#!/usr/bin/perl -T
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
#
# This Source Code Form is "Incompatible With Secondary Licenses", as
# defined by the Mozilla Public License, v. 2.0.

use 5.10.1;
use strict;
use warnings;

use lib qw(. lib);

use Bugzilla;
use Bugzilla::Constants;
use Bugzilla::Util;
use Bugzilla::Error;
use Bugzilla::User;
use Bugzilla::Bug;
use Bugzilla::BugMail;
use Bugzilla::Flag;
use Bugzilla::Field;
use Bugzilla::Group;
use Bugzilla::Token;
use Bugzilla::Mailer;

my $user = Bugzilla->login(LOGIN_REQUIRED);

my $cgi       = Bugzilla->cgi;
my $template  = Bugzilla->template;
my $dbh       = Bugzilla->dbh;
my $userid    = $user->id;
my $editusers = $user->in_group('editusers');
local our $vars = {};

# Reject access if there is no sense in continuing.
$editusers || $user->can_bless() || ThrowUserError(
  "auth_failure",
  {
    group  => "editusers",
    reason => "cant_bless",
    action => "edit",
    object => "users"
  }
);

print $cgi->header();

# Common CGI params
my $action         = $cgi->param('action') || 'search';
my $otherUserID    = $cgi->param('userid');
my $otherUserLogin = $cgi->param('user');
my $token          = $cgi->param('token');

# Prefill template vars with data used in all or nearly all templates
$vars->{'editusers'} = $editusers;
mirrorListSelectionValues();

Bugzilla::Hook::process('admin_editusers_action',
  {vars => $vars, user => $user, action => $action});

###########################################################################
if ($action eq 'search') {

  # Allow to restrict the search to any group the user is allowed to bless.
  $vars->{'restrictablegroups'} = $user->bless_groups();
  $template->process('admin/users/search.html.tmpl', $vars)
    || ThrowTemplateError($template->error());

###########################################################################
}
elsif ($action eq 'list') {
  my $matchvalue    = $cgi->param('matchvalue') || '';
  my $matchstr      = trim($cgi->param('matchstr'));
  my $matchtype     = $cgi->param('matchtype');
  my $grouprestrict = $cgi->param('grouprestrict') || '0';

  # 0 = disabled only, 1 = enabled only, 2 = everyone
  my $is_enabled = $cgi->param('is_enabled') // 2;
  my $query
    = 'SELECT DISTINCT userid, login_name, realname, is_enabled, '
    . $dbh->sql_date_format('last_seen_date', '%Y-%m-%d')
    . ' AS last_seen_date '
    . 'FROM profiles';
  my @bindValues;
  my $nextCondition;
  my $visibleGroups;

  # If a group ID is given, make sure it is a valid one.
  my $group;
  if ($grouprestrict) {
    $group = new Bugzilla::Group(scalar $cgi->param('groupid'));
    $group || ThrowUserError('invalid_group_ID');
  }

  if (!$editusers && Bugzilla->params->{'usevisibilitygroups'}) {

    # Show only users in visible groups.
    $visibleGroups = $user->visible_groups_as_string();

    if ($visibleGroups) {
      $query .= qq{, user_group_map AS ugm
                         WHERE ugm.user_id = profiles.userid
                           AND ugm.isbless = 0
                           AND ugm.group_id IN ($visibleGroups)
                        };
      $nextCondition = 'AND';
    }
  }
  else {
    $visibleGroups = 1;
    if ($grouprestrict eq '1') {
      $query .= qq{, user_group_map AS ugm
                         WHERE ugm.user_id = profiles.userid
                           AND ugm.isbless = 0
                        };
      $nextCondition = 'AND';
    }
    else {
      $nextCondition = 'WHERE';
    }
  }

  if (!$visibleGroups) {
    $vars->{'users'} = {};
  }
  else {
    # Handle selection by login name, real name, or userid.
    if (defined($matchtype)) {
      $query .= " $nextCondition ";
      my $expr = "";
      if ($matchvalue eq 'userid') {
        if ($matchstr) {
          my $stored_matchstr = $matchstr;
          detaint_natural($matchstr)
            || ThrowUserError('illegal_user_id', {userid => $stored_matchstr});
        }
        $expr = "profiles.userid";
      }
      elsif ($matchvalue eq 'realname') {
        $expr = "profiles.realname";
      }
      else {
        $expr = "profiles.login_name";
      }

      if ($matchtype =~ /^(regexp|notregexp|exact)$/) {
        $matchstr ||= '.';
      }
      else {
        $matchstr = '' unless defined $matchstr;
      }

      # We can trick_taint because we use the value in a SELECT only,
      # using a placeholder.
      trick_taint($matchstr);

      if ($matchtype eq 'regexp') {
        $query .= $dbh->sql_regexp($expr, '?', 0, $dbh->quote($matchstr));
      }
      elsif ($matchtype eq 'notregexp') {
        $query .= $dbh->sql_not_regexp($expr, '?', 0, $dbh->quote($matchstr));
      }
      elsif ($matchtype eq 'exact') {
        $query .= $expr . ' = ?';
      }
      else {    # substr or unknown
        $query .= $dbh->sql_iposition('?', $expr) . ' > 0';
      }
      $nextCondition = 'AND';
      push(@bindValues, $matchstr);
    }

    # Handle selection by group.
    if ($grouprestrict eq '1') {
      my $grouplist
        = join(',', @{Bugzilla::Group->flatten_group_membership($group->id)});
      $query .= " $nextCondition ugm.group_id IN($grouplist) ";
    }

    detaint_natural($is_enabled);
    if ($is_enabled && ($is_enabled == 0 || $is_enabled == 1)) {
      $query .= " $nextCondition profiles.is_enabled = ?";
      $nextCondition = 'AND';
      push(@bindValues, $is_enabled);
    }

    $query .= ' ORDER BY profiles.login_name';

    $vars->{'users'}
      = $dbh->selectall_arrayref($query, {'Slice' => {}}, @bindValues);

  }

  if ($matchtype && $matchtype eq 'exact' && scalar(@{$vars->{'users'}}) == 1) {
    my $match_user_id = $vars->{'users'}[0]->{'userid'};
    my $match_user    = check_user($match_user_id);
    edit_processing($match_user);
  }
  else {
    $template->process('admin/users/list.html.tmpl', $vars)
      || ThrowTemplateError($template->error());
  }

###########################################################################
}
elsif ($action eq 'add') {
  $editusers
    || ThrowUserError("auth_failure",
    {group => "editusers", action => "add", object => "users"});

  $vars->{'token'} = issue_session_token('add_user');

  $template->process('admin/users/create.html.tmpl', $vars)
    || ThrowTemplateError($template->error());

###########################################################################
}
elsif ($action eq 'new') {
  $editusers
    || ThrowUserError("auth_failure",
    {group => "editusers", action => "add", object => "users"});

  check_token_data($token, 'add_user');

  # When e.g. the 'Env' auth method is used, the password field
  # is not displayed. In that case, set the password to *.
  my $password = $cgi->param('password');
  $password = '*' if !defined $password;

  my $new_user = Bugzilla::User->create({
    login_name    => scalar $cgi->param('login'),
    cryptpassword => $password,
    realname      => scalar $cgi->param('name'),
    disabledtext  => scalar $cgi->param('disabledtext'),
    disable_mail  => scalar $cgi->param('disable_mail'),
    extern_id     => scalar $cgi->param('extern_id'),
  });

  userDataToVars($new_user->id);

  delete_token($token);

  if ($cgi->param('notify_user')) {
    $vars->{'new_user'} = $new_user;
    my $message;

    $template->process('email/new-user-details.txt.tmpl', $vars, \$message)
      || ThrowTemplateError($template->error());
    MessageToMTA($message);
  }

  # We already display the updated page. We have to recreate a token now.
  $vars->{'token'}   = issue_session_token('edit_user');
  $vars->{'message'} = 'account_created';
  $template->process('admin/users/edit.html.tmpl', $vars)
    || ThrowTemplateError($template->error());

###########################################################################
}
elsif ($action eq 'edit') {
  my $otherUser = check_user($otherUserID, $otherUserLogin);
  edit_processing($otherUser);

###########################################################################
}
elsif ($action eq 'update') {
  check_token_data($token, 'edit_user');
  my $otherUser = check_user($otherUserID, $otherUserLogin);
  $otherUserID = $otherUser->id;

  # Lock tables during the check+update session.
  $dbh->bz_start_transaction();

  $editusers
    || $user->can_see_user($otherUser)
    || ThrowUserError('auth_failure',
    {reason => "not_visible", action => "modify", object => "user"});

  $vars->{'loginold'} = $otherUser->login;

  # Update groups
  my @group_ids = grep {s/group_//} keys %{Bugzilla->cgi->Vars};
  $otherUser->set_groups({set => \@group_ids});

  # Update profiles table entry; silently skip doing this if the user
  # is not authorized.
  my $changes = {};
  if ($editusers) {
    $otherUser->set_login($cgi->param('login'));
    $otherUser->set_name($cgi->param('name'));
    $otherUser->set_password($cgi->param('password')) if $cgi->param('password');
    $otherUser->set_disabledtext($cgi->param('disabledtext'));
    $otherUser->set_disable_mail($cgi->param('disable_mail'));
    $otherUser->set_extern_id($cgi->param('extern_id'))
      if defined($cgi->param('extern_id'));

    # Update bless groups
    my @bless_ids = grep {s/bless_//} keys %{Bugzilla->cgi->Vars};
    $otherUser->set_bless_groups({set => \@bless_ids});
  }
  $changes = $otherUser->update();

  $dbh->bz_commit_transaction();

  # XXX: userDataToVars may be off when editing ourselves.
  userDataToVars($otherUserID);
  delete_token($token);

  $vars->{'message'} = 'account_updated';
  $vars->{'changes'} = \%$changes;

  # We already display the updated page. We have to recreate a token now.
  $vars->{'token'} = issue_session_token('edit_user');

  $template->process('admin/users/edit.html.tmpl', $vars)
    || ThrowTemplateError($template->error());

###########################################################################
}
elsif ($action eq 'del') {
  my $otherUser = check_user($otherUserID, $otherUserLogin);
  $otherUserID = $otherUser->id;

  Bugzilla->params->{'allowuserdeletion'}
    || ThrowUserError('users_deletion_disabled');
  $editusers
    || ThrowUserError('auth_failure',
    {group => "editusers", action => "delete", object => "users"});
  $vars->{'otheruser'} = $otherUser;

  # Find other cross references.
  $vars->{'attachments'}
    = $dbh->selectrow_array(
    'SELECT COUNT(*) FROM attachments WHERE submitter_id = ?',
    undef, $otherUserID);
  $vars->{'assignee_or_qa'} = $dbh->selectrow_array(
    qq{SELECT COUNT(*)
           FROM bugs
           WHERE assigned_to = ? OR qa_contact = ?}, undef,
    ($otherUserID, $otherUserID)
  );
  $vars->{'reporter'}
    = $dbh->selectrow_array('SELECT COUNT(*) FROM bugs WHERE reporter = ?',
    undef, $otherUserID);
  $vars->{'cc'} = $dbh->selectrow_array('SELECT COUNT(*) FROM cc WHERE who = ?',
    undef, $otherUserID);
  $vars->{'bugs_activity'}
    = $dbh->selectrow_array('SELECT COUNT(*) FROM bugs_activity WHERE who = ?',
    undef, $otherUserID);
  $vars->{'component_cc'}
    = $dbh->selectrow_array('SELECT COUNT(*) FROM component_cc WHERE user_id = ?',
    undef, $otherUserID);
  $vars->{'email_setting'}
    = $dbh->selectrow_array(
    'SELECT COUNT(*) FROM email_setting WHERE user_id = ?',
    undef, $otherUserID);
  $vars->{'flags'}{'requestee'}
    = $dbh->selectrow_array('SELECT COUNT(*) FROM flags WHERE requestee_id = ?',
    undef, $otherUserID);
  $vars->{'flags'}{'setter'}
    = $dbh->selectrow_array('SELECT COUNT(*) FROM flags WHERE setter_id = ?',
    undef, $otherUserID);
  $vars->{'longdescs'}
    = $dbh->selectrow_array('SELECT COUNT(*) FROM longdescs WHERE who = ?',
    undef, $otherUserID);
  my $namedquery_ids
    = $dbh->selectcol_arrayref('SELECT id FROM namedqueries WHERE userid = ?',
    undef, $otherUserID);
  $vars->{'namedqueries'} = scalar(@$namedquery_ids);

  if (scalar(@$namedquery_ids)) {
    $vars->{'namedquery_group_map'}
      = $dbh->selectrow_array(
          'SELECT COUNT(*) FROM namedquery_group_map WHERE namedquery_id IN' . ' ('
        . join(', ', @$namedquery_ids)
        . ')');
  }
  else {
    $vars->{'namedquery_group_map'} = 0;
  }
  $vars->{'profile_setting'}
    = $dbh->selectrow_array(
    'SELECT COUNT(*) FROM profile_setting WHERE user_id = ?',
    undef, $otherUserID);
  $vars->{'profiles_activity'}
    = $dbh->selectrow_array(
    'SELECT COUNT(*) FROM profiles_activity WHERE who = ? AND userid != ?',
    undef, ($otherUserID, $otherUserID));
  $vars->{'quips'}
    = $dbh->selectrow_array('SELECT COUNT(*) FROM quips WHERE userid = ?',
    undef, $otherUserID);
  $vars->{'series'}
    = $dbh->selectrow_array('SELECT COUNT(*) FROM series WHERE creator = ?',
    undef, $otherUserID);
  $vars->{'watch'}{'watched'}
    = $dbh->selectrow_array('SELECT COUNT(*) FROM watch WHERE watched = ?',
    undef, $otherUserID);
  $vars->{'watch'}{'watcher'}
    = $dbh->selectrow_array('SELECT COUNT(*) FROM watch WHERE watcher = ?',
    undef, $otherUserID);
  $vars->{'whine_events'}
    = $dbh->selectrow_array(
    'SELECT COUNT(*) FROM whine_events WHERE owner_userid = ?',
    undef, $otherUserID);
  $vars->{'whine_schedules'} = $dbh->selectrow_array(
    qq{SELECT COUNT(distinct eventid)
           FROM whine_schedules
           WHERE mailto = ?
           AND mailto_type = ?
          }, undef, ($otherUserID, MAILTO_USER)
  );
  $vars->{'token'} = issue_session_token('delete_user');

  $template->process('admin/users/confirm-delete.html.tmpl', $vars)
    || ThrowTemplateError($template->error());

###########################################################################
}
elsif ($action eq 'delete') {
  check_token_data($token, 'delete_user');
  my $otherUser = check_user($otherUserID, $otherUserLogin);
  $otherUserID = $otherUser->id;

  # Cache for user accounts.
  my %usercache = (0 => new Bugzilla::User());
  my %updatedbugs;

  # Lock tables during the check+removal session.
  # XXX: if there was some change on these tables after the deletion
  #      confirmation checks, we may do something here we haven't warned
  #      about.
  $dbh->bz_start_transaction();

  Bugzilla->params->{'allowuserdeletion'}
    || ThrowUserError('users_deletion_disabled');
  $editusers
    || ThrowUserError('auth_failure',
    {group => "editusers", action => "delete", object => "users"});
  @{$otherUser->product_responsibilities()}
    && ThrowUserError('user_has_responsibility');

  Bugzilla->logout_user($otherUser);

  # Get the named query list so we can delete namedquery_group_map entries.
  my $namedqueries_as_string = join(
    ', ',
    @{
      $dbh->selectcol_arrayref('SELECT id FROM namedqueries WHERE userid = ?',
        undef, $otherUserID)
    }
  );

  # Get the timestamp for LogActivityEntry.
  my $timestamp = $dbh->selectrow_array('SELECT NOW()');

  # When we update a bug_activity entry, we update the bug timestamp, too.
  my $sth_set_bug_timestamp
    = $dbh->prepare('UPDATE bugs SET delta_ts = ? WHERE bug_id = ?');

  # Flags
  my $flag_ids
    = $dbh->selectcol_arrayref('SELECT id FROM flags WHERE requestee_id = ?',
    undef, $otherUserID);

  my $flags = Bugzilla::Flag->new_from_list($flag_ids);

  $dbh->do(
    'UPDATE flags SET requestee_id = NULL, modification_date = ?
              WHERE requestee_id = ?', undef, ($timestamp, $otherUserID)
  );

  # We want to remove the requestee but leave the requester alone,
  # so we have to log these changes manually.
  my %bugs;
  push(@{$bugs{$_->bug_id}->{$_->attach_id || 0}}, $_) foreach @$flags;
  foreach my $bug_id (keys %bugs) {
    foreach my $attach_id (keys %{$bugs{$bug_id}}) {
      my @old_summaries = Bugzilla::Flag->snapshot($bugs{$bug_id}->{$attach_id});
      $_->_set_requestee() foreach @{$bugs{$bug_id}->{$attach_id}};
      my @new_summaries = Bugzilla::Flag->snapshot($bugs{$bug_id}->{$attach_id});
      my ($removed, $added)
        = Bugzilla::Flag->update_activity(\@old_summaries, \@new_summaries);
      LogActivityEntry($bug_id, 'flagtypes.name', $removed, $added, $userid,
        $timestamp, undef, $attach_id);
    }
    $sth_set_bug_timestamp->execute($timestamp, $bug_id);
    $updatedbugs{$bug_id} = 1;
  }

  # Simple deletions in referred tables.
  $dbh->do('DELETE FROM email_setting WHERE user_id = ?', undef, $otherUserID);
  $dbh->do('DELETE FROM logincookies WHERE userid = ?',   undef, $otherUserID);
  $dbh->do('DELETE FROM namedqueries WHERE userid = ?',   undef, $otherUserID);
  $dbh->do('DELETE FROM namedqueries_link_in_footer WHERE user_id = ?',
    undef, $otherUserID);
  if ($namedqueries_as_string) {
    $dbh->do('DELETE FROM namedquery_group_map WHERE namedquery_id IN '
        . "($namedqueries_as_string)");
  }
  $dbh->do('DELETE FROM profile_setting WHERE user_id = ?', undef, $otherUserID);
  $dbh->do('DELETE FROM profiles_activity WHERE userid = ? OR who = ?',
    undef, ($otherUserID, $otherUserID));
  $dbh->do('DELETE FROM tokens WHERE userid = ?',          undef, $otherUserID);
  $dbh->do('DELETE FROM user_group_map WHERE user_id = ?', undef, $otherUserID);
  $dbh->do('DELETE FROM watch WHERE watcher = ? OR watched = ?',
    undef, ($otherUserID, $otherUserID));

  # Deletions in referred tables which need LogActivityEntry.
  my $buglist = $dbh->selectcol_arrayref('SELECT bug_id FROM cc WHERE who = ?',
    undef, $otherUserID);
  $dbh->do('DELETE FROM cc WHERE who = ?', undef, $otherUserID);
  foreach my $bug_id (@$buglist) {
    LogActivityEntry($bug_id, 'cc', $otherUser->login, '', $userid, $timestamp);
    $sth_set_bug_timestamp->execute($timestamp, $bug_id);
    $updatedbugs{$bug_id} = 1;
  }

  # Even more complex deletions in referred tables.
  my $id;

  # 1) Series
  my $sth_seriesid
    = $dbh->prepare('SELECT series_id FROM series WHERE creator = ?');
  my $sth_deleteSeries = $dbh->prepare('DELETE FROM series WHERE series_id = ?');
  my $sth_deleteSeriesData
    = $dbh->prepare('DELETE FROM series_data WHERE series_id = ?');

  $sth_seriesid->execute($otherUserID);
  while ($id = $sth_seriesid->fetchrow_array()) {
    $sth_deleteSeriesData->execute($id);
    $sth_deleteSeries->execute($id);
  }

  # 2) Whines
  my $sth_whineidFromEvents
    = $dbh->prepare('SELECT id FROM whine_events WHERE owner_userid = ?');
  my $sth_deleteWhineEvent
    = $dbh->prepare('DELETE FROM whine_events WHERE id = ?');
  my $sth_deleteWhineQuery
    = $dbh->prepare('DELETE FROM whine_queries WHERE eventid = ?');
  my $sth_deleteWhineSchedule
    = $dbh->prepare('DELETE FROM whine_schedules WHERE eventid = ?');

  $dbh->do('DELETE FROM whine_schedules WHERE mailto = ? AND mailto_type = ?',
    undef, ($otherUserID, MAILTO_USER));

  $sth_whineidFromEvents->execute($otherUserID);
  while ($id = $sth_whineidFromEvents->fetchrow_array()) {
    $sth_deleteWhineQuery->execute($id);
    $sth_deleteWhineSchedule->execute($id);
    $sth_deleteWhineEvent->execute($id);
  }

  # 3) Bugs
  # 3.1) fall back to the default assignee
  $buglist = $dbh->selectall_arrayref(
    'SELECT bug_id, initialowner
         FROM bugs
         INNER JOIN components ON components.id = bugs.component_id
         WHERE assigned_to = ?', undef, $otherUserID
  );

  my $sth_updateAssignee = $dbh->prepare(
    'UPDATE bugs SET assigned_to = ?, delta_ts = ? WHERE bug_id = ?');

  foreach my $bug (@$buglist) {
    my ($bug_id, $default_assignee_id) = @$bug;
    $sth_updateAssignee->execute($default_assignee_id, $timestamp, $bug_id);
    $updatedbugs{$bug_id} = 1;
    $default_assignee_id ||= 0;
    $usercache{$default_assignee_id} ||= new Bugzilla::User($default_assignee_id);
    LogActivityEntry($bug_id, 'assigned_to', $otherUser->login,
      $usercache{$default_assignee_id}->login,
      $userid, $timestamp);
  }

  # 3.2) fall back to the default QA contact
  $buglist = $dbh->selectall_arrayref(
    'SELECT bug_id, initialqacontact
         FROM bugs
         INNER JOIN components ON components.id = bugs.component_id
         WHERE qa_contact = ?', undef, $otherUserID
  );

  my $sth_updateQAcontact = $dbh->prepare(
    'UPDATE bugs SET qa_contact = ?, delta_ts = ? WHERE bug_id = ?');

  foreach my $bug (@$buglist) {
    my ($bug_id, $default_qa_contact_id) = @$bug;
    $sth_updateQAcontact->execute($default_qa_contact_id, $timestamp, $bug_id);
    $updatedbugs{$bug_id} = 1;
    $default_qa_contact_id ||= 0;
    $usercache{$default_qa_contact_id}
      ||= new Bugzilla::User($default_qa_contact_id);
    LogActivityEntry($bug_id, 'qa_contact', $otherUser->login,
      $usercache{$default_qa_contact_id}->login,
      $userid, $timestamp);
  }

  # Finally, remove the user account itself.
  $dbh->do('DELETE FROM profiles WHERE userid = ?', undef, $otherUserID);

  $dbh->bz_commit_transaction();
  delete_token($token);

  # It's complex to determine which items now need to be flushed from
  # memcached.  As user deletion is expected to be a rare event, we just
  # flush the entire cache when a user is deleted.
  Bugzilla->memcached->clear_all();

  $vars->{'message'}            = 'account_deleted';
  $vars->{'otheruser'}{'login'} = $otherUser->login;
  $vars->{'restrictablegroups'} = $user->bless_groups();
  $template->process('admin/users/search.html.tmpl', $vars)
    || ThrowTemplateError($template->error());

  # Send mail about what we've done to bugs.
  # The deleted user is not notified of the changes.
  foreach (keys(%updatedbugs)) {
    Bugzilla::BugMail::Send($_, {'changer' => $user});
  }

###########################################################################
}
elsif ($action eq 'activity') {
  my $otherUser = check_user($otherUserID, $otherUserLogin);

  $vars->{'profile_changes'} = $dbh->selectall_arrayref(
        "SELECT profiles.login_name AS who, "
      . $dbh->sql_date_format('profiles_activity.profiles_when')
      . " AS activity_when,
                fielddefs.name AS what,
                profiles_activity.oldvalue AS removed,
                profiles_activity.newvalue AS added
         FROM profiles_activity
         INNER JOIN profiles ON profiles_activity.who = profiles.userid
         INNER JOIN fielddefs ON fielddefs.id = profiles_activity.fieldid
         WHERE profiles_activity.userid = ?
         ORDER BY profiles_activity.profiles_when", {'Slice' => {}}, $otherUser->id
  );

  $vars->{'otheruser'} = $otherUser;

  $template->process("account/profile-activity.html.tmpl", $vars)
    || ThrowTemplateError($template->error());

###########################################################################
}
else {
  ThrowUserError('unknown_action', {action => $action});
}

exit;

###########################################################################
# Helpers
###########################################################################

# Try to build a user object using its ID, else its login name, and throw
# an error if the user does not exist.
sub check_user {
  my ($otherUserID, $otherUserLogin) = @_;

  my $otherUser;
  my $vars = {};

  if ($otherUserID) {
    $otherUser = Bugzilla::User->new($otherUserID);
    $vars->{'user_id'} = $otherUserID;
  }
  elsif ($otherUserLogin) {
    $otherUser = new Bugzilla::User({name => $otherUserLogin});
    $vars->{'user_login'} = $otherUserLogin;
  }
  ($otherUser && $otherUser->id) || ThrowUserError('invalid_user', $vars);

  return $otherUser;
}

# Copy incoming list selection values from CGI params to template variables.
sub mirrorListSelectionValues {
  my $cgi = Bugzilla->cgi;
  if (defined($cgi->param('matchtype'))) {
    foreach (
      'matchvalue',    'matchstr', 'matchtype',
      'grouprestrict', 'groupid',  'is_enabled'
      )
    {
      $vars->{'listselectionvalues'}{$_} = $cgi->param($_);
    }
  }
}

# Retrieve user data for the user editing form. User creation and user
# editing code rely on this to call derive_groups().
sub userDataToVars {
  my $otheruserid = shift;
  my $otheruser   = new Bugzilla::User($otheruserid);
  my $query;
  my $user = Bugzilla->user;
  my $dbh  = Bugzilla->dbh;

  my $grouplist = $otheruser->groups_as_string;

  $vars->{'otheruser'} = $otheruser;
  $vars->{'groups'}    = $user->bless_groups();

  $vars->{'permissions'} = $dbh->selectall_hashref(
    qq{SELECT id,
                  COUNT(directmember.group_id) AS directmember,
                  COUNT(regexpmember.group_id) AS regexpmember,
                  (CASE WHEN (groups.id IN ($grouplist)
                              AND COUNT(directmember.group_id) = 0
                              AND COUNT(regexpmember.group_id) = 0
                             ) THEN 1 ELSE 0 END) 
                      AS derivedmember,
                  COUNT(directbless.group_id) AS directbless
           FROM groups
           LEFT JOIN user_group_map AS directmember
                  ON directmember.group_id = id
                 AND directmember.user_id = ?
                 AND directmember.isbless = 0
                 AND directmember.grant_type = ?
           LEFT JOIN user_group_map AS regexpmember
                  ON regexpmember.group_id = id
                 AND regexpmember.user_id = ?
                 AND regexpmember.isbless = 0
                 AND regexpmember.grant_type = ?
           LEFT JOIN user_group_map AS directbless
                  ON directbless.group_id = id
                 AND directbless.user_id = ?
                 AND directbless.isbless = 1
                 AND directbless.grant_type = ?
          } . $dbh->sql_group_by('id'),
    'id', undef,
    (
      $otheruserid, GRANT_DIRECT, $otheruserid, GRANT_REGEXP,
      $otheruserid, GRANT_DIRECT
    )
  );

  # Find indirect bless permission.
  $query = qq{SELECT groups.id
                FROM groups, group_group_map AS ggm
                WHERE groups.id = ggm.grantor_id
                  AND ggm.member_id IN ($grouplist)
                  AND ggm.grant_type = ?
               } . $dbh->sql_group_by('id');
  foreach (@{$dbh->selectall_arrayref($query, undef, (GROUP_BLESS))}) {

    # Merge indirect bless permissions into permission variable.
    $vars->{'permissions'}{${$_}[0]}{'indirectbless'} = 1;
  }
}

sub edit_processing {
  my $otherUser = shift;
  my $user      = Bugzilla->user;
  my $template  = Bugzilla->template;

  $user->in_group('editusers')
    || $user->can_see_user($otherUser)
    || ThrowUserError('auth_failure',
    {reason => "not_visible", action => "modify", object => "user"});

  userDataToVars($otherUser->id);
  $vars->{'token'} = issue_session_token('edit_user');

  $template->process('admin/users/edit.html.tmpl', $vars)
    || ThrowTemplateError($template->error());
}