from rest_framework import status
from rest_framework.exceptions import ValidationError

from api.models import (
    EsExamActivity,
    EsExamRequirement,
    EsExamRequirementPrecedingExamination,
    EsExamRequirementSameLocation,
    EsExamRequirementSameTime,
)
from api.translation import __
from api.utils import get_exception_detail, log_critical_error
from api.validator import BaseValidator
from api.views.admin.exam_requirement_relation_grouping import related_group_ids_for_requirement
from api.views.admin.base import AdminApiBase


def _serialize_exam_activity(exam_activity):
    return {
        "id": exam_activity.id,
        "code": exam_activity.code,
        "name": exam_activity.name,
        # "exam_requirement_id": exam_activity.exam_requirement_id,
        # "exam_requirement": exam_activity.exam_requirement.name if exam_activity.exam_requirement else None,
        # "location_id": exam_activity.location_id,
        # "location": exam_activity.location.name if exam_activity.location else None,
        # "session_id": exam_activity.session_id,
        # "time_slot": exam_activity.time_slot,
        # "is_scheduled": exam_activity.is_scheduled,
    }


def _serialize_relation(relation):
    return {
        "id": relation.exam_activity.id,
        "code": relation.exam_activity.code,
        "name": relation.exam_activity.name,
    }


class ExamRequirementDeliveryInfo(AdminApiBase):
    def validate_request(self, request):
        rules = {
            "exam_requirement_id": "required|integer|exists:api.EsExamRequirement,id",
        }

        attribute = {
            "exam_requirement_id": __("attr.exam_requirement_id"),
        }

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

    def post(self, request):
        try:
            self.api_log_skip_outgoing_data = True
            self.validate_request(request)

            exam_requirement_id = request.data.get("exam_requirement_id")

            exam_requirement = (
                EsExamRequirement.objects
                .select_related("exam_period")
                .filter(id=exam_requirement_id)
                .first()
            )

            if not exam_requirement:
                return self.api_response(error=__("validation.exam_requirement_not_found", value=exam_requirement_id), code=status.HTTP_404_NOT_FOUND)

            exam_activities = (
                EsExamActivity.objects
                .select_related("exam_requirement", "location", "session")
                .filter(exam_requirement_id=exam_requirement_id)
                .order_by("name", "id")
            )

            same_time_group_ids = related_group_ids_for_requirement(
                EsExamRequirementSameTime,
                exam_requirement_id,
            )
            same_time_records = (
                EsExamRequirementSameTime.objects
                .select_related("exam_requirement", "exam_activity__exam_requirement", "exam_activity__location", "exam_activity__session")
                .filter(group_id__in=same_time_group_ids)
                .order_by("id")
            )

            same_location_group_ids = related_group_ids_for_requirement(
                EsExamRequirementSameLocation,
                exam_requirement_id,
            )
            same_location_records = (
                EsExamRequirementSameLocation.objects
                .select_related("exam_requirement", "exam_activity__exam_requirement", "exam_activity__location", "exam_activity__session")
                .filter(group_id__in=same_location_group_ids)
                .order_by("id")
            )

            preceding_examination_records = (
                EsExamRequirementPrecedingExamination.objects
                .select_related("exam_requirement", "exam_activity__exam_requirement", "exam_activity__location", "exam_activity__session")
                .filter(exam_requirement_id=exam_requirement_id)
                .order_by("id")
            )

            response = {
                # "exam_requirement": {
                #     "id": exam_requirement.id,
                #     "exam_period_id": exam_requirement.exam_period_id,
                #     "exam_period": exam_requirement.exam_period.name if exam_requirement.exam_period else None,
                #     "code": exam_requirement.code,
                #     "name": exam_requirement.name,
                #     "description": exam_requirement.description,
                #     "planned_size": exam_requirement.planned_size,
                #     "writing_time": exam_requirement.writing_time,
                #     "fixed_start_date": exam_requirement.fixed_start_date,
                #     "reading_time": exam_requirement.reading_time,
                #     "fixed_start_time": exam_requirement.fixed_start_time,
                #     "location_required": exam_requirement.location_required,
                #     "exclusive_use": exam_requirement.exclusive_use,
                #     "minimum_split_size": exam_requirement.minimum_split_size,
                #     "earliest_start": exam_requirement.earliest_start,
                #     "latest_end": exam_requirement.latest_end,
                # },
                "exam_activity": [
                    _serialize_exam_activity(exam_activity)
                    for exam_activity in exam_activities
                ],
            }

            for key, records in (
                ("same_time", same_time_records),
                ("same_location", same_location_records),
                ("preceding_examination", preceding_examination_records),
            ):
                seen_exam_activity_ids = set()
                response[key] = []
                for relation in records:
                    if (
                        not relation.exam_activity
                        or relation.exam_activity_id in seen_exam_activity_ids
                        or relation.exam_activity.exam_requirement_id == exam_requirement_id
                    ):
                        continue
                    seen_exam_activity_ids.add(relation.exam_activity_id)
                    response[key].append(_serialize_relation(relation))

            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)