Hugo to Asciidoctor

11 files changed, 379 insertions, 0 deletions

diff --git a/lib/command.rb b/lib/command.rb
new file mode 100644
index 0000000..81692b3
--- /dev/null
+++ b/lib/command.rb
@@ -0,0 +1,152 @@
+module NulDoc
+  class Command
+    def initialize(config)
+      @config = config
+      @content_dir = @config[:content_dir]
+      @dest_dir = @config[:dest_dir]
+      @template_dir = @config[:template_dir]
+      @parser = NulDoc::Parser.new(
+        {
+          'author' => @config[:author],
+          'site-copyright-year' => @config[:site_copyright_year],
+          'site-name' => @config[:site_name],
+          'source-highlighter' => 'rouge',
+          'reproducible' => true,
+          'sectids' => false,
+        },
+        @content_dir,
+        @template_dir,
+      )
+    end
+
+    def run
+      posts = generate_posts(@content_dir + '/posts')
+      generate_tags(posts)
+      generate_posts_list(posts)
+    end
+
+    private
+
+    def generate_posts(source_dir)
+      post_files = collect_post_files(source_dir)
+      posts = parse_posts(post_files)
+      output_posts(posts)
+      posts
+    end
+
+    def collect_post_files(source_dir)
+      file_paths = []
+      Dir.glob('**/*.adoc', base: source_dir, sort: true) do |path|
+        file_paths << "#{source_dir}/#{path}"
+      end
+      file_paths
+    end
+
+    def parse_posts(post_file_paths)
+      post_file_paths.map { @parser.parse_file(_1) }
+    end
+
+    def output_posts(posts)
+      posts.each do |post|
+        destination_file_path = post.attributes['source-file-path']
+          .sub(@content_dir, @dest_dir)
+          .sub('.adoc', '/index.html')
+        destination_dir = File.dirname(destination_file_path)
+        unless Dir.exist?(destination_dir)
+          FileUtils.makedirs(destination_dir)
+        end
+        open(destination_file_path, 'w') do |f|
+          f.puts(post.convert)
+        end
+      end
+    end
+
+    def generate_tags(posts)
+      tags_and_posts = collect_tags(posts)
+      tag_docs = build_tag_docs(tags_and_posts)
+      output_tags(tag_docs)
+    end
+
+    def collect_tags(posts)
+      tags_and_posts = {}
+      posts.each do |post|
+        post.attributes['tags'].each do |tag|
+          tags_and_posts[tag] ||= []
+          tags_and_posts[tag] << post
+        end
+      end
+      tags_and_posts
+        .transform_values {|posts|
+          posts.sort_by {|post|
+            post.attributes['revision-history'].first.date # created_at
+          }.reverse
+        }
+        .sort_by {|tag, _| tag.slug }
+        .to_h
+    end
+
+    def build_tag_docs(tags_and_posts)
+      tags_and_posts.map do |tag, posts|
+        [tag, build_tag_doc(tag, posts)]
+      end
+    end
+
+    def build_tag_doc(tag, posts)
+      erb = ERB.new(File.read(@template_dir + '/tag.html.erb'))
+      erb.result_with_hash({
+        tag: tag,
+        posts: posts,
+        author: @config[:author],
+        site_copyright_year: @config[:site_copyright_year],
+        site_name: @config[:site_name],
+        lang: 'ja-JP', # TODO
+        copyright_year: posts.last.attributes['revision-history'].first.date.year,
+        description: "タグ「#{tag.label}」のついた記事一覧",
+      })
+    end
+
+    def output_tags(tag_docs)
+      tag_docs.each do |tag, html|
+        destination_file_path = "#{@dest_dir}/tags/#{tag.slug}/index.html"
+        destination_dir = File.dirname(destination_file_path)
+        unless Dir.exist?(destination_dir)
+          FileUtils.makedirs(destination_dir)
+        end
+        open(destination_file_path, 'w') do |f|
+          f.puts(html)
+        end
+      end
+    end
+
+    def generate_posts_list(posts)
+      html = build_posts_list_doc(posts)
+      output_posts_list(html)
+    end
+
+    def build_posts_list_doc(posts)
+      erb = ERB.new(File.read(@template_dir + '/posts_list.html.erb'))
+      erb.result_with_hash({
+        posts: posts.reverse,
+        author: @config[:author],
+        site_copyright_year: @config[:site_copyright_year],
+        site_name: @config[:site_name],
+        lang: 'ja-JP', # TODO
+        copyright_year: @config[:site_copyright_year],
+        description: "記事一覧",
+        doctitle: "Posts",
+        header_title: "Posts",
+      })
+    end
+
+    def output_posts_list(html)
+      destination_file_path = "#{@dest_dir}/posts/index.html"
+      destination_dir = File.dirname(destination_file_path)
+      unless Dir.exist?(destination_dir)
+        FileUtils.makedirs(destination_dir)
+      end
+      open(destination_file_path, 'w') do |f|
+        f.puts(html)
+      end
+    end
+  end
+end
diff --git a/lib/extensions/document_title_processor.rb b/lib/extensions/document_title_processor.rb
new file mode 100644
index 0000000..fd25844
--- /dev/null
+++ b/lib/extensions/document_title_processor.rb
@@ -0,0 +1,15 @@
+module Nuldoc
+  module Extensions
+    class DocumentTitleProcessor < Asciidoctor::Extensions::TreeProcessor
+      def process(doc)
+        doc.title = substitute_document_title(doc.title)
+      end
+
+      private
+
+      def substitute_document_title(title)
+        title.sub(/\A\[(.+?)\] /, '【\1】')
+      end
+    end
+  end
+end
diff --git a/lib/extensions/lang_attribute_processor.rb b/lib/extensions/lang_attribute_processor.rb
new file mode 100644
index 0000000..65511bc
--- /dev/null
+++ b/lib/extensions/lang_attribute_processor.rb
@@ -0,0 +1,9 @@
+module Nuldoc
+  module Extensions
+    class LangAttributeProcessor < Asciidoctor::Extensions::TreeProcessor
+      def process(doc)
+        doc.attributes['lang'] ||= 'ja-JP'
+      end
+    end
+  end
+end
diff --git a/lib/extensions/revision_history_processor.rb b/lib/extensions/revision_history_processor.rb
new file mode 100644
index 0000000..f416de0
--- /dev/null
+++ b/lib/extensions/revision_history_processor.rb
@@ -0,0 +1,27 @@
+module Nuldoc
+  module Extensions
+    class RevisionHistoryProcessor < Asciidoctor::Extensions::TreeProcessor
+      def process(doc)
+        revisions = []
+        i = 1
+        loop do
+          break unless (rev = doc.attributes["revision-#{i}"])
+          revisions << parse_revision(rev)
+          i += 1
+        end
+        doc.attributes['revision-history'] = revisions
+      end
+
+      private
+
+      def parse_revision(rev)
+        m = rev.match(/\A(\d\d\d\d-\d\d-\d\d) (.*)\z/)
+        raise unless m
+        Revision.new(
+          date: Date.parse(m[1], '%Y-%m-%d'),
+          remark: m[2],
+        )
+      end
+    end
+  end
+end
diff --git a/lib/extensions/section_id_validator.rb b/lib/extensions/section_id_validator.rb
new file mode 100644
index 0000000..2ad496c
--- /dev/null
+++ b/lib/extensions/section_id_validator.rb
@@ -0,0 +1,29 @@
+module Nuldoc
+  module Extensions
+    class SectionIdValidator < Asciidoctor::Extensions::TreeProcessor
+      def process(doc)
+        errors = []
+        (doc.find_by(context: :section) {_1.level > 0}).each do |section|
+          errors << validate_section(section)
+        end
+        error_message = errors.compact.join("\n")
+        unless error_message.empty?
+          raise "SectionIdValidator (#{doc.attributes['source-file-path']}):\n#{error_message}"
+        end
+      end
+
+      private
+
+      def validate_section(section)
+        id = section.id
+        unless id
+          return "Section '#{section.title}': each section MUST have an id."
+        end
+        unless id.match?(/\A[-0-9a-z]+\z/)
+          return "Section '#{section.title}' (##{id}): section id MUST consist of either hyphen, digits or lowercases."
+        end
+        nil
+      end
+    end
+  end
+end
diff --git a/lib/extensions/source_id_processor.rb b/lib/extensions/source_id_processor.rb
new file mode 100644
index 0000000..13813e0
--- /dev/null
+++ b/lib/extensions/source_id_processor.rb
@@ -0,0 +1,12 @@
+module Nuldoc
+  module Extensions
+    class SourceIdProcessor < Asciidoctor::Extensions::TreeProcessor
+      def process(doc)
+        errors = []
+        (doc.find_by(context: :listing) {_1.style == 'source'}).each do |source|
+          source.id = "source.#{source.id}"
+        end
+      end
+    end
+  end
+end
diff --git a/lib/extensions/source_id_validator.rb b/lib/extensions/source_id_validator.rb
new file mode 100644
index 0000000..6e04deb
--- /dev/null
+++ b/lib/extensions/source_id_validator.rb
@@ -0,0 +1,32 @@
+module Nuldoc
+  module Extensions
+    class SourceIdValidator < Asciidoctor::Extensions::TreeProcessor
+      def process(doc)
+        errors = []
+        (doc.find_by(context: :listing) {_1.style == 'source'}).each do |source|
+          errors << validate_section(source)
+        end
+        error_message = errors.compact.join("\n")
+        unless error_message.empty?
+          raise "SourceIdValidator (#{doc.attributes['source-file-path']}):\n#{error_message}"
+        end
+      end
+
+      private
+
+      def validate_section(source)
+        id = source.id
+        unless id
+          return "Each source MUST have an id."
+        end
+        if id.start_with?('source.')
+          return "Source id (##{id}) MUST NOT start with 'source.', which is appended by `nul`."
+        end
+        unless id.match?(/\A[-0-9a-z]+\z/)
+          return "Source id (##{id}) MUST consist of either hypen, digits or lowercases."
+        end
+        nil
+      end
+    end
+  end
+end
diff --git a/lib/extensions/tags_processor.rb b/lib/extensions/tags_processor.rb
new file mode 100644
index 0000000..efbd2a8
--- /dev/null
+++ b/lib/extensions/tags_processor.rb
@@ -0,0 +1,20 @@
+module Nuldoc
+  module Extensions
+    class TagsProcessor < Asciidoctor::Extensions::TreeProcessor
+      def process(doc)
+        doc.attributes['tags'] = convert_tags(doc.attributes['tags'])
+      end
+
+      private
+
+      def convert_tags(tags)
+        return [] unless tags
+
+        tags
+          .split(',')
+          .map(&:strip)
+          .map { Tag.from_slug(_1) }
+      end
+    end
+  end
+end
diff --git a/lib/parser.rb b/lib/parser.rb
new file mode 100644
index 0000000..8ae3303
--- /dev/null
+++ b/lib/parser.rb
@@ -0,0 +1,54 @@
+module NulDoc
+  class Parser
+    def initialize(common_attributes, content_dir, template_dir)
+      @common_attributes = common_attributes
+      @content_dir = content_dir
+      @template_dir = template_dir
+    end
+
+    def parse_file(file_path)
+      Asciidoctor.load_file(
+        file_path,
+        backend: :html5,
+        doctype: :article,
+        standalone: true,
+        safe: :unsafe,
+        template_dirs: [@template_dir],
+        template_engine: 'erb',
+        attributes: @common_attributes.merge({
+          'source-file-path' => file_path,
+          'href' => file_path.sub(@content_dir, '').sub('.adoc', '/'),
+        }),
+        extension_registry: Asciidoctor::Extensions.create do
+          tree_processor Nuldoc::Extensions::RevisionHistoryProcessor
+          tree_processor Nuldoc::Extensions::DocumentTitleProcessor
+          tree_processor Nuldoc::Extensions::LangAttributeProcessor
+          # tree_processor Nuldoc::Extensions::SectionIdValidator
+          # tree_processor Nuldoc::Extensions::SourceIdValidator
+          tree_processor Nuldoc::Extensions::TagsProcessor
+
+          # MUST BE AT THE END
+          tree_processor Nuldoc::Extensions::SourceIdProcessor
+        end,
+      )
+    end
+
+    def parse_string(s, copyright_year)
+      Asciidoctor.convert(
+        s,
+        backend: :html5,
+        doctype: :article,
+        safe: :unsafe,
+        template_dirs: [@template_dir],
+        template_engine: 'erb',
+        attributes: @common_attributes.merge({
+          'copyright-year' => copyright_year,
+        }),
+        extension_registry: Asciidoctor::Extensions.create do
+          tree_processor Nuldoc::Extensions::LangAttributeProcessor
+          tree_processor Nuldoc::Extensions::TagsProcessor
+        end,
+      )
+    end
+  end
+end
diff --git a/lib/revision.rb b/lib/revision.rb
new file mode 100644
index 0000000..b986a14
--- /dev/null
+++ b/lib/revision.rb
@@ -0,0 +1,3 @@
+module Nuldoc
+  Revision = Struct.new(:date, :remark, keyword_init: true)
+end
diff --git a/lib/tag.rb b/lib/tag.rb
new file mode 100644
index 0000000..a7c13b2
--- /dev/null
+++ b/lib/tag.rb
@@ -0,0 +1,26 @@
+module Nuldoc
+  Tag = Struct.new(:slug, :label, keyword_init: true) do
+    LABELS = {
+      'conference'   => 'カンファレンス',
+      'cpp'          => 'C++',
+      'cpp17'        => 'C++ 17',
+      'note-to-self' => '備忘録',
+      'php'          => 'PHP',
+      'phpcon'       => 'PHP カンファレンス',
+      'phperkaigi'   => 'PHPerKaigi',
+      'python'       => 'Python',
+      'python3'      => 'Python 3',
+      'ruby'         => 'Ruby',
+      'ruby3'        => 'Ruby 3',
+      'rust'         => 'Rust',
+      'vim'          => 'Vim',
+    }
+
+    def self.from_slug(slug)
+      Tag.new(
+        slug: slug,
+        label: (LABELS[slug] || raise("No label for tag '#{slug}'")),
+      )
+    end
+  end
+end