#!/usr/bin/python
"""
chfn - change real user name and information

This utility imitates chfn(1) from the shadow password suite, but makes its
changes in the LDAP directory rather than in the passwd file.

When run from an unprivileged account, authentication will be performed
before the account information is changed.
"""
import os, sys, pwd, getopt, PAM
from ceo import accounts
from ceo.excep import InvalidArgument

progname = os.path.basename(sys.argv[0])

OPTION_MAP = {
            '-f': 'fullname',
            '-r': 'roomnumber',
            '-w': 'workphone',
            '-h': 'homephone',
            '-o': 'other'
}
LONG_NAMES = [
        ('fullname', 'Full Name'),
        ('roomnumber', 'Room Number'),
        ('workphone', 'Work Phone'),
        ('homephone', 'Home Phone'),
        ('other', 'Other')
]
READONLY_FIELDS = [ 'fullname', 'other' ]

def usage():
    umesg = "Usage: %s [-f full name] [-r room no] [-w work ph] " + \
            "[-h home ph] [-o other] [user]"
    print umesg % progname
    sys.exit(2)


def whoami():
    uid = os.getuid()
    username = os.getlogin()
    if pwd.getpwnam(username).pw_uid != uid:
        username = pwd.getpwuid(uid).pw_name
    return (uid, username)

def authenticate(username):
    auth = PAM.pam()
    auth.start('chsh', username)
    try:
        auth.authenticate()
        auth.acct_mgmt()
    except PAM.error, resp:
        print "%s: %s" % (progname, resp.args[0])
        sys.exit(1)

def main():

    pwuid, pwnam = whoami()

    euid = os.geteuid()
    os.setreuid(euid, euid)

    gecos_params = {}

    try:
        options, arguments = getopt.gnu_getopt(sys.argv[1:], 'f:r:w:h:o:')
        for opt, val in options:
            gecos_params[OPTION_MAP[opt]] = val
        if len(arguments) > 1:
            usage()
        elif len(arguments) == 1:
            username = arguments[0]
        else:
            username = pwnam
    except getopt.GetoptError, e:
        usage()

    for field in READONLY_FIELDS:
        if field in gecos_params and pwuid:
            print "%s: Permission denied." % progname
            sys.exit(1)

    try:
        if pwuid and pwd.getpwnam(username).pw_uid != pwuid:
            print "%s: Permission denied." % progname
            sys.exit(1)
    except KeyError:
        print "%s: unknown user %s" % (progname, username)
        sys.exit(1)

    try:
        accounts.connect()
        gecos_raw = accounts.get_gecos(username)
        gecos = accounts.parse_gecos(gecos_raw)

        if pwuid:
            authenticate(username)

        if not gecos_params:
            print "Changing the user information for %s" % username
            print "Enter the new value, or press ENTER for the default"
            for field, longname in LONG_NAMES:
                if pwuid and field == 'other' and 'other' in READONLY_FIELDS:
                    continue
                if gecos[field] is None:
                    gecos[field] = ""
                if field in READONLY_FIELDS and pwuid:
                    print "        %s: %s" % (longname, gecos[field])
                else:
                    print "        %s: [%s]:" % (longname, gecos[field]),
                    new_value = raw_input()
                    if new_value:
                        gecos[field] = new_value.strip()
        else:
            gecos.update(gecos_params)

        gecos_raw_new = accounts.build_gecos(**gecos)
        if gecos_raw != gecos_raw_new:
            accounts.update_gecos(username, gecos_raw_new)

    except InvalidArgument, e:
        longnames = dict(LONG_NAMES)
        longname = longnames.get(e.argname, e.argname).lower()
        print "%s: invalid %s: %s" % (progname, longname, e.argval)
        sys.exit(1)

if __name__ == '__main__':
    exceps = ( accounts.ConfigurationException, accounts.LDAPException,
            accounts.KrbException, accounts.AccountException )
    try:
        main()
    except KeyboardInterrupt:
        sys.exit(130) 
    except IOError, e:
        print "%s: %s: %s" % (progname, e.filename, e.strerror)
        sys.exit(1)
    except exceps, e:
        print "%s: %s" % (progname, e)
        sys.exit(1)