post '/create' do # TODO
  protected!
  request.body.rewind # in case someone already read it

  to = []
  inReplyTo = ''
  content = []
  tag = []
  attachment = []

  url_regexp = %r{\Ahttps?://\S+\Z}
  mention_regexp = /\A@?\w+@\S+\Z/
  hashtag_regexp = /\A#\w+\Z/

  lines = request.body.read.each_line.to_a
  lines.each.with_index do |line, i|
    line.chomp!
    if i == 0
      to = line.split(/\s+/).collect do |word|
        case word
        when 'public'
          ['https://www.w3.org/ns/activitystreams#Public', FOLLOWERS_URL]
        when mention_regexp
          actor word
        when url_regexp
          word
        end
      end.flatten
    elsif i == 1 and line.match url_regexp
      inReplyTo = line
    elsif line == ''
      content << '<p>'
    elsif line.match(/\A==\Z/)
      attachment = lines[i + 1..-1].collect do |url|
        url.chomp!
        {
          'type' => 'Document',
          'mediaType' => media_type(url),
          'url' => url
        }
      end
      break
    else
      tags = line.split(/\s+/).grep(hashtag_regexp)
      tags.each do |name|
        tag_url = File.join(TAGS[:url], name.sub('#', ''))
        tag << {
          'type' => 'Hashtag',
          'href' => tag_url,
          'name' => name
        }
      end
      mentions = line.split(/\s+/).grep(mention_regexp)
      mentions.each do |mention|
        actor = actor(mention)
        tag << {
          'type' => 'Mention',
          'href' => actor,
          'name' => mention
        }
      end
      content << line
    end
  end

  object = {
    'to' => to,
    'type' => 'Note',
    'attributedTo' => ACTOR,
    'content' => "#{content.join("\n")}"
  }
  object['inReplyTo'] = inReplyTo unless inReplyTo.empty?
  object['attachment'] = attachment unless attachment.empty?
  object['tag'] = tag unless tag.empty?

  activity = outbox 'Create', object, to
  if activity['object']['tag']
    activity['object']['tag'].each do |tag|
      next unless tag['type'] == 'Hashtag'

      tag_path = File.join(TAGS[:dir], tag['name'].sub('#', '')) + '.json'
      next if File.exist? tag_path

      File.open(tag_path, 'w+') do |f|
        tag_collection = {
          '@context' => 'https://www.w3.org/ns/activitystreams',
          'id' => tag['href'],
          'type' => 'OrderedCollection',
          'totalItems' => 0,
          'orderedItems' => []
        }
        f.puts tag_collection.to_json
      end
    end
  end
  200
end