renalreg/radar

from cornflake import fields, serializers
from sqlalchemy.orm import aliased

from radar.api.permissions import AdminPermission
from radar.api.serializers.consultants import ConsultantSerializer, SpecialtySerializer
from radar.api.views.generics import (
    CreateModelView,
    DestroyModelView,
    ListModelView,
    parse_args,
    RetrieveModelView,
    UpdateModelView,
)
from radar.auth.sessions import current_user
from radar.database import db
from radar.models.consultants import Consultant, GroupConsultant, Specialty
from radar.models.groups import Group, GroupPatient
from radar.models.patients import Patient
from radar.patient_search import PatientQueryBuilder


class ConsultantRequestSerializer(serializers.Serializer):
    patient = fields.IntegerField(required=False)


def filter_consultants_by_patient_id(query, patient_id):
    # Only return consultants that belong to one of the groups the patient also belongs to
    consultant_alias = aliased(Consultant)
    consultants_for_patient_query = db.session.query(consultant_alias)
    consultants_for_patient_query = consultants_for_patient_query.join(consultant_alias.group_consultants)
    consultants_for_patient_query = consultants_for_patient_query.join(GroupConsultant.group)
    consultants_for_patient_query = consultants_for_patient_query.join(Group.group_patients)
    consultants_for_patient_query = consultants_for_patient_query.filter(
        GroupPatient.patient_id == patient_id,
        Consultant.id == consultant_alias.id,
    )
    query = query.filter(consultants_for_patient_query.exists())

    # Check the user has permission to view this patient
    patient_query = PatientQueryBuilder(current_user).build()
    patient_query = patient_query.filter(Patient.id == patient_id)
    query = query.filter(patient_query.exists())

    return query


class ConsultantListView(ListModelView):
    serializer_class = ConsultantSerializer
    model_class = Consultant

    def filter_query(self, query):
        query = super(ConsultantListView, self).filter_query(query)

        args = parse_args(ConsultantRequestSerializer)

        # Only show the consultants available to a patient
        if args['patient'] is not None:
            patient_id = args['patient']
            query = filter_consultants_by_patient_id(query, patient_id)

        return query


class ConsultantCreateView(CreateModelView):
    serializer_class = ConsultantSerializer
    model_class = Consultant
    permissions = [AdminPermission]


class ConsultantRetrieveView(RetrieveModelView):
    serializer_class = ConsultantSerializer
    model_class = Consultant


class ConsultantUpdateView(UpdateModelView):
    serializer_class = ConsultantSerializer
    model_class = Consultant
    permissions = [AdminPermission]


class ConsultantDestroyView(DestroyModelView):
    serializer_class = ConsultantSerializer
    model_class = Consultant
    permissions = [AdminPermission]


class SpecialtyListView(ListModelView):
    serializer_class = SpecialtySerializer
    model_class = Specialty


def register_views(app):
    app.add_url_rule('/consultants', view_func=ConsultantListView.as_view('consultant_list'))
    app.add_url_rule('/consultants', view_func=ConsultantCreateView.as_view('consultant_create'))
    app.add_url_rule('/consultants/<id>', view_func=ConsultantRetrieveView.as_view('consultant_retrieve'))
    app.add_url_rule('/consultants/<id>', view_func=ConsultantUpdateView.as_view('consultant_update'))
    app.add_url_rule('/consultants/<id>', view_func=ConsultantDestroyView.as_view('consultant_destroy'))
    app.add_url_rule('/specialties', view_func=SpecialtyListView.as_view('specialty_list'))