# Copyright (C) 2021-2022 Wind River Systems, Inc.
#
#  Licensed under the Apache License, Version 2.0 (the "License");
#  you may not use this file except in compliance with the License.
#  You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS,
#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#  See the License for the specific language governing permissions and
#  limitations under the License.

import re
from sqlalchemy.sql.elements import ColumnElement

from o2common.views.route_exception import BadRequestException
from o2common.domain.filter import gen_orm_filter

from o2common.helper import o2logging
logger = o2logging.get_logger(__name__)


def gen_filter(obj: ColumnElement, filter_str: str):
    check_filter(obj, filter_str)
    try:
        filter_list = gen_orm_filter(obj, filter_str)
    except KeyError as e:
        raise BadRequestException(e.args[0])
    return filter_list


# The regular expressions testing example put on here
# (neq,testkey,value-1)
# (neq,testkey,value-1,value-2)
# (gt,hello,1)
# (gte,world,2)
# (lt,testlt,notint)
# (ncont,key1,v1,v_2)
# (gt,hello,1);(ncont,world,val1,val-2)
# (eq,wrong,60cba7be-e2cd-3b8c-a7ff-16e0f10573f9)
# (eq,description,value key)
def check_filter(obj: ColumnElement, filter_str: str):
    if not filter_str:
        return
    pattern = r'^(\((eq|neq|gt|lt|gte|lte){1},\w+,[\w -]+\)\;?|' +\
        r'\((in|nin|cont|ncont){1},\w*(,[\w -]*)*\)\;?)+'
    result = re.match(pattern, filter_str)
    logger.warning('filter: {} match result is {}'.format(filter_str, result))
    if not result:
        raise BadRequestException(
            'filter value formater not correct.')
    check_filter_attribute(obj, filter_str)


def check_filter_attribute(obj: ColumnElement, filter_str: str):
    filter_without_space = filter_str.replace(" ", "")
    items = filter_without_space.split(';')

    for i in items:
        if '(' in i:
            i = i.replace("(", "")
        if ')' in i:
            i = i.replace(")", "")
        filter_expr = i.split(',')
        if len(filter_expr) < 3:
            raise BadRequestException(
                'Filter {} formater not correct.'.format(i))
            continue
        # filter_op = filter_expr[0]
        filter_key = filter_expr[1]
        # filter_vals = filter_expr[2:]
        if not hasattr(obj, filter_key):
            raise BadRequestException(
                'Filter attrName {} not in the Object'.format(filter_key))