class LetsEncryptWorker
  class NotAuthorizedYetError < StandardError; end
  class VerificationTimeoutError < StandardError; end
  class VerifyNotFoundWithDomain < StandardError; end
  include Sidekiq::Worker
  sidekiq_options queue: :lets_encrypt_worker, retry: 5, backtrace: true

  sidekiq_retry_in do |count|
    1.hour.to_i
  end

  def letsencrypt
    Acme::Client.new(
      private_key: OpenSSL::PKey::RSA.new(File.read($config['letsencrypt_key'])),
      endpoint: $config['letsencrypt_endpoint']
    )
  end

  def perform(site_id)
    # Dispose of dupes
    queue = Sidekiq::Queue.new self.class.sidekiq_options_hash['queue']
    queue.each do |job|
      if job.args == [site_id] && job.jid != jid
        job.delete
      end
    end

    site = Site[site_id]
    return if site.domain.blank? || site.is_deleted || site.is_banned

    domains = [site.domain, "www.#{site.domain}"]

    domains.each_with_index do |domain, index|
      auth = letsencrypt.authorize domain: domain
      challenge = auth.http01

      FileUtils.mkdir_p File.join(site.base_files_path, File.dirname(challenge.filename)) if index == 0
      File.write File.join(site.base_files_path, challenge.filename), challenge.file_content

      # Ensure that both domains work before sending request. Let's Encrypt has a low
      # pending request limit, and it takes one week (!) to flush out.
      sleep 2
      challenge_url = "#{domain}/#{challenge.filename}"
      ["http://#{challenge_url}", "http://www.#{challenge_url}"].each do |url|
        res = HTTP.follow.get(url)
        raise VerifyNotFoundWithDomain unless res.status == 200
      end

      challenge.request_verification

      sleep 60
      attempts = 0

      begin
        puts "WAITING FOR #{domain} VALIDATION"

        raise VerificationTimeoutError if attempts == 60
        raise NotAuthorizedYetError if challenge.verify_status != 'valid'
      rescue NotAuthorizedYetError
        sleep 20
        attempts += 1
        retry
      ensure
        clean_wellknown_turds site
      end
      puts "DONE!"
    end

    csr = Acme::Client::CertificateRequest.new names: domains
    certificate = letsencrypt.new_certificate csr
    site.ssl_key = certificate.request.private_key.to_pem
    site.ssl_cert = certificate.fullchain_to_pem
    site.save_changes validate: false
    clean_wellknown_turds site

    # Refresh the cert periodically, current expire time is 90 days
    LetsEncryptWorker.perform_in 60.days, site.id
  end

  def clean_wellknown_turds(site)
    wellknown_path = File.join(site.base_files_path, '.well-known')

    if File.exist?(wellknown_path)
      FileUtils.rm_rf wellknown_path
    end
  end
end