class Arcanist

# File lib/arcanist.rb, line 9
  def diff work_dir, callsign, commit: 'HEAD^', differential_id: nil, message: nil, reviewers: ''
    arcrc = write_arcrc
    temps = [arcrc]
    args = ['--no-ansi', '--conduit-uri', conduit_uri, '--config', "repository.callsign=#{callsign}", '--arcrc-file', arcrc.path]

    if differential_id
      # update existing diff
      args += ['--update', differential_id.to_s, '--message', message || 'Update']
    else
      # create new diff
      tmp = Tempfile.create 'arcmsg'
      tmp.write <<"EOS"
#{message || Git::message(work_dir)}

Test Plan:
N/A (imported by gerricator)

Reviewers: #{[*reviewers].join(', ')}
EOS
      tmp.flush
      temps << tmp
      args += ['--create', '--message-file', tmp.path]
    end

    Dir.chdir work_dir do
      cmd = Shellwords.join(['arc', 'diff', *args, commit])
      result = `#{cmd}`

      if not differential_id
        differential_id = result[/#{File.join(conduit_uri, 'D')}(\d+)/, 1]
      end
    end

    differential_id
  ensure
    temps.each do |t|
      File.unlink(t) if t && File.exists?(t)
    end
  end

# File lib/arcanist.rb, line 51
def write_arcrc
  Tempfile.create('arcrc').tap do |t|
    content = {
      hosts: {
        File.join(conduit_uri, 'api/') => {
          user: user,
          cert: cert,
        }
      }
    }
    t.write JSON.dump(content)
    t.flush
  end
end