# https://github.com/mraible/infoq-mini-book/blob/master/src/main/ruby/asciidoctor-pdf-extensions.rb

class CustomPDFConverter < (Asciidoctor::Converter.for 'pdf')
  register_for 'pdf'

  def layout_part_title node, title, opts = {}
    fill_absolute_bounds 'EEEEEE'
    move_down 25
    typeset_text title, (calc_line_metrics 1.5), color: '000000', inline_format: true, align: :left, size: 36
    move_down 5
    # Remove header
    page.instance_variable_set :@imported_page, true
  end

  # Override the built-in layout_toc to move colophon before front of table of contents
  # NOTE we assume that the colophon fits on a single page
  def layout_toc doc, num_levels = 2, toc_page_number = 2, start_y = nil, num_front_matter_pages = 0
    go_to_page toc_page_number unless (page_number == toc_page_number) || scratch?
    if scratch?
      colophon = doc.find_by(context: :section) {|sect| sect.sectname == 'colophon' }
      if (colophon = colophon.first)
        doc.instance_variable_set :@colophon, colophon
        colophon.parent.blocks.delete colophon
      end
    else
      if (colophon = doc.instance_variable_get :@colophon)
        # if prepress book, consume blank page before table of contents
        go_to_page(page_number - 1) if @ppbook
        convert_section colophon
        go_to_page(page_number + 1)
      end
    end
    offset = colophon && !@ppbook ? 1 : 0
    toc_page_numbers = super doc, num_levels, (toc_page_number + offset), start_y, num_front_matter_pages
    scratch? ? ((toc_page_numbers.begin - offset)..toc_page_numbers.end) : toc_page_numbers
  end

  def layout_chapter_title node, title, opts = {}
	# Remove header
	page.instance_variable_set :@imported_page, true
    if (sect_id = node.id) == 'dedication' || sect_id == 'acknowledgements'
      layout_heading_custom title, align: :center
    elsif sect_id == 'colophon'
      #puts 'Processing ' + node.sectname + '...'
      if node.document.attr? 'media', 'prepress'
        move_down 150
      else
        move_down 250
      end
      layout_heading title, size: @theme.base_font_size
    elsif sect_id == 'preface' || sect_id == 'bibliography' || sect_id == 'index'
      super # default options, with no extra space
    elsif sect_id.include? 'chapter' # chapters
      #puts 'Processing ' + sect_id + '...'
      # use Akkurat font for all custom headings
      font 'Akkurat' do
        if node.document.attr? 'media', 'prepress'
          move_down 120
        else
          move_down 180
        end
        if @ppbook
          layout_heading 'PART', align: :right, size: 100, style: :normal
        else
          layout_heading 'PART', align: :right, size: 100, color: [91, 54, 8, 13], style: :normal
        end
        move_up 40

        part_number = 'ONE'
        if sect_id.include? 'chapter-2'
          part_number = 'TWO'
        elsif sect_id.include? 'chapter-3'
          part_number = 'THREE'
        end
        if @ppbook
          layout_heading part_number, align: :right, size: 100, style: :bold
          layout_heading title, align: :right, style: :normal, size: 30
        else
          layout_heading part_number, align: :right, size: 100, color: [42, 1, 83, 1], style: :bold
          layout_heading title, align: :right, color: [42, 1, 83, 1], style: :normal, size: 30
        end
      end

      bounds.move_past_bottom
    else
      move_down 50
      super # delegate to default implementation
      move_down 15
    end
  end
end