require 'fileutils'

require 'common/filesystem'
require 'common/dovecot_plugin'
require 'mv/mv_plugin'

class DovecotMv

  include DovecotPlugin
  include MvPlugin

  def mv_user(src, dst)
    # It's obviously an error if the source user does not exist.
    raise NonexistentUserError.new(src.to_s()) if not user_exists(src)

    # And it's an error if the destination user exists already.
    raise UserAlreadyExistsError.new(dst.to_s()) if user_exists(dst)

    # But is it an error if the target domain does not exist? That's a
    # bit subtle... The domain may exist in the database, but if it
    # has not received any mail yet, then its directory won't exist
    # on-disk.
    #
    # There are two possible "oops" scenarios resulting from the fact
    # that we may run either the Postfixadmin move first or the
    # Dovecot move first. If we move the user in the database, we
    # definitely want to move him on disk (that is, we should create
    # the directory here). But if we move him on disk first, then we
    # don't know if the database move will fail! We don't want to move
    # his mail files if he won't get moved in the database.
    #
    # Faced with two equally-bad (but easy-to-fix) options, we do the
    # simplest thing and fail if the destination domain directory
    # doesn't exist. If nothing else, this is at least consistent.
    if not self.domain_exists(dst.domain()) then
      raise NonexistentDomainError.new(dst.domainpart())
    end

    # We may need to create the target domain directory, even if the
    # domain exists in the database.
    FileUtils.mkdir_p(self.get_domain_path(dst.domain()))

    # The parent of dst_path exists because we just created it.The
    # source path should exist too, because the "source user" does,
    # and, well, how did we determine that?
    src_path = self.get_user_path(src)
    dst_path = self.get_user_path(dst)
    FileUtils.mv(src_path, dst_path)
  end

end