lib/banzai/filter/inline_diff_filter.rb


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26

module Banzai
  module Filter
    class InlineDiffFilter < HTML::Pipeline::Filter
      IGNORED_ANCESTOR_TAGS = %w[pre code tt].to_set

      def call
        search_text_nodes(doc).each do |node|
          next if has_ancestor?(node, IGNORED_ANCESTOR_TAGS)

          content = node.to_html
          html_content = inline_diff_filter(content)

          next if content == html_content

          node.replace(html_content)
        end
        doc
      end

      def inline_diff_filter(text)
        html_content = text.gsub(/(?:\[\-(.*?)\-\]|\{\-(.*?)\-\})/, '<span class="idiff left right deletion">\1\2</span>')
        html_content.gsub(/(?:\[\+(.*?)\+\]|\{\+(.*?)\+\})/, '<span class="idiff left right addition">\1\2</span>')
      end
    end
  end
end