# Copyright (C) 1998 by the Free Software Foundation, Inc.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software 
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.


"""Process mailing list user commands arriving via email."""

# Try to stay close to majordomo commands, but accept common mistakes.
# Not implemented: get / index / which.

import os
import sys
import string
import re
import traceback
import Message
import Errors
import mm_cfg
import Utils
import MailList

try:
    from cStringIO import StringIO
except ImportError:
    from StringIO import StringIO


MAXERRORS = 5
MAXCOLUMN = 70

option_descs = {
    'hide'   :  '''When turned on, your email address is concealed
on the Web page that lists the members of the mailing list.''',
    'nomail' : '''When turned on, delivery to your email address is disabled,
but your address is still subscribed.  This is useful if you plan on 
taking a short vacation.''',
    'ack'    : '''When turned on, you get a separate acknowledgement email
when you post messages to the list.''',
    'notmetoo': '''When turned on, you do *not* get copies of your own
posts to the list.  Otherwise, you do get copies of your own posts
 (yes, this seems a little backwards).  This does not affect the contents
of digests, so if you receive postings in digests, you will always get
copies of your messages in the digest.''',
    'digest' : '''When turned on, you get postings from the list bundled
into digests.  Otherwise, you get each individual message immediately as
it is posted to the list.''',
    'plain'  : """When turned on, you get `plain' digests, which are actually
formatted using the older RFC934 digest format.  This format can be easier
to read if you have a non-MIME compliant mail reader.  When this option is
turned off, you get digests in MIME format, which are much better if you
have a mail reader that supports MIME.""",
    }

option_info = {'digest'  : 0,
               'nomail'  : mm_cfg.DisableDelivery,
               'notmetoo': mm_cfg.DontReceiveOwnPosts,
               'ack'     : mm_cfg.AcknowlegePosts,
               'plain'   : mm_cfg.DisableMime,
               'hide'    : mm_cfg.ConcealSubscription
               }

# ordered list
options = ('hide', 'nomail', 'ack', 'notmetoo', 'digest', 'plain')



class MailCommandHandler:
    def __init__(self):
        self.__errors = 0
	self.__respbuf = ''
	self.__dispatch = {
	    'subscribe'   : self.ProcessSubscribeCmd,
            'confirm'     : self.ProcessConfirmCmd,
	    'unsubscribe' : self.ProcessUnsubscribeCmd,
	    'who'         : self.ProcessWhoCmd,
	    'info'        : self.ProcessInfoCmd,
	    'lists'       : self.ProcessListsCmd,
	    'help'        : self.ProcessHelpCmd,
	    'set'         : self.ProcessSetCmd,
	    'options'     : self.ProcessOptionsCmd,
	    'password'    : self.ProcessPasswordCmd,
	    }
        self.__NoMailCmdResponse = 0

    def AddToResponse(self, text, trunc=MAXCOLUMN, prefix=""):
        # Strip final newline
        if text and text[-1] == '\n':
            text = text[:-1]
        for line in string.split(text, '\n'):
            line = prefix + line
            if trunc and len(line) > trunc:
                line = line[:trunc-3] + '...'
            self.__respbuf = self.__respbuf + line + "\n"

    def AddError(self, text, prefix='>>>>> ', trunc=MAXCOLUMN):
        self.__errors = self.__errors + 1
        self.AddToResponse(text, trunc=trunc, prefix=prefix)
	
    def ParseMailCommands(self):
	msg = Message.IncomingMessage()
	subject = msg.getheader("subject")
        sender = string.lower(msg.GetSender())
        sender = string.split(sender, "@")[0]
        #
        # XXX: why 'orphanage'?
        if sender in ['daemon', 'nobody', 'mailer-daemon', 'postmaster',
                      'orphanage', 'postoffice']:
            #
            # This is for what are probably delivery-failure notices of
            # subscription confirmations that are, of necessity, bounced
            # back to the -request address.
            self.LogMsg("bounce",
                        ("%s: Mailcmd rejected"
                         "\n\tReason: Probable bounced subscribe-confirmation"
                         "\n\tFrom: %s"
                         "\n\tSubject: %s"
                         ),
                        self._internal_name,
                        msg.getheader('from'),
                        subject)
            return
	if subject:
	    subject = string.strip(subject)
	if (subject and
            self.__dispatch.has_key(string.lower(string.split(subject)[0]))):
	    lines = [subject] + string.split(msg.body, '\n')
        else:
	    lines = string.split(msg.body, '\n')
	    if subject:
		#
		# check to see if confirmation request -- special handling
		conf_pat = (r'%s\s+--\s+confirmation\s+of\s+subscription'
                            r'\s+--\s+request\s+(\d{6})'
                            % re.escape(self.real_name))
		mo = re.search(conf_pat, subject, re.IGNORECASE)
		if not mo:
		    mo = re.search(conf_pat, msg.body)
		if mo:
		    lines = ["confirm %s" % (mo.group(1))]
		else:
		    self.AddError('Subject line ignored:\n  ' + subject)
        processed = {}                      # For avoiding redundancies.
        maxlines = mm_cfg.DEFAULT_MAIL_COMMANDS_MAX_LINES
	for linecount in range(len(lines)):
            if linecount > maxlines:
                self.AddError("Maximum command lines (%d) encountered,"
                              " ignoring the rest..." % maxlines)
                for line in lines[linecount:]:
                    self.AddToResponse("> " + line, trunc=0)
                break
	    line = string.strip(lines[linecount])
	    if not line:
		continue
	    args = string.split(line)
	    cmd = string.lower(args[0])
	    args = args[1:]
	    if cmd in ['end', '--']:
		self.AddToResponse('\n***** End: ' + line + '\n'
                                   'The rest of the message is ignored:')
                for line in lines[linecount+1:]:
                    self.AddToResponse(line, trunc=0, prefix='> ')
		break
	    if not self.__dispatch.has_key(cmd):
                self.AddError(line, prefix='Command? ')
                if self.__errors >= MAXERRORS:
                    self.AddError('\nToo many errors encountered; '
                                  'the rest of the message is ignored:')
                    for line in lines[linecount+1:]:
                        self.AddToResponse(line, trunc=0, prefix='> ')
                    break
	    else:
                # We do not repeat identical commands.  (Eg, it's common
                # with other mlm's for people to put a command in the
                # subject and the body, uncertain which one has effect...)
                isdup = 0
                if not processed.has_key(cmd):
                    processed[cmd] = []
                else:
                    for did in processed[cmd]:
                        if args == did:
                            isdup = 1
                            break
                if not isdup:
                    processed[cmd].append(args)
                    self.AddToResponse('\n***** ' + line)
                    try:
                        # note that all expected exceptions must be handled by 
                        # the dispatch function.  We'll globally collect any
                        # unexpected (e.g. uncaught) exceptions here.  Such an 
                        # exception stops parsing of email commands
                        # immediately
                        self.__dispatch[cmd](args, line, msg)
                    except:
                        admin = self.GetAdminEmail()
                        sfp = StringIO()
                        traceback.print_exc(file=sfp)
                        tbmsg = sfp.getvalue()
                        errmsg = Utils.wrap('''\
An unexpected Mailman error has occurred.

Please forward your request to the human list administrator in charge of this
list at <%s>.  The traceback is attached below and will be forwarded to the list
administrator automatically.''' % admin)
                        self.AddError(errmsg, trunc=0)
                        self.AddToResponse('\n' + tbmsg, trunc=0)
                        # log it to the error file
                        self.LogMsg('error',
                                    'Unexpected Mailman error:\n%s' % tbmsg)
                        # and send the traceback to the user
                        self.SendTextToUser(subject='Unexpected Mailman error',
                                            recipient=admin,
                                            text='''\
An unexpected Mailman error has occurred in
MailCommandHandler.ParseMailCommands().  Here is the traceback:

''' + tbmsg,
                                            add_headers=['Errors-To: %s' %
                                                         admin,
                                                         'X-No-Archive: yes',
                                                         'Precedence: bulk'])
                        break
        # send the response
        if not self.__NoMailCmdResponse:
            if self.__errors > 0:
                header = Utils.wrap('''This is an automated response.

There were problems with the email commands you sent to Mailman via
the administrative address <%(sender)s>.

To obtain instructions on valid Mailman email commands, send email to
<%(sender)s> with the word "help" in the subject line or in the body
of the message.

If you want to reach the human being that manages this mailing list,
please send your message to <%(admin)s>.

The following is a detailed description of the problems.

''' % {'sender': self.GetRequestEmail(),
       'admin' : self.GetAdminEmail(),
       })
                self.__respbuf = header + self.__respbuf
            self.SendMailCmdResponse(msg)

    def SendMailCmdResponse(self, mail):
        subject = 'Mailman results for %s' % self.real_name
	self.SendTextToUser(subject   = subject,
			    recipient = mail.GetSender(),
			    sender    = self.GetRequestEmail(),
			    text      = self.__respbuf)
	self.__respbuf = ''
        self.__errors = 0
        self.__NoMailCmdResponse = 0

    def ProcessPasswordCmd(self, args, cmd, mail):
        if len(args) not in [0,2]:
	    self.AddError("Usage: password [<oldpw> <newpw>]")
	    return
        sender = mail.GetSender()
        if len(args) == 0:
            # Mail user's password to user
            user = self.FindUser(sender)
            if user and self.passwords.has_key(user):
                self.AddToResponse("You are subscribed as %s,\n"
                                   "  with password: %s" %
                                   (user, self.passwords[user]),
                                   trunc=0)
            else:
                self.AddError("Found no password for %s" %sender, trunc=0)
            return
        # Try to change password
	try:
            self.ConfirmUserPassword(sender, args[0])
	    self.ChangeUserPassword(sender, args[1], args[1])
	    self.AddToResponse('Succeeded.')
	except Errors.MMListNotReady:
	    self.AddError("List is not functional.")
	except Errors.MMNotAMemberError:
	    self.AddError("%s isn't subscribed to this list." % sender,
                          trunc=0)
	except Errors.MMBadPasswordError:
	    self.AddError("You gave the wrong password.")
	except Errors.MMBadUserError:
            self.AddError("Bad user - %s." % sender, trunc=0)

    def ProcessOptionsCmd(self, args, cmd, mail):
	sender = self.FindUser(mail.GetSender())
	if not sender:
	    self.AddError("%s is not a member of the list." %
                          mail.GetSender(), trunc=0)
	    return
        for option in options:
            if self.GetUserOption(sender, option_info[option]):
                value = 'on'
            else:
                value = 'off'
            self.AddToResponse('%8s: %s' % (option, value))
	self.AddToResponse("\n"
                           "To change an option, do: "
                           "set <option> <on|off> <password>\n"
                           "\n"
                           "Option explanations:\n"
                           "--------------------")
	for option in options:
	    self.AddToResponse(option + ':')
            self.AddToResponse(Utils.wrap(option_descs[option]) + '\n',
                               trunc=0, prefix="  ")
	    
    def ProcessSetCmd(self, args, cmd, mail):
	def ShowSetUsage(s=self, od = option_descs):
            options = od.keys()
            options.sort()
            desc_text = ""
	    for option in options:
		desc_text = (desc_text +
                             "%12s:  %s\n" % (option, od[option]))
	    s.AddError("Usage: set <option> <on|off> <password>\n"
                       "Valid options are:\n" +
                       desc_text)
	if len(args) <> 3:
	    ShowSetUsage()
	    return
	if args[1] == 'on':
	    value = 1
	elif args[1] == 'off':
	    value = 0
	else:
	    ShowSetUsage()
	    return
	try:
	    sender = self.FindUser(mail.GetSender())
	    self.ConfirmUserPassword(sender, args[2])
	except Errors.MMNotAMemberError:
	    self.AddError("%s isn't subscribed to this list."
			  % mail.GetSender(), trunc=0)
	    return
	except Errors.MMBadPasswordError:
	    self.AddError("You gave the wrong password.")
            return
	if args[0] == 'digest':
	    try:
		self.SetUserDigest(mail.GetSender(), value)
		self.AddToResponse("Succeeded.")
	    except Errors.MMAlreadyDigested:
		self.AddError("You are already receiving digests.")
	    except Errors.MMAlreadyUndigested:
		self.AddError("You already have digests off.")
	    except Errors.MMBadEmailError:
		self.AddError("Email address '%s' not accepted by Mailman." % 
			      mail.GetSender(), trunc=0)
	    except Errors.MMMustDigestError:
		self.AddError("List only accepts digest members.")
	    except Errors.MMCantDigestError:
		self.AddError("List doesn't accept digest members.")
	    except Errors.MMListNotReady:
		self.AddError("List is not functional.")
	    except Errors.MMNoSuchUserError:
		self.AddError("%s is not subscribed to this list."
                              % mail.GetSender(), trunc=0)
	    except Errors.MMNeedApproval:
		self.AddApprovalMsg(cmd)
	elif not option_info.has_key(args[0]):
            ShowSetUsage()
            return
        # for backwards compatibility
        if args[0] == 'norcv':
            args[0] = 'notmetoo'
        self.SetUserOption(sender, option_info[args[0]], value)
        self.AddToResponse("Succeeded.")
	    
    def ProcessListsCmd(self, args, cmd, mail):
	if len(args) != 0:
	    self.AddError("Usage: lists")
	    return
	lists = Utils.list_names()
	lists.sort()
	self.AddToResponse("\nPublic mailing lists run by mailman@%s"
			   % self.host_name, trunc=0)
	for listname in lists:
	    if listname == self._internal_name:
		listob = self
	    else:
                try:
                    listob = MailList.MailList(listname, lock=0)
                except Errors.MMUnknownListError:
                    continue
	    # We can mention this list if you already know about it.
	    if not listob.advertised and listob <> self: 
		continue
            self.AddToResponse(listob.real_name + ':')
            self.AddToResponse('\trequests to: ' + listob.GetRequestEmail(),
                               trunc=0)
            if listob.description:
                self.AddToResponse('\tdescription: ' + listob.description,
                                   trunc=0)
	
    def ProcessInfoCmd(self, args, cmd, mail):
	if len(args) != 0:
	    self.AddError("Usage: info\n"
                          "To get info for a particular list, "
                          "send your request to\n"
                          "the '-request' address for that list, or "
                          "use the 'lists' command\n"
                          "to get info for all the lists.")
	    return

	if self.private_roster and not self.IsMember(mail.GetSender()):
	    self.AddError("Private list: only members may see info.")
	    return

        msg = Utils.wrap('''
For more complete info about the %(listname)s mailing list, including
background and instructions for subscribing to and using it, visit:

    %(url)s

''' % {'listname': self.real_name,
       'url'     : self.GetAbsoluteScriptURL('listinfo'),
       })
        self.AddToResponse(msg, trunc=0)

	if not self.info:
	    self.AddToResponse("No other details are available.")
	else:
            self.AddToResponse(Utils.wrap(self.info), trunc=0)
	
    def ProcessWhoCmd(self, args, cmd, mail):
	if len(args) != 0:
	    self.AddError("Usage: who\n"
                          "To get subscribership for a particular list, "
                          "send your request\n"
                          "to the '-request' address for that list.")
	    return
	if self.private_roster == 2:
	    self.AddError("Private list: No one may see subscription list.")
	    return
	if self.private_roster and not self.IsMember(mail.GetSender()):
	    self.AddError("Private list: only members may see list "
			  "of subscribers.")
	    return
        digestmembers = self.GetDigestMembers()
        members = self.GetMembers()
	if not len(digestmembers) and not len(members):
	    self.AddToResponse("NO MEMBERS.")
	    return
	
	def AddTab(str):
	    return '\t' + str
	def NotHidden(x, s=self, v=mm_cfg.ConcealSubscription):
	    return not s.GetUserOption(x, v)

	if len(digestmembers):
            digestmembers.sort()
	    self.AddToResponse("Digest Members:\n" +
                               string.join(map(AddTab,
                                               filter(NotHidden,
                                                      digestmembers)),
                                           "\n"), trunc=0)
	if len(members):
            members.sort()
	    self.AddToResponse("Non-Digest Members:\n" +
                               string.join(map(AddTab,
                                               filter(NotHidden, members)),
                                           "\n"), trunc=0)

    def ProcessUnsubscribeCmd(self, args, cmd, mail):
	if not len(args):
	    self.AddError("Usage: unsubscribe <password> [<email-address>]")
	    return
	if len(args) > 2:
	    self.AddError("Usage: unsubscribe <password> [<email-address>]\n"
                          "To unsubscribe from a particular list, "
                          "send your request\n"
                          "to the '-request' address for that list.")
	    return
	if len(args) == 2:
	    addr = args[1]
	else:
	    addr = mail.GetSender()
	try:
	    self.ConfirmUserPassword(addr, args[0])
	    self.DeleteMember(addr, "mailcmd")
	    self.AddToResponse("Succeeded.")
	except Errors.MMListNotReady:
	    self.AddError("List is not functional.")
	except (Errors.MMNoSuchUserError, Errors.MMNotAMemberError):
	    self.AddError("%s is not subscribed to this list." % addr,
                          trunc=0)
	except Errors.MMBadPasswordError:
	    self.AddError("You gave the wrong password.")

    def ProcessSubscribeCmd(self, args, cmd, mail):
        """Parse subscription request and send confirmation request."""
	digest = self.digest_is_default
        password = ""
        address = ""
        done_digest = 0
	if not len(args):
	    password = Utils.MakeRandomPassword()
        elif len(args) > 3:
            self.AddError("Usage: subscribe [password] "
                          "[digest|nodigest] [address=<email-address>]",
                          trunc=0)
            return
        else:
            for arg in args:
                if string.lower(arg) == 'digest' and not done_digest:
                    digest = 1
                    done_digest = 1
                elif string.lower(arg) == 'nodigest' and not done_digest:
                    digest = 0
                    done_digest = 1
                elif string.lower(arg)[:8] == 'address=' and not address:
                    address = Utils.LCDomain(arg[8:])
                elif not password:
                    password = arg
                else:
                    self.AddError("Usage: subscribe [password] "
                                  "[digest|nodigest] "
                                  "[address=<email-address>]")
                    return
        if not password:
            password = Utils.MakeRandomPassword()
        if not address:
            subscribe_address = Utils.LCDomain(mail.GetSender())
        else:
            subscribe_address = address
        remote = mail.GetSender()
        try:
            self.AddMember(subscribe_address, password, digest, remote)
            self.Save()
        except Errors.MMSubscribeNeedsConfirmation:
            #
            # the confirmation message that's been sent takes place 
            # of the results of the mail command message
            #
            self.__NoMailCmdResponse = 1
        except Errors.MMNeedApproval, admin_email:
            self.AddToResponse(
                "your subscription request has been forwarded the list "
                "administrator\n"
                "at %s for review." % admin_email, trunc=0)
        except Errors.MMBadEmailError:
            self.AddError("Mailman won't accept the given email "
                          "address as a valid address.\n"
                          "(Does it have an @ in it???)")
        except Errors.MMListNotReady:
            self.AddError("The list is not fully functional, and "
                          "can not accept subscription\n"
                          "requests.")
        except Errors.MMHostileAddress:
            self.AddError("Your subscription is not allowed because\n"
                          "the email address you gave is insecure.")
        except Errors.MMAlreadyAMember:
            self.AddError("You are already subscribed!")
        except Errors.MMCantDigestError:
            self.AddError("No one can subscribe to the digest of this list!")
        except Errors.MMMustDigestError:
            self.AddError("This list only supports digest subscriptions!")
        else:
            #
            # if the list sends a welcome message, we don't need a response
            # from the mailcommand handler.
            #
            if self.send_welcome_msg:
                self.__NoMailCmdResponse = 1
            else:
                self.AddToResponse("Succeeded")



    def ProcessConfirmCmd(self, args, cmd, mail):
        """Validate confirmation and carry out the subscription."""
        if len(args) != 1:
            self.AddError("Usage: confirm <confirmation number>\n")
            return
        try:
            cookie = string.atoi(args[0])
        except:
            self.AddError("Usage: confirm <confirmation number>\n")
            return
        try:
            self.ProcessConfirmation(cookie)
        except Errors.MMBadConfirmation:
            from math import floor
            # Express in days, rounded to three places:
            expiredays = floor((mm_cfg.PENDING_REQUEST_LIFE / (60 * 60 * 24.0))
                               * 1000) / 1000
            if floor(expiredays) == expiredays:
                expiredays = int(expiredays)
            self.AddError("Invalid confirmation number!\n"
                          "Note that confirmation numbers expire %s days"
                          " after initial request.\n"
                          "Please check date and number and try again,"
                          " from the start if necessary."
                          % expiredays, trunc=0)
        except Errors.MMNeedApproval, admin_addr:
            self.AddToResponse("Your request has been forwarded to the list "
                               "administrator for approval")
        except Errors.MMAlreadyAMember:
            # Some other subscription request for this address has
            # already succeeded.
            self.AddError("You are already subscribed!")
        else:
            #
            # if the list sends a welcome message, we don't need a response
            # from the mailcommand handler.
            #
            if self.send_welcome_msg:
                self.__NoMailCmdResponse = 1
            else:
                self.AddToResponse("Succeeded")


    def AddApprovalMsg(self, cmd):
        text = Utils.maketext(
            'approve.txt',
            {'requestaddr': self.GetRequestEmail(),
             'cmd'        : cmd,
             'adminaddr'  : self.GetAdminEmail(),
             })
        self.AddError(text, trunc=0)

    def ProcessHelpCmd(self, args, cmd, mail):
        text = Utils.maketext(
            'help.txt',
            {'listname'    : self.real_name,
             'version'     : mm_cfg.VERSION,
             'listinfo_url': self.GetAbsoluteScriptURL('listinfo'),
             'requestaddr' : self.GetRequestEmail(),
             'adminaddr'   : self.GetAdminEmail(),
             })
        self.AddToResponse(text, trunc=0)
