# -*- coding: utf-8 -*-
"""
Tencent is pleased to support the open source community by making 蓝鲸智云PaaS平台社区版 (BlueKing PaaS Community Edition) available.
Copyright (C) 2017-2019 THL A29 Limited, a Tencent company. All rights reserved.
Licensed under the MIT License (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://opensource.org/licenses/MIT
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.
""" # noqa

from django.core.exceptions import FieldError
from django.db.models import Count


class ClassificationCountMixin(object):

    def get_choices_fields(self):
        all_fields = self.model._meta.get_fields()
        choices_fields = []
        for field in all_fields:
            if getattr(field, 'choices', None):
                choices_fields.append(field.name)
        return choices_fields

    def get_choices(self, field):
        choices_fields = self.get_choices_fields()
        if field not in choices_fields:
            raise FieldError('Unsupported filed:%s, which should be CharField with property choices')
        return getattr(self.model._meta.get_field(field), 'choices')

    def classified_count(self, conditions=None, field=None):
        queryset = self.all()
        if conditions:
            queryset = self.filter(**conditions)
        total = queryset.count()
        if field is None:
            return {'total': total, 'groups': []}

        choices = self.get_choices(field)
        queryset = queryset.values(field).annotate(value=Count(field)).order_by()
        values = {item[field]: item['value'] for item in queryset}
        groups = []
        for code, name in choices:
            groups.append({
                'code': code,
                'name': name,
                'value': values.get(code, 0)
            })
        return total, groups
