from itertools import product, combinations

from django.db import transaction
from rest_framework import serializers, status
from api.models import TtUsagePreference, TtStartPreference, TtSetting, TtPos, TtPosModuleGroupModule, TtPathway, \
    TtPathwayPosModuleGroupModule, TtPosModuleGroup, TtActivity, UserSchedulingPreference, UserConstraintSetting
from api.models.audit_trail import AuditTrail
from api.models.audit_trail_details import AuditTrailDetails
from api.views.admin.base import AdminApiBase
from api.validator import BaseValidator
from api.utils import decrypt_aes_128_cbc, encrypt_aes_128_cbc, log_critical_error, get_exception_detail, \
    get_add_new_data, get_ip, bulk_sync_to_redis
from rest_framework.exceptions import ValidationError
from api.translation import __
from backend.kafka import send_request
from backend.redis_client import redis_client


class Swap(AdminApiBase):
    def validate_request(self,request):
        # FE will always send staff_ids and location_ids
        rules = {
            "activity_id": "required|exists:api.TtActivity,id",
            "staff_ids": "nullable|array|exists:api.TtStaff,id",
            "location_ids": "nullable|array|exists:api.TtLocation,id",
            # "slot": "required",
            "socket_id": "nullable",
            "constraint_breaking_mode": "nullable",
        }

        # if need rename field, can put here
        attribute = {
            # "email": __("attr.email"),
        }

        # allow empty array but not allow no param
        if "staff_ids" not in request.data:
            raise ValidationError({
                "error": __('validation.required',field=__("staff_id")),
                "errors": {"staff_ids": __("validation.required",field=__("staff_id"))}
            })

        # allow empty array but not allow no param
        if "location_ids" not in request.data:
            raise ValidationError({
                "error": __('validation.required',field=__("location_id")),
                "errors": {"location_ids": __("validation.required",field=__("location_id"))}
            })

        activity = TtActivity.objects.filter(id=request.data["activity_id"]).first()

        if not activity.scheduled:
            raise ValidationError({
                "error": __('validation.not_available_swap_for_non_scheduled_activity'),
                "errors": {"id": __("validation.not_available_swap_for_non_scheduled_activity")}
            })

        validator = BaseValidator(request.data,rules,attribute)
        error = validator.validate()
        if error:
            raise ValidationError(error)

        # custom error after basic validation

    def post(self, request):
        # Validate input
        try:
            self.validate_request(request)
            # setting_params = {
            #     "slot_per_week",
            # }
            # settings = TtSetting.get_multiple_setting(setting_params)
            # slot_per_week = int(settings["slot_per_week"])
            activity_id = request.data["activity_id"]
            action = "swap"
            method = "swap"
            activity = TtActivity.objects.filter(id=activity_id).prefetch_related("staff","location").first()
            staff_ids = request.data.get("staff_ids")
            location_ids = request.data.get("location_ids")
            slot = activity.scheduled_start_slot
            user = request.user

            kafka_topic = self.kafka_config['REQUEST_TOPIC']
            constraint_breaking_mode = 1 if request.data.get("constraint_breaking_mode") == 1 else 0
            # constraint setting
            user_constraint_setting_list = UserConstraintSetting.get_setting(user.id)
            # scheduling preference
            user_scheduling_preference_list = UserSchedulingPreference.get_setting(user.id)

            kafka_request_data = {
                "session_id": request.user.name,
                "activities": [],
                "teaching_staff": None,
                "location": None,
                "slot": slot,
                "constraint_breaking_mode": constraint_breaking_mode,
                "constraint_setting": UserConstraintSetting.kafka_group_settings_data(user_constraint_setting_list),
                "scheduling_preference": UserSchedulingPreference.kafka_group_settings_data(user_scheduling_preference_list),
            }
            kafka_request_data["activities"].append(activity_id)
            kafka_request_data["teaching_staff"] = staff_ids
            kafka_request_data["location"] = location_ids

            send_request(kafka_topic, kafka_request_data, request.data.get("socket_id"),method)

            # insert audit trail and details
            # can insert the parent first, then only insert details
            # name = activity.name

            # audit_trail = AuditTrail.objects.create(
            #     user_id=request.user.id,
            #     type=self.audit_type,
            #     ip_address=get_ip(request)
            # )
            # remark_param = {
            #     "name":name,
            # }

            # # call to a function for insert details, so in future if want change to used worker, can modify in function only
            # AuditTrailDetails.custom_insert(
            #     audit_trail=audit_trail,
            #     action=action,
            #     remark_param=remark_param,
            #     # new_data="",
            # )
            response = {

            }

            return self.api_response(data=response)
        except ValidationError as e:
            first_message = e.detail['error']
            errors = e.detail['errors']
            return self.api_response(error=first_message,errors=errors,code=status.HTTP_400_BAD_REQUEST)
        except Exception as e:
            e_details = get_exception_detail(e)
            log_critical_error(user_id=None,descr=e_details['descr'],url=e_details['url'],trace=e_details['trace'])
            return self.api_response(error=__("message.internal_server_error"),code=status.HTTP_500_INTERNAL_SERVER_ERROR)