#
# Chris Lumens <clumens@redhat.com>
#
# Copyright 2008 Red Hat, Inc.
#
# This copyrighted material is made available to anyone wishing to use, modify,
# copy, or redistribute it subject to the terms and conditions of the GNU
# General Public License v.2.  This program is distributed in the hope that it
# will be useful, but WITHOUT ANY WARRANTY expressed or implied, including the
# implied warranties 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., 51
# Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  Any Red Hat
# trademarks that are incorporated in the source code or documentation are not
# subject to the GNU General Public License and may only be used or replicated
# with the express permission of Red Hat, Inc. 
#
import gtk
import libuser
import os, string, sys, time
import os.path
import pwd
import unicodedata
import re
import shutil
import subprocess

from firstboot.config import *
from firstboot.constants import *
from firstboot.functions import *
from firstboot.module import *
from firstboot.pwcheck import Password
from firstboot.pwcheck import StrengthMeterWithLabel

import gettext
_ = lambda x: gettext.ldgettext("firstboot", x)
N_ = lambda x: x

sys.path.append("/usr/share/system-config-users")
import mainWindow
import userGroupCheck

class moduleClass(Module):
    def __init__(self):
        Module.__init__(self)
        self.priority = 90
        self.sidebarTitle = N_("Create User")
        self.title = N_("Create User")
        self.icon = "create-user.png"

        self.admin = libuser.admin()
        self.nisFlag = None

        self._problemFiles = []

        self._count = 0

    def _chown(self, arg, dirname, names):
        for n in names:
            try:
                os.lchown("%s/%s" % (dirname, n), arg[0], arg[1])

                # Update the UI from time to time, but not so often as to
                # really slow down the chown.
                self._count += 1
                if self._count % 100 == 0:
                    while gtk.events_pending():
                        gtk.main_iteration(False)
            except:
                self._problemFiles.append("%s/%s" % (dirname, n))

    def apply(self, interface, testing=False):
        if testing:
            return RESULT_SUCCESS

        username = self.usernameEntry.get_text()
        username = string.strip(username)

        if username == "" and self.nisFlag:
            # If they've run authconfig, don't pop up messageDialog
            return RESULT_SUCCESS

        if username == "":
            # Only allow not creating a user if there is at least
            # one non-system account already on the system
            shells = "/etc/shells"
            with open(shells) as fobj:
                login_shells = [line.strip() for line in fobj.readlines()]
                login_shells = [line for line in login_shells
                                if line and line != "/sbin/nologin"]

            users = [item[0] for item in pwd.getpwall()
                     if item[0] != "root" and item[6] in login_shells]

            if users:
                return RESULT_SUCCESS
            else:
                dlg = gtk.MessageDialog(None, 0, gtk.MESSAGE_WARNING,
                                        gtk.BUTTONS_YES_NO,
                                        _("You did not set up an user account "
                                          "capable of logging into the system."
                                          "\nAre you sure you want to continue?"))

                dlg.set_position(gtk.WIN_POS_CENTER)
                dlg.set_modal(True)
                rc = dlg.run()
                dlg.destroy()
                if rc == gtk.RESPONSE_NO:
                    self.usernameEntry.grab_focus()
                    return RESULT_FAILURE
                else:
                    return RESULT_SUCCESS

        if not userGroupCheck.isUsernameOk(username, self.usernameEntry):
            return RESULT_FAILURE

        password = self.passwordEntry.get_text()
        confirm = self.confirmEntry.get_text()

        if not password or not confirm:
            self._showErrorMessage(_("You must enter and confirm a password for this user."))
            self.passwordEntry.set_text("")
            self.confirmEntry.set_text("")
            self.passwordEntry.grab_focus()
            return RESULT_FAILURE

        if password != confirm:
            self._showErrorMessage(_("The passwords do not match.  Please enter "
                                     "the password again."))
            self.passwordEntry.set_text("")
            self.confirmEntry.set_text("")
            self.passwordEntry.grab_focus()
            return RESULT_FAILURE
        #elif not userGroupCheck.isPasswordOk(password, self.passwordEntry):
        #    return RESULT_FAILURE

        user = self.admin.lookupUserByName(username)

        # get UID_MIN from /etc/login.defs
        __ld_line = re.compile(r'^[ \t]*'      # Initial whitespace
                               r'([^ \t]+)'    # Variable name
                               r'[ \t][ \t"]*' # Separator - yes, may have multiple "s
                               r'(([^"]*)".*'  # Value, case 1 - terminated by "
                               r'|([^"]*\S)?\s*' # Value, case 2 - only drop trailing \s
                               r')$')

        res = {}
        with open('/etc/login.defs') as f:
            for line in f:
                match = __ld_line.match(line)
                if match is not None:
                    name = match.group(1)
                    if name.startswith('#'):
                        continue
                    value = match.group(3)
                    if value is None:
                        value = match.group(4)
                        if value is None:
                            value = ''
                    res[name] = value # Override previous definition

        uid_min = res.get('UID_MIN', 500)

        if user != None and user.get(libuser.UIDNUMBER)[0] < uid_min:
            self._showErrorMessage(_("The username '%s' is a reserved system "
                                     "account.  Please specify another username."
                                     % username))
            self.usernameEntry.set_text("")
            self.usernameEntry.grab_focus()
            return RESULT_FAILURE

        # If a home directory for the user already exists, offer to reuse it
        # for the new user.
        try:
            os.stat("/home/%s" % username)

            dlg = gtk.MessageDialog(None, 0, gtk.MESSAGE_WARNING, gtk.BUTTONS_YES_NO,
                                    _("A home directory for user %s already exists. "
                                      "Would you like to continue, making the new "
                                      "user the owner of this directory and all its "
                                      "contents?  Doing so may take a while to reset "
                                      "permissions and any SELinux labels.  Would "
                                      "you like to reuse this home directory?  If "
                                      "not, please choose a different username.") % username)
            dlg.set_position(gtk.WIN_POS_CENTER)
            dlg.set_modal(True)

            rc = dlg.run()
            dlg.destroy()

            if rc == gtk.RESPONSE_NO:
                self.usernameEntry.set_text("")
                self.usernameEntry.grab_focus()
                return RESULT_FAILURE

            mkhomedir = False
        except:
            mkhomedir = True

        # If we get to this point, all the input seems to be valid.
        # Let's add the user.
        if user == None:
            #if the user doesn't already exist
            userEnt = self.admin.initUser(username)
        else:
            userEnt = user

        uidNumber = userEnt.get(libuser.UIDNUMBER)[0]

        groupEnt = self.admin.initGroup(username)
        gidNumber = groupEnt.get(libuser.GIDNUMBER)[0]
        userEnt.set(libuser.GIDNUMBER, [gidNumber])

        if user == None:
            self.admin.addUser(userEnt, mkhomedir=mkhomedir)
            self.admin.addGroup(groupEnt)

            if not mkhomedir:
                self._problemFiles = []
                dlg = self._waitWindow(_("Fixing attributes on the home directory "
                                         "for %s.  This may take a few minutes.") % username)
                dlg.show_all()
                while gtk.events_pending():
                    gtk.main_iteration(False)

                os.chown("/home/%s" % username, uidNumber, gidNumber)
                os.path.walk("/home/%s" % username, self._chown, (uidNumber,
                                                                  gidNumber))

                # selinux context
                subprocess.call(['restorecon', '-R', '/home/%s' % username])

                # copy skel files
                for fname in os.listdir("/etc/skel"):
                    dst = "/home/%s/%s" % (username, fname)
                    if not os.path.exists(dst):
                        src = "/etc/skel/%s" % fname
                        if os.path.isdir(src):
                            shutil.copytree(src, dst)
                            os.path.walk(dst, self._chown, (uidNumber,
                                                            gidNumber))
                        else:
                            shutil.copy2(src, dst)
                            os.chown(dst, uidNumber, gidNumber)

                dlg.destroy()

                if len(self._problemFiles) > 0:
                    import tempfile
                    (fd, path) = tempfile.mkstemp("", "firstboot-homedir-", "/tmp")
                    fo = os.fdopen(fd, "w")

                    for f in self._problemFiles:
                        fo.write("%s\n" % f)

                    fo.close()

                    text = _("Problems were encountered fixing the attributes "
                             "on some files in the home directory for %(user)s."
                             "  Please refer to %(path)s for which files "
                             "caused the errors.") % {"user": username,
                                                      "path": path}
                    self._showErrorMessage(text)
        else:
            self.admin.modifyUser(userEnt)
            self.admin.modifyGroup(groupEnt)
            os.chown(userEnt.get(libuser.HOMEDIRECTORY)[0],
                     userEnt.get(libuser.UIDNUMBER)[0],
                     userEnt.get(libuser.GIDNUMBER)[0])

        self.admin.setpassUser(userEnt, self.passwordEntry.get_text(), 0)

        # add user to qubes, wheel and dialout group
        wheelEnt = self.admin.lookupGroupByName("wheel")
        wheelEnt.add(libuser.MEMBERNAME, username)
        self.admin.modifyGroup(wheelEnt)
        dialoutEnt = self.admin.lookupGroupByName("dialout")
        dialoutEnt.add(libuser.MEMBERNAME, username)
        self.admin.modifyGroup(dialoutEnt)
        qubesEnt = self.admin.lookupGroupByName("qubes")
        qubesEnt.add(libuser.MEMBERNAME, username)
        self.admin.modifyGroup(qubesEnt)

        return RESULT_SUCCESS

    def createScreen(self):
        self.vbox = gtk.VBox(spacing=10)

        label = gtk.Label(_("You must create a 'user' account.\n\n"
            "In practice this is used only for locking your screen (via screensaver and KDM). This account is not accessible from the "
            "network in any way, because there is no networking in the VM where the GUI runs and where you log in (this VM is called Dom0)."))

        label.set_line_wrap(True)
        label.set_alignment(0.0, 0.5)
        label.set_size_request(500, -1)

        self.usernameEntry = gtk.Entry()

        self.guessUserName = True
        self.usernameEntry.connect("changed", self.usernameEntry_changed)

        self.passwordEntry = gtk.Entry()
        self.passwordEntry.set_visibility(False)
        self.strengthLabel = StrengthMeterWithLabel()
        self.confirmEntry = gtk.Entry()
        self.confirmEntry.set_visibility(False)
        self.confirmIcon = gtk.Image()
        self.confirmIcon.set_alignment(0.0, 0.5)
        self.confirmIcon.set_from_stock(gtk.STOCK_APPLY, gtk.ICON_SIZE_BUTTON)
        # hide by default
        self.confirmIcon.set_no_show_all(True)

        self.passwordEntry.connect("changed", self.passwordEntry_changed,
                                   self.strengthLabel,
                                   self.confirmEntry, self.confirmIcon)

        self.confirmEntry.connect("changed", self.confirmEntry_changed,
                                  self.passwordEntry, self.confirmIcon)

        self.vbox.pack_start(label, False, True)

        table = gtk.Table(3, 4)
        table.set_row_spacings(6)
        table.set_col_spacings(6)

        label = gtk.Label(_("_Username:"))
        label.set_use_underline(True)
        label.set_mnemonic_widget(self.usernameEntry)
        label.set_alignment(0.0, 0.5)
        table.attach(label, 0, 1, 1, 2, gtk.FILL)
        table.attach(self.usernameEntry, 1, 2, 1, 2, gtk.SHRINK, gtk.FILL, 5)

        label = gtk.Label(_("_Password:"))
        label.set_use_underline(True)
        label.set_mnemonic_widget(self.passwordEntry)
        label.set_alignment(0.0, 0.5)
        table.attach(label, 0, 1, 2, 3, gtk.FILL)
        table.attach(self.passwordEntry, 1, 2, 2, 3, gtk.SHRINK, gtk.FILL, 5)

        label = gtk.Label(_("Confir_m Password:"))
        label.set_use_underline(True)
        label.set_mnemonic_widget(self.confirmEntry)
        label.set_alignment(0.0, 0.5)
        table.attach(label, 0, 1, 3, 4, gtk.FILL)
        table.attach(self.confirmEntry, 1, 2, 3, 4, gtk.SHRINK, gtk.FILL, 5)

        table.attach(self.strengthLabel, 2, 3, 2, 3, gtk.FILL)
        table.attach(self.confirmIcon, 2, 3, 3, 4, gtk.FILL)

        self.vbox.pack_start(table, False)

    def focus(self):
        self.usernameEntry.grab_focus()

    def initializeUI(self):
        self.usernameEntry.set_text("")
        self.passwordEntry.set_text("")
        self.confirmEntry.set_text("")

    def _waitWindow(self, text):
        # Shamelessly copied from gui.py in anaconda.
        win = gtk.Window()
        win.set_title(_("Please wait"))
        win.set_position(gtk.WIN_POS_CENTER)

        label = gtk.Label(text)

        box = gtk.Frame()
        box.set_border_width(10)
        box.add(label)
        box.set_shadow_type(gtk.SHADOW_NONE)

        win.add(box)
        win.set_default_size(-1, -1)
        return win

    def _showErrorMessage(self, text):
        dlg = gtk.MessageDialog(None, 0, gtk.MESSAGE_ERROR, gtk.BUTTONS_OK, text)
        dlg.set_position(gtk.WIN_POS_CENTER)
        dlg.set_modal(True)
        rc = dlg.run()
        dlg.destroy()
        return None

    def usernameEntry_changed(self, un_entry):
        self.guessUserName = not bool(un_entry.get_text())

    def passwordEntry_changed(self, entry, strengthLabel,
                              confirmEntry, confirmIcon):

        self.confirmEntry_changed(confirmEntry, entry, confirmIcon)

        pw = entry.get_text()
        if not pw:
            strengthLabel.set_text("")
            strengthLabel.set_fraction(0.0)
            return

        username = self.usernameEntry.get_text() or None

        pw = Password(pw, username)
        strengthLabel.set_fraction(pw.strength_frac)
        strengthLabel.set_text('%s' % pw.strength_string)

    def confirmEntry_changed(self, entry, passwordEntry, confirmIcon):
        pw = passwordEntry.get_text()
        if not pw:
            # blank icon
            confirmIcon.hide()
            return

        if pw == entry.get_text():
            confirmIcon.show()
        else:
            # blank icon
            confirmIcon.hide()