# Copyright 2025 Google LLC # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. require 'redcarpet' require 'nokogiri' module Pebble class TocGenerator def initialize(max_depth=-1) @max_depth = max_depth @markdown = TocMarkdown.new() @redcarpet = Redcarpet::Markdown.new(@markdown, fenced_code_blocks: true, autolink: true, tables: true, no_intra_emphasis: true, strikethrough: true, highlight: true) end def generate(content) @redcarpet.render(content) page_toc = @markdown.get_toc toc_array(toc_normalised(page_toc)) end private # Convert the ToC array of hashes into an array of array so that it can # be used in the Liquid template. def toc_array(array) array.map { |entry| [ entry[:id], entry[:title], entry[:level] ] } end # Normalised the ToC array by ensuring that the smallest level number is 1. def toc_normalised(array) min_level = 100 array.each { |entry| min_level = [ min_level, entry[:level] ].min } level_offset = min_level - 1 array.map { |entry| entry[:level] -= level_offset; entry }.select do |entry| @max_depth == -1 || entry[:level] <= @max_depth end end end class TocMarkdown < Redcarpet::Render::HTML def initialize() @toc = Array.new @depth = 0 super() end def get_toc() @toc end def header(text, header_level) text = Nokogiri::HTML(text).text if text.include?('<') entry = { title: text, id: text.slugize, level: header_level } @toc << entry "" end end end