views.py

from django.db.models import F
from django.http import Http404
from django.shortcuts import get_object_or_404
from drf_yasg.utils import swagger_auto_schema
from pydash import get
from rest_framework import status
from rest_framework.generics import RetrieveAPIView, DestroyAPIView, ListCreateAPIView, RetrieveUpdateDestroyAPIView, \
    UpdateAPIView
from rest_framework.mixins import CreateModelMixin
from rest_framework.permissions import IsAuthenticatedOrReadOnly, IsAdminUser
from rest_framework.response import Response

from core.common.constants import (
    HEAD, INCLUDE_INVERSE_MAPPINGS_PARAM, INCLUDE_RETIRED_PARAM)
from core.common.exceptions import Http409
from core.common.mixins import ListWithHeadersMixin, ConceptDictionaryMixin
from core.common.swagger_parameters import (
    q_param, limit_param, sort_desc_param, page_param, exact_match_param, sort_asc_param, verbose_param,
    include_facets_header, updated_since_param, include_inverse_mappings_param, include_retired_param,
    compress_header)
from core.common.views import SourceChildCommonBaseView, SourceChildExtrasView, \
    SourceChildExtraRetrieveUpdateDestroyView
from core.concepts.constants import PARENT_VERSION_NOT_LATEST_CANNOT_UPDATE_CONCEPT
from core.concepts.documents import ConceptDocument
from core.concepts.models import Concept, LocalizedText
from core.concepts.permissions import CanViewParentDictionary, CanEditParentDictionary
from core.concepts.search import ConceptSearch
from core.concepts.serializers import (
    ConceptDetailSerializer, ConceptListSerializer, ConceptDescriptionSerializer, ConceptNameSerializer,
    ConceptVersionDetailSerializer,
    ConceptVersionListSerializer)
from core.mappings.serializers import MappingListSerializer


class ConceptBaseView(SourceChildCommonBaseView):
    lookup_field = 'concept'
    model = Concept
    queryset = Concept.objects.filter(is_active=True)
    document_model = ConceptDocument
    facet_class = ConceptSearch
    es_fields = Concept.es_fields
    default_filters = dict(is_active=True)

    def get_detail_serializer(self, obj, data=None, files=None, partial=False):
        return ConceptDetailSerializer(obj, data, files, partial, context=dict(request=self.request))

    def get_queryset(self):
        return Concept.get_base_queryset(self.params)


class ConceptVersionListAllView(ConceptBaseView, ListWithHeadersMixin):
    permission_classes = (CanViewParentDictionary,)

    def get_serializer_class(self):
        return ConceptDetailSerializer if self.is_verbose() else ConceptListSerializer

    def get_queryset(self):
        return Concept.global_listing_queryset(
            self.get_filter_params(), self.request.user
        ).select_related(
            'parent__organization', 'parent__user',
        ).prefetch_related('names', 'descriptions')

    @swagger_auto_schema(
        manual_parameters=[
            q_param, limit_param, sort_desc_param, sort_asc_param, exact_match_param, page_param, verbose_param,
            include_retired_param, include_inverse_mappings_param, updated_since_param,
            include_facets_header, compress_header
        ]
    )
    def get(self, request, *args, **kwargs):
        return self.list(request, *args, **kwargs)


class ConceptListView(ConceptBaseView, ListWithHeadersMixin, CreateModelMixin):
    serializer_class = ConceptListSerializer

    def get_permissions(self):
        if self.request.method == 'POST':
            return [CanEditParentDictionary(), ]

        return [CanViewParentDictionary(), ]

    def get_serializer_class(self):
        if (self.request.method == 'GET' and self.is_verbose()) or self.request.method == 'POST':
            return ConceptDetailSerializer

        return ConceptListSerializer

    def get_queryset(self):
        is_latest_version = 'collection' not in self.kwargs and 'version' not in self.kwargs
        queryset = super().get_queryset()
        if is_latest_version:
            queryset = queryset.filter(is_latest_version=True)

        return queryset.select_related(
            'parent__organization', 'parent__user', 'created_by'
        ).prefetch_related('names')

    def get(self, request, *args, **kwargs):
        return self.list(request, *args, **kwargs)

    def set_parent_resource(self):
        from core.sources.models import Source
        parent_resource = None
        source = self.kwargs.pop('source', None)
        source_version = self.kwargs.pop('version', HEAD)
        if 'org' in self.kwargs:
            filters = dict(organization__mnemonic=self.kwargs['org'])
        else:
            username = self.request.user.username if self.user_is_self else self.kwargs.get('user')
            filters = dict(user__username=username)
        if source:
            parent_resource = Source.get_version(source, source_version, filters)
        self.kwargs['parent_resource'] = self.parent_resource = parent_resource

    def post(self, request, **kwargs):  # pylint: disable=unused-argument
        self.set_parent_resource()
        serializer = self.get_serializer(data={
            **request.data, 'parent_id': self.parent_resource.id, 'name': request.data.get('id', None)
        })
        if serializer.is_valid():
            self.object = serializer.save()
            if serializer.is_valid():
                headers = self.get_success_headers(serializer.data)
                serializer = ConceptDetailSerializer(self.object, context=dict(request=request))
                return Response(serializer.data, status=status.HTTP_201_CREATED, headers=headers)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)


class ConceptRetrieveUpdateDestroyView(ConceptBaseView, RetrieveAPIView, UpdateAPIView, DestroyAPIView):
    serializer_class = ConceptDetailSerializer

    def get_object(self, queryset=None):
        queryset = self.get_queryset()
        filters = dict(id=F('versioned_object_id'))
        if 'collection' in self.kwargs:
            filters = dict()
            queryset = queryset.order_by('id').distinct('id')
            uri_param = self.request.query_params.dict().get('uri')
            if uri_param:
                filters.update(Concept.get_parent_and_owner_filters_from_uri(uri_param))
            if queryset.count() > 1 and not uri_param:
                raise Http409()

        instance = queryset.filter(**filters).first()

        if not instance:
            raise Http404()

        return instance

    def get_permissions(self):
        if self.request.method in ['GET']:
            return [CanViewParentDictionary(), ]

        if self.request.method == 'DELETE' and self.is_hard_delete_requested():
            return [IsAdminUser(), ]

        return [CanEditParentDictionary(), ]

    def update(self, request, *args, **kwargs):
        self.object = self.get_object()
        partial = kwargs.pop('partial', True)
        self.parent_resource = self.object.parent

        if self.parent_resource != self.parent_resource.head:
            return Response(
                {'non_field_errors': PARENT_VERSION_NOT_LATEST_CANNOT_UPDATE_CONCEPT},
                status=status.HTTP_400_BAD_REQUEST
            )
        self.object = self.object.clone()
        serializer = self.get_serializer(self.object, data=request.data, partial=partial)
        success_status_code = status.HTTP_200_OK

        if serializer.is_valid():
            self.object = serializer.save()
            if serializer.is_valid():
                return Response(serializer.data, status=success_status_code)

        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

    def is_hard_delete_requested(self):
        return self.request.query_params.get('hardDelete', None) in ['true', True, 'True']

    def destroy(self, request, *args, **kwargs):
        concept = self.get_object()
        comment = request.data.get('update_comment', None) or request.data.get('comment', None)
        if self.is_hard_delete_requested():
            concept.delete()
            return Response(status=status.HTTP_204_NO_CONTENT)

        errors = concept.retire(request.user, comment)

        if errors:
            return Response(errors, status=status.HTTP_400_BAD_REQUEST)

        return Response(status=status.HTTP_204_NO_CONTENT)


class ConceptReactivateView(ConceptBaseView, UpdateAPIView):
    serializer_class = ConceptDetailSerializer

    def get_object(self, queryset=None):
        return get_object_or_404(self.get_queryset(), id=F('versioned_object_id'))

    def get_permissions(self):
        if self.request.method in ['GET']:
            return [CanViewParentDictionary(), ]

        return [CanEditParentDictionary(), ]

    def update(self, request, *args, **kwargs):
        concept = self.get_object()
        comment = request.data.get('update_comment', None) or request.data.get('comment', None)
        errors = concept.unretire(request.user, comment)

        if errors:
            return Response(errors, status=status.HTTP_400_BAD_REQUEST)

        return Response(status=status.HTTP_204_NO_CONTENT)


class ConceptVersionsView(ConceptBaseView, ConceptDictionaryMixin, ListWithHeadersMixin):
    permission_classes = (CanViewParentDictionary,)

    def get_queryset(self):
        return super().get_queryset().exclude(id=F('versioned_object_id'))

    def get_serializer_class(self):
        return ConceptVersionDetailSerializer if self.is_verbose() else ConceptVersionListSerializer

    def get(self, request, *args, **kwargs):
        return self.list(request, *args, **kwargs)


class ConceptMappingsView(ConceptBaseView, ListWithHeadersMixin):
    serializer_class = MappingListSerializer
    permission_classes = (CanViewParentDictionary,)

    def get_queryset(self):
        concept = super().get_queryset().first()
        include_retired = self.request.query_params.get(INCLUDE_RETIRED_PARAM, False)
        include_indirect_mappings = self.request.query_params.get(INCLUDE_INVERSE_MAPPINGS_PARAM, 'false') == 'true'
        if include_indirect_mappings:
            mappings_queryset = concept.get_bidirectional_mappings()
        else:
            mappings_queryset = concept.get_unidirectional_mappings()

        if not include_retired:
            mappings_queryset = mappings_queryset.exclude(retired=True)

        return mappings_queryset

    def get(self, request, *args, **kwargs):
        return self.list(request, *args, **kwargs)


class ConceptVersionRetrieveView(ConceptBaseView, RetrieveAPIView):
    serializer_class = ConceptVersionDetailSerializer
    permission_classes = (CanViewParentDictionary,)

    def get_object(self, queryset=None):
        instance = self.get_queryset().first()
        if not instance:
            raise Http404()
        return instance


class ConceptLabelListCreateView(ConceptBaseView, ListWithHeadersMixin, ListCreateAPIView):
    model = LocalizedText
    parent_list_attribute = None
    default_qs_sort_attr = '-created_at'

    def get_permissions(self):
        if self.request.method in ['GET', 'HEAD']:
            return [CanViewParentDictionary()]

        return [CanEditParentDictionary()]

    def get_object(self, queryset=None):
        instance = super().get_queryset().first()
        if not instance:
            raise Http404()
        return instance

    def get_queryset(self):
        if not self.parent_list_attribute:
            return None

        instance = self.get_object()
        return getattr(instance, self.parent_list_attribute).all()

    def create(self, request, **_):  # pylint: disable=arguments-differ
        serializer = self.get_serializer(data=request.data)
        if serializer.is_valid():
            instance = self.get_object()
            new_version = instance.clone()
            subject_label_attr = "cloned_{}".format(self.parent_list_attribute)
            # get the current labels from the object
            labels = getattr(new_version, subject_label_attr, [])
            # If labels are None then we would want to initialize the labels in new_version
            saved_instance = serializer.save()
            labels.append(saved_instance)
            setattr(new_version, subject_label_attr, labels)
            new_version.comment = 'Added to %s: %s.' % (self.parent_list_attribute, saved_instance.name)
            # save updated ConceptVersion into database
            errors = Concept.persist_clone(new_version, request.user)
            if errors:
                return Response(errors, status=status.HTTP_400_BAD_REQUEST)
            headers = self.get_success_headers(serializer.data)
            return Response(serializer.data, status=status.HTTP_201_CREATED, headers=headers)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)


class ConceptLabelRetrieveUpdateDestroyView(ConceptBaseView, RetrieveUpdateDestroyAPIView):
    model = LocalizedText
    parent_list_attribute = None
    permission_classes = (IsAuthenticatedOrReadOnly,)
    default_qs_sort_attr = '-created_at'

    def get_queryset(self):
        if not self.parent_list_attribute:
            return None

        instance = self.get_resource_object()
        return getattr(instance, self.parent_list_attribute).all()

    def get_resource_object(self):
        instance = super().get_queryset().first()
        if not instance:
            raise Http404()
        return instance

    def get_object(self, queryset=None):
        instance = get(self.get_resource_object(), self.parent_list_attribute).filter(id=self.kwargs['uuid']).first()
        if not instance:
            raise Http404()
        return instance

    def update(self, request, **_):  # pylint: disable=arguments-differ
        partial = True
        instance = self.get_object()
        serializer = self.get_serializer(instance, data=request.data, partial=partial)

        if serializer.is_valid():
            resource_instance = self.get_resource_object()
            new_version = resource_instance.clone()
            saved_instance = serializer.save()
            subject_label_attr = "cloned_{}".format(self.parent_list_attribute)
            labels = getattr(new_version, subject_label_attr, [])
            labels.append(saved_instance)
            setattr(new_version, subject_label_attr, labels)
            new_version.comment = 'Updated %s in %s.' % (saved_instance.name, self.parent_list_attribute)
            errors = Concept.persist_clone(new_version, request.user)
            if errors:
                return Response(errors, status=status.HTTP_400_BAD_REQUEST)
            return Response(serializer.data, status=status.HTTP_200_OK)

        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

    def delete(self, request, *args, **kwargs):
        instance = self.get_object()

        if instance:
            resource_instance = self.get_resource_object()
            new_version = resource_instance.clone()
            subject_label_attr = "cloned_{}".format(self.parent_list_attribute)
            labels = [name.clone() for name in resource_instance.names.exclude(id=instance.id)]
            setattr(new_version, subject_label_attr, labels)
            new_version.comment = 'Deleted %s in %s.' % (instance.name, self.parent_list_attribute)
            errors = Concept.persist_clone(new_version, request.user)
            if errors:
                return Response(errors, status=status.HTTP_400_BAD_REQUEST)
        return Response(status=status.HTTP_204_NO_CONTENT)


class ConceptDescriptionListCreateView(ConceptLabelListCreateView):
    serializer_class = ConceptDescriptionSerializer
    parent_list_attribute = 'descriptions'


class ConceptNameListCreateView(ConceptLabelListCreateView):
    serializer_class = ConceptNameSerializer
    parent_list_attribute = 'names'


class ConceptNameRetrieveUpdateDestroyView(ConceptLabelRetrieveUpdateDestroyView):
    parent_list_attribute = 'names'
    serializer_class = ConceptNameSerializer


class ConceptDescriptionRetrieveUpdateDestroyView(ConceptLabelRetrieveUpdateDestroyView):
    parent_list_attribute = 'descriptions'
    serializer_class = ConceptDescriptionSerializer


class ConceptExtrasView(SourceChildExtrasView, ConceptBaseView):
    serializer_class = ConceptDetailSerializer


class ConceptExtraRetrieveUpdateDestroyView(SourceChildExtraRetrieveUpdateDestroyView, ConceptBaseView):
    serializer_class = ConceptDetailSerializer
    model = Concept