require 'pg'

require 'common/davical_plugin'
require 'rm/rm_plugin'

# Handle the removal of DAViCal users from its database. DAViCal has
# no concept of domains.
#
class DavicalRm

  include DavicalPlugin
  include RmPlugin


  # Remove *user* from the DAViCal database. This should remove him
  # from _every_ table in which he is referenced. Fortunately, DAViCal
  # uses foreign keys properly (and only supports postgres, where they
  # work!), so we can let the ON DELETE CASCADE trigger handle most of
  # the work.
  #
  # @param user [User] the user to remove.
  #
  def remove_user(user)
    raise NonexistentUserError.new(user.to_s()) if not user_exists(user)

    sql_queries = ['DELETE FROM usr WHERE username = $1']

    connection = PGconn.connect(@db_host, @db_port, @db_opts, @db_tty,
                                @db_name, @db_user, @db_pass)

    sql_queries.each do |sql_query|
      connection.query(sql_query, [user.to_s()])
    end

    connection.close()
  end


end