text: """IMAP4 client.
  
  Based on RFC 2060.
  
  Public class:           IMAP4
  Public variable:        Debug
  Public functions:       Internaldate2tuple
                          Int2AP
                          ParseFlags
                          Time2Internaldate
  """
  
  # Author: Piers Lauder <piers@cs.su.oz.au> December 1997.
  #
  # Authentication code contributed by Donn Cave <donn@u.washington.edu> June 1998.
  # String method conversion by ESR, February 2001.
  # GET/SETACL contributed by Anthony Baxter <anthony@interlink.com.au> April 2001.
  
  __version__ = "2.49"
  
  import binascii, re, socket, time, random, sys
  
  __all__ = ["IMAP4", "Internaldate2tuple",
             "Int2AP", "ParseFlags", "Time2Internaldate"]
  
  #       Globals
  
  CRLF = '\r\n'
  Debug = 0
  IMAP4_PORT = 143
  AllowedVersions = ('IMAP4REV1', 'IMAP4')        # Most recent first
  
  #       Commands
  
  Commands = {
          # name            valid states
          'APPEND':       ('AUTH', 'SELECTED'),
          'AUTHENTICATE': ('NONAUTH',),
          'CAPABILITY':   ('NONAUTH', 'AUTH', 'SELECTED', 'LOGOUT'),
          'CHECK':        ('SELECTED',),
          'CLOSE':        ('SELECTED',),
          'COPY':         ('SELECTED',),
          'CREATE':       ('AUTH', 'SELECTED'),
          'DELETE':       ('AUTH', 'SELECTED'),
          'EXAMINE':      ('AUTH', 'SELECTED'),
          'EXPUNGE':      ('SELECTED',),
          'FETCH':        ('SELECTED',),
          'GETACL':       ('AUTH', 'SELECTED'),
          'LIST':         ('AUTH', 'SELECTED'),
          'LOGIN':        ('NONAUTH',),
          'LOGOUT':       ('NONAUTH', 'AUTH', 'SELECTED', 'LOGOUT'),
          'LSUB':         ('AUTH', 'SELECTED'),
          'NAMESPACE':    ('AUTH', 'SELECTED'),
          'NOOP':         ('NONAUTH', 'AUTH', 'SELECTED', 'LOGOUT'),
          'PARTIAL':      ('SELECTED',),
          'RENAME':       ('AUTH', 'SELECTED'),
          'SEARCH':       ('SELECTED',),
          'SELECT':       ('AUTH', 'SELECTED'),
          'SETACL':       ('AUTH', 'SELECTED'),
          'SORT':         ('SELECTED',),
          'STATUS':       ('AUTH', 'SELECTED'),
          'STORE':        ('SELECTED',),
          'SUBSCRIBE':    ('AUTH', 'SELECTED'),
          'UID':          ('SELECTED',),
          'UNSUBSCRIBE':  ('AUTH', 'SELECTED'),
          }
  
  #       Patterns to match server responses
  
  Continuation = re.compile(r'\+( (?P<data>.*))?')
  Flags = re.compile(r'.*FLAGS \((?P<flags>[^\)]*)\)')
  InternalDate = re.compile(r'.*INTERNALDATE "'
          r'(?P<day>[ 123][0-9])-(?P<mon>[A-Z][a-z][a-z])-(?P<year>[0-9][0-9][0-9][0-9])'
          r' (?P<hour>[0-9][0-9]):(?P<min>[0-9][0-9]):(?P<sec>[0-9][0-9])'
          r' (?P<zonen>[-+])(?P<zoneh>[0-9][0-9])(?P<zonem>[0-9][0-9])'
          r'"')
  Literal = re.compile(r'.*{(?P<size>\d+)}$')
  Response_code = re.compile(r'\[(?P<type>[A-Z-]+)( (?P<data>[^\]]*))?\]')
  Untagged_response = re.compile(r'\* (?P<type>[A-Z-]+)( (?P<data>.*))?')
  Untagged_status = re.compile(r'\* (?P<data>\d+) (?P<type>[A-Z-]+)( (?P<data2>.*))?')
  
  
  
  class IMAP4:
  
      """IMAP4 client class.
  
      Instantiate with: IMAP4([host[, port]])
  
              host - host's name (default: localhost);
              port - port number (default: standard IMAP4 port).
  
      All IMAP4rev1 commands are supported by methods of the same
      name (in lower-case).
  
      All arguments to commands are converted to strings, except for
      AUTHENTICATE, and the last argument to APPEND which is passed as
      an IMAP4 literal.  If necessary (the string contains any
      non-printing characters or white-space and isn't enclosed with
      either parentheses or double quotes) each string is quoted.
      However, the 'password' argument to the LOGIN command is always
      quoted.  If you want to avoid having an argument string quoted
      (eg: the 'flags' argument to STORE) then enclose the string in
      parentheses (eg: "(\Deleted)").
  
      Each command returns a tuple: (type, [data, ...]) where 'type'
      is usually 'OK' or 'NO', and 'data' is either the text from the
      tagged response, or untagged results from command.
  
      Errors raise the exception class <instance>.error("<reason>").
      IMAP4 server errors raise <instance>.abort("<reason>"),
      which is a sub-class of 'error'. Mailbox status changes
      from READ-WRITE to READ-ONLY raise the exception class
      <instance>.readonly("<reason>"), which is a sub-class of 'abort'.
  
      "error" exceptions imply a program error.
      "abort" exceptions imply the connection should be reset, and
              the command re-tried.
      "readonly" exceptions imply the command should be re-tried.
  
      Note: to use this module, you must read the RFCs pertaining
      to the IMAP4 protocol, as the semantics of the arguments to
      each IMAP4 command are left to the invoker, not to mention
      the results.
      """
  
      class error(Exception): pass    # Logical errors - debug required
      class abort(error): pass        # Service errors - close and retry
      class readonly(abort): pass     # Mailbox status changed to READ-ONLY
  
      mustquote = re.compile(r"[^\w!#$%&'*+,.:;<=>?^`|~-]")
  
      def __init__(self, host = '', port = IMAP4_PORT):
          self.host = host
          self.port = port
          self.debug = Debug
          self.state = 'LOGOUT'
          self.literal = None             # A literal argument to a command
          self.tagged_commands = {}       # Tagged commands awaiting response
          self.untagged_responses = {}    # {typ: [data, ...], ...}
          self.continuation_response = '' # Last continuation response
          self.is_readonly = None         # READ-ONLY desired state
          self.tagnum = 0
  
          # Open socket to server.
  
          self.open(host, port)
  
          # Create unique tag for this session,
          # and compile tagged response matcher.
  
          self.tagpre = Int2AP(random.randint(0, 31999))
          self.tagre = re.compile(r'(?P<tag>'
                          + self.tagpre
                          + r'\d+) (?P<type>[A-Z]+) (?P<data>.*)')
  
          # Get server welcome message,
          # request and store CAPABILITY response.
  
          if __debug__:
              if self.debug >= 1:
                  _mesg('imaplib version %s' % __version__)
                  _mesg('new IMAP4 connection, tag=%s' % self.tagpre)
  
          self.welcome = self._get_response()
          if self.untagged_responses.has_key('PREAUTH'):
              self.state = 'AUTH'
          elif self.untagged_responses.has_key('OK'):
              self.state = 'NONAUTH'
          else:
              raise self.error(self.welcome)
  
          cap = 'CAPABILITY'
          self._simple_command(cap)
          if not self.untagged_responses.has_key(cap):
              raise self.error('no CAPABILITY response from server')
          self.capabilities = tuple(self.untagged_responses[cap][-1].upper().split())
  
          if __debug__:
              if self.debug >= 3:
                  _mesg('CAPABILITIES: %s' % `self.capabilities`)
  
          for version in AllowedVersions:
              if not version in self.capabilities:
                  continue
              self.PROTOCOL_VERSION = version
              return
  
          raise self.error('server not IMAP4 compliant')
  
  
      def __getattr__(self, attr):
          #       Allow UPPERCASE variants of IMAP4 command methods.
          if Commands.has_key(attr):
              return getattr(self, attr.lower())
          raise AttributeError("Unknown IMAP4 command: '%s'" % attr)
  
  
  
      #       Overridable methods
  
  
      def open(self, host, port):
          """Setup connection to remote server on "host:port".
          This connection will be used by the routines:
              read, readline, send, shutdown.
          """
          self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
          self.sock.connect((self.host, self.port))
          self.file = self.sock.makefile('rb')
  
  
      def read(self, size):
          """Read 'size' bytes from remote."""
          return self.file.read(size)
  
  
      def readline(self):
          """Read line from remote."""
          return self.file.readline()
  
  
      def send(self, data):
          """Send data to remote."""
          self.sock.sendall(data)
  
      def shutdown(self):
          """Close I/O established in "open"."""
          self.file.close()
          self.sock.close()
  
  
      def socket(self):
          """Return socket instance used to connect to IMAP4 server.
  
          socket = <instance>.socket()
          """
          return self.sock
  
  
  
      #       Utility methods
  
  
      def recent(self):
          """Return most recent 'RECENT' responses if any exist,
          else prompt server for an update using the 'NOOP' command.
  
          (typ, [data]) = <instance>.recent()
  
          'data' is None if no new messages,
          else list of RECENT responses, most recent last.
          """
          name = 'RECENT'
          typ, dat = self._untagged_response('OK', [None], name)
          if dat[-1]:
              return typ, dat
          typ, dat = self.noop()  # Prod server for response
          return self._untagged_response(typ, dat, name)
  
  
      def response(self, code):
          """Return data for response 'code' if received, or None.
  
          Old value for response 'code' is cleared.
  
          (code, [data]) = <instance>.response(code)
          """
          return self._untagged_response(code, [None], code.upper())
  
  
  
      #       IMAP4 commands
  
  
      def append(self, mailbox, flags, date_time, message):
          """Append message to named mailbox.
  
          (typ, [data]) = <instance>.append(mailbox, flags, date_time, message)
  
                  All args except `message' can be None.
          """
          name = 'APPEND'
          if not mailbox:
              mailbox = 'INBOX'
          if flags:
              if (flags[0],flags[-1]) != ('(',')'):
                  flags = '(%s)' % flags
          else:
              flags = None
          if date_time:
              date_time = Time2Internaldate(date_time)
          else:
              date_time = None
          self.literal = message
          return self._simple_command(name, mailbox, flags, date_time)
  
  
      def authenticate(self, mechanism, authobject):
          """Authenticate command - requires response processing.
  
          'mechanism' specifies which authentication mechanism is to
          be used - it must appear in <instance>.capabilities in the
          form AUTH=<mechanism>.
  
          'authobject' must be a callable object:
  
                  data = authobject(response)
  
          It will be called to process server continuation responses.
          It should return data that will be encoded and sent to server.
          It should return None if the client abort response '*' should
          be sent instead.
          """
          mech = mechanism.upper()
          cap = 'AUTH=%s' % mech
          if not cap in self.capabilities:
              raise self.error("Server doesn't allow %s authentication." % mech)
          self.literal = _Authenticator(authobject).process
          typ, dat = self._simple_command('AUTHENTICATE', mech)
          if typ != 'OK':
              raise self.error(dat[-1])
          self.state = 'AUTH'
          return typ, dat
  
  
      def check(self):
          """Checkpoint mailbox on server.
  
          (typ, [data]) = <instance>.check()
          """
          return self._simple_command('CHECK')
  
  
      def close(self):
          """Close currently selected mailbox.
  
          Deleted messages are removed from writable mailbox.
          This is the recommended command before 'LOGOUT'.
  
          (typ, [data]) = <instance>.close()
          """
          try:
              typ, dat = self._simple_command('CLOSE')
          finally:
              self.state = 'AUTH'
          return typ, dat
  
  
      def copy(self, message_set, new_mailbox):
          """Copy 'message_set' messages onto end of 'new_mailbox'.
  
          (typ, [data]) = <instance>.copy(message_set, new_mailbox)
          """
          return self._simple_command('COPY', message_set, new_mailbox)
  
  
      def create(self, mailbox):
          """Create new mailbox.
  
          (typ, [data]) = <instance>.create(mailbox)
          """
          return self._simple_command('CREATE', mailbox)
  
  
      def delete(self, mailbox):
          """Delete old mailbox.
  
          (typ, [data]) = <instance>.delete(mailbox)
          """
          return self._simple_command('DELETE', mailbox)
  
  
      def expunge(self):
          """Permanently remove deleted items from selected mailbox.
  
          Generates 'EXPUNGE' response for each deleted message.
  
          (typ, [data]) = <instance>.expunge()
  
          'data' is list of 'EXPUNGE'd message numbers in order received.
          """
          name = 'EXPUNGE'
          typ, dat = self._simple_command(name)
          return self._untagged_response(typ, dat, name)
  
  
      def fetch(self, message_set, message_parts):
          """Fetch (parts of) messages.
  
          (typ, [data, ...]) = <instance>.fetch(message_set, message_parts)
  
          'message_parts' should be a string of selected parts
          enclosed in parentheses, eg: "(UID BODY[TEXT])".
  
          'data' are tuples of message part envelope and data.
          """
          name = 'FETCH'
          typ, dat = self._simple_command(name, message_set, message_parts)
          return self._untagged_response(typ, dat, name)
  
  
      def getacl(self, mailbox):
          """Get the ACLs for a mailbox.
  
          (typ, [data]) = <instance>.getacl(mailbox)
          """
          typ, dat = self._simple_command('GETACL', mailbox)
          return self._untagged_response(typ, dat, 'ACL')
  
  
      def list(self, directory='""', pattern='*'):
          """List mailbox names in directory matching pattern.
  
          (typ, [data]) = <instance>.list(directory='""', pattern='*')
  
          'data' is list of LIST responses.
          """
          name = 'LIST'
          typ, dat = self._simple_command(name, directory, pattern)
          return self._untagged_response(typ, dat, name)
  
  
      def login(self, user, password):
          """Identify client using plaintext password.
  
          (typ, [data]) = <instance>.login(user, password)
  
          NB: 'password' will be quoted.
          """
          #if not 'AUTH=LOGIN' in self.capabilities:
          #       raise self.error("Server doesn't allow LOGIN authentication." % mech)
          typ, dat = self._simple_command('LOGIN', user, self._quote(password))
          if typ != 'OK':
              raise self.error(dat[-1])
          self.state = 'AUTH'
          return typ, dat
  
  
      def logout(self):
          """Shutdown connection to server.
  
          (typ, [data]) = <instance>.logout()
  
          Returns server 'BYE' response.
          """
          self.state = 'LOGOUT'
          try: typ, dat = self._simple_command('LOGOUT')
          except: typ, dat = 'NO', ['%s: %s' % sys.exc_info()[:2]]
          self.shutdown()
          if self.untagged_responses.has_key('BYE'):
              return 'BYE', self.untagged_responses['BYE']
          return typ, dat
  
  
      def lsub(self, directory='""', pattern='*'):
          """List 'subscribed' mailbox names in directory matching pattern.
  
          (typ, [data, ...]) = <instance>.lsub(directory='""', pattern='*')
  
          'data' are tuples of message part envelope and data.
          """
          name = 'LSUB'
          typ, dat = self._simple_command(name, directory, pattern)
          return self._untagged_response(typ, dat, name)
  
  
      def namespace(self):
          """ Returns IMAP namespaces ala rfc2342
  
          (typ, [data, ...]) = <instance>.namespace()
          """
          name = 'NAMESPACE'
          typ, dat = self._simple_command(name)
          return self._untagged_response(typ, dat, name)
  
  
      def noop(self):
          """Send NOOP command.
  
          (typ, data) = <instance>.noop()
          """
          if __debug__:
              if self.debug >= 3:
                  _dump_ur(self.untagged_responses)
          return self._simple_command('NOOP')
  
  
      def partial(self, message_num, message_part, start, length):
          """Fetch truncated part of a message.
  
          (typ, [data, ...]) = <instance>.partial(message_num, message_part, start, length)
  
          'data' is tuple of message part envelope and data.
          """
          name = 'PARTIAL'
          typ, dat = self._simple_command(name, message_num, message_part, start, length)
          return self._untagged_response(typ, dat, 'FETCH')
  
  
      def rename(self, oldmailbox, newmailbox):
          """Rename old mailbox name to new.
  
          (typ, data) = <instance>.rename(oldmailbox, newmailbox)
          """
          return self._simple_command('RENAME', oldmailbox, newmailbox)
  
  
      def search(self, charset, *criteria):
          """Search mailbox for matching messages.
  
          (typ, [data]) = <instance>.search(charset, criterium, ...)
  
          'data' is space separated list of matching message numbers.
          """
          name = 'SEARCH'
          if charset:
              typ, dat = apply(self._simple_command, (name, 'CHARSET', charset) + criteria)
          else:
              typ, dat = apply(self._simple_command, (name,) + criteria)
          return self._untagged_response(typ, dat, name)
  
  
      def select(self, mailbox='INBOX', readonly=None):
          """Select a mailbox.
  
          Flush all untagged responses.
  
          (typ, [data]) = <instance>.select(mailbox='INBOX', readonly=None)
  
          'data' is count of messages in mailbox ('EXISTS' response).
          """
          # Mandated responses are ('FLAGS', 'EXISTS', 'RECENT', 'UIDVALIDITY')
          self.untagged_responses = {}    # Flush old responses.
          self.is_readonly = readonly
          if readonly:
              name = 'EXAMINE'
          else:
              name = 'SELECT'
          typ, dat = self._simple_command(name, mailbox)
          if typ != 'OK':
              self.state = 'AUTH'     # Might have been 'SELECTED'
              return typ, dat
          self.state = 'SELECTED'
          if self.untagged_responses.has_key('READ-ONLY') \
                  and not readonly:
              if __debug__:
                  if self.debug >= 1:
                      _dump_ur(self.untagged_responses)
              raise self.readonly('%s is not writable' % mailbox)
          return typ, self.untagged_responses.get('EXISTS', [None])
  
  
      def setacl(self, mailbox, who, what):
          """Set a mailbox acl.
  
          (typ, [data]) = <instance>.create(mailbox, who, what)
          """
          return self._simple_command('SETACL', mailbox, who, what)
  
  
      def sort(self, sort_criteria, charset, *search_criteria):
          """IMAP4rev1 extension SORT command.
  
          (typ, [data]) = <instance>.sort(sort_criteria, charset, search_criteria, ...)
          """
          name = 'SORT'
          #if not name in self.capabilities:      # Let the server decide!
          #       raise self.error('unimplemented extension command: %s' % name)
          if (sort_criteria[0],sort_criteria[-1]) != ('(',')'):
              sort_criteria = '(%s)' % sort_criteria
          typ, dat = apply(self._simple_command, (name, sort_criteria, charset) + search_criteria)
          return self._untagged_response(typ, dat, name)
  
  
      def status(self, mailbox, names):
          """Request named status conditions for mailbox.
  
          (typ, [data]) = <instance>.status(mailbox, names)
          """
          name = 'STATUS'
          #if self.PROTOCOL_VERSION == 'IMAP4':   # Let the server decide!
          #    raise self.error('%s unimplemented in IMAP4 (obtain IMAP4rev1 server, or re-code)' % name)
          typ, dat = self._simple_command(name, mailbox, names)
          return self._untagged_response(typ, dat, name)
  
  
      def store(self, message_set, command, flags):
          """Alters flag dispositions for messages in mailbox.
  
          (typ, [data]) = <instance>.store(message_set, command, flags)
          """
          if (flags[0],flags[-1]) != ('(',')'):
              flags = '(%s)' % flags  # Avoid quoting the flags
          typ, dat = self._simple_command('STORE', message_set, command, flags)
          return self._untagged_response(typ, dat, 'FETCH')
  
  
      def subscribe(self, mailbox):
          """Subscribe to new mailbox.
  
          (typ, [data]) = <instance>.subscribe(mailbox)
          """
          return self._simple_command('SUBSCRIBE', mailbox)
  
  
      def uid(self, command, *args):
          """Execute "command arg ..." with messages identified by UID,
                  rather than message number.
  
          (typ, [data]) = <instance>.uid(command, arg1, arg2, ...)
  
          Returns response appropriate to 'command'.
          """
          command = command.upper()
          if not Commands.has_key(command):
              raise self.error("Unknown IMAP4 UID command: %s" % command)
          if self.state not in Commands[command]:
              raise self.error('command %s illegal in state %s'
                                      % (command, self.state))
          name = 'UID'
          typ, dat = apply(self._simple_command, (name, command) + args)
          if command in ('SEARCH', 'SORT'):
              name = command
          else:
              name = 'FETCH'
          return self._untagged_response(typ, dat, name)
  
  
      def unsubscribe(self, mailbox):
          """Unsubscribe from old mailbox.
  
          (typ, [data]) = <instance>.unsubscribe(mailbox)
          """
          return self._simple_command('UNSUBSCRIBE', mailbox)
  
  
      def xatom(self, name, *args):
          """Allow simple extension commands
                  notified by server in CAPABILITY response.
  
          Assumes command is legal in current state.
  
          (typ, [data]) = <instance>.xatom(name, arg, ...)
  
          Returns response appropriate to extension command `name'.
          """
          name = name.upper()
          #if not name in self.capabilities:      # Let the server decide!
          #    raise self.error('unknown extension command: %s' % name)
          if not Commands.has_key(name):
              Commands[name] = (self.state,)
          return apply(self._simple_command, (name,) + args)
  
  
  
      #       Private methods
  
  
      def _append_untagged(self, typ, dat):
  
          if dat is None: dat = ''
          ur = self.untagged_responses
          if __debug__:
              if self.debug >= 5:
                  _mesg('untagged_responses[%s] %s += ["%s"]' %
                          (typ, len(ur.get(typ,'')), dat))
          if ur.has_key(typ):
              ur[typ].append(dat)
          else:
              ur[typ] = [dat]
  
  
      def _check_bye(self):
          bye = self.untagged_responses.get('BYE')
          if bye:
              raise self.abort(bye[-1])
  
  
      def _command(self, name, *args):
  
          if self.state not in Commands[name]:
              self.literal = None
              raise self.error(
              'command %s illegal in state %s' % (name, self.state))
  
          for typ in ('OK', 'NO', 'BAD'):
              if self.untagged_responses.has_key(typ):
                  del self.untagged_responses[typ]
  
          if self.untagged_responses.has_key('READ-ONLY') \
          and not self.is_readonly:
              raise self.readonly('mailbox status changed to READ-ONLY')
  
          tag = self._new_tag()
          data = '%s %s' % (tag, name)
          for arg in args:
              if arg is None: continue
              data = '%s %s' % (data, self._checkquote(arg))
  
          literal = self.literal
          if literal is not None:
              self.literal = None
              if type(literal) is type(self._command):
                  literator = literal
              else:
                  literator = None
                  data = '%s {%s}' % (data, len(literal))
  
          if __debug__:
              if self.debug >= 4:
                  _mesg('> %s' % data)
              else:
                  _log('> %s' % data)
  
          try:
              self.send('%s%s' % (data, CRLF))
          except (socket.error, OSError), val:
              raise self.abort('socket error: %s' % val)
  
          if literal is None:
              return tag
  
          while 1:
              # Wait for continuation response
  
              while self._get_response():
                  if self.tagged_commands[tag]:   # BAD/NO?
                      return tag
  
              # Send literal
  
              if literator:
                  literal = literator(self.continuation_response)
  
              if __debug__:
                  if self.debug >= 4:
                      _mesg('write literal size %s' % len(literal))
  
              try:
                  self.send(literal)
                  self.send(CRLF)
              except (socket.error, OSError), val:
                  raise self.abort('socket error: %s' % val)
  
              if not literator:
                  break
  
          return tag
  
  
      def _command_complete(self, name, tag):
          self._check_bye()
          try:
              typ, data = self._get_tagged_response(tag)
          except self.abort, val:
              raise self.abort('command: %s => %s' % (name, val))
          except self.error, val:
              raise self.error('command: %s => %s' % (name, val))
          self._check_bye()
          if typ == 'BAD':
              raise self.error('%s command error: %s %s' % (name, typ, data))
          return typ, data
  
  
      def _get_response(self):
  
          # Read response and store.
          #
          # Returns None for continuation responses,
          # otherwise first response line received.
  
          resp = self._get_line()
  
          # Command completion response?
  
          if self._match(self.tagre, resp):
              tag = self.mo.group('tag')
              if not self.tagged_commands.has_key(tag):
                  raise self.abort('unexpected tagged response: %s' % resp)
  
              typ = self.mo.group('type')
              dat = self.mo.group('data')
              self.tagged_commands[tag] = (typ, [dat])
          else:
              dat2 = None
  
              # '*' (untagged) responses?
  
              if not self._match(Untagged_response, resp):
                  if self._match(Untagged_status, resp):
                      dat2 = self.mo.group('data2')
  
              if self.mo is None:
                  # Only other possibility is '+' (continuation) response...
  
                  if self._match(Continuation, resp):
                      self.continuation_response = self.mo.group('data')
                      return None     # NB: indicates continuation
  
                  raise self.abort("unexpected response: '%s'" % resp)
  
              typ = self.mo.group('type')
              dat = self.mo.group('data')
              if dat is None: dat = ''        # Null untagged response
              if dat2: dat = dat + ' ' + dat2
  
              # Is there a literal to come?
  
              while self._match(Literal, dat):
  
                  # Read literal direct from connection.
  
                  size = int(self.mo.group('size'))
                  if __debug__:
                      if self.debug >= 4:
                          _mesg('read literal size %s' % size)
                  data = self.read(size)
  
                  # Store response with literal as tuple
  
                  self._append_untagged(typ, (dat, data))
  
                  # Read trailer - possibly containing another literal
  
                  dat = self._get_line()
  
              self._append_untagged(typ, dat)
  
          # Bracketed response information?
  
          if typ in ('OK', 'NO', 'BAD') and self._match(Response_code, dat):
              self._append_untagged(self.mo.group('type'), self.mo.group('data'))
  
          if __debug__:
              if self.debug >= 1 and typ in ('NO', 'BAD', 'BYE'):
                  _mesg('%s response: %s' % (typ, dat))
  
          return resp
  
  
      def _get_tagged_response(self, tag):
  
          while 1:
              result = self.tagged_commands[tag]
              if result is not None:
                  del self.tagged_commands[tag]
                  return result
  
              # Some have reported "unexpected response" exceptions.
              # Note that ignoring them here causes loops.
              # Instead, send me details of the unexpected response and
              # I'll update the code in `_get_response()'.
  
              try:
                  self._get_response()
              except self.abort, val:
                  if __debug__:
                      if self.debug >= 1:
                          print_log()
                  raise
  
  
      def _get_line(self):
  
          line = self.readline()
          if not line:
              raise self.abort('socket error: EOF')
  
          # Protocol mandates all lines terminated by CRLF
  
          line = line[:-2]
          if __debug__:
              if self.debug >= 4:
                  _mesg('< %s' % line)
              else:
                  _log('< %s' % line)
          return line
  
  
      def _match(self, cre, s):
  
          # Run compiled regular expression match method on 's'.
          # Save result, return success.
  
          self.mo = cre.match(s)
          if __debug__:
              if self.mo is not None and self.debug >= 5:
                  _mesg("\tmatched r'%s' => %s" % (cre.pattern, `self.mo.groups()`))
          return self.mo is not None
  
  
      def _new_tag(self):
  
          tag = '%s%s' % (self.tagpre, self.tagnum)
          self.tagnum = self.tagnum + 1
          self.tagged_commands[tag] = None
          return tag
  
  
      def _checkquote(self, arg):
  
          # Must quote command args if non-alphanumeric chars present,
          # and not already quoted.
  
          if type(arg) is not type(''):
              return arg
          if (arg[0],arg[-1]) in (('(',')'),('"','"')):
              return arg
          if self.mustquote.search(arg) is None:
              return arg
          return self._quote(arg)
  
  
      def _quote(self, arg):
  
          arg = arg.replace('\\', '\\\\')
          arg = arg.replace('"', '\\"')
  
          return '"%s"' % arg
  
  
      def _simple_command(self, name, *args):
  
          return self._command_complete(name, apply(self._command, (name,) + args))
  
  
      def _untagged_response(self, typ, dat, name):
  
          if typ == 'NO':
              return typ, dat
          if not self.untagged_responses.has_key(name):
              return typ, [None]
          data = self.untagged_responses[name]
          if __debug__:
              if self.debug >= 5:
                  _mesg('untagged_responses[%s] => %s' % (name, data))
          del self.untagged_responses[name]
          return typ, data
  
  
  
  class _Authenticator:
  
      """Private class to provide en/decoding
              for base64-based authentication conversation.
      """
  
      def __init__(self, mechinst):
          self.mech = mechinst    # Callable object to provide/process data
  
      def process(self, data):
          ret = self.mech(self.decode(data))
          if ret is None:
              return '*'      # Abort conversation
          return self.encode(ret)
  
      def encode(self, inp):
          #
          #  Invoke binascii.b2a_base64 iteratively with
          #  short even length buffers, strip the trailing
          #  line feed from the result and append.  "Even"
          #  means a number that factors to both 6 and 8,
          #  so when it gets to the end of the 8-bit input
          #  there's no partial 6-bit output.
          #
          oup = ''
          while inp:
              if len(inp) > 48:
                  t = inp[:48]
                  inp = inp[48:]
              else:
                  t = inp
                  inp = ''
              e = binascii.b2a_base64(t)
              if e:
                  oup = oup + e[:-1]
          return oup
  
      def decode(self, inp):
          if not inp:
              return ''
          return binascii.a2b_base64(inp)
  
  
  
  Mon2num = {'Jan': 1, 'Feb': 2, 'Mar': 3, 'Apr': 4, 'May': 5, 'Jun': 6,
          'Jul': 7, 'Aug': 8, 'Sep': 9, 'Oct': 10, 'Nov': 11, 'Dec': 12}
  
  def Internaldate2tuple(resp):
      """Convert IMAP4 INTERNALDATE to UT.
  
      Returns Python time module tuple.
      """
  
      mo = InternalDate.match(resp)
      if not mo:
          return None
  
      mon = Mon2num[mo.group('mon')]
      zonen = mo.group('zonen')
  
      day = int(mo.group('day'))
      year = int(mo.group('year'))
      hour = int(mo.group('hour'))
      min = int(mo.group('min'))
      sec = int(mo.group('sec'))
      zoneh = int(mo.group('zoneh'))
      zonem = int(mo.group('zonem'))
  
      # INTERNALDATE timezone must be subtracted to get UT
  
      zone = (zoneh*60 + zonem)*60
      if zonen == '-':
          zone = -zone
  
      tt = (year, mon, day, hour, min, sec, -1, -1, -1)
  
      utc = time.mktime(tt)
  
      # Following is necessary because the time module has no 'mkgmtime'.
      # 'mktime' assumes arg in local timezone, so adds timezone/altzone.
  
      lt = time.localtime(utc)
      if time.daylight and lt[-1]:
          zone = zone + time.altzone
      else:
          zone = zone + time.timezone
  
      return time.localtime(utc - zone)
  
  
  
  def Int2AP(num):
  
      """Convert integer to A-P string representation."""
  
      val = ''; AP = 'ABCDEFGHIJKLMNOP'
      num = int(abs(num))
      while num:
          num, mod = divmod(num, 16)
          val = AP[mod] + val
      return val
  
  
  
  def ParseFlags(resp):
  
      """Convert IMAP4 flags response to python tuple."""
  
      mo = Flags.match(resp)
      if not mo:
          return ()
  
      return tuple(mo.group('flags').split())
  
  
  def Time2Internaldate(date_time):
  
      """Convert 'date_time' to IMAP4 INTERNALDATE representation.
  
      Return string in form: '"DD-Mmm-YYYY HH:MM:SS +HHMM"'
      """
  
      if isinstance(date_time, (int, float)):
          tt = time.localtime(date_time)
      elif isinstance(date_time, (tuple, time.struct_time)):
          tt = date_time
      elif isinstance(date_time, str):
          return date_time        # Assume in correct format
      else:
          raise ValueError("date_time not of a known type")
  
      dt = time.strftime("%d-%b-%Y %H:%M:%S", tt)
      if dt[0] == '0':
          dt = ' ' + dt[1:]
      if time.daylight and tt[-1]:
          zone = -time.altzone
      else:
          zone = -time.timezone
      return '"' + dt + " %+03d%02d" % divmod(zone/60, 60) + '"'
  
  
  
  if __debug__:
  
      def _mesg(s, secs=None):
          if secs is None:
              secs = time.time()
          tm = time.strftime('%M:%S', time.localtime(secs))
          sys.stderr.write('  %s.%02d %s\n' % (tm, (secs*100)%100, s))
          sys.stderr.flush()
  
      def _dump_ur(dict):
          # Dump untagged responses (in `dict').
          l = dict.items()
          if not l: return
          t = '\n\t\t'
          l = map(lambda x:'%s: "%s"' % (x[0], x[1][0] and '" "'.join(x[1]) or ''), l)
          _mesg('untagged responses dump:%s%s' % (t, t.join(l)))
  
      _cmd_log = []           # Last `_cmd_log_len' interactions
      _cmd_log_len = 10
  
      def _log(line):
          # Keep log of last `_cmd_log_len' interactions for debugging.
          if len(_cmd_log) == _cmd_log_len:
              del _cmd_log[0]
          _cmd_log.append((time.time(), line))
  
      def print_log():
          _mesg('last %d IMAP4 interactions:' % len(_cmd_log))
          for secs,line in _cmd_log:
              _mesg(line, secs)
  
  
  
  if __name__ == '__main__':
  
      import getopt, getpass
  
      try:
          optlist, args = getopt.getopt(sys.argv[1:], 'd:')
      except getopt.error, val:
          pass
  
      for opt,val in optlist:
          if opt == '-d':
              Debug = int(val)
  
      if not args: args = ('',)
  
      host = args[0]
  
      USER = getpass.getuser()
      PASSWD = getpass.getpass("IMAP password for %s on %s: " % (USER, host or "localhost"))
  
      test_mesg = 'From: %(user)s@localhost%(lf)sSubject: IMAP4 test%(lf)s%(lf)sdata...%(lf)s' % {'user':USER, 'lf':CRLF}
      test_seq1 = (
      ('login', (USER, PASSWD)),
      ('create', ('/tmp/xxx 1',)),
      ('rename', ('/tmp/xxx 1', '/tmp/yyy')),
      ('CREATE', ('/tmp/yyz 2',)),
      ('append', ('/tmp/yyz 2', None, None, test_mesg)),
      ('list', ('/tmp', 'yy*')),
      ('select', ('/tmp/yyz 2',)),
      ('search', (None, 'SUBJECT', 'test')),
      ('partial', ('1', 'RFC822', 1, 1024)),
      ('store', ('1', 'FLAGS', '(\Deleted)')),
      ('namespace', ()),
      ('expunge', ()),
      ('recent', ()),
      ('close', ()),
      )
  
      test_seq2 = (
      ('select', ()),
      ('response',('UIDVALIDITY',)),
      ('uid', ('SEARCH', 'ALL')),
      ('response', ('EXISTS',)),
      ('append', (None, None, None, test_mesg)),
      ('recent', ()),
      ('logout', ()),
      )
  
      def run(cmd, args):
          _mesg('%s %s' % (cmd, args))
          typ, dat = apply(getattr(M, cmd), args)
          _mesg('%s => %s %s' % (cmd, typ, dat))
          return dat
  
      try:
          M = IMAP4(host)
          _mesg('PROTOCOL_VERSION = %s' % M.PROTOCOL_VERSION)
          _mesg('CAPABILITIES = %s' % `M.capabilities`)
  
          for cmd,args in test_seq1:
              run(cmd, args)
  
          for ml in run('list', ('/tmp/', 'yy%')):
              mo = re.match(r'.*"([^"]+)"$', ml)
              if mo: path = mo.group(1)
              else: path = ml.split()[-1]
              run('delete', (path,))
  
          for cmd,args in test_seq2:
              dat = run(cmd, args)
  
              if (cmd,args) != ('uid', ('SEARCH', 'ALL')):
                  continue
  
              uid = dat[-1].split()
              if not uid: continue
              run('uid', ('FETCH', '%s' % uid[-1],
                      '(FLAGS INTERNALDATE RFC822.SIZE RFC822.HEADER RFC822.TEXT)'))
  
          print '\nAll tests OK.'
  
      except:
          print '\nTests failed.'
  
          if not Debug:
              print '''
  If you would like to see debugging output,
  try: %s -d5
  ''' % sys.argv[0]
  
          raise
  