# copyright 2003-2014 LOGILAB S.A. (Paris, FRANCE), all rights reserved.

# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr

#

# This file is part of CubicWeb.

#

# CubicWeb is free software: you can redistribute it and/or modify it under the

# terms of the GNU Lesser General Public License as published by the Free

# Software Foundation, either version 2.1 of the License, or (at your option)

# any later version.

#

# CubicWeb 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 Lesser General Public License for more

# details.

#

# You should have received a copy of the GNU Lesser General Public License along

# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.

"""Define server side service provided by cubicweb"""

import threading

from six import text_type

from yams.schema import role_name

from cubicweb import ValidationError

from cubicweb.server import Service

from cubicweb.predicates import match_user_groups, match_kwargs

class StatsService(Service):

    """Return a dictionary containing some statistics about the repository

    resources usage.

    """

    __regid__  = 'repo_stats'

    __select__ = match_user_groups('managers', 'users')

    def call(self):

        repo = self._cw.repo # Service are repo side only.

        results = {}

        querier = repo.querier

        source = repo.system_source

        for size, maxsize, hits, misses, title in (

            (len(querier._rql_cache), repo.config['rql-cache-size'],

            querier.cache_hit, querier.cache_miss, 'rqlt_st'),

            (len(source._cache), repo.config['rql-cache-size'],

            source.cache_hit, source.cache_miss, 'sql'),

            ):

            results['%s_cache_size' % title] = {'size': size, 'maxsize': maxsize}

            results['%s_cache_hit' % title] = hits

            results['%s_cache_miss' % title] = misses

            results['%s_cache_hit_percent' % title] = (hits * 100) / (hits + misses)

        results['type_source_cache_size'] = len(repo._type_source_cache)

        results['extid_cache_size'] = len(repo._extid_cache)

        results['sql_no_cache'] = repo.system_source.no_cache

        results['nb_open_sessions'] = len(repo._sessions)

        results['nb_active_threads'] = threading.activeCount()

        looping_tasks = repo._tasks_manager._looping_tasks

        results['looping_tasks'] = [(t.name, t.interval) for t in looping_tasks]

        results['available_cnxsets'] = repo._cnxsets_pool.qsize()

        results['threads'] = [t.name for t in threading.enumerate()]

        return results

class GcStatsService(Service):

    """Return a dictionary containing some statistics about the repository

    resources usage.

    """

    __regid__  = 'repo_gc_stats'

    __select__ = match_user_groups('managers')

    def call(self, nmax=20):

        """Return a dictionary containing some statistics about the repository

        memory usage.

        This is a public method, not requiring a session id.

        nmax is the max number of (most) referenced object returned as

        the 'referenced' result

        """

        from cubicweb._gcdebug import gc_info

        from cubicweb.appobject import AppObject

        from cubicweb.rset import ResultSet

        from cubicweb.web.request import CubicWebRequestBase

        from rql.stmts import Union

        lookupclasses = (AppObject,

                         Union, ResultSet,

                         CubicWebRequestBase)

        try:

            from cubicweb.server.session import Session, InternalSession

            lookupclasses += (InternalSession, Session)

        except ImportError:

            pass  # no server part installed

        results = {}

        counters, ocounters, garbage = gc_info(lookupclasses,

                                               viewreferrersclasses=())

        values = sorted(counters.items(), key=lambda x: x[1], reverse=True)

        results['lookupclasses'] = values

        values = sorted(ocounters.items(), key=lambda x: x[1], reverse=True)[:nmax]

        results['referenced'] = values

        results['unreachable'] = garbage

        return results

class RegisterUserService(Service):

    """check if a user with the given login exists, if not create it with the

    given password. This service is designed to be used for anonymous

    registration on public web sites.

    To use it, do:

     with self.appli.repo.internal_cnx() as cnx:

        cnx.call_service('register_user',

                         login=login,

                         password=password,

                         **cwuserkwargs)

    """

    __regid__ = 'register_user'

    __select__ = Service.__select__ & match_kwargs('login', 'password')

    default_groups = ('users',)

    def call(self, login, password, email=None, groups=None, **cwuserkwargs):

        cnx = self._cw

        errmsg = cnx._('the value "%s" is already used, use another one')

        if (cnx.execute('CWUser X WHERE X login %(login)s', {'login': login},

                        build_descr=False)

            or cnx.execute('CWUser X WHERE X use_email C, C address %(login)s',

                           {'login': login}, build_descr=False)):

            qname = role_name('login', 'subject')

            raise ValidationError(None, {qname: errmsg % login})

        if isinstance(password, text_type):

            # password should *always* be utf8 encoded

            password = password.encode('UTF8')

        cwuserkwargs['login'] = login

        cwuserkwargs['upassword'] = password

        # we have to create the user

        user = cnx.create_entity('CWUser', **cwuserkwargs)

        if groups is None:

            groups = self.default_groups

        assert groups, "CWUsers must belong to at least one CWGroup"

        group_names = ', '.join('%r' % group for group in groups)

        cnx.execute('SET X in_group G WHERE X eid %%(x)s, G name IN (%s)' % group_names,

                    {'x': user.eid})

        if email or '@' in login:

            d = {'login': login, 'email': email or login}

            if cnx.execute('EmailAddress X WHERE X address %(email)s', d,

                           build_descr=False):

                qname = role_name('address', 'subject')

                raise ValidationError(None, {qname: errmsg % d['email']})

            cnx.execute('INSERT EmailAddress X: X address %(email)s, '

                        'U primary_email X, U use_email X '

                        'WHERE U login %(login)s', d, build_descr=False)

        return user