"""CubicWeb is a generic framework to quickly build applications which describes

relations between entitites.

:organization: Logilab

:copyright: 2001-2009 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.

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

:license: Library General Public License version 2 - http://www.gnu.org/licenses

"""

__docformat__ = "restructuredtext en"

from cubicweb.__pkginfo__ import version as __version__

import __builtin__

# '_' is available in builtins to mark internationalized string but should

# not be used to do the actual translation

if not hasattr(__builtin__, '_'):

    __builtin__._ = unicode

CW_SOFTWARE_ROOT = __path__[0]

import sys, os, logging

from StringIO import StringIO

from urllib import quote as urlquote, unquote as urlunquote

from logilab.common.decorators import cached

from logilab.common.logging_ext import set_log_methods

if os.environ.get('APYCOT_ROOT'):

    logging.basicConfig(level=logging.CRITICAL)

else:

    logging.basicConfig()

set_log_methods(sys.modules[__name__], logging.getLogger('cubicweb'))

# make all exceptions accessible from the package

from cubicweb._exceptions import *

# convert eid to the right type, raise ValueError if it's not a valid eid

typed_eid = int

#def log_thread(f, w, a):

#    print f.f_code.co_filename, f.f_code.co_name

#import threading

#threading.settrace(log_thread)

class Binary(StringIO):

    """customize StringIO to make sure we don't use unicode"""

    def __init__(self, buf=''):

        assert isinstance(buf, (str, buffer)), \

               "Binary objects must use raw strings, not %s" % buf.__class__

        StringIO.__init__(self, buf)

    def write(self, data):

        assert isinstance(data, (str, buffer)), \

               "Binary objects must use raw strings, not %s" % data.__class__

        StringIO.write(self, data)

class RequestSessionMixIn(object):

    """mixin class containing stuff shared by server session and web request

    """

    def __init__(self, vreg):

        self.vreg = vreg

        try:

            encoding = vreg.property_value('ui.encoding')

        except: # no vreg or property not registered

            encoding = 'utf-8'

        self.encoding = encoding

        # cache result of execution for (rql expr / eids),

        # should be emptied on commit/rollback of the server session / web

        # connection

        self.local_perm_cache = {}

    def property_value(self, key):

        if self.user:

            return self.user.property_value(key)

        return self.vreg.property_value(key)

    def etype_rset(self, etype, size=1):

        """return a fake result set for a particular entity type"""

        from cubicweb.rset import ResultSet

        rset = ResultSet([('A',)]*size, '%s X' % etype,

                         description=[(etype,)]*size)

        def get_entity(row, col=0, etype=etype, req=self, rset=rset):

            return req.vreg.etype_class(etype)(req, rset, row, col)

        rset.get_entity = get_entity

        return self.decorate_rset(rset)

    def eid_rset(self, eid, etype=None):

        """return a result set for the given eid without doing actual query

        (we have the eid, we can suppose it exists and user has access to the

        entity)

        """

        from cubicweb.rset import ResultSet

        eid = typed_eid(eid)

        if etype is None:

            etype = self.describe(eid)[0]

        rset = ResultSet([(eid,)], 'Any X WHERE X eid %(x)s', {'x': eid},

                         [(etype,)])

        return self.decorate_rset(rset)

    def empty_rset(self):

        """return a result set for the given eid without doing actual query

        (we have the eid, we can suppose it exists and user has access to the

        entity)

        """

        from cubicweb.rset import ResultSet

        return self.decorate_rset(ResultSet([], 'Any X WHERE X eid -1'))

    def entity_from_eid(self, eid, etype=None):

        try:

            return self.entity_cache(eid)

        except KeyError:

            rset = self.eid_rset(eid, etype)

            entity = rset.get_entity(0, 0)

            self.set_entity_cache(entity)

            return entity

    def entity_cache(self, eid):

        raise KeyError

    def set_entity_cache(self, entity):

        pass

    def create_entity(self, etype, *args, **kwargs):

        """add a new entity of the given type"""

        rql = 'INSERT %s X' % etype

        relations = []

        restrictions = []

        cachekey = []

        for rtype, rvar in args:

            relations.append('X %s %s' % (rtype, rvar))

            restrictions.append('%s eid %%(%s)s' % (rvar, rvar))

            cachekey.append(rvar)

        for attr in kwargs:

            if attr in cachekey:

                continue

            relations.append('X %s %%(%s)s' % (attr, attr))

        if relations:

            rql = '%s: %s' % (rql, ', '.join(relations))

        if restrictions:

            rql = '%s WHERE %s' % (rql, ', '.join(restrictions))

        return self.execute(rql, kwargs, cachekey).get_entity(0, 0)

    # url generation methods ##################################################

    def build_url(self, *args, **kwargs):

        """return an absolute URL using params dictionary key/values as URL

        parameters. Values are automatically URL quoted, and the

        publishing method to use may be specified or will be guessed.

        """

        # use *args since we don't want first argument to be "anonymous" to

        # avoid potential clash with kwargs

        assert len(args) == 1, 'only 0 or 1 non-named-argument expected'

        method = args[0]

        base_url = kwargs.pop('base_url', None)

        if base_url is None:

            base_url = self.base_url()

        if '_restpath' in kwargs:

            assert method == 'view', method

            path = kwargs.pop('_restpath')

        else:

            path = method

        if not kwargs:

            return u'%s%s' % (base_url, path)

        return u'%s%s?%s' % (base_url, path, self.build_url_params(**kwargs))

    def build_url_params(self, **kwargs):

        """return encoded params to incorporate them in an URL"""

        args = []

        for param, values in kwargs.items():

            if not isinstance(values, (list, tuple)):

                values = (values,)

            for value in values:

                args.append(u'%s=%s' % (param, self.url_quote(value)))

        return '&'.join(args)

    def url_quote(self, value, safe=''):

        """urllib.quote is not unicode safe, use this method to do the

        necessary encoding / decoding. Also it's designed to quote each

        part of a url path and so the '/' character will be encoded as well.

        """

        if isinstance(value, unicode):

            quoted = urlquote(value.encode(self.encoding), safe=safe)

            return unicode(quoted, self.encoding)

        return urlquote(str(value), safe=safe)

    def url_unquote(self, quoted):

        """returns a unicode unquoted string

        decoding is based on `self.encoding` which is the encoding

        used in `url_quote`

        """

        if isinstance(quoted, unicode):

            quoted = quoted.encode(self.encoding)

        try:

            return unicode(urlunquote(quoted), self.encoding)

        except UnicodeDecodeError: # might occurs on manually typed URLs

            return unicode(urlunquote(quoted), 'iso-8859-1')

    # session's user related methods #####################################

    @cached

    def user_data(self):

        """returns a dictionnary with this user's information"""

        userinfo = {}

        if self.is_internal_session:

            userinfo['login'] = "cubicweb"

            userinfo['name'] = "cubicweb"

            userinfo['email'] = ""

            return userinfo

        user = self.actual_session().user

        userinfo['login'] = user.login

        userinfo['name'] = user.name()

        userinfo['email'] = user.get_email()

        return userinfo

    def is_internal_session(self):

        """overrided on the server-side"""

        return False

    # abstract methods to override according to the web front-end #############

    def base_url(self):

        """return the root url of the instance"""

        raise NotImplementedError

    def decorate_rset(self, rset):

        """add vreg/req (at least) attributes to the given result set """

        raise NotImplementedError

    def describe(self, eid):

        """return a tuple (type, sourceuri, extid) for the entity with id <eid>"""

        raise NotImplementedError

# XXX 2.45 is allowing nicer entity type names, use this map for bw compat

ETYPE_NAME_MAP = {# 3.2 migration

                  'ECache': 'CWCache',

                  'EUser': 'CWUser',

                  'EGroup': 'CWGroup',

                  'EProperty': 'CWProperty',

                  'EFRDef': 'CWAttribute',

                  'ENFRDef': 'CWRelation',

                  'ERType': 'CWRType',

                  'EEType': 'CWEType',

                  'EConstraintType': 'CWConstraintType',

                  'EConstraint': 'CWConstraint',

                  'EPermission': 'CWPermission',

                   # 2.45 migration

                  'Eetype': 'CWEType',

                  'Ertype': 'CWRType',

                  'Efrdef': 'CWAttribute',

                  'Enfrdef': 'CWRelation',

                  'Econstraint': 'CWConstraint',

                  'Econstrainttype': 'CWConstraintType',

                  'Epermission': 'CWPermission',

                  'Egroup': 'CWGroup',

                  'Euser': 'CWUser',

                  'Eproperty': 'CWProperty',

                  'Emailaddress': 'EmailAddress',

                  'Rqlexpression': 'RQLExpression',

                  'Trinfo': 'TrInfo',

                  }

# XXX cubic web cube migration map

CW_MIGRATION_MAP = {'erudi': 'cubicweb',

                    'eaddressbook': 'addressbook',

                    'ebasket': 'basket',

                    'eblog': 'blog',

                    'ebook': 'book',

                    'ecomment': 'comment',

                    'ecompany': 'company',

                    'econference':  'conference',

                    'eemail': 'email',

                    'eevent': 'event',

                    'eexpense': 'expense',

                    'efile': 'file',

                    'einvoice': 'invoice',

                    'elink': 'link',

                    'emailinglist': 'mailinglist',

                    'eperson': 'person',

                    'eshopcart': 'shopcart',

                    'eskillmat': 'skillmat',

                    'etask': 'task',

                    'eworkcase': 'workcase',

                    'eworkorder': 'workorder',

                    'ezone': 'zone',

                    'i18ncontent': 'i18ncontent',

                    'svnfile': 'vcsfile',

                    'eclassschemes': 'keyword',

                    'eclassfolders': 'folder',

                    'eclasstags': 'tag',

                    'jpl': 'jpl',

                    'jplintra': 'jplintra',

                    'jplextra': 'jplextra',

                    'jplorg': 'jplorg',

                    'jplrecia': 'jplrecia',

                    'crm': 'crm',

                    'agueol': 'agueol',

                    'docaster': 'docaster',

                    'asteretud': 'asteretud',

                    }

def neg_role(role):

    if role == 'subject':

        return 'object'

    return 'subject'

def role(obj):

    try:

        return obj.role

    except AttributeError:

        return neg_role(obj.target)

def target(obj):

    try:

        return obj.target

    except AttributeError:

        return neg_role(obj.role)

def underline_title(title, car='-'):

    return title+'\n'+(car*len(title))

class CubicWebEventManager(object):

    """simple event / callback manager.

    Typical usage to register a callback::

      >>> from cubicweb import CW_EVENT_MANAGER

      >>> CW_EVENT_MANAGER.bind('after-registry-reload', mycallback)

    Typical usage to emit an event::

      >>> from cubicweb import CW_EVENT_MANAGER

      >>> CW_EVENT_MANAGER.emit('after-registry-reload')

    emit() accepts an additional context parameter that will be passed

    to the callback if specified (and only in that case)

    """

    def __init__(self):

        self.callbacks = {}

    def bind(self, event, callback, *args, **kwargs):

        self.callbacks.setdefault(event, []).append( (callback, args, kwargs) )

    def emit(self, event, context=None):

        for callback, args, kwargs in self.callbacks.get(event, ()):

            if context is None:

                callback(*args, **kwargs)

            else:

                callback(context, *args, **kwargs)

CW_EVENT_MANAGER = CubicWebEventManager()

def onevent(event):

    """decorator to ease event / callback binding

    >>> from cubicweb import onevent

    >>> @onevent('before-registry-reload')

    ... def mycallback():

    ...     print 'hello'

    ...

    >>>

    """

    def _decorator(func):

        CW_EVENT_MANAGER.bind(event, func)

        return func

    return _decorator