"""functions for schema / permissions (de)serialization using RQL

:organization: Logilab

:copyright: 2001-2010 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.

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

:license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses

"""

__docformat__ = "restructuredtext en"

import os

from itertools import chain

from logilab.common.shellutils import ProgressBar

from yams import schema as schemamod, buildobjs as ybo

from cubicweb.schema import CONSTRAINTS, ETYPE_NAME_MAP, VIRTUAL_RTYPES

from cubicweb.server import sqlutils

def group_mapping(cursor, interactive=True):

    """create a group mapping from an rql cursor

    A group mapping has standard group names as key (managers, owners at least)

    and the actual CWGroup entity's eid as associated value.

    In interactive mode (the default), missing groups'eid will be prompted

    from the user.

    """

    res = {}

    for eid, name in cursor.execute('Any G, N WHERE G is CWGroup, G name N',

                                    build_descr=False):

        res[name] = eid

    if not interactive:

        return res

    missing = [g for g in ('owners', 'managers', 'users', 'guests') if not g in res]

    if missing:

        print 'some native groups are missing but the following groups have been found:'

        print '\n'.join('* %s (%s)' % (n, eid) for n, eid in res.items())

        print

        print 'enter the eid of a to group to map to each missing native group'

        print 'or just type enter to skip permissions granted to a group'

        for group in missing:

            while True:

                value = raw_input('eid for group %s: ' % group).strip()

                if not value:

                    continue

                try:

                    res[group] = int(value)

                except ValueError:

                    print 'eid should be an integer'

                    continue

    return res

# schema / perms deserialization ##############################################

OLD_SCHEMA_TYPES = frozenset(('EFRDef', 'ENFRDef', 'ERType', 'EEType',

                              'EConstraintType', 'EConstraint', 'EGroup',

                              'EUser', 'ECache', 'EPermission', 'EProperty'))

def deserialize_schema(schema, session):

    """return a schema according to information stored in an rql database

    as CWRType and CWEType entities

    """

    repo = session.repo

    dbhelper = repo.system_source.dbhelper

    # 3.6 migration

    sqlcu = session.pool['system']

    sqlcu.execute("SELECT * FROM cw_CWRType WHERE cw_name='symetric'")

    if sqlcu.fetchall():

        sql = dbhelper.sql_rename_col('cw_CWRType', 'cw_symetric', 'cw_symmetric',

                                      dbhelper.TYPE_MAPPING['Boolean'], True)

        sqlcu.execute(sql)

        sqlcu.execute("UPDATE cw_CWRType SET cw_name='symmetric' WHERE cw_name='symetric'")

    sidx = {}

    permsdict = deserialize_ertype_permissions(session)

    schema.reading_from_database = True

    for eid, etype, desc in session.execute(

        'Any X, N, D WHERE X is CWEType, X name N, X description D',

        build_descr=False):

        # base types are already in the schema, skip them

        if etype in schemamod.BASE_TYPES:

            # just set the eid

            eschema = schema.eschema(etype)

            eschema.eid = eid

            sidx[eid] = eschema

            continue

        if etype in ETYPE_NAME_MAP:

            netype = ETYPE_NAME_MAP[etype]

            # can't use write rql queries at this point, use raw sql

            session.system_sql('UPDATE %(p)sCWEType SET %(p)sname=%%(n)s WHERE %(p)seid=%%(x)s'

                               % {'p': sqlutils.SQL_PREFIX},

                               {'x': eid, 'n': netype})

            session.system_sql('UPDATE entities SET type=%(n)s WHERE type=%(x)s',

                               {'x': etype, 'n': netype})

            # XXX should be donne as well on sqlite based sources

            if not etype in OLD_SCHEMA_TYPES and \

               (getattr(dbhelper, 'case_sensitive', False)

                or etype.lower() != netype.lower()):

                session.system_sql('ALTER TABLE %s%s RENAME TO %s%s' % (

                    sqlutils.SQL_PREFIX, etype, sqlutils.SQL_PREFIX, netype))

            session.commit(False)

            try:

                session.system_sql('UPDATE deleted_entities SET type=%(n)s WHERE type=%(x)s',

                                   {'x': etype, 'n': netype})

            except:

                pass

            tocleanup = [eid]

            tocleanup += (eid for eid, (eidetype, uri, extid) in repo._type_source_cache.items()

                          if etype == eidetype)

            repo.clear_caches(tocleanup)

            session.commit(False)

            etype = netype

        etype = ybo.EntityType(name=etype, description=desc, eid=eid)

        eschema = schema.add_entity_type(etype)

        sidx[eid] = eschema

        set_perms(eschema, permsdict)

    for etype, stype in session.execute(

        'Any XN, ETN WHERE X is CWEType, X name XN, X specializes ET, ET name ETN',

        build_descr=False):

        schema.eschema(etype)._specialized_type = stype

        schema.eschema(stype)._specialized_by.append(etype)

    for eid, rtype, desc, sym, il, ftc in session.execute(

        'Any X,N,D,S,I,FTC WHERE X is CWRType, X name N, X description D, '

        'X symmetric S, X inlined I, X fulltext_container FTC', build_descr=False):

        rtype = ybo.RelationType(name=rtype, description=desc,

                                 symmetric=bool(sym), inlined=bool(il),

                                 fulltext_container=ftc, eid=eid)

        rschema = schema.add_relation_type(rtype)

        sidx[eid] = rschema

    cstrsdict = deserialize_rdef_constraints(session)

    for values in session.execute(

        'Any X,SE,RT,OE,CARD,ORD,DESC,IDX,FTIDX,I18N,DFLT WHERE X is CWAttribute,'

        'X relation_type RT, X cardinality CARD, X ordernum ORD, X indexed IDX,'

        'X description DESC, X internationalizable I18N, X defaultval DFLT,'

        'X fulltextindexed FTIDX, X from_entity SE, X to_entity OE',

        build_descr=False):

        rdefeid, seid, reid, teid, card, ord, desc, idx, ftidx, i18n, default = values

        rdef = ybo.RelationDefinition(sidx[seid].type, sidx[reid].type, sidx[teid].type,

                                      cardinality=card,

                                      constraints=cstrsdict.get(rdefeid, ()),

                                      order=ord, description=desc,

                                      indexed=idx, fulltextindexed=ftidx,

                                      internationalizable=i18n,

                                      default=default, eid=rdefeid)

        rdefs = schema.add_relation_def(rdef)

        # rdefs can be None on duplicated relation definitions (e.g. symmetrics)

        if rdefs is not None:

            set_perms(rdefs, permsdict)

    for values in session.execute(

        'Any X,SE,RT,OE,CARD,ORD,DESC,C WHERE X is CWRelation, X relation_type RT,'

        'X cardinality CARD, X ordernum ORD, X description DESC, '

        'X from_entity SE, X to_entity OE, X composite C', build_descr=False):

        rdefeid, seid, reid, teid, card, ord, desc, c = values

        rdef = ybo.RelationDefinition(sidx[seid].type, sidx[reid].type, sidx[teid].type,

                                      constraints=cstrsdict.get(rdefeid, ()),

                                      cardinality=card, order=ord, description=desc,

                                      composite=c,  eid=rdefeid)

        rdefs = schema.add_relation_def(rdef)

        # rdefs can be None on duplicated relation definitions (e.g. symmetrics)

        if rdefs is not None:

            set_perms(rdefs, permsdict)

    schema.infer_specialization_rules()

    session.commit()

    schema.reading_from_database = False

def deserialize_ertype_permissions(session):

    """return sect action:groups associations for the given

    entity or relation schema with its eid, according to schema's

    permissions stored in the database as [read|add|delete|update]_permission

    relations between CWEType/CWRType and CWGroup entities

    """

    res = {}

    for action in ('read', 'add', 'update', 'delete'):

        rql = 'Any E,N WHERE G is CWGroup, G name N, E %s_permission G' % action

        for eid, gname in session.execute(rql, build_descr=False):

            res.setdefault(eid, {}).setdefault(action, []).append(gname)

        rql = ('Any E,X,EXPR,V WHERE X is RQLExpression, X expression EXPR, '

               'E %s_permission X, X mainvars V' % action)

        for eid, expreid, expr, mainvars in session.execute(rql, build_descr=False):

            # we don't know yet if it's a rql expr for an entity or a relation,

            # so append a tuple to differentiate from groups and so we'll be

            # able to instantiate it later

            res.setdefault(eid, {}).setdefault(action, []).append( (expr, mainvars, expreid) )

    return res

def set_perms(erschema, permsdict):

    """set permissions on the given erschema according to the permission

    definition dictionary as built by deserialize_ertype_permissions for a

    given erschema's eid

    """

    # reset erschema permissions here to avoid getting yams default anyway

    erschema.permissions = dict((action, ()) for action in erschema.ACTIONS)

    try:

        thispermsdict = permsdict[erschema.eid]

    except KeyError:

        return

    for action, somethings in thispermsdict.iteritems():

        # XXX cw < 3.6.1 bw compat

        if isinstance(erschema, schemamod.RelationDefinitionSchema) and erschema.final and action == 'add':

            action = 'update'

        erschema.permissions[action] = tuple(

            isinstance(p, tuple) and erschema.rql_expression(*p) or p

            for p in somethings)

def deserialize_rdef_constraints(session):

    """return the list of relation definition's constraints as instances"""

    res = {}

    for rdefeid, ceid, ct, val in session.execute(

        'Any E, X,TN,V WHERE E constrained_by X, X is CWConstraint, '

        'X cstrtype T, T name TN, X value V', build_descr=False):

        cstr = CONSTRAINTS[ct].deserialize(val)

        cstr.eid = ceid

        res.setdefault(rdefeid, []).append(cstr)

    return res

# schema / perms serialization ################################################

def serialize_schema(cursor, schema, verbose=False):

    """synchronize schema and permissions in the database according to

    current schema

    """

    quiet = os.environ.get('APYCOT_ROOT')

    if not quiet:

        _title = '-> storing the schema in the database '

        print _title,

    execute = cursor.execute

    eschemas = schema.entities()

    aller = eschemas + schema.relations()

    if not verbose and not quiet:

        pb_size = len(aller) + len(CONSTRAINTS) + len([x for x in eschemas if x.specializes()])

        pb = ProgressBar(pb_size, title=_title)

    else:

        pb = None

    rql = 'INSERT CWConstraintType X: X name %(ct)s'

    for cstrtype in CONSTRAINTS:

        if verbose:

            print rql

        execute(rql, {'ct': unicode(cstrtype)}, build_descr=False)

        if pb is not None:

            pb.update()

    groupmap = group_mapping(cursor, interactive=False)

    for ertype in aller:

        # skip eid and has_text relations

        if ertype in VIRTUAL_RTYPES:

            if pb is not None:

                pb.update()

            continue

        for rql, kwargs in erschema2rql(schema[ertype], groupmap):

            if verbose:

                print rql % kwargs

            execute(rql, kwargs, build_descr=False)

        if pb is not None:

            pb.update()

    for rql, kwargs in specialize2rql(schema):

        if verbose:

            print rql % kwargs

        execute(rql, kwargs, build_descr=False)

        if pb is not None:

            pb.update()

    if not quiet:

        print

def _ervalues(erschema):

    try:

        type_ = unicode(erschema.type)

    except UnicodeDecodeError, e:

        raise Exception("can't decode %s [was %s]" % (erschema.type, e))

    try:

        desc = unicode(erschema.description) or u''

    except UnicodeDecodeError, e:

        raise Exception("can't decode %s [was %s]" % (erschema.description, e))

    return {

        'name': type_,

        'final': erschema.final,

        'description': desc,

        }

def eschema_relations_values(eschema):

    values = _ervalues(eschema)

    relations = ['X %s %%(%s)s' % (attr, attr) for attr in sorted(values)]

    return relations, values

def rschema_relations_values(rschema):

    values = _ervalues(rschema)

    values['final'] = rschema.final

    values['symmetric'] = rschema.symmetric

    values['inlined'] = rschema.inlined

    relations = ['X %s %%(%s)s' % (attr, attr) for attr in sorted(values)]

    return relations, values

def _rdef_values(rschema, objtype, props):

    amap = {'order': 'ordernum'}

    values = {}

    for prop, default in schemamod.RelationDefinitionSchema.rproperty_defs(objtype).iteritems():

        if prop in ('eid', 'constraints', 'uid', 'infered', 'permissions'):

            continue

        value = props.get(prop, default)

        if prop in ('indexed', 'fulltextindexed', 'internationalizable'):

            value = bool(value)

        elif prop == 'ordernum':

            value = int(value)

        elif isinstance(value, str):

            value = unicode(value)

        values[amap.get(prop, prop)] = value

    return values

def nfrdef_relations_values(rschema, objtype, props):

    values = _rdef_values(rschema, objtype, props)

    relations = ['X %s %%(%s)s' % (attr, attr) for attr in sorted(values)]

    return relations, values

def frdef_relations_values(rschema, objtype, props):

    values = _rdef_values(rschema, objtype, props)

    default = values['default']

    del values['default']

    if default is not None:

        if default is False:

            default = u''

        elif not isinstance(default, unicode):

            default = unicode(default)

    values['defaultval'] = default

    relations = ['X %s %%(%s)s' % (attr, attr) for attr in sorted(values)]

    return relations, values

def __rdef2rql(genmap, rschema, subjtype=None, objtype=None, props=None,

               groupmap=None):

    if subjtype is None:

        assert objtype is None

        assert props is None

        targets = sorted(rschema.rdefs)

    else:

        assert not objtype is None

        targets = [(subjtype, objtype)]

    # relation schema

    if rschema.final:

        etype = 'CWAttribute'

    else:

        etype = 'CWRelation'

    for subjtype, objtype in targets:

        if props is None:

            _props = rschema.rdef(subjtype, objtype)

        else:

            _props = props

        # don't serialize infered relations

        if _props.get('infered'):

            continue

        gen = genmap[rschema.final]

        for rql, values in gen(rschema, subjtype, objtype, _props):

            yield rql, values

        # no groupmap means "no security insertion"

        if groupmap:

            for rql, args in _erperms2rql(_props, groupmap):

                args['st'] = str(subjtype)

                args['rt'] = str(rschema)

                args['ot'] = str(objtype)

                yield rql + 'X is %s, X from_entity ST, X to_entity OT, '\

                      'X relation_type RT, RT name %%(rt)s, ST name %%(st)s, '\

                      'OT name %%(ot)s' % etype, args