value, color: 'e16b5f'}
            elsif adjusted_value > 1.5 && adjusted_value <= 5
              @data_object['values'][key] = {value: value, color: 'f7ca87'}
            elsif adjusted_value <= 1.5
              @data_object['values'][key] = {value: value, color: 'a7cd7e'}
            end
          else
            if adjusted_value > 2.5 || value > 3
              @data_object['values'][key] = {value: value, color: 'e16b5f'}
            elsif adjusted_value > 0.75 && adjusted_value <= 2.5
              @data_object['values'][key] = {value: value, color: 'f7ca87'}
            elsif adjusted_value <= 0.75
              @data_object['values'][key] = {value: value, color: 'a7cd7e'}
            end
          end
          @data_object['values'][key][:percentage] = "#{((value / 20.0) * 100).round}%"
          @data_object['values'][key][:index] = 2
        when 'sugars'
          if @data_object['type'] === 'food'
            if adjusted_value > 22.5 || value > 27
              @data_object['values'][key] = {value: value, color: 'e16b5f'}
            elsif adjusted_value > 5 && adjusted_value <= 22.5
              @data_object['values'][key] = {value: value, color: 'f7ca87'}
            elsif adjusted_value <= 5
              @data_object['values'][key] = {value: value, color: 'a7cd7e'}
            end
          else
            if adjusted_value > 11.25 || value > 13.5
              @data_object['values'][key] = {value: value, color: 'e16b5f'}
            elsif adjusted_value > 2.5 && adjusted_value <= 11.25
              @data_object['values'][key] = {value: value, color: 'f7ca87'}
            elsif adjusted_value <= 2.5
              @data_object['values'][key] = {value: value, color: 'a7cd7e'}
            end
          end
          @data_object['values'][key][:percentage] = "#{((value / 90.0) * 100).round}%"
          @data_object['values'][key][:index] = 3
        when 'salt'
          if @data_object['type'] === 'food'
            if adjusted_value > 1.5 || value > 1.8
              @data_object['values'][key] = {value: value, color: 'e16b5f'}
            elsif adjusted_value > 0.3 && adjusted_value <= 1.5
              @data_object['values'][key] = {value: value, color: 'f7ca87'}
            elsif adjusted_value <= 0.3
              @data_object['values'][key] = {value: value, color: 'a7cd7e'}
            end
          else
            if adjusted_value > 0.75 || value > 0.9
              @data_object['values'][key] = {value: value, color: 'e16b5f'}
            elsif adjusted_value > 0.3 && adjusted_value <= 0.75
              @data_object['values'][key] = {value: value, color: 'f7ca87'}
            elsif adjusted_value <= 0.3
              @data_object['values'][key] = {value: value, color: 'a7cd7e'}
            end
          end
          @data_object['values'][key][:percentage] = "#{((value / 6.0) * 100).round}%"
          @data_object['values'][key][:index] = 4
        else
          logger.info("Field type #{key} was not a recognised type!")
      end
    end
  end

  def get_font_value(text, font_size)
    (font_size.nil? || text.lines.count > 1) ? [{text: text}] : [{text: text, size: font_size}]
  end
end