prawnpdf/prawn

# frozen_string_literal: true

require 'prawn/manual_builder'

Prawn::ManualBuilder::Chapter.new do
  title 'Adding a Subsection to the Outline Tree'

  text do
    prose <<~TEXT
      We have already seen how to define an outline tree sequentially.

      If you'd like to add nodes to the middle of an outline tree the
      <code>add_subsection_to</code> may help you.

      It allows you to insert sections to the outline tree at any point. Just
      provide the <code>title</code> of the parent section, the
      <code>position</code> you want the new subsection to be inserted
      <code>:first</code> or <code>:last</code> (defaults to
      <code>:last</code>) and a block to declare the subsection.

      The <code>add_subsection_to</code> block doesn't necessarily create new
      sections, it may also create new pages.

      If the parent title provided is the title of a page. The page will be
      converted into a section to receive the subsection created.
    TEXT
  end

  example eval: false do
    # First we create 10 pages and some default outline
    (1..10).each do |index|
      text "Page #{index}"
      start_new_page
    end

    outline.define do
      section('Section 1', destination: 1) do
        page title: 'Page 2', destination: 2
        page title: 'Page 3', destination: 3
      end
    end

    # Now we will start adding nodes to the previous outline
    outline.add_subsection_to('Section 1', :first) do
      outline.section('Added later - first position') do
        outline.page(title: 'Page 4', destination: 4)
        outline.page(title: 'Page 5', destination: 5)
      end
    end

    outline.add_subsection_to('Section 1') do
      outline.page(title: 'Added later - last position', destination: 6)
    end

    outline.add_subsection_to('Added later - first position') do
      outline.page(title: 'Another page added later', destination: 7)
    end

    # The title provided is for a page which will be converted into a section
    outline.add_subsection_to('Page 3') do
      outline.page(title: 'Last page added', destination: 8)
    end
  end
end