from rest_framework import status
from rest_framework.exceptions import ValidationError
from django.db.models import Count

from api.models import Role
from api.translation import __
from api.utils import log_critical_error, get_exception_detail
from api.validator import BaseValidator
from api.views.admin.base import AdminApiBase

class RoleList(AdminApiBase):
    list_default_order_column = "id"

    def validate_request(self, request):
        rules = {
            "filter": "nullable",
            "page": "nullable",
            "per_page": "nullable",
            "sort_by": "nullable",
            "order_by": "nullable",
        }
        validator = BaseValidator(request.data, rules, {})
        error = validator.validate()
        if error:
            raise ValidationError(error)

    def custom_listing_filter(self, request, model):
        filters = request.data.get("filter") or {}
        
        if request.data.get("filter"):

            for key, val in filters.items():
                if val == "" or val is None:
                    continue
                match key:
                    case "color":
                        model = model.filter(color__icontains=val)
                    case "name" | "desc":
                        model = model.filter(**{f"{key}__icontains": val})
                    case "total_users_min":
                        model = model.filter(total_users__gte=val)
                    case "total_users_max":
                        model = model.filter(total_users__lte=val)
                    case "total_permissions_min":
                        model = model.filter(total_permissions__gte=val)
                    case "total_permissions_max":
                        model = model.filter(total_permissions__lte=val)
        return model

    def post(self, request):
        try:
            self.api_log_skip_outgoing_data = True
            self.validate_request(request)
            
            data_details = self.get_data(request)
            
            response = {
                "page": data_details["page"],
                "total": data_details["total"],
                "data": data_details["data"]
            }
            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)

    def get_data(self,request):
        roles = (
            Role.objects
            .prefetch_related("rolepermission_set","user_set")
            .annotate(
                total_users=Count('user', distinct=True),
                total_permissions=Count('rolepermission', distinct=True)
            )
        )

        roles = self.listing_filter(request, roles)
        roles = self.custom_listing_filter(request, roles)
        paginated_details = self.listing_pagination(request, roles)
        total = paginated_details["total"]
        paginated_data = paginated_details["paginated_data"]
        page = paginated_details["page"]

        return_data=[]

        for val in paginated_data:
            data={}
            data["id"] = val.id
            data["name"] = val.name
            data["desc"] = val.desc
            data["color"] = val.color
            data['total_users'] = val.total_users
            permissions = [rp.permission for rp in val.rolepermission_set.all()]
            data['total_permissions'] = val.total_permissions
            data['permission'] = [
                {"code": p, "name": __("permission.admin." + p)}
                for p in permissions
            ]

            return_data.append(data)

        return {
            "data": return_data,
            "total": total,
            "page": page,
        }