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

:organization: Logilab

:copyright: 2001-2009 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 sys

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

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'):

        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

def _set_sql_prefix(prefix):

    """3.2.0 migration function: allow to unset/reset SQL_PREFIX"""

    for module in ('checkintegrity', 'migractions', 'schemahooks',

                   'sources.rql2sql', 'sources.native', 'sqlutils'):

        try:

            sys.modules['cubicweb.server.%s' % module].SQL_PREFIX = prefix

            print 'changed SQL_PREFIX for %s' % module

        except KeyError:

            pass

def _update_database(schema, sqlcu):

    """3.2.0 migration function: update database schema by adding SQL_PREFIX to

    entity type tables and columns

    """

    for etype in schema.entities():

        if etype.is_final():

            continue

        try:

            sql = 'ALTER TABLE %s RENAME TO cw_%s' % (

                etype, ETYPE_NAME_MAP.get(etype, etype))

            print sql

            sqlcu.execute(sql)

        except:

            pass

        for rschema in etype.subject_relations():

            if rschema == 'has_text':

                continue

            if rschema.is_final() or rschema.inlined:

                sql = 'ALTER TABLE cw_%s RENAME %s TO cw_%s' % (

                    etype, rschema, rschema)

                print sql

                sqlcu.execute(sql)

# 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

    sqlcu = session.pool['system']

    _3_2_migration = False

    dbhelper = repo.system_source.dbhelper

    tables = set(t.lower() for t in dbhelper.list_tables(sqlcu))

    if 'eetype' in tables:

        _3_2_migration = True

        # 3.2 migration

        _set_sql_prefix('')

        # first rename entity types whose name changed in 3.2 without adding the

        # cw_ prefix

        for etype in OLD_SCHEMA_TYPES:

            if etype.lower() in tables:

                sql = 'ALTER TABLE %s RENAME TO %s' % (etype,

                                                       ETYPE_NAME_MAP[etype])

                print sql

                sqlcu.execute(sql)

        # other table renaming done once schema has been read

    # print 'reading schema from the database...'

    index = {}

    permsdict = deserialize_ertype_permissions(session)

    schema.reading_from_database = True

    for eid, etype, desc, meta in session.execute('Any X, N, D, M WHERE '

                                                  'X is CWEType, X name N, '

                                                  'X description D, X meta M',

                                                  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

            index[eid] = eschema

            continue

        if etype in ETYPE_NAME_MAP:

            netype = ETYPE_NAME_MAP[etype]

            print 'fixing etype name from %s to %s' % (etype, netype)

            # 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, meta=meta, eid=eid)

        eschema = schema.add_entity_type(etype)

        index[eid] = eschema

        set_perms(eschema, permsdict.get(eid, {}))

    try:

        rset = session.execute('Any XN, ETN WHERE X is CWEType, X name XN, '

                               'X specializes ET, ET name ETN')

    except: # `specializes` relation not available for versions prior to 2.50

        session.rollback(False)

    else:

        for etype, stype in rset:

            eschema = schema.eschema(etype)

            seschema = schema.eschema(stype)

            eschema._specialized_type = stype

            seschema._specialized_by.append(etype)

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

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

        'X meta M, X symetric S, X inlined I', build_descr=False):

        try:

            # bw compat: fulltext_container added in 2.47

            ft_container = session.execute('Any FTC WHERE X eid %(x)s, X fulltext_container FTC',

                                           {'x': eid}).rows[0][0]

        except:

            ft_container = None

            session.rollback(False)

        rtype = ybo.RelationType(name=rtype, description=desc, meta=bool(meta),

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

                                 fulltext_container=ft_container, eid=eid)

        rschema = schema.add_relation_type(rtype)

        index[eid] = rschema

        set_perms(rschema, permsdict.get(eid, {}))

    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

        constraints = cstrsdict.get(rdefeid, ())

        frometype = index[seid].type

        rtype = index[reid].type

        toetype = index[teid].type

        rdef = ybo.RelationDefinition(frometype, rtype, toetype, cardinality=card,

                                  order=ord, description=desc,

                                  constraints=constraints,

                                  indexed=idx, fulltextindexed=ftidx,

                                  internationalizable=i18n,

                                  default=default, eid=rdefeid)

        schema.add_relation_def(rdef)

    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

        frometype = index[seid].type

        rtype = index[reid].type

        toetype = index[teid].type

        constraints = cstrsdict.get(rdefeid, ())

        rdef = ybo.RelationDefinition(frometype, rtype, toetype, cardinality=card,

                                  order=ord, description=desc,

                                  composite=c, constraints=constraints,

                                  eid=rdefeid)

        schema.add_relation_def(rdef)

    schema.infer_specialization_rules()

    if _3_2_migration:

        _update_database(schema, sqlcu)

        _set_sql_prefix('cw_')

    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

    """

    for action in erschema.ACTIONS:

        actperms = []

        for something in permsdict.get(action, ()):

            if isinstance(something, tuple):

                actperms.append(erschema.rql_expression(*something))

            else: # group name

                actperms.append(something)

        erschema.set_permissions(action, actperms)

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

    """

    print 'serializing the schema, this may take some time'

    eschemas = schema.entities()

    aller = eschemas + schema.relations()

    if not verbose:

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

        pb = ProgressBar(pb_size)

    for cstrtype in CONSTRAINTS:

        rql = 'INSERT CWConstraintType X: X name "%s"' % cstrtype

        if verbose:

            print rql

        cursor.execute(rql)

        if not verbose:

            pb.update()

    groupmap = group_mapping(cursor, interactive=False)

    for ertype in aller:

        # skip eid and has_text relations

        if ertype in ('eid', 'identity', 'has_text',):

            pb.update()

            continue

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

            if verbose:

                print rql % kwargs

            cursor.execute(rql, kwargs)

        for rql, kwargs in erperms2rql(schema[ertype], groupmap):

            if verbose:

                print rql

            cursor.execute(rql, kwargs)

        if not verbose:

            pb.update()

    for rql, kwargs in specialize2rql(schema):

        if verbose:

            print rql % kwargs

        cursor.execute(rql, kwargs)

        if not verbose:

            pb.update()

    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_,

        'meta': erschema.meta,

        'final': erschema.is_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

# XXX 2.47 migration

HAS_FULLTEXT_CONTAINER = True

def rschema_relations_values(rschema):

    values = _ervalues(rschema)

    values['final'] = rschema.is_final()

    values['symetric'] = rschema.symetric

    values['inlined'] = rschema.inlined

    if HAS_FULLTEXT_CONTAINER:

        if isinstance(rschema.fulltext_container, str):

            values['fulltext_container'] = unicode(rschema.fulltext_container)

        else:

            values['fulltext_container'] = rschema.fulltext_container

    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 rschema.rproperty_defs(objtype).iteritems():

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

            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):