from django.utils import timezone
from rest_framework import status
from rest_framework.exceptions import ValidationError

from api.models import EsSessionStart, EsSessionStartDay
from api.models.audit_trail import AuditTrail
from api.models.audit_trail_details import AuditTrailDetails
from api.translation import __
from api.utils import log_critical_error, get_exception_detail, get_ip
from api.validator import BaseValidator
from api.views.admin.base import AdminApiBase


class SessionStartUpdate(AdminApiBase):
    def validate_request(self,request):
        rules = {
            "id": "required|array|exists:api.EsSessionStart,id",
        }

        # if need rename field, can put here
        attribute = {
            # "email": __("attr.email"),
        }
        # validate id first
        validator = BaseValidator(request.data,rules,attribute)
        error = validator.validate()
        if error:
            raise ValidationError(error)

        edit_obj = (
            EsSessionStart.objects
            .prefetch_related("essessionstartday_set")
            .filter(id__in=request.data.get("id"))
        )
        obj = edit_obj.first()

        status_code_string = ",".join(str(v) for v in EsSessionStart.STATUS_TO_CODE.values())
        rules = {
            "start_time": "nullable|time",
            "days": "nullable|array",
            "status": "nullable|in:"+status_code_string,
        }

        if request.data.get("code") and edit_obj.count() == 1 and request.data.get("code") != obj.code:
            rules['code'] = "nullable|not_exists:api.EsSessionStart,code"

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

        days = request.data.get("days", [])
        if days:
            rules = {
                "days": "required|integer|gte:0|lte:6",
            }

            for day in days:
                validator = BaseValidator({
                    "days": day
                }, rules, attribute)
                error = validator.validate()
                if error:
                    raise ValidationError(error)

        return edit_obj

    def post(self, request):
        # Validate input
        try:
            edit_obj = self.validate_request(request)

            action="session_start_update" # this is for audit log only
            old_new_data = {
                "new_data": {},
                "old_data": {},
            }
            updated = False
            update_fields = {}
            # if more than 1 role edit, ignore code
            if edit_obj.count() == 1:
                current_edit_obj = edit_obj.first()
                if "code" in request.data:
                    old_new_data.setdefault("old_data", {}).setdefault(current_edit_obj.id, {})["code"] = current_edit_obj.code
                    old_new_data.setdefault("new_data", {}).setdefault(current_edit_obj.id, {})["code"] = request.data.get("code")
                    update_fields['code'] = request.data['code']
                    updated = True

            ignore_fields = ['id','timestamp','signature','days']
            valid_fields = {f.column for f in EsSessionStart._meta.fields}
            for key, val in request.data.items():
                if key not in ignore_fields and key in valid_fields:
                    updated = True
                    match key:
                        case _:
                            # default the key will same as db column name
                            update_fields[key] = val

            if updated and update_fields:
                for obj in edit_obj:
                    for key, val in update_fields.items():
                        old_val = str(getattr(obj, key))
                        if old_val != val:
                            old_new_data.setdefault("old_data", []).setdefault(obj.id, {})[key] = str(getattr(obj, key))
                            old_new_data.setdefault("new_data", []).setdefault(obj.id, {})[key] = val

                update_fields['updated_by'] = request.user.id
                update_fields['updated_at'] = timezone.now()
                edit_obj.update(**update_fields)

            if "days" in request.data:
                days = request.data['days']
                for obj in edit_obj:
                    current_days = [str(rp.day) for rp in obj.essessionstartday_set.all()]
                    if set(days) != set(current_days):
                        updated=True
                        obj.essessionstartday_set.all().delete()
                        EsSessionStartDay.bulk_insert(obj.id, days)
                        old_new_data.setdefault("old_data", []).setdefault(obj.id, {})["day"] = current_days
                        old_new_data.setdefault("new_data", []).setdefault(obj.id, {})["day"] = days

            if old_new_data['old_data'] or old_new_data['new_data']:
                # insert audit trail and details
                # can insert the parent first, then only insert details
                audit_trail = AuditTrail.objects.create(
                    user_id=request.user.id,
                    type=self.audit_type,
                    ip_address=get_ip(request)
                )

                code = ",".join(edit_obj.values_list("code", flat=True))
                remark_param = {
                    "code":code
                }

                # 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=old_new_data['new_data'],
                    old_data=old_new_data['old_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)