#! /usr/bin/env python
# -*- coding: UTF-8 -*-
#
# PyKota : Print Quotas for CUPS
#
# (c) 2003, 2004, 2005, 2006, 2007 Jerome Alet <alet@librelogiciel.com>
# 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 3 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, see <http://www.gnu.org/licenses/>.
#
# $Id$
#
#

import sys
import os
import pwd
import grp
import socket
import signal

from pykota.tool import Tool, PyKotaToolError, PyKotaCommandLineError, crashed, N_

__doc__ = N_("""pkturnkey v%(__version__)s (c) %(__years__)s %(__author__)s

A turn key tool for PyKota. When launched, this command will initialize
PyKota's database with all existing print queues and some or all users.
For now, no prices or limits are set, so printing is fully accounted
for, but not limited. That's why you'll probably want to also use
edpykota once the database has been initialized.

command line usage :

  pkturnkey [options] [printqueues names]

options :

  -v | --version       Prints pkturnkey version number then exits.
  -h | --help          Prints this message then exits.
  
  -c | --doconf        Give hints about what to put into pykota.conf
  
  -d | --dousers       Manages users accounts as well.
  
  -D | --dogroups      Manages users groups as well.
                       Implies -d | --dousers.
  
  -e | --emptygroups   Includes empty groups.
  
  -f | --force         Modifies the database instead of printing what
                       it would do.
                       
  -u | --uidmin uid    Only adds users whose uid is greater than or equal to
                       uid. You can pass an username there as well, and its
                       uid will be used automatically.
                       If not set, 0 will be used automatically.
                       Implies -d | --dousers.
                       
  -U | --uidmax uid    Only adds users whose uid is lesser than or equal to
                       uid. You can pass an username there as well, and its
                       uid will be used automatically.
                       If not set, a large value will be used automatically.
                       Implies -d | --dousers.

  -g | --gidmin gid    Only adds groups whose gid is greater than or equal to
                       gid. You can pass a groupname there as well, and its
                       gid will be used automatically.
                       If not set, 0 will be used automatically.
                       Implies -D | --dogroups.
                       
  -G | --gidmax gid    Only adds groups whose gid is lesser than or equal to
                       gid. You can pass a groupname there as well, and its
                       gid will be used automatically.
                       If not set, a large value will be used automatically.
                       Implies -D | --dogroups.

examples :                              

  $ pkturnkey --dousers --uidmin jerome

  Will simulate the initialization of PyKota's database will all existing
  printers and print accounts for all users whose uid is greater than
  or equal to jerome's one. Won't manage any users group.
  
  To REALLY initialize the database instead of simulating it, please
  use the -f | --force command line switch.
  
  You can limit the initialization to only a subset of the existing
  printers, by passing their names at the end of the command line.
""")
        
class PKTurnKey(Tool) :
    """A class for an initialization tool."""
    def listPrinters(self, namestomatch) :
        """Returns a list of tuples (queuename, deviceuri) for all existing print queues."""
        self.printInfo("Extracting all print queues.")
        result = os.popen("lpstat -v", "r")
        lines = result.readlines()
        result.close()
        printers = []
        for line in lines :
            (begin, end) = line.split(':', 1)
            deviceuri = end.strip()
            queuename = begin.split()[-1]
            if self.matchString(queuename, namestomatch) :
                printers.append((queuename, deviceuri))
            else :    
                self.printInfo("Print queue %s skipped." % queuename)
        return printers    
        
    def listUsers(self, uidmin, uidmax) :    
        """Returns a list of users whose uids are between uidmin and uidmax."""
        self.printInfo("Extracting all users whose uid is between %s and %s." % (uidmin, uidmax))
        return [(entry[0], entry[3]) for entry in pwd.getpwall() if uidmin <= entry[2] <= uidmax]
        
    def listGroups(self, gidmin, gidmax, users) :
        """Returns a list of groups whose gids are between gidmin and gidmax."""
        self.printInfo("Extracting all groups whose gid is between %s and %s." % (gidmin, gidmax))
        groups = [(entry[0], entry[2], entry[3]) for entry in grp.getgrall() if gidmin <= entry[2] <= gidmax]
        gidusers = {}
        usersgid = {}
        for u in users :
            gidusers.setdefault(u[1], []).append(u[0])
            usersgid.setdefault(u[0], []).append(u[1]) 
            
        membership = {}    
        for g in range(len(groups)) :
            (gname, gid, members) = groups[g]
            newmembers = {}
            for m in members :
                newmembers[m] = m
            try :
                usernames = gidusers[gid]
            except KeyError :    
                pass
            else :    
                for username in usernames :
                    if not newmembers.has_key(username) :
                        newmembers[username] = username
            for member in newmembers.keys() :            
                if not usersgid.has_key(member) :
                    del newmembers[member]
            membership[gname] = newmembers.keys()
        return membership
        
    def runCommand(self, command, dryrun) :    
        """Launches an external command."""
        self.printInfo("%s" % command)
        if not dryrun :    
            os.system(command)
            
    def createPrinters(self, printers, dryrun=0) :    
        """Creates all printers in PyKota's database."""
        if printers :
            args = open("/tmp/pkprinters.args", "w")
            args.write('--add\n--cups\n--skipexisting\n--description\n"printer created from pkturnkey"\n')
            args.write("%s\n" % "\n".join(['"%s"' % p[0] for p in printers]))
            args.close()
            self.runCommand("pkprinters --arguments /tmp/pkprinters.args", dryrun)
        
    def createUsers(self, users, printers, dryrun=0) :
        """Creates all users in PyKota's database."""
        if users :
            args = open("/tmp/pkusers.users.args", "w")
            args.write('--add\n--skipexisting\n--description\n"user created from pkturnkey"\n--limitby\nnoquota\n')
            args.write("%s\n" % "\n".join(['"%s"' % u for u in users]))
            args.close()
            self.runCommand("pkusers --arguments /tmp/pkusers.users.args", dryrun)
            
            printersnames = [p[0] for p in printers]
            args = open("/tmp/edpykota.users.args", "w")
            args.write('--add\n--skipexisting\n--noquota\n--printer\n')
            args.write("%s\n" % ",".join(['"%s"' % p for p in printersnames]))
            args.write("%s\n" % "\n".join(['"%s"' % u for u in users]))
            args.close()
            self.runCommand("edpykota --arguments /tmp/edpykota.users.args", dryrun)
            
    def createGroups(self, groups, printers, dryrun=0) :
        """Creates all groups in PyKota's database."""
        if groups :
            args = open("/tmp/pkusers.groups.args", "w")
            args.write('--groups\n--add\n--skipexisting\n--description\n"group created from pkturnkey"\n--limitby\nnoquota\n')
            args.write("%s\n" % "\n".join(['"%s"' % g for g in groups]))
            args.close()
            self.runCommand("pkusers --arguments /tmp/pkusers.groups.args", dryrun)
            
            printersnames = [p[0] for p in printers]
            args = open("/tmp/edpykota.groups.args", "w")
            args.write('--groups\n--add\n--skipexisting\n--noquota\n--printer\n')
            args.write("%s\n" % ",".join(['"%s"' % p for p in printersnames]))
            args.write("%s\n" % "\n".join(['"%s"' % g for g in groups]))
            args.close()
            self.runCommand("edpykota --arguments /tmp/edpykota.groups.args", dryrun)
            
            revmembership = {}
            for (groupname, usernames) in groups.items() :
                for username in usernames :
                    revmembership.setdefault(username, []).append(groupname)
            commands = []        
            for (username, groupnames) in revmembership.items() :        
                commands.append('pkusers --ingroups %s "%s"' \
                    % (",".join(['"%s"' % g for g in groupnames]), username))
            for command in commands :
                self.runCommand(command, dryrun)
        
    def supportsSNMP(self, hostname, community) :
        """Returns 1 if the printer accepts SNMP queries, else 0."""
        pageCounterOID = "1.3.6.1.2.1.43.10.2.1.4.1.1"  # SNMPv2-SMI::mib-2.43.10.2.1.4.1.1
        try :
            from pysnmp.entity.rfc3413.oneliner import cmdgen
        except ImportError :    
            hasV4 = False
            try :
                from pysnmp.asn1.encoding.ber.error import TypeMismatchError
                from pysnmp.mapping.udp.role import Manager
                from pysnmp.proto.api import alpha
            except ImportError :    
                sys.stderr.write("pysnmp doesn't seem to be installed. SNMP checks will be ignored !\n")
                return 0
        else :        
            hasV4 = True
            
        if hasV4 :    
            def retrieveSNMPValues(hostname, community) :
                """Retrieves a printer's internal page counter and status via SNMP."""
                errorIndication, errorStatus, errorIndex, varBinds = \
                     cmdgen.CommandGenerator().getCmd(cmdgen.CommunityData("pykota", community, 0), \
                                                      cmdgen.UdpTransportTarget((hostname, 161)), \
                                                      tuple([int(i) for i in pageCounterOID.split('.')]))
                if errorIndication :                                                  
                    raise "No SNMP !"
                elif errorStatus :    
                    raise "No SNMP !"
                else :                                 
                    self.SNMPOK = True
        else :
            def retrieveSNMPValues(hostname, community) :    
                """Retrieves a printer's internal page counter and status via SNMP."""
                ver = alpha.protoVersions[alpha.protoVersionId1]
                req = ver.Message()
                req.apiAlphaSetCommunity(community)
                req.apiAlphaSetPdu(ver.GetRequestPdu())
                req.apiAlphaGetPdu().apiAlphaSetVarBindList((pageCounterOID, ver.Null()))
                tsp = Manager()
                try :
                    tsp.sendAndReceive(req.berEncode(), \
                                       (hostname, 161), \
                                       (handleAnswer, req))
                except :    
                    raise "No SNMP !"
                tsp.close()
            
            def handleAnswer(wholemsg, notusedhere, req):
                """Decodes and handles the SNMP answer."""
                ver = alpha.protoVersions[alpha.protoVersionId1]
                rsp = ver.Message()
                try :
                    rsp.berDecode(wholemsg)
                except TypeMismatchError, msg :    
                    raise "No SNMP !"
                else :
                    if req.apiAlphaMatch(rsp):
                        errorStatus = rsp.apiAlphaGetPdu().apiAlphaGetErrorStatus()
                        if errorStatus:
                            raise "No SNMP !"
                        else:
                            self.values = []
                            for varBind in rsp.apiAlphaGetPdu().apiAlphaGetVarBindList():
                                self.values.append(varBind.apiAlphaGetOidVal()[1].rawAsn1Value)
                            try :    
                                pagecounter = self.values[0]
                            except :
                                raise "No SNMP !"
                            else :    
                                self.SNMPOK = 1
                                return 1
            
        self.SNMPOK = 0
        try :
            retrieveSNMPValues(hostname, community)
        except :    
            self.SNMPOK = 0
        return self.SNMPOK
        
    def supportsPJL(self, hostname, port) :
        """Returns 1 if the printer accepts PJL queries over TCP, else 0."""
        def alarmHandler(signum, frame) :
            raise "Timeout !"
        
        pjlsupport = 0
        signal.signal(signal.SIGALRM, alarmHandler)
        signal.alarm(2) # wait at most 2 seconds
        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        try :
            s.connect((hostname, port))
            s.send("\033%-12345X@PJL INFO STATUS\r\n\033%-12345X")
            answer = s.recv(1024)
            if not answer.startswith("@PJL") :
                raise "No PJL !"
        except :    
            pass
        else :    
            pjlsupport = 1
        s.close()
        signal.alarm(0)
        signal.signal(signal.SIGALRM, signal.SIG_IGN)
        return pjlsupport
            
    def hintConfig(self, printers) :    
        """Gives some hints about what to put into pykota.conf"""
        if not printers :
            return
        sys.stderr.flush() # ensure outputs don't mix    
        print     
        print "--- CUT ---"
        print "# Here are some lines that we suggest you add at the end"
        print "# of the pykota.conf file. These lines gives possible"
        print "# values for the way print jobs' size will be computed."
        print "# NB : it is possible that a manual configuration gives"
        print "# better results for you. As always, your mileage may vary."
        print "#"
        for (name, uri) in printers :
            print "[%s]" % name
            accounter = "software()"
            try :
                uri = uri.split("cupspykota:", 2)[-1]
            except (ValueError, IndexError) :    
                pass
            else :    
                while uri and uri.startswith("/") :
                    uri = uri[1:]
                try :
                    (backend, destination) = uri.split(":", 1) 
                    if backend not in ("ipp", "http", "https", "lpd", "socket") :
                        raise ValueError
                except ValueError :    
                    pass
                else :        
                    while destination.startswith("/") :
                        destination = destination[1:]
                    checkauth = destination.split("@", 1)    
                    if len(checkauth) == 2 :
                        destination = checkauth[1]
                    parts = destination.split("/")[0].split(":")
                    if len(parts) == 2 :
                        (hostname, port) = parts
                        try :
                            port = int(port)
                        except ValueError :
                            port = 9100
                    else :    
                        (hostname, port) = parts[0], 9100
                        
                    if self.supportsSNMP(hostname, "public") :
                        accounter = "hardware(snmp)"
                    elif self.supportsPJL(hostname, 9100) :
                        accounter = "hardware(pjl)"
                    elif self.supportsPJL(hostname, 9101) :
                        accounter = "hardware(pjl:9101)"
                    elif self.supportsPJL(hostname, port) :    
                        accounter = "hardware(pjl:%s)" % port
                    
            print "preaccounter : software()" 
            print "accounter : %s" % accounter
            print
        print "--- CUT ---"
        
    def main(self, names, options) :
        """Intializes PyKota's database."""
        if not self.config.isAdmin :
            raise PyKotaCommandLineError, "%s : %s" % (pwd.getpwuid(os.geteuid())[0], \
                                   _("You're not allowed to use this command."))
            
        if not names :
            names = ["*"]
            
        self.printInfo(_("Please be patient..."))
        dryrun = not options["force"]
        if dryrun :
            self.printInfo(_("Don't worry, the database WILL NOT BE MODIFIED."))
        else :    
            self.printInfo(_("Please WORRY NOW, the database WILL BE MODIFIED."))
            
        if options["dousers"] :    
            if not options["uidmin"] :    
                self.printInfo(_("System users will have a print account as well !"), "warn")
                uidmin = 0
            else :    
                try :
                    uidmin = int(options["uidmin"])
                except :    
                    try :
                        uidmin = pwd.getpwnam(options["uidmin"])[2]
                    except KeyError, msg :    
                        raise PyKotaCommandLineError, _("Unknown username %s : %s") \
                                                   % (options["uidmin"], msg)
                        
            if not options["uidmax"] :    
                uidmax = sys.maxint
            else :    
                try :
                    uidmax = int(options["uidmax"])
                except :    
                    try :
                        uidmax = pwd.getpwnam(options["uidmax"])[2]
                    except KeyError, msg :    
                        raise PyKotaCommandLineError, _("Unknown username %s : %s") \
                                                   % (options["uidmax"], msg)
            
            if uidmin > uidmax :            
                (uidmin, uidmax) = (uidmax, uidmin)
            users = self.listUsers(uidmin, uidmax)
        else :    
            users = []
            
        if options["dogroups"] :    
            if not options["gidmin"] :    
                self.printInfo(_("System groups will have a print account as well !"), "warn")
                gidmin = 0
            else :    
                try :
                    gidmin = int(options["gidmin"])
                except :    
                    try :
                        gidmin = grp.getgrnam(options["gidmin"])[2]
                    except KeyError, msg :    
                        raise PyKotaCommandLineError, _("Unknown groupname %s : %s") \
                                                   % (options["gidmin"], msg)
                        
            if not options["gidmax"] :    
                gidmax = sys.maxint
            else :    
                try :
                    gidmax = int(options["gidmax"])
                except :    
                    try :
                        gidmax = grp.getgrnam(options["gidmax"])[2]
                    except KeyError, msg :    
                        raise PyKotaCommandLineError, _("Unknown groupname %s : %s") \
                                                   % (options["gidmax"], msg)
            
            if gidmin > gidmax :            
                (gidmin, gidmax) = (gidmax, gidmin)
            groups = self.listGroups(gidmin, gidmax, users)
            if not options["emptygroups"] :
                for (groupname, members) in groups.items() :
                    if not members :
                        del groups[groupname]
        else :    
            groups = []
            
        printers = self.listPrinters(names)
        if printers :
            self.createPrinters(printers, dryrun)
            self.createUsers([entry[0] for entry in users], printers, dryrun)
            self.createGroups(groups, printers, dryrun)
        
        if dryrun :
            self.printInfo(_("Simulation terminated."))
        else :    
            self.printInfo(_("Database initialized !"))
       
        if options["doconf"] :    
            self.hintConfig(printers)
                    
                     
if __name__ == "__main__" : 
    retcode = 0
    try :
        short_options = "hvdDefu:U:g:G:c"
        long_options = ["help", "version", "dousers", "dogroups", \
                        "emptygroups", "force", "uidmin=", "uidmax=", \
                        "gidmin=", "gidmax=", "doconf"]
        
        # Initializes the command line tool
        manager = PKTurnKey(doc=__doc__)
        manager.deferredInit()
        
        # parse and checks the command line
        (options, args) = manager.parseCommandline(sys.argv[1:], \
                                                   short_options, \
                                                   long_options, \
                                                   allownothing=1)
        
        # sets long options
        options["help"] = options["h"] or options["help"]
        options["version"] = options["v"] or options["version"]
        options["dousers"] = options["d"] or options["dousers"]
        options["dogroups"] = options["D"] or options["dogroups"]
        options["emptygroups"] = options["e"] or options["emptygroups"]
        options["force"] = options["f"] or options["force"]
        options["uidmin"] = options["u"] or options["uidmin"]
        options["uidmax"] = options["U"] or options["uidmax"]
        options["gidmin"] = options["g"] or options["gidmin"]
        options["gidmax"] = options["G"] or options["gidmax"]
        options["doconf"] = options["c"] or options["doconf"]
        
        if options["uidmin"] or options["uidmax"] :
            if not options["dousers"] :
                manager.printInfo(_("The --uidmin or --uidmax command line option implies --dousers as well."), "warn")
            options["dousers"] = 1    
            
        if options["gidmin"] or options["gidmax"] :
            if not options["dogroups"] :
                manager.printInfo(_("The --gidmin or --gidmax command line option implies --dogroups as well."), "warn")
            options["dogroups"] = 1
        
        if options["dogroups"] :
            if not options["dousers"] :
                manager.printInfo(_("The --dogroups command line option implies --dousers as well."), "warn")
            options["dousers"] = 1    
            
        if options["help"] :
            manager.display_usage_and_quit()
        elif options["version"] :
            manager.display_version_and_quit()
        else :
            retcode = manager.main(args, options)
    except KeyboardInterrupt :        
        sys.stderr.write("\nInterrupted with Ctrl+C !\n")
        retcode = -3
    except PyKotaCommandLineError, msg :    
        sys.stderr.write("%s : %s\n" % (sys.argv[0], msg))
        retcode = -2
    except SystemExit :        
        pass
    except :
        try :
            manager.crashed("pkturnkey failed")
        except :    
            crashed("pkturnkey failed")
        retcode = -1

    try :
        manager.storage.close()
    except (TypeError, NameError, AttributeError) :    
        pass
        
    sys.exit(retcode)