prawnpdf/prawn

# frozen_string_literal: true

require 'prawn/manual_builder'

Prawn::ManualBuilder::Chapter.new do
  title 'Nesting Bounding Boxes'

  text do
    prose <<~TEXT
      Normally when we provide the top left corner of a bounding box we express
      the coordinates relative to the margin box. This is not the case when we
      have nested bounding boxes. Once nested the inner bounding box
      coordinates are relative to the outer bounding box.

      This example shows some nested bounding boxes with fixed and stretchy
      heights. Note how the <code>cursor</code> method returns coordinates
      relative to the current bounding box.
    TEXT
  end

  example new_page: true do
    def box_content(string)
      text(string)
      transparent(0.5) { stroke_bounds }
    end

    gap = 20
    bounding_box([50, cursor], width: 400, height: 200) do
      box_content('Fixed height')

      bounding_box([gap, cursor - gap], width: 300) do
        text 'Stretchy height'

        bounding_box([gap, bounds.top - gap], width: 100) do
          text 'Stretchy height'
          transparent(0.5) do
            dash(1)
            stroke_bounds
            undash
          end
        end

        bounding_box([gap * 7, bounds.top - gap], width: 100, height: 50) do
          box_content('Fixed height')
        end

        transparent(0.5) do
          dash(1)
          stroke_bounds
          undash
        end
      end

      bounding_box([gap, cursor - gap], width: 300, height: 50) do
        box_content('Fixed height')
      end
    end
  end
end