import logging
from functools import reduce
from typing import Any, List, Union

from django.db.models import QuerySet
from django.http import HttpRequest
from django.urls import reverse
from rest_framework.request import Request
from rest_framework import permissions
from rest_framework.decorators import permission_classes

from misc.to_int import safe_to_int
from misc.views.generic_api_view import GenericApiView
from misc.views.generic_serializer import GenericSerializer
from misc.views.generic_api_single_view import GenericApiSingleView
from misc.views.generic_filters import GenericFilters
from users.models import (
    User,
    UserAccess,
    ConnectingUserToAccess,
)


log = logging.getLogger(__name__)


@permission_classes((permissions.AllowAny,))
class ConnectingUserToAccessTableView(GenericApiView):
    """Определяет структуру и содержание ответа на запросы к данным таблицы ConnectingUserToAccess."""

    table_name = 'ConnectingUserToAccess'

    class Filters(GenericFilters):
        pass

    FIELDS_FILTERS = [
        GenericApiView.get_filter(
            filter_name='id_field',
            field_name='id',
            filer_method=Filters.generic_int_equal_filter,
        ),
        GenericApiView.get_filter(
            filter_name='transfer_date_field',
            field_name='transfer_date',
            filer_method=Filters.generic_str_contains_filter,
        ),
        GenericApiView.get_filter(
            filter_name='return_date_field',
            field_name='return_date',
            filer_method=Filters.generic_str_contains_filter,
        ),
        GenericApiView.get_filter(
            filter_name='comment_field',
            field_name='comment',
            filer_method=Filters.generic_str_contains_filter,
        ),
        GenericApiView.get_filter(
            filter_name='user_access_field',
            field_name='user_access',
            filer_method=Filters.generic_str_contains_filter,
        ),
        GenericApiView.get_filter(
            filter_name='user_field',
            field_name='user',
            filer_method=Filters.generic_str_contains_filter,
        ),
    ]

    # PERMISSIONS = {
    #     'create': 'users.crm_users_access_can_add_request',
    #     'view': 'users.crm_users_access_can_view_request',
    #     'edit': 'users.crm_users_access_can_respond_request',
    #     'delete': 'users.crm_users_access_can_delete_request',
    #     'view_all': 'users.crm_users_can_view_and_edit_all',
    # }
    PERMISSIONS = {
        'create': 'users.crm_users_can_edit_employee',
        'view': 'users.crm_users_can_view_employee',
        'edit': 'users.crm_users_can_edit_employee',
        'delete': 'users.crm_users_access_can_delete_request',
        'view_all': 'users.crm_users_can_view_and_edit_all',
    }

    def get_queryset(self, context: dict, user: 'UserAccess') -> QuerySet:
        """Возвращает базовый (до фильтрации и пагинации) QuerySet для таблицы."""

        user_id = context.get('user_id_field', -1)

        return ConnectingUserToAccess.objects.filter(user__id=user_id)

    def get_filtered_table_fields(self, table_fields: list, request: Union[HttpRequest, Request]) -> list:
        """Метод определяющий логику отсеивания полей таблицы."""

        excluded_fields = []

        if not request.user.has_perm(self.PERMISSIONS.get('view_all')):
            excluded_fields += ['delete_btn_field', ]

        return GenericSerializer.get_fields_without_excluded(
            serializer_fields=table_fields, excluded_fields=excluded_fields
        )

    @classmethod
    def get_actions(cls) -> list:
        """Возвращает список со списком действий, применимый к набору данных. """

        actions = [
            cls.get_action(
                name='edit',
                verbose='Сохранить изменения',
                url=reverse('user_access_list'),
            ),
        ]
        return actions

    @staticmethod
    def get_field_dict(context: dict, user: User) -> dict:
        """Распаковывает ответ и возвращает словарь со значениями полей"""

        user_id_field = ConnectingUserToAccessTableView.get_unpack_value(context.get('user_field'))
        user_id_field = safe_to_int(user_id_field, -1)
        user_field = User.objects.filter(id=user_id_field).first()

        user_access_id_field = ConnectingUserToAccessTableView.get_unpack_value(context.get('user_access_field'))
        user_access_id_field = safe_to_int(user_access_id_field, -1)
        user_access_field = UserAccess.objects.filter(id=user_access_id_field).first()

        data = {
            'user': user_field,
            'user_access': user_access_field,
            'transfer_date': ConnectingUserToAccessTableView.get_unpack_value(context.get('transfer_date_field')),
            'return_date': ConnectingUserToAccessTableView.get_unpack_value(context.get('return_date_field')),
            'comment': ConnectingUserToAccessTableView.get_unpack_value(context.get('comment_field')),
        }
        return data

    def get_action_methods(self) -> dict:
        """Возвращает словарь соотношений названий действий с их методом."""

        return {
            'edit': self.edit_elements,
        }

    def get_empty_item_prefilled_fields(self, context: dict) -> dict:
        """Возвращает список предзаполненных полей для пустого элемента."""

        user_field = context.get('user_id_field')
        prefilled_fields = {'user_field': user_field}

        return prefilled_fields


@permission_classes((permissions.AllowAny,))
class ConnectingUserToAccessElementView(GenericApiSingleView):
    """
    Определяет структуру и содержание ответа на запросы к данным элемента ConnectingUserToAccess.

    В данный момент используется только для работы с методом DELETE
    """

    table_name = 'ConnectingUserToAccess'
    element_verbose = 'Доступы у сотрудника'
    table_view_model = ConnectingUserToAccessTableView

    PERMISSIONS = {
        # 'create': 'users.crm_users_can_edit_employee',
        'view': 'users.crm_users_can_view_employee',
        # 'edit': 'users.crm_users_can_edit_employee',
        'delete': 'users.crm_users_can_edit_employee',
        'view_all': 'users.crm_users_can_view_and_edit_all',
        'edit_current_user_personal_information': 'users.crm_users_edit_current_user_personal_information',
    }