Import the pebble dev site into devsite/

devsite/lib/toc_generator.rb

@@ -0,0 +1,81 @@
+# 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