Contents

module Tocer
  # Builds a table of contents for a Markdown document.
  class Builder
    def initialize lines, label: "# Table of Contents", comment_block: Elements::CommentBlock
      @lines = lines
      @label = label
      @comment_block = comment_block.new
      @url_count = Hash.new { |hash, key| hash[key] = 0 }
    end

    def headers
      lines.select { |line| line.start_with? Parsers::Header.punctuation }
    end

    def build
      return "" if headers.empty?

      content = "#{comment_block.start}\n\n"
      content << "#{label}\n\n"
      content << headers_as_links.join("\n")
      content << "\n\n#{comment_block.finish}\n\n"
    end

    private

    attr_reader :lines, :label, :comment_block, :url_count

    def acquire_transfomer header
      case
        when header =~ /\[.+\]\(.+\)/
          Transformers::Link.new header
        else
          Transformers::Text.new header
      end
    end

    def url_suffix url
      url_count[url].zero? ? "" : url_count[url]
    end

    def transform header
      transformer = acquire_transfomer header
      link = transformer.transform url_suffix: url_suffix(transformer.url)
      url_count[transformer.url] += 1
      link
    end

    def headers_as_links
      headers.map { |header| transform header }
    end
  end
end

Version data entries

2 entries across 2 versions & 1 rubygems

Version	Path
tocer-2.0.0	lib/tocer/builder.rb
tocer-1.0.0	lib/tocer/builder.rb