#! /usr/bin/env python

# PyKota - Print Quotas for CUPS
#
# (c) 2003 Jerome Alet <alet@librelogiciel.com>
# You're welcome to redistribute this software under the
# terms of the GNU General Public Licence version 2.0
# or, at your option, any higher version.
#
# You can read the complete GNU GPL in the file COPYING
# which should come along with this software, or visit
# the Free Software Foundation's WEB site http://www.fsf.org
#
# $Id$
#
# $Log$
# Revision 1.8  2003/02/06 09:19:02  jalet
# More robust behavior (hopefully) when the user or printer is not managed
# correctly by the Quota System : e.g. cupsFilter added in ppd file, but
# printer and/or user not 'yet?' in storage.
#
# Revision 1.7  2003/02/06 00:00:45  jalet
# Now includes the printer name in email messages
#
# Revision 1.6  2003/02/05 23:55:02  jalet
# Cleaner email messages
#
# Revision 1.5  2003/02/05 23:45:09  jalet
# Better DateTime manipulation wrt grace delay
#
# Revision 1.4  2003/02/05 23:26:22  jalet
# Incorrect handling of grace delay
#
# Revision 1.3  2003/02/05 22:16:20  jalet
# DEVICE_URI is undefined outside of CUPS, i.e. for normal command line tools
#
# Revision 1.2  2003/02/05 22:10:29  jalet
# Typos
#
# Revision 1.1  2003/02/05 21:28:17  jalet
# Initial import into CVS
#
#
#

import sys
import os
import smtplib

from mx import DateTime

from pykota import config
from pykota import storage
from pykota import logger

class PyKotaToolError(Exception):
    """An exception for PyKota config related stuff."""
    def __init__(self, message = ""):
        self.message = message
        Exception.__init__(self, message)
    def __repr__(self):
        return self.message
    __str__ = __repr__
    
class PyKotaTool :    
    """Base class for all PyKota command line tools."""
    def __init__(self, isfilter=0) :
        """Initializes the command line tool."""
        self.config = config.PyKotaConfig(os.environ.get("CUPS_SERVERROOT", "/etc/cups"))
        self.logger = logger.openLogger(self.config)
        self.storage = storage.openConnection(self.config, asadmin=(not isfilter))
        self.printername = os.environ.get("PRINTER", None)
        self.smtpserver = self.config.getSMTPServer()
        self.admin = self.config.getAdmin()
        self.adminmail = self.config.getAdminMail()
        
    def sendMessage(self, touser, fullmessage) :
        """Sends an email message containing headers to some user."""
        if "@" not in touser :
            touser = "%s@%s" % (touser, self.smtpserver)
        server = smtplib.SMTP(self.smtpserver)
        server.sendmail(self.adminmail, [touser], fullmessage)
        server.quit()
        
    def sendMessageToUser(self, username, subject, message) :
        """Sends an email message to a user."""
        message += "\n\nPlease contact your system administrator :\n\n\t%s - <%s>\n" % (self.admin, self.adminmail)
        self.sendMessage(username, "Subject: %s\n\n%s" % (subject, message))
        
    def sendMessageToAdmin(self, subject, message) :
        """Sends an email message to the Print Quota administrator."""
        self.sendMessage(self.adminmail, "Subject: %s\n\n%s" % (subject, message))
        
    def checkUserPQuota(self, username, printername) :
        """Checks the user quota on a printer and deny or accept the job."""
        now = DateTime.now()
        quota = self.storage.getUserPQuota(username, printername)
        if quota is None :
            # Unknown user or printer or combination
            policy = self.config.getPrinterPolicy(printername)
            if policy in [None, "ALLOW"] :
                action = "ALLOW"
            else :    
                action = "DENY"
            self.logger.log_message("Unable to match user %s on printer %s, applying default policy (%s)" % (username, printername, action), "warn")
            return (action, None, None)
        else :    
            pagecounter = quota["pagecounter"]
            softlimit = quota["softlimit"]
            hardlimit = quota["hardlimit"]
            datelimit = quota["datelimit"]
            if datelimit is not None :
                datelimit = DateTime.ISO.ParseDateTime(datelimit)
            if softlimit is not None :
                if pagecounter < softlimit :
                    action = "ALLOW"
                elif hardlimit is not None :
                     gracedelay = self.config.getGraceDelay()
                     if softlimit <= pagecounter < hardlimit :    
                         if datelimit is None :
                             datelimit = now + gracedelay
                             self.storage.doQuery("UPDATE userpquota SET datelimit=%s::DATETIME WHERE userid=%s AND printerid=%s;" % (self.doQuote("%04i-%02i-%02i %02i:%02i:%02i" % (datelimit.year, datelimit.month, datelimit.day, datelimit.hour, datelimit.minute, datelimit.second)), self.doQuote(self.getUserId(username)), self.doQuote(self.getPrinterId(printername))))
                         if (now + gracedelay) < datelimit :
                             action = "WARN"
                         else :    
                             action = "DENY"
                     else :         
                         action = "DENY"
                else :        
                    action = "DENY"
            else :        
                action = "ALLOW"
            return (action, (hardlimit - pagecounter), datelimit)
    
    def warnQuotaPrinter(self, username) :
        """Checks a user quota and send him a message if quota is exceeded on current printer."""
        (action, grace, gracedate) = self.checkUserPQuota(username, self.printername)
        if action == "DENY" :
            if (grace is not None) and (gracedate is not None) :
                # only when both user and printer are known
                adminmessage = "Print Quota exceeded for user %s on printer %s" % (username, self.printername)
                self.logger.log_message(adminmessage)
                self.sendMessageToUser(username, "Print Quota Exceeded", "You are not allowed to print anymore because\nyour Print Quota is exceeded on printer %s." % self.printername)
                self.sendMessageToAdmin("Print Quota", adminmessage)
        elif action == "WARN" :    
            adminmessage = "Print Quota soft limit exceeded for user %s on printer %s" % (username, self.printername)
            self.logger.log_message(adminmessage)
            self.sendMessageToUser(username, "Print Quota Exceeded", "You will soon be forbidden to print anymore because\nyour Print Quota is almost reached on printer %s." % self.printername)
            self.sendMessageToAdmin("Print Quota", adminmessage)
        return action