# -*- coding: utf-8 -*-

# Copyright (C) 2010-2016  RhodeCode GmbH
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License, version 3
# (only), as published by the Free Software Foundation.
#
# 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 Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# This program is dual-licensed. If you wish to learn more about the
# RhodeCode Enterprise Edition, including its added features, Support services,
# and proprietary license terms, please see https://rhodecode.com/licenses/

"""
Set of generic validators
"""

import logging
import os
import re
from collections import defaultdict

import formencode
import ipaddress
from formencode.validators import (
    UnicodeString, OneOf, Int, Number, Regex, Email, Bool, StringBoolean, Set,
    NotEmpty, IPAddress, CIDR, String, FancyValidator
)
from pylons.i18n.translation import _
from sqlalchemy.sql.expression import true
from sqlalchemy.util import OrderedSet
from webhelpers.pylonslib.secure_form import authentication_token

from rhodecode.config.routing import ADMIN_PREFIX
from rhodecode.lib.auth import HasRepoGroupPermissionAny, HasPermissionAny
from rhodecode.lib.exceptions import LdapImportError
from rhodecode.lib.utils import repo_name_slug, make_db_config
from rhodecode.lib.utils2 import safe_int, str2bool, aslist, md5
from rhodecode.lib.vcs.backends.git.repository import GitRepository
from rhodecode.lib.vcs.backends.hg.repository import MercurialRepository
from rhodecode.lib.vcs.backends.svn.repository import SubversionRepository
from rhodecode.model.db import (
    RepoGroup, Repository, UserGroup, User, ChangesetStatus, Gist)
from rhodecode.model.settings import VcsSettingsModel

# silence warnings and pylint
UnicodeString, OneOf, Int, Number, Regex, Email, Bool, StringBoolean, Set, \
    NotEmpty, IPAddress, CIDR, String, FancyValidator

log = logging.getLogger(__name__)


class _Missing(object):
    pass

Missing = _Missing()


class StateObj(object):
    """
    this is needed to translate the messages using _() in validators
    """
    _ = staticmethod(_)


def M(self, key, state=None, **kwargs):
    """
    returns string from self.message based on given key,
    passed kw params are used to substitute %(named)s params inside
    translated strings

    :param msg:
    :param state:
    """
    if state is None:
        state = StateObj()
    else:
        state._ = staticmethod(_)
    # inject validator into state object
    return self.message(key, state, **kwargs)


def UniqueList(convert=None):
    class _UniqueList(formencode.FancyValidator):
        """
        Unique List !
        """
        messages = {
            'empty': _(u'Value cannot be an empty list'),
            'missing_value': _(u'Value cannot be an empty list'),
        }

        def _to_python(self, value, state):
            ret_val = []

            def make_unique(value):
                seen = []
                return [c for c in value if not (c in seen or seen.append(c))]

            if isinstance(value, list):
                ret_val = make_unique(value)
            elif isinstance(value, set):
                ret_val = make_unique(list(value))
            elif isinstance(value, tuple):
                ret_val = make_unique(list(value))
            elif value is None:
                ret_val = []
            else:
                ret_val = [value]

            if convert:
                ret_val = map(convert, ret_val)
            return ret_val

        def empty_value(self, value):
            return []

    return _UniqueList


def UniqueListFromString():
    class _UniqueListFromString(UniqueList()):
        def _to_python(self, value, state):
            if isinstance(value, basestring):
                value = aslist(value, ',')
            return super(_UniqueListFromString, self)._to_python(value, state)
    return _UniqueListFromString


def ValidSvnPattern(section, repo_name=None):
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'pattern_exists': _(u'Pattern already exists'),
        }

        def validate_python(self, value, state):
            if not value:
                return
            model = VcsSettingsModel(repo=repo_name)
            ui_settings = model.get_svn_patterns(section=section)
            for entry in ui_settings:
                if value == entry.value:
                    msg = M(self, 'pattern_exists', state)
                    raise formencode.Invalid(msg, value, state)
    return _validator


def ValidUsername(edit=False, old_data={}):
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'username_exists': _(u'Username "%(username)s" already exists'),
            'system_invalid_username':
                _(u'Username "%(username)s" is forbidden'),
            'invalid_username':
                _(u'Username may only contain alphanumeric characters '
                    u'underscores, periods or dashes and must begin with '
                    u'alphanumeric character or underscore')
        }

        def validate_python(self, value, state):
            if value in ['default', 'new_user']:
                msg = M(self, 'system_invalid_username', state, username=value)
                raise formencode.Invalid(msg, value, state)
            # check if user is unique
            old_un = None
            if edit:
                old_un = User.get(old_data.get('user_id')).username

            if old_un != value or not edit:
                if User.get_by_username(value, case_insensitive=True):
                    msg = M(self, 'username_exists', state, username=value)
                    raise formencode.Invalid(msg, value, state)

            if (re.match(r'^[\w]{1}[\w\-\.]{0,254}$', value)
                    is None):
                msg = M(self, 'invalid_username', state)
                raise formencode.Invalid(msg, value, state)
    return _validator


def ValidRegex(msg=None):
    class _validator(formencode.validators.Regex):
        messages = {'invalid': msg or _(u'The input is not valid')}
    return _validator


def ValidRepoUser():
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'invalid_username': _(u'Username %(username)s is not valid')
        }

        def validate_python(self, value, state):
            try:
                User.query().filter(User.active == true())\
                    .filter(User.username == value).one()
            except Exception:
                msg = M(self, 'invalid_username', state, username=value)
                raise formencode.Invalid(
                    msg, value, state, error_dict={'username': msg}
                )

    return _validator


def ValidUserGroup(edit=False, old_data={}):
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'invalid_group': _(u'Invalid user group name'),
            'group_exist': _(u'User group "%(usergroup)s" already exists'),
            'invalid_usergroup_name':
                _(u'user group name may only contain alphanumeric '
                  u'characters underscores, periods or dashes and must begin '
                  u'with alphanumeric character')
        }

        def validate_python(self, value, state):
            if value in ['default']:
                msg = M(self, 'invalid_group', state)
                raise formencode.Invalid(
                    msg, value, state, error_dict={'users_group_name': msg}
                )
            # check if group is unique
            old_ugname = None
            if edit:
                old_id = old_data.get('users_group_id')
                old_ugname = UserGroup.get(old_id).users_group_name

            if old_ugname != value or not edit:
                is_existing_group = UserGroup.get_by_group_name(
                    value, case_insensitive=True)
                if is_existing_group:
                    msg = M(self, 'group_exist', state, usergroup=value)
                    raise formencode.Invalid(
                        msg, value, state, error_dict={'users_group_name': msg}
                    )

            if re.match(r'^[a-zA-Z0-9]{1}[a-zA-Z0-9\-\_\.]+$', value) is None:
                msg = M(self, 'invalid_usergroup_name', state)
                raise formencode.Invalid(
                    msg, value, state, error_dict={'users_group_name': msg}
                )

    return _validator


def ValidRepoGroup(edit=False, old_data={}, can_create_in_root=False):
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'group_parent_id': _(u'Cannot assign this group as parent'),
            'group_exists': _(u'Group "%(group_name)s" already exists'),
            'repo_exists': _(u'Repository with name "%(group_name)s" '
                             u'already exists'),
            'permission_denied': _(u"no permission to store repository group"
                                   u"in this location"),
            'permission_denied_root': _(
                u"no permission to store repository group "
                u"in root location")
        }

        def _to_python(self, value, state):
            group_name = repo_name_slug(value.get('group_name', ''))
            group_parent_id = safe_int(value.get('group_parent_id'))
            gr = RepoGroup.get(group_parent_id)
            if gr:
                parent_group_path = gr.full_path
                # value needs to be aware of group name in order to check
                # db key This is an actual just the name to store in the
                # database
                group_name_full = (
                    parent_group_path + RepoGroup.url_sep() + group_name)
            else:
                group_name_full = group_name

            value['group_name'] = group_name
            value['group_name_full'] = group_name_full
            value['group_parent_id'] = group_parent_id
            return value

        def validate_python(self, value, state):

            old_group_name = None
            group_name = value.get('group_name')
            group_name_full = value.get('group_name_full')
            group_parent_id = safe_int(value.get('group_parent_id'))
            if group_parent_id == -1:
                group_parent_id = None

            group_obj = RepoGroup.get(old_data.get('group_id'))
            parent_group_changed = False
            if edit:
                old_group_name = group_obj.group_name
                old_group_parent_id = group_obj.group_parent_id

                if group_parent_id != old_group_parent_id:
                    parent_group_changed = True

                # TODO: mikhail: the following if statement is not reached
                # since group_parent_id's OneOf validation fails before.
                # Can be removed.

                # check against setting a parent of self
                parent_of_self = (
                    old_data['group_id'] == group_parent_id
                    if group_parent_id else False
                )
                if parent_of_self:
                    msg = M(self, 'group_parent_id', state)
                    raise formencode.Invalid(
                        msg, value, state, error_dict={'group_parent_id': msg}
                    )

            # group we're moving current group inside
            child_group = None
            if group_parent_id:
                child_group = RepoGroup.query().filter(
                    RepoGroup.group_id == group_parent_id).scalar()

            # do a special check that we cannot move a group to one of
            # it's children
            if edit and child_group:
                parents = [x.group_id for x in child_group.parents]
                move_to_children = old_data['group_id'] in parents
                if move_to_children:
                    msg = M(self, 'group_parent_id', state)
                    raise formencode.Invalid(
                        msg, value, state, error_dict={'group_parent_id': msg})

            # Check if we have permission to store in the parent.
            # Only check if the parent group changed.
            if parent_group_changed:
                if child_group is None:
                    if not can_create_in_root:
                        msg = M(self, 'permission_denied_root', state)
                        raise formencode.Invalid(
                            msg, value, state,
                            error_dict={'group_parent_id': msg})
                else:
                    valid = HasRepoGroupPermissionAny('group.admin')
                    forbidden = not valid(
                        child_group.group_name, 'can create group validator')
                    if forbidden:
                        msg = M(self, 'permission_denied', state)
                        raise formencode.Invalid(
                            msg, value, state,
                            error_dict={'group_parent_id': msg})

            # if we change the name or it's new group, check for existing names
            # or repositories with the same name
            if old_group_name != group_name_full or not edit:
                # check group
                gr = RepoGroup.get_by_group_name(group_name_full)
                if gr:
                    msg = M(self, 'group_exists', state, group_name=group_name)
                    raise formencode.Invalid(
                        msg, value, state, error_dict={'group_name': msg})

                # check for same repo
                repo = Repository.get_by_repo_name(group_name_full)
                if repo:
                    msg = M(self, 'repo_exists', state, group_name=group_name)
                    raise formencode.Invalid(
                        msg, value, state, error_dict={'group_name': msg})

    return _validator


def ValidPassword():
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'invalid_password':
                _(u'Invalid characters (non-ascii) in password')
        }

        def validate_python(self, value, state):
            try:
                (value or '').decode('ascii')
            except UnicodeError:
                msg = M(self, 'invalid_password', state)
                raise formencode.Invalid(msg, value, state,)
    return _validator


def ValidOldPassword(username):
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'invalid_password': _(u'Invalid old password')
        }

        def validate_python(self, value, state):
            from rhodecode.authentication.base import authenticate, HTTP_TYPE
            if not authenticate(username, value, '', HTTP_TYPE):
                msg = M(self, 'invalid_password', state)
                raise formencode.Invalid(
                    msg, value, state, error_dict={'current_password': msg}
                )
    return _validator


def ValidPasswordsMatch(
        passwd='new_password', passwd_confirmation='password_confirmation'):
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'password_mismatch': _(u'Passwords do not match'),
        }

        def validate_python(self, value, state):

            pass_val = value.get('password') or value.get(passwd)
            if pass_val != value[passwd_confirmation]:
                msg = M(self, 'password_mismatch', state)
                raise formencode.Invalid(
                    msg, value, state,
                    error_dict={passwd: msg, passwd_confirmation: msg}
                )
    return _validator


def ValidAuth():
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'invalid_password': _(u'invalid password'),
            'invalid_username': _(u'invalid user name'),
            'disabled_account': _(u'Your account is disabled')
        }

        def validate_python(self, value, state):
            from rhodecode.authentication.base import authenticate, HTTP_TYPE

            password = value['password']
            username = value['username']

            if not authenticate(username, password, '', HTTP_TYPE,
                                skip_missing=True):
                user = User.get_by_username(username)
                if user and not user.active:
                    log.warning('user %s is disabled', username)
                    msg = M(self, 'disabled_account', state)
                    raise formencode.Invalid(
                        msg, value, state, error_dict={'username': msg}
                    )
                else:
                    log.warning('user `%s` failed to authenticate', username)
                    msg = M(self, 'invalid_username', state)
                    msg2 = M(self, 'invalid_password', state)
                    raise formencode.Invalid(
                        msg, value, state,
                        error_dict={'username': msg, 'password': msg2}
                    )
    return _validator


def ValidAuthToken():
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'invalid_token': _(u'Token mismatch')
        }

        def validate_python(self, value, state):
            if value != authentication_token():
                msg = M(self, 'invalid_token', state)
                raise formencode.Invalid(msg, value, state)
    return _validator


def ValidRepoName(edit=False, old_data={}):
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'invalid_repo_name':
                _(u'Repository name %(repo)s is disallowed'),
            # top level
            'repository_exists': _(u'Repository with name %(repo)s '
                                   u'already exists'),
            'group_exists': _(u'Repository group with name "%(repo)s" '
                              u'already exists'),
            # inside a group
            'repository_in_group_exists': _(u'Repository with name %(repo)s '
                                            u'exists in group "%(group)s"'),
            'group_in_group_exists': _(
                u'Repository group with name "%(repo)s" '
                u'exists in group "%(group)s"'),
        }

        def _to_python(self, value, state):
            repo_name = repo_name_slug(value.get('repo_name', ''))
            repo_group = value.get('repo_group')
            if repo_group:
                gr = RepoGroup.get(repo_group)
                group_path = gr.full_path
                group_name = gr.group_name
                # value needs to be aware of group name in order to check
                # db key This is an actual just the name to store in the
                # database
                repo_name_full = group_path + RepoGroup.url_sep() + repo_name
            else:
                group_name = group_path = ''
                repo_name_full = repo_name

            value['repo_name'] = repo_name
            value['repo_name_full'] = repo_name_full
            value['group_path'] = group_path
            value['group_name'] = group_name
            return value

        def validate_python(self, value, state):

            repo_name = value.get('repo_name')
            repo_name_full = value.get('repo_name_full')
            group_path = value.get('group_path')
            group_name = value.get('group_name')

            if repo_name in [ADMIN_PREFIX, '']:
                msg = M(self, 'invalid_repo_name', state, repo=repo_name)
                raise formencode.Invalid(
                    msg, value, state, error_dict={'repo_name': msg})

            rename = old_data.get('repo_name') != repo_name_full
            create = not edit
            if rename or create:

                if group_path:
                    if Repository.get_by_repo_name(repo_name_full):
                        msg = M(self, 'repository_in_group_exists', state,
                                repo=repo_name, group=group_name)
                        raise formencode.Invalid(
                            msg, value, state, error_dict={'repo_name': msg})
                    if RepoGroup.get_by_group_name(repo_name_full):
                        msg = M(self, 'group_in_group_exists', state,
                                repo=repo_name, group=group_name)
                        raise formencode.Invalid(
                            msg, value, state, error_dict={'repo_name': msg})
                else:
                    if RepoGroup.get_by_group_name(repo_name_full):
                        msg = M(self, 'group_exists', state, repo=repo_name)
                        raise formencode.Invalid(
                            msg, value, state, error_dict={'repo_name': msg})

                    if Repository.get_by_repo_name(repo_name_full):
                        msg = M(
                            self, 'repository_exists', state, repo=repo_name)
                        raise formencode.Invalid(
                            msg, value, state, error_dict={'repo_name': msg})
            return value
    return _validator


def ValidForkName(*args, **kwargs):
    return ValidRepoName(*args, **kwargs)


def SlugifyName():
    class _validator(formencode.validators.FancyValidator):

        def _to_python(self, value, state):
            return repo_name_slug(value)

        def validate_python(self, value, state):
            pass

    return _validator


def ValidCloneUri():
    class InvalidCloneUrl(Exception):
        allowed_prefixes = ()

    def url_handler(repo_type, url):
        config = make_db_config(clear_session=False)
        if repo_type == 'hg':
            allowed_prefixes = ('http', 'svn+http', 'git+http')

            if 'http' in url[:4]:
                # initially check if it's at least the proper URL
                # or does it pass basic auth
                MercurialRepository.check_url(url, config)
            elif 'svn+http' in url[:8]:  # svn->hg import
                SubversionRepository.check_url(url, config)
            elif 'git+http' in url[:8]:  # git->hg import
                raise NotImplementedError()
            else:
                exc = InvalidCloneUrl('Clone from URI %s not allowed. '
                                      'Allowed url must start with one of %s'
                                      % (url, ','.join(allowed_prefixes)))
                exc.allowed_prefixes = allowed_prefixes
                raise exc

        elif repo_type == 'git':
            allowed_prefixes = ('http', 'svn+http', 'hg+http')
            if 'http' in url[:4]:
                # initially check if it's at least the proper URL
                # or does it pass basic auth
                GitRepository.check_url(url, config)
            elif 'svn+http' in url[:8]:  # svn->git import
                raise NotImplementedError()
            elif 'hg+http' in url[:8]:  # hg->git import
                raise NotImplementedError()
            else:
                exc = InvalidCloneUrl('Clone from URI %s not allowed. '
                                      'Allowed url must start with one of %s'
                                      % (url, ','.join(allowed_prefixes)))
                exc.allowed_prefixes = allowed_prefixes
                raise exc

    class _validator(formencode.validators.FancyValidator):
        messages = {
            'clone_uri': _(u'invalid clone url for %(rtype)s repository'),
            'invalid_clone_uri': _(
                u'Invalid clone url, provide a valid clone '
                u'url starting with one of %(allowed_prefixes)s')
        }

        def validate_python(self, value, state):
            repo_type = value.get('repo_type')
            url = value.get('clone_uri')

            if url:
                try:
                    url_handler(repo_type, url)
                except InvalidCloneUrl as e:
                    log.warning(e)
                    msg = M(self, 'invalid_clone_uri', rtype=repo_type,
                            allowed_prefixes=','.join(e.allowed_prefixes))
                    raise formencode.Invalid(msg, value, state,
                                             error_dict={'clone_uri': msg})
                except Exception:
                    log.exception('Url validation failed')
                    msg = M(self, 'clone_uri', rtype=repo_type)
                    raise formencode.Invalid(msg, value, state,
                                             error_dict={'clone_uri': msg})
    return _validator


def ValidForkType(old_data={}):
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'invalid_fork_type': _(u'Fork have to be the same type as parent')
        }

        def validate_python(self, value, state):
            if old_data['repo_type'] != value:
                msg = M(self, 'invalid_fork_type', state)
                raise formencode.Invalid(
                    msg, value, state, error_dict={'repo_type': msg}
                )
    return _validator


def CanWriteGroup(old_data=None):
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'permission_denied': _(
                u"You do not have the permission "
                u"to create repositories in this group."),
            'permission_denied_root': _(
                u"You do not have the permission to store repositories in "
                u"the root location.")
        }

        def _to_python(self, value, state):
            # root location
            if value in [-1, "-1"]:
                return None
            return value

        def validate_python(self, value, state):
            gr = RepoGroup.get(value)
            gr_name = gr.group_name if gr else None  # None means ROOT location
            # create repositories with write permission on group is set to true
            create_on_write = HasPermissionAny(
                'hg.create.write_on_repogroup.true')()
            group_admin = HasRepoGroupPermissionAny('group.admin')(
                gr_name, 'can write into group validator')
            group_write = HasRepoGroupPermissionAny('group.write')(
                gr_name, 'can write into group validator')
            forbidden = not (group_admin or (group_write and create_on_write))
            can_create_repos = HasPermissionAny(
                'hg.admin', 'hg.create.repository')
            gid = (old_data['repo_group'].get('group_id')
                   if (old_data and 'repo_group' in old_data) else None)
            value_changed = gid != safe_int(value)
            new = not old_data
            # do check if we changed the value, there's a case that someone got
            # revoked write permissions to a repository, he still created, we
            # don't need to check permission if he didn't change the value of
            # groups in form box
            if value_changed or new:
                # parent group need to be existing
                if gr and forbidden:
                    msg = M(self, 'permission_denied', state)
                    raise formencode.Invalid(
                        msg, value, state, error_dict={'repo_type': msg}
                    )
                # check if we can write to root location !
                elif gr is None and not can_create_repos():
                    msg = M(self, 'permission_denied_root', state)
                    raise formencode.Invalid(
                        msg, value, state, error_dict={'repo_type': msg}
                    )

    return _validator


def ValidPerms(type_='repo'):
    if type_ == 'repo_group':
        EMPTY_PERM = 'group.none'
    elif type_ == 'repo':
        EMPTY_PERM = 'repository.none'
    elif type_ == 'user_group':
        EMPTY_PERM = 'usergroup.none'

    class _validator(formencode.validators.FancyValidator):
        messages = {
            'perm_new_member_name':
                _(u'This username or user group name is not valid')
        }

        def _to_python(self, value, state):
            perm_updates = OrderedSet()
            perm_additions = OrderedSet()
            perm_deletions = OrderedSet()
            # build a list of permission to update/delete and new permission

            # Read the perm_new_member/perm_del_member attributes and group
            # them by they IDs
            new_perms_group = defaultdict(dict)
            del_perms_group = defaultdict(dict)
            for k, v in value.copy().iteritems():
                if k.startswith('perm_del_member'):
                    # delete from org storage so we don't process that later
                    del value[k]
                    # part is `id`, `type`
                    _type, part = k.split('perm_del_member_')
                    args = part.split('_')
                    if len(args) == 2:
                        _key, pos = args
                        del_perms_group[pos][_key] = v
                if k.startswith('perm_new_member'):
                    # delete from org storage so we don't process that later
                    del value[k]
                    # part is `id`, `type`, `perm`
                    _type, part = k.split('perm_new_member_')
                    args = part.split('_')
                    if len(args) == 2:
                        _key, pos = args
                        new_perms_group[pos][_key] = v

            # store the deletes
            for k in sorted(del_perms_group.keys()):
                perm_dict = del_perms_group[k]
                del_member = perm_dict.get('id')
                del_type = perm_dict.get('type')
                if del_member and del_type:
                    perm_deletions.add((del_member, None, del_type))

            # store additions in order of how they were added in web form
            for k in sorted(new_perms_group.keys()):
                perm_dict = new_perms_group[k]
                new_member = perm_dict.get('id')
                new_type = perm_dict.get('type')
                new_perm = perm_dict.get('perm')
                if new_member and new_perm and new_type:
                    perm_additions.add((new_member, new_perm, new_type))

            # get updates of permissions
            # (read the existing radio button states)
            for k, update_value in value.iteritems():
                if k.startswith('u_perm_') or k.startswith('g_perm_'):
                    member = k[7:]
                    update_type = {'u': 'user',
                                   'g': 'users_group'}[k[0]]
                    if member == User.DEFAULT_USER:
                        if str2bool(value.get('repo_private')):
                            # set none for default when updating to
                            # private repo protects agains form manipulation
                            update_value = EMPTY_PERM
                    perm_updates.add((member, update_value, update_type))
            # check the deletes

            value['perm_additions'] = list(perm_additions)
            value['perm_updates'] = list(perm_updates)
            value['perm_deletions'] = list(perm_deletions)

            # validate users they exist and they are active !
            for member_id, _perm, member_type in perm_additions:
                try:
                    if member_type == 'user':
                        self.user_db = User.query()\
                            .filter(User.active == true())\
                            .filter(User.user_id == member_id).one()
                    if member_type == 'users_group':
                        self.user_db = UserGroup.query()\
                            .filter(UserGroup.users_group_active == true())\
                            .filter(UserGroup.users_group_id == member_id)\
                            .one()

                except Exception:
                    log.exception('Updated permission failed: org_exc:')
                    msg = M(self, 'perm_new_member_type', state)
                    raise formencode.Invalid(
                        msg, value, state, error_dict={
                            'perm_new_member_name': msg}
                    )
            return value
    return _validator


def ValidSettings():
    class _validator(formencode.validators.FancyValidator):
        def _to_python(self, value, state):
            # settings  form for users that are not admin
            # can't edit certain parameters, it's extra backup if they mangle
            # with forms

            forbidden_params = [
                'user', 'repo_type', 'repo_enable_locking',
                'repo_enable_downloads', 'repo_enable_statistics'
            ]

            for param in forbidden_params:
                if param in value:
                    del value[param]
            return value

        def validate_python(self, value, state):
            pass
    return _validator


def ValidPath():
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'invalid_path': _(u'This is not a valid path')
        }

        def validate_python(self, value, state):
            if not os.path.isdir(value):
                msg = M(self, 'invalid_path', state)
                raise formencode.Invalid(
                    msg, value, state, error_dict={'paths_root_path': msg}
                )
    return _validator


def UniqSystemEmail(old_data={}):
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'email_taken': _(u'This e-mail address is already taken')
        }

        def _to_python(self, value, state):
            return value.lower()

        def validate_python(self, value, state):
            if (old_data.get('email') or '').lower() != value:
                user = User.get_by_email(value, case_insensitive=True)
                if user:
                    msg = M(self, 'email_taken', state)
                    raise formencode.Invalid(
                        msg, value, state, error_dict={'email': msg}
                    )
    return _validator


def ValidSystemEmail():
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'non_existing_email': _(u'e-mail "%(email)s" does not exist.')
        }

        def _to_python(self, value, state):
            return value.lower()

        def validate_python(self, value, state):
            user = User.get_by_email(value, case_insensitive=True)
            if user is None:
                msg = M(self, 'non_existing_email', state, email=value)
                raise formencode.Invalid(
                    msg, value, state, error_dict={'email': msg}
                )

    return _validator


def NotReviewedRevisions(repo_id):
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'rev_already_reviewed':
                _(u'Revisions %(revs)s are already part of pull request '
                  u'or have set status'),
        }

        def validate_python(self, value, state):
            # check revisions if they are not reviewed, or a part of another
            # pull request
            statuses = ChangesetStatus.query()\
                .filter(ChangesetStatus.revision.in_(value))\
                .filter(ChangesetStatus.repo_id == repo_id)\
                .all()

            errors = []
            for status in statuses:
                if status.pull_request_id:
                    errors.append(['pull_req', status.revision[:12]])
                elif status.status:
                    errors.append(['status', status.revision[:12]])

            if errors:
                revs = ','.join([x[1] for x in errors])
                msg = M(self, 'rev_already_reviewed', state, revs=revs)
                raise formencode.Invalid(
                    msg, value, state, error_dict={'revisions': revs})

    return _validator


def ValidIp():
    class _validator(CIDR):
        messages = {
            'badFormat': _(u'Please enter a valid IPv4 or IpV6 address'),
            'illegalBits': _(
                u'The network size (bits) must be within the range '
                u'of 0-32 (not %(bits)r)'),
        }

        # we ovveride the default to_python() call
        def to_python(self, value, state):
            v = super(_validator, self).to_python(value, state)
            v = v.strip()
            net = ipaddress.ip_network(address=v, strict=False)
            return str(net)

        def validate_python(self, value, state):
            try:
                addr = value.strip()
                # this raises an ValueError if address is not IpV4 or IpV6
                ipaddress.ip_network(addr, strict=False)
            except ValueError:
                raise formencode.Invalid(self.message('badFormat', state),
                                         value, state)

    return _validator


def FieldKey():
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'badFormat': _(
                u'Key name can only consist of letters, '
                u'underscore, dash or numbers'),
        }

        def validate_python(self, value, state):
            if not re.match('[a-zA-Z0-9_-]+$', value):
                raise formencode.Invalid(self.message('badFormat', state),
                                         value, state)
    return _validator


def BasePath():
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'badPath': _(u'Filename cannot be inside a directory'),
        }

        def _to_python(self, value, state):
            return value

        def validate_python(self, value, state):
            if value != os.path.basename(value):
                raise formencode.Invalid(self.message('badPath', state),
                                         value, state)
    return _validator


def ValidAuthPlugins():
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'import_duplicate': _(
                u'Plugins %(loaded)s and %(next_to_load)s '
                u'both export the same name'),
        }

        def _to_python(self, value, state):
            # filter empty values
            return filter(lambda s: s not in [None, ''], value)

        def validate_python(self, value, state):
            from rhodecode.authentication.base import loadplugin
            module_list = value
            unique_names = {}
            for module in module_list:
                plugin = loadplugin(module)
                if plugin is None:
                    raise formencode.Invalid(
                        _("Can't find plugin with id '{}'".format(module)),
                        value, state)
                plugin_name = plugin.name
                if plugin_name in unique_names:
                    msg = M(self, 'import_duplicate', state,
                            loaded=unique_names[plugin_name],
                            next_to_load=plugin_name)
                    raise formencode.Invalid(msg, value, state)
                unique_names[plugin_name] = plugin

    return _validator


def UniqGistId():
    class _validator(formencode.validators.FancyValidator):
        messages = {
            'gistid_taken': _(u'This gistid is already in use')
        }

        def _to_python(self, value, state):
            return repo_name_slug(value.lower())

        def validate_python(self, value, state):
            existing = Gist.get_by_access_id(value)
            if existing:
                msg = M(self, 'gistid_taken', state)
                raise formencode.Invalid(
                    msg, value, state, error_dict={'gistid': msg}
                )

    return _validator


def ValidPattern():

    class _Validator(formencode.validators.FancyValidator):

        def _to_python(self, value, state):
            patterns = []

            prefix = 'new_pattern'
            for name, v in value.iteritems():
                pattern_name = '_'.join((prefix, 'pattern'))
                if name.startswith(pattern_name):
                    new_item_id = name[len(pattern_name)+1:]

                    def _field(name):
                        return '%s_%s_%s' % (prefix, name, new_item_id)

                    values = {
                        'issuetracker_pat': value.get(_field('pattern')),
                        'issuetracker_pat': value.get(_field('pattern')),
                        'issuetracker_url': value.get(_field('url')),
                        'issuetracker_pref': value.get(_field('prefix')),
                        'issuetracker_desc': value.get(_field('description'))
                    }
                    new_uid = md5(values['issuetracker_pat'])

                    has_required_fields = (
                        values['issuetracker_pat']
                        and values['issuetracker_url'])

                    if has_required_fields:
                        settings = [
                            ('_'.join((key, new_uid)), values[key], 'unicode')
                            for key in values]
                        patterns.append(settings)

            value['patterns'] = patterns
            delete_patterns = value.get('uid') or []
            if not isinstance(delete_patterns, (list, tuple)):
                delete_patterns = [delete_patterns]
            value['delete_patterns'] = delete_patterns
            return value
    return _Validator