class YARD::I18n::PotGenerator

def current_time
  @current_time ||= Time.now
end

def escape_message_id(message_id)
  message_id.gsub(/(\\|")/) do
    special_character = $1
    "\\#{special_character}"
  end
end

def extract_documents(object)
  return if @extracted_objects.key?(object)
  @extracted_objects[object] = true
  case object
  when CodeObjects::NamespaceObject
    object.children.each do |child|
      extract_documents(child)
    end
  end
  if object.group
    message = register_message(object.group)
    object.files.each do |path, line|
      message.add_location(path, line)
    end
    message.add_comment(object.path) unless object.path.empty?
  end
  docstring = object.docstring
  unless docstring.empty?
    text = Text.new(StringIO.new(docstring))
    text.extract_messages do |type, *args|
      case type
      when :paragraph
        paragraph, line_no = *args
        message = register_message(paragraph.rstrip)
        object.files.each do |path, line|
          message.add_location(path, (docstring.line || line) + line_no)
        end
        message.add_comment(object.path) unless object.path.empty?
      else
        raise "should not reach here: unexpected type: #{type}"
      end
    end
  end
  docstring.tags.each do |tag|
    extract_tag_documents(tag)
  end
end

def extract_paragraphs(file)
  File.open(file.filename) do |input|
    text = Text.new(input, :have_header => true)
    text.extract_messages do |type, *args|
      case type
      when :attribute
        name, value, line_no = *args
        message = register_message(value)
        message.add_location(file.filename, line_no)
        message.add_comment(name)
      when :paragraph
        paragraph, line_no = *args
        message = register_message(paragraph.rstrip)
        message.add_location(file.filename, line_no)
      else
        raise "should not reach here: unexpected type: #{type}"
      end
    end
  end
end

def extract_tag_documents(tag)
  extract_tag_name(tag)
  extract_tag_text(tag)
  extract_documents(tag) if Tags::OverloadTag === tag
end

def extract_tag_name(tag)
  return if tag.name.nil?
  return if tag.name.is_a?(String) && tag.name.empty?
  key = "tag|#{tag.tag_name}|#{tag.name}"
  message = register_message(key)
  tag.object.files.each do |path, line|
    message.add_location(path, line)
  end
  tag_label = String.new("@#{tag.tag_name}")
  tag_label << " [#{tag.types.join(', ')}]" if tag.types
  message.add_comment(tag_label)
end

def extract_tag_text(tag)
  return if tag.text.nil?
  return if tag.text.empty?
  message = register_message(tag.text)
  tag.object.files.each do |path, line|
    message.add_location(path, line)
  end
  tag_label = String.new("@#{tag.tag_name}")
  tag_label << " [#{tag.types.join(', ')}]" if tag.types
  tag_label << " #{tag.name}" if tag.name
  message.add_comment(tag_label)
end

def generate
  pot = String.new(header)
  sorted_messages = @messages.sort_by do |message|
    sorted_locations = message.locations.sort
    sorted_locations.first || []
  end
  sorted_messages.each do |message|
    generate_message(pot, message)
  end
  pot
end

def generate_message(pot, message)
  message.comments.sort.each do |comment|
    pot << "# #{comment}\n" unless comment.empty?
  end
  message.locations.sort.each do |path, line|
    pot << "#: #{@relative_base_path}/#{path}:#{line}\n"
  end
  escaped_message_id = escape_message_id(message.id)
  escaped_message_id = escaped_message_id.gsub(/\n/, "\\\\n\"\n\"")
  pot << "msgid \"#{escaped_message_id}\"\n"
  pot << "msgstr \"\"\n"
  pot << "\n"
  pot
end

def generate_pot_creation_date_value
  current_time.strftime("%Y-%m-%d %H:%M%z")
end

def header
  <<-EOH
 DESCRIPTIVE TITLE.
right (C) YEAR THE PACKAGE'S COPYRIGHT HOLDER
 file is distributed under the same license as the PACKAGE package.
T AUTHOR <EMAIL@ADDRESS>, YEAR.
zy
""
 ""
ct-Id-Version: PACKAGE VERSION\\n"
t-Msgid-Bugs-To: \\n"
reation-Date: #{generate_pot_creation_date_value}\\n"
vision-Date: YEAR-MO-DA HO:MI+ZONE\\n"
Translator: FULL NAME <EMAIL@ADDRESS>\\n"
age-Team: LANGUAGE <LL@li.org>\\n"
age: \\n"
Version: 1.0\\n"
nt-Type: text/plain; charset=UTF-8\\n"
nt-Transfer-Encoding: 8bit\\n"
end

def initialize(relative_base_path)
  @relative_base_path = relative_base_path
  @extracted_objects = {}
  @messages = Messages.new
end

def parse_files(files)
  files.each do |file|
    extract_paragraphs(file)
  end
end

def parse_objects(objects)
  objects.each do |object|
    extract_documents(object)
  end
end

def register_message(id)
  @messages.register(id)
end