views.py

import logging

from celery_once import AlreadyQueued
from django.core.exceptions import ValidationError
from django.db import IntegrityError
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, mixins
from rest_framework.generics import (
    RetrieveAPIView, DestroyAPIView, UpdateAPIView, ListAPIView, RetrieveUpdateDestroyAPIView
)
from rest_framework.permissions import IsAuthenticated
from rest_framework.response import Response

from core.collections.constants import (
    INCLUDE_REFERENCES_PARAM, HEAD_OF_CONCEPT_ADDED_TO_COLLECTION,
    HEAD_OF_MAPPING_ADDED_TO_COLLECTION, CONCEPT_ADDED_TO_COLLECTION_FMT, MAPPING_ADDED_TO_COLLECTION_FMT,
    DELETE_FAILURE, DELETE_SUCCESS, NO_MATCH, VERSION_ALREADY_EXISTS,
    SOURCE_MAPPINGS
)
from core.collections.documents import CollectionDocument
from core.collections.models import Collection, CollectionReference
from core.collections.search import CollectionSearch
from core.collections.serializers import (
    CollectionDetailSerializer, CollectionListSerializer,
    CollectionCreateSerializer, CollectionReferenceSerializer, CollectionVersionDetailSerializer,
    CollectionVersionListSerializer)
from core.collections.utils import is_concept, is_version_specified
from core.common.constants import (
    HEAD, RELEASED_PARAM, PROCESSING_PARAM, OK_MESSAGE, NOT_FOUND, MUST_SPECIFY_EXTRA_PARAM_IN_BODY
)
from core.common.mixins import (
    ConceptDictionaryCreateMixin, ListWithHeadersMixin, ConceptDictionaryUpdateMixin,
    ConceptContainerExportMixin,
    ConceptContainerProcessingMixin)
from core.common.permissions import (
    CanViewConceptDictionary, CanEditConceptDictionary, HasAccessToVersionedObject,
    CanViewConceptDictionaryVersion
)
from core.common.swagger_parameters import q_param, compress_header, page_param, verbose_param, exact_match_param, \
    include_facets_header, sort_asc_param, sort_desc_param, updated_since_param, include_retired_param, limit_param
from core.common.tasks import add_references, export_collection
from core.common.utils import compact_dict_by_values, parse_boolean_query_param
from core.common.views import BaseAPIView, BaseLogoView

logger = logging.getLogger('oclapi')


class CollectionBaseView(BaseAPIView):
    lookup_field = 'collection'
    pk_field = 'mnemonic'
    model = Collection
    permission_classes = (CanViewConceptDictionary,)
    queryset = Collection.objects.filter(is_active=True)

    def set_parent_resource(self):
        from core.orgs.models import Organization
        from core.users.models import UserProfile
        org = self.kwargs.get('org', None)
        user = self.kwargs.get('user', None)
        if not user and self.user_is_self:
            user = self.request.user.username
        parent_resource = None
        if org:
            parent_resource = Organization.objects.filter(mnemonic=org).first()
        if user:
            parent_resource = UserProfile.objects.filter(username=user).first()

        self.kwargs['parent_resource'] = self.parent_resource = parent_resource

    def get_serializer_context(self):
        context = super().get_serializer_context()
        context.update({'request': self.request, INCLUDE_REFERENCES_PARAM: self.should_include_references()})
        return context

    @staticmethod
    def get_detail_serializer(obj):
        return CollectionDetailSerializer(obj)

    def get_filter_params(self, default_version_to_head=True):
        query_params = self.request.query_params.dict()

        version = query_params.get('version', None) or self.kwargs.get('version', None)
        if not version and default_version_to_head:
            version = HEAD

        kwargs = self.kwargs.copy()
        if self.user_is_self and self.request.user.is_authenticated:
            kwargs['user'] = self.request.user.username

        return {
            **query_params.copy(), **kwargs,
            'version': version, 'include_references': self.should_include_references()
        }

    def get_queryset(self):
        queryset = Collection.get_base_queryset(
            compact_dict_by_values(self.get_filter_params())
        ).select_related(
            'user', 'organization'
        )

        if self.is_verbose():
            queryset = queryset.select_related('created_by', 'updated_by')

        return queryset

    def should_include_references(self):
        return self.request.query_params.get(INCLUDE_REFERENCES_PARAM, 'false').lower() == 'true'


class CollectionVersionBaseView(CollectionBaseView):
    def get_filter_params(self, default_version_to_head=False):
        return super().get_filter_params(default_version_to_head)


class CollectionListView(CollectionBaseView, ConceptDictionaryCreateMixin, ListWithHeadersMixin):
    serializer_class = CollectionListSerializer
    is_searchable = True
    es_fields = {
        'collection_type': {'sortable': True, 'filterable': True, 'facet': True, 'exact': True},
        'mnemonic': {'sortable': True, 'filterable': True, 'exact': True},
        'name': {'sortable': True, 'filterable': True, 'exact': True},
        'last_update': {'sortable': True, 'filterable': True, 'default': 'desc'},
        'locale': {'sortable': False, 'filterable': True, 'facet': True},
        'owner': {'sortable': True, 'filterable': True, 'facet': True, 'exact': True},
        'owner_type': {'sortable': False, 'filterable': True, 'facet': True},
        'custom_validation_schema': {'sortable': False, 'filterable': True},
        'canonical_url': {'sortable': True, 'filterable': True},
    }
    document_model = CollectionDocument
    facet_class = CollectionSearch
    default_filters = dict(is_active=True, version=HEAD)

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

        return CollectionListSerializer

    @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, updated_since_param, include_facets_header, compress_header
        ]
    )
    def get(self, request, *args, **kwargs):
        return self.list(request, *args, **kwargs)

    def get_csv_rows(self, queryset=None):  # pragma: no cover
        if not queryset:
            queryset = self.get_queryset()

        values = queryset.values('mnemonic', 'name', 'full_name', 'collection_type', 'description', 'default_locale',
                                 'supported_locales', 'website', 'external_id', 'updated_at', 'updated_by', 'uri')

        for value in values:
            value['Owner'] = Collection.objects.get(uri=value['uri']).parent.mnemonic
            value['Collection ID'] = value.pop('mnemonic')
            value['Collection Name'] = value.pop('name')
            value['Collection Full Name'] = value.pop('full_name')
            value['Collection Type'] = value.pop('collection_type')
            value['Description'] = value.pop('description')
            value['Default Locale'] = value.pop('default_locale')
            value['Supported Locales'] = ",".join(value.pop('supported_locales'))
            value['Website'] = value.pop('website')
            value['External ID'] = value.pop('external_id')
            value['Last Updated'] = value.pop('updated_at')
            value['Updated By'] = value.pop('updated_by')
            value['URI'] = value.pop('uri')

        values.field_names.extend([
            'Owner', 'Collection ID', 'Collection Name', 'Collection Full Name', 'Collection Type', 'Description',
            'Default Locale', 'Supported Locales', 'Website', 'External ID', 'Last Updated', 'Updated By', 'URI'
        ])
        del values.field_names[0:12]
        return values


class CollectionLogoView(CollectionBaseView, BaseLogoView):
    serializer_class = CollectionDetailSerializer

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

        return [IsAuthenticated(), CanEditConceptDictionary()]


class CollectionRetrieveUpdateDestroyView(CollectionBaseView, ConceptDictionaryUpdateMixin):
    serializer_class = CollectionDetailSerializer

    def get_object(self, queryset=None):
        return self.get_queryset().filter(is_active=True).order_by('-created_at').first()

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

        return [IsAuthenticated(), CanEditConceptDictionary()]

    def delete(self, request, *args, **kwargs):  # pylint: disable=unused-argument
        collection = self.get_object()
        try:
            collection.delete()
        except Exception as ex:
            return Response({'detail': get(ex, 'messages', [DELETE_FAILURE])}, status=status.HTTP_400_BAD_REQUEST)

        return Response({'detail': DELETE_SUCCESS}, status=status.HTTP_204_NO_CONTENT)

    def get(self, request, *args, **kwargs):  # pylint: disable=unused-argument
        instance = self.get_object()

        if not instance:
            return Response(status=status.HTTP_404_NOT_FOUND)

        serializer = self.get_serializer(instance)
        return Response(serializer.data)


class CollectionReferencesView(
        CollectionBaseView, ConceptDictionaryUpdateMixin, RetrieveAPIView, DestroyAPIView, ListWithHeadersMixin
):
    serializer_class = CollectionDetailSerializer

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

        return [CanEditConceptDictionary()]

    def get_object(self, queryset=None):
        instance = super().get_queryset().filter(is_active=True).order_by('-created_at').first()

        if not instance:
            raise Http404(NO_MATCH)

        return instance

    def get_queryset(self):
        search_query = self.request.query_params.get('q', '')
        sort = self.request.query_params.get('search_sort', 'ASC')
        if sort == 'ASC':
            sort = ''
        else:
            sort = '-'

        instance = self.get_object()
        queryset = instance.references

        if search_query:
            queryset = queryset.filter(expression__icontains=search_query).order_by(sort + 'expression')

        return queryset.all()

    def retrieve(self, request, *args, **kwargs):
        self.serializer_class = CollectionReferenceSerializer
        return self.list(request, *args, **kwargs)

    def destroy(self, request, *args, **kwargs):
        instance = self.get_object()
        expressions = request.data.get("references") or request.data.get("expressions")
        if not expressions:
            return Response(status=status.HTTP_400_BAD_REQUEST)

        if expressions == '*':
            expressions = list(instance.references.values_list('expression', flat=True))
        if self.should_cascade_mappings():
            expressions += self.get_related_mappings_with_version_information(instance, expressions)

        instance.delete_references(expressions)
        return Response({'message': OK_MESSAGE}, status=status.HTTP_204_NO_CONTENT)

    def update(self, request, *args, **kwargs):  # pylint: disable=too-many-locals,unused-argument # Fixme: Sny
        collection = self.get_object()

        cascade_mappings = self.should_cascade_mappings()
        data = request.data.get('data')
        concept_expressions = data.get('concepts', [])
        mapping_expressions = data.get('mappings', [])
        expressions = data.get('expressions', [])

        adding_all = mapping_expressions == '*' or concept_expressions == '*'

        if adding_all:
            add_references.delay(self.request.user, data, collection, self.get_host_url(), cascade_mappings)
            return Response([], status=status.HTTP_202_ACCEPTED)

        (added_references, errors) = collection.add_expressions(
            data, self.get_host_url(), request.user, cascade_mappings
        )

        all_expressions = expressions + concept_expressions + mapping_expressions

        added_expressions = [reference.expression for reference in added_references]
        added_original_expressions = set(
            [reference.original_expression for reference in added_references] + all_expressions
        )

        response = []

        for expression in added_original_expressions:
            response_item = self.create_response_item(added_expressions, errors, expression)
            if response_item:
                response.append(response_item)

        return Response(response, status=status.HTTP_200_OK)

    def should_cascade_mappings(self):
        return self.request.query_params.get('cascade', '').lower() == SOURCE_MAPPINGS

    def create_response_item(self, added_expressions, errors, expression):
        adding_expression_failed = len(errors) > 0 and expression in errors
        if adding_expression_failed:
            return self.create_error_message(errors, expression)
        return self.create_success_message(added_expressions, expression)

    def create_success_message(self, added_expressions, expression):
        message = self.select_update_message(expression)

        references = list(filter(lambda expr: expr.startswith(expression), added_expressions))
        if len(references) < 1:
            return None

        return {
            'added': True,
            'expression': references[0],
            'message': message
        }

    @staticmethod
    def create_error_message(errors, expression):
        error_message = errors.get(expression, {})
        return {
            'added': False,
            'expression': expression,
            'message': error_message
        }

    def select_update_message(self, expression):
        adding_head_version = not is_version_specified(expression)

        expression_parts = expression.split('/')
        resource_type = expression_parts[5]

        if adding_head_version:
            return self.adding_to_head_message_by_type(resource_type)

        resource_name = expression_parts[6]
        return self.version_added_message_by_type(resource_name, self.parent_resource.name, resource_type)

    @staticmethod
    def adding_to_head_message_by_type(resource_type):
        if resource_type == 'concepts':
            return HEAD_OF_CONCEPT_ADDED_TO_COLLECTION
        return HEAD_OF_MAPPING_ADDED_TO_COLLECTION

    @staticmethod
    def version_added_message_by_type(resource_name, collection_name, resource_type):
        if resource_type == 'concepts':
            return CONCEPT_ADDED_TO_COLLECTION_FMT.format(resource_name, collection_name)
        return MAPPING_ADDED_TO_COLLECTION_FMT.format(resource_name, collection_name)

    def get_related_mappings_with_version_information(self, instance, expressions):
        related_mappings = []

        for expression in expressions:
            if is_concept(expression):
                concepts = CollectionReference.get_concept_heads_from_expression(expression)
                for concept in concepts:
                    related_mappings += concept.get_unidirectional_mappings()

        return self.get_version_information_of_related_mappings(instance, related_mappings)

    @staticmethod
    def get_version_information_of_related_mappings(instance, related_mappings):
        return list(
            instance.references.filter(
                expression__in=[mapping.url for mapping in related_mappings]
            ).values_list('expression', flat=True)
        )


class CollectionVersionReferencesView(CollectionVersionBaseView, ListWithHeadersMixin):
    serializer_class = CollectionReferenceSerializer

    def get(self, request, *args, **kwargs):
        query_params = self.request.query_params
        search_query = query_params.get('q', '')
        sort = query_params.get('search_sort', 'ASC')
        object_version = self.get_queryset().first().head
        references = object_version.references.filter(expression__icontains=search_query)
        self.object_list = references if sort == 'ASC' else list(reversed(references))
        return self.list(request, *args, **kwargs)


class CollectionVersionListView(CollectionVersionBaseView, mixins.CreateModelMixin, ListWithHeadersMixin):
    released_filter = None
    processing_filter = None
    default_qs_sort_attr = 'created_at'

    def get_serializer_class(self):
        if self.request.method in ['GET', 'HEAD']:
            return CollectionVersionDetailSerializer if self.is_verbose() else CollectionListSerializer
        if self.request.method == 'POST':
            return CollectionCreateSerializer

        return CollectionVersionListSerializer

    def get(self, request, *args, **kwargs):
        self.released_filter = parse_boolean_query_param(request, RELEASED_PARAM, self.released_filter)
        self.processing_filter = parse_boolean_query_param(request, PROCESSING_PARAM, self.processing_filter)
        return self.list(request, *args, **kwargs)

    def post(self, request, *args, **kwargs):
        return self.create(request, *args, **kwargs)

    def create(self, request, *args, **kwargs):
        head_object = self.get_queryset().first()
        version = request.data.pop('id', None)
        payload = {
            "mnemonic": head_object.mnemonic, "id": head_object.mnemonic, "name": head_object.name, **request.data,
            "organization_id": head_object.organization_id, "user_id": head_object.user_id,
            'version': version
        }
        serializer = self.get_serializer(data=payload)
        if serializer.is_valid():
            try:
                instance = serializer.create_version(payload)
                if serializer.is_valid():
                    serializer = CollectionDetailSerializer(instance, context={'request': request})
                    data = serializer.data
                    version_id = data.get('uuid')
                    export_collection.delay(version_id)
                    return Response(data, status=status.HTTP_201_CREATED)
            except IntegrityError as ex:
                return Response(
                    dict(
                        error=str(ex), detail=VERSION_ALREADY_EXISTS.format(version)
                    ),
                    status=status.HTTP_409_CONFLICT
                )

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

    def get_queryset(self):
        queryset = super().get_queryset()
        if self.released_filter is not None:
            queryset = queryset.filter(released=self.released_filter)
        return queryset.order_by('-created_at')


class CollectionLatestVersionRetrieveUpdateView(CollectionVersionBaseView, RetrieveAPIView, UpdateAPIView):
    serializer_class = CollectionVersionDetailSerializer
    permission_classes = (CanViewConceptDictionaryVersion,)

    def get_filter_params(self, default_version_to_head=False):
        params = super().get_filter_params(default_version_to_head)
        params['is_latest'] = True
        return params

    def get_object(self, queryset=None):
        obj = get_object_or_404(self.get_queryset(), released=True)
        self.check_object_permissions(self.request, obj)
        return obj

    def update(self, request, *args, **kwargs):
        self.object = self.get_object()
        head = self.object.head
        if not head:
            return Response(status=status.HTTP_405_METHOD_NOT_ALLOWED)

        serializer = self.get_serializer(self.object, data=request.data, partial=True)

        if serializer.is_valid():
            self.object = serializer.save(force_update=True)
            if serializer.is_valid():
                serializer = CollectionVersionDetailSerializer(self.object, context={'request': request})
                return Response(serializer.data, status=status.HTTP_200_OK)

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


class CollectionVersionRetrieveUpdateDestroyView(CollectionBaseView, RetrieveAPIView, UpdateAPIView):
    permission_classes = (HasAccessToVersionedObject,)
    serializer_class = CollectionVersionDetailSerializer

    def get_object(self, queryset=None):
        return get_object_or_404(self.get_queryset())

    def update(self, request, *args, **kwargs):
        self.object = self.get_object()
        head = self.object.head
        if not head:
            return Response(status=status.HTTP_405_METHOD_NOT_ALLOWED)

        serializer = self.get_serializer(self.object, data=request.data, partial=True)

        if serializer.is_valid():
            self.object = serializer.save(force_update=True)
            if serializer.is_valid():
                return Response(serializer.data, status=status.HTTP_200_OK)

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

    def delete(self, _, **kwargs):  # pylint: disable=unused-argument
        instance = self.get_object()

        try:
            instance.delete()
        except ValidationError as ex:
            return Response(ex.message_dict, status=status.HTTP_400_BAD_REQUEST)

        return Response(status=status.HTTP_204_NO_CONTENT)


class CollectionExtrasBaseView(CollectionBaseView):
    def get_object(self, queryset=None):
        return get_object_or_404(self.get_queryset(), version=HEAD)


class CollectionExtrasView(CollectionExtrasBaseView, ListAPIView):
    serializer_class = CollectionDetailSerializer

    def list(self, request, *args, **kwargs):
        return Response(get(self.get_object(), 'extras', {}))


class CollectionExtraRetrieveUpdateDestroyView(CollectionExtrasBaseView, RetrieveUpdateDestroyAPIView):
    serializer_class = CollectionDetailSerializer

    def retrieve(self, request, *args, **kwargs):
        key = kwargs.get('extra')
        instance = self.get_object()
        extras = get(instance, 'extras', {})
        if key in extras:
            return Response({key: extras[key]})

        return Response(dict(detail=NOT_FOUND), status=status.HTTP_404_NOT_FOUND)

    def update(self, request, **kwargs):
        key = kwargs.get('extra')
        value = request.data.get(key)
        if not value:
            return Response([MUST_SPECIFY_EXTRA_PARAM_IN_BODY.format(key)], status=status.HTTP_400_BAD_REQUEST)

        instance = self.get_object()
        instance.extras = get(instance, 'extras', {})
        instance.extras[key] = value
        instance.comment = 'Updated extras: %s=%s.' % (key, value)
        head = instance.get_head()
        head.extras = get(head, 'extras', {})
        head.extras.update(instance.extras)
        instance.save()
        head.save()
        return Response({key: value})

    def delete(self, request, *args, **kwargs):
        key = kwargs.get('extra')
        instance = self.get_object()
        instance.extras = get(instance, 'extras', {})
        if key in instance.extras:
            del instance.extras[key]
            instance.comment = 'Deleted extra %s.' % key
            head = instance.get_head()
            head.extras = get(head, 'extras', {})
            del head.extras[key]
            instance.save()
            head.save()
            return Response(status=status.HTTP_204_NO_CONTENT)

        return Response(dict(detail=NOT_FOUND), status=status.HTTP_404_NOT_FOUND)


class CollectionVersionProcessingView(CollectionBaseView, ConceptContainerProcessingMixin):
    serializer_class = CollectionVersionDetailSerializer
    resource = 'collection'


class CollectionVersionExportView(ConceptContainerExportMixin, CollectionVersionBaseView):
    entity = 'Collection'
    permission_classes = (CanViewConceptDictionary,)
    serializer_class = CollectionVersionDetailSerializer

    def handle_export_version(self):
        version = self.get_object()
        try:
            export_collection.delay(version.id)
            return status.HTTP_202_ACCEPTED
        except AlreadyQueued:
            return status.HTTP_409_CONFLICT