# Copyright 2017-present Open Networking Foundation
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

""" fake_stub.py

    Implements a simple fake grpc stub to use for unit testing.
"""

import functools

ContentTypeMap = {}


class FakeObj(object):
    BASES = []

    def __init__(self, fields=[], **kwargs):
        super(FakeObj, self).__setattr__("is_set", {})
        super(FakeObj, self).__setattr__("fields", [])

        for f in fields:
            name = f["name"]
            self.fields.append(name)
            setattr(self, name, f["default"])

        super(FakeObj, self).__setattr__("is_set", {})
        for (k, v) in kwargs.items():
            setattr(self, k, v)

    def __repr__(self):
        lines = []
        for k in self.fields:
            if self.is_set.get(k, False):
                lines.append('%s: "%s"' % (k, getattr(self, k)))
        if lines:
            return "\n".join(lines) + "\n"
        else:
            return ""

    def __setattr__(self, name, value):
        self.is_set[name] = True
        super(FakeObj, self).__setattr__(name, value)

    def HasField(self, name):
        """ Return True if the field is set in the protobuf. """

        # gRPC throws a valueerror if the field doesn't exist in the schema
        if name not in self.fields:
            raise ValueError("Field %s does not exist in schema" % name)

        # Fields that are always set
        if name in ["leaf_model_name"]:
            return True

        field = self.DESCRIPTOR.fields_by_name[name].field_decl

        # Reverse foreign keys lists are never None, they are an empty list
        if field.get("fk_reverse", None):
            return True

        return self.is_set.get(name, False)

    def ListFields(self):
        fbn = self.DESCRIPTOR.fields_by_name
        fieldlist = []
        for (k, v) in fbn.items():
            if self.is_set.get(k, False):
                fieldlist.append((v, getattr(self, k)))
        return fieldlist

    @property
    def self_content_type_id(self):
        return "xos.%s" % self.__class__.__name__.lower()


class FakeExtensionManager(object):
    def __init__(self, obj, extensions):
        self.obj = obj
        self.extensions = extensions

    def _FindExtensionByName(self, name):
        return name

    def __getitem__(self, name, default=None):
        if name in self.extensions:
            return self.extensions[name]
        return default


class FakeFieldOption(object):
    def __init__(self, modelName=None, reverseFieldName=None):
        self.modelName = modelName
        self.reverseFieldName = reverseFieldName


class FakeField(object):
    def __init__(self, field):
        extensions = {}

        self.field_decl = field
        self.name = field["name"]

        fk_model = field.get("fk_model", None)
        if fk_model:
            reverseFieldName = field.get("fk_reverseFieldName", None)
            extensions["xos.foreignKey"] = FakeFieldOption(
                modelName=fk_model, reverseFieldName=reverseFieldName
            )

        fk_reverse = field.get("fk_reverse", None)
        if fk_reverse:
            extensions["xos.reverseForeignKey"] = FakeFieldOption(modelName=fk_reverse)

        self.Extensions = FakeExtensionManager(self, extensions)

    def GetOptions(self):
        return self


class FakeDescriptor(object):
    def __init__(self, objName):
        global ContentTypeIdCounter
        global ContentTypeMap
        self.objName = objName
        if objName in ContentTypeMap:
            ct = ContentTypeMap[objName]
        else:
            ct = "xos.%s" % objName.lower()
            ContentTypeMap[objName] = ct
        self.Extensions = FakeExtensionManager(self, {"xos.contentTypeId": ct})

    def GetOptions(self):
        return self

    @property
    def fields_by_name(self):
        cls = globals()[self.objName]
        fbn = {}
        for field in cls.FIELDS:
            fake_field = FakeField(field)
            fbn[field["name"]] = fake_field

        return fbn


class Controller(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "name", "default": ""},
        {"name": "deployment_id", "default": 0, "fk_model": "Deployment"},
        {"name": "class_names", "default": "Controller"},
    )

    def __init__(self, **kwargs):
        return super(Controller, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("Controller")


class Deployment(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "name", "default": ""},
        {"name": "class_names", "default": "Deployment"},
    )

    def __init__(self, **kwargs):
        return super(Deployment, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("Controller")


class User(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "email", "default": ""},
        {"name": "site_id", "default": 0, "fk_model": "Site"},
        {"name": "class_names", "default": "User"},
    )

    def __init__(self, **kwargs):
        return super(User, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("User")


class Slice(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "name", "default": ""},
        {
            "name": "site_id",
            "default": 0,
            "fk_model": "Site",
            "fk_reverseFieldName": "slices",
        },
        {"name": "service_id", "default": 0, "fk_model": "Service"},
        {"name": "creator_id", "default": 0, "fk_model": "User"},
        {"name": "networks_ids", "default": [], "fk_reverse": "Network"},
        {"name": "network", "default": ""},
        {"name": "leaf_model_name", "default": "Slice"},
        {"name": "class_names", "default": "Slice"},
    )

    def __init__(self, **kwargs):
        return super(Slice, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("Slice")


class Site(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "name", "default": ""},
        {"name": "login_base", "default": ""},
        {"name": "slices_ids", "default": [], "fk_reverse": "Slice"},
        {"name": "leaf_model_name", "default": "Site"},
        {"name": "class_names", "default": "Site"},
    )

    def __init__(self, **kwargs):
        return super(Site, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("Site")


class Service(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "name", "default": ""},
        {"name": "slices_ids", "default": [], "fk_reverse": "Slice"},
        {"name": "leaf_model_name", "default": "Service"},
        {"name": "class_names", "default": "Service"},
    )

    def __init__(self, **kwargs):
        return super(Service, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("Service")


class ServiceInstance(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "owher", "default": 0, "fk_model": "Service"},
        {"name": "leaf_model_name", "default": "ServiceInstance"},
        {"name": "class_names", "default": "ServiceInstance"},
    )

    def __init__(self, **kwargs):
        return super(ServiceInstance, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("ServiceInstance")


class ONOSService(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "name", "default": ""},
        {"name": "leaf_model_name", "default": "ONOSService"},
        {"name": "class_names", "default": "ONOSService,Service"},
    )

    BASES = ["Service"]

    def __init__(self, **kwargs):
        return super(ONOSService, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("ONOSService")


class Network(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "name", "default": ""},
        {"name": "owner_id", "default": 0, "fk_model": "Slice"},
        {"name": "template_id", "default": 0, "fk_model": "NetworkTemplate"},
        {
            "name": "controllernetworks_ids",
            "default": [],
            "fk_reverse": "ControllerNetwork",
        },
        {"name": "leaf_model_name", "default": "Network"},
        {"name": "class_names", "default": "Network"},
    )

    def __init__(self, **kwargs):
        return super(Network, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("Network")


class NetworkTemplate(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "name", "default": ""},
        {"name": "vtn_kind", "default": ""},
        {"name": "leaf_model_name", "default": "NetworkTemplate"},
        {"name": "class_names", "default": "NetworkTemplate"},
    )

    def __init__(self, **kwargs):
        return super(NetworkTemplate, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("NetworkTemplate")


class ControllerNetwork(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "network_id", "default": 0, "fk_model": "Network"},
        {"name": "controller_id", "default": 0, "fk_model": "Controller"},
        {"name": "leaf_model_name", "default": "ControllerNetwork"},
        {"name": "class_names", "default": "ControllerNetwork"},
    )

    def __init__(self, **kwargs):
        return super(ControllerNetwork, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("ControllerNetwork")


class NetworkSlice(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "network_id", "default": 0, "fk_model": "Network"},
        {"name": "slice_id", "default": 0, "fk_model": "Slice"},
        {"name": "leaf_model_name", "default": "NetworkSlice"},
        {"name": "class_names", "default": "NetworkSlice"},
    )

    def __init__(self, **kwargs):
        return super(NetworkSlice, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("NetworkSlice")


class Tag(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "service_id", "default": None},
        {"name": "name", "default": ""},
        {"name": "value", "default": ""},
        {"name": "content_type", "default": None},
        {"name": "object_id", "default": None},
        {"name": "leaf_model_name", "default": "Tag"},
        {"name": "class_names", "default": "Tag"},
    )

    def __init__(self, **kwargs):
        return super(Tag, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("Tag")


class TestModel(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "intfield", "default": 0},
        {"name": "stringfield", "default": "somestring"},
        {"name": "testmodeltwos_ids", "default": [], "fk_reverse": "TestModelTwo"},
        {"name": "class_names", "default": "TestModel"},
    )

    def __init__(self, **kwargs):
        return super(TestModel, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("TestModel")


class TestModelTwo(FakeObj):
    FIELDS = (
        {"name": "id", "default": 0},
        {"name": "intfieldtwo", "default": 0},
        {"name": "stringfieldtwo", "default": "somestringtwo"},
        {
            "name": "testmodel_id",
            "default": 0,
            "fk_model": "TestModel",
            "fk_reverseFieldName": "testmodeltwos",
        },
        {"name": "class_names", "default": "TestModel"},
    )

    def __init__(self, **kwargs):
        return super(TestModelTwo, self).__init__(self.FIELDS, **kwargs)

    DESCRIPTOR = FakeDescriptor("TestModelTwo")


class ID(FakeObj):
    pass


class FakeItemList(object):
    def __init__(self, items):
        self.items = items


class FakeElement(object):
    EQUAL = "equal"
    IEXACT = "iexact"

    def __init__(self):
        pass


class FakeElements(object):
    def __init__(self):
        self.items = []

    def add(self):
        el = FakeElement()
        self.items.append(el)
        return el

    def __getitem__(self, index):
        return self.items[index]

    def __len__(self):
        return len(self.items)


class FakeQuery(object):
    DEFAULT = 0
    ALL = 1
    SYNCHRONIZER_DIRTY_OBJECTS = 2
    SYNCHRONIZER_DELETED_OBJECTS = 3
    SYNCHRONIZER_DIRTY_POLICIES = 4
    SYNCHRONIZER_DELETED_POLICIES = 5

    def __init__(self):
        self.elements = FakeElements()


class FakeStub(object):
    def __init__(self):
        self.id_counter = 1
        self.objs = {}
        self.deleted_objs = {}
        for name in [
            "Controller",
            "Deployment",
            "Slice",
            "Site",
            "Tag",
            "Service",
            "ServiceInstance",
            "ONOSService",
            "User",
            "Network",
            "NetworkTemplate",
            "ControllerNetwork",
            "NetworkSlice",
            "TestModel",
            "TestModelTwo",
        ]:
            setattr(self, "Get%s" % name, functools.partial(self.get, name))
            setattr(self, "List%s" % name, functools.partial(self.list, name))
            setattr(self, "Create%s" % name, functools.partial(self.create, name))
            setattr(self, "Delete%s" % name, functools.partial(self.delete, name))
            setattr(self, "Update%s" % name, functools.partial(self.update, name))
            setattr(self, "Filter%s" % name, functools.partial(self.filter, name))

    def make_key(self, name, id):
        return "%s:%d" % (name, id.id)

    def get(self, classname, id, metadata=None):
        obj = self.objs.get(self.make_key(classname, id), None)
        return obj

    def list(self, classname, empty, metadata=None):
        items = []
        for (k, v) in self.objs.items():
            (this_classname, id) = k.split(":")
            if this_classname == classname:
                items.append(v)
        return FakeItemList(items)

    def filter(self, classname, query, metadata=None):
        items = []

        if query.kind == FakeQuery.SYNCHRONIZER_DELETED_OBJECTS:
            objs = self.deleted_objs.items()
        else:
            objs = self.objs.items()

        for (k, v) in objs:
            (this_classname, id) = k.split(":")
            if this_classname != classname:
                continue
            match = True
            for q in query.elements.items:
                iValue = getattr(q, "iValue", None)
                if (iValue is not None) and getattr(v, q.name) != iValue:
                    match = False
                sValue = getattr(q, "sValue", None)
                if (sValue is not None) and getattr(v, q.name) != sValue:
                    match = False
            if match:
                items.append(v)
        return FakeItemList(items)

    def create(self, classname, obj, metadata=None):
        obj.id = self.id_counter
        self.id_counter = self.id_counter + 1
        k = self.make_key(classname, FakeObj(id=obj.id))
        self.objs[k] = obj

        for base_classname in obj.BASES:
            base_class = globals()[base_classname]
            base_obj = base_class(id=obj.id, leaf_model_name=classname)
            k = self.make_key(base_classname, base_obj)
            self.objs[k] = base_obj

        return obj

    def update(self, classname, obj, metadata=None):
        # TODO: partial update support?
        k = self.make_key(classname, FakeObj(id=obj.id))
        self.objs[k] = obj
        return obj

    def delete(self, classname, id, metadata=None):
        k = self.make_key(classname, id)
        obj = self.objs[k]
        del self.objs[k]
        self.deleted_objs[k] = obj


class FakeCommonProtos(object):
    def __init__(self):
        self.ID = ID
        self.Query = FakeQuery


class FakeProtos(object):
    def __init__(self):
        for name in [
            "Controller",
            "Deployment",
            "Slice",
            "Site",
            "ID",
            "Tag",
            "Service",
            "ServiceInstance",
            "ONOSService",
            "User",
            "Network",
            "NetworkTemplate",
            "ControllerNetwork",
            "NetworkSlice",
            "TestModel",
            "TestModelTwo",
        ]:
            setattr(self, name, globals()[name])
            self.common__pb2 = FakeCommonProtos()


class FakeSymDb(object):
    def __init__(self):
        self._classes = {}
        for name in [
            "Controller",
            "Deployment",
            "Slice",
            "Site",
            "ID",
            "Tag",
            "Service",
            "ServiceInstance",
            "ONOSService",
            "User",
            "Network",
            "NetworkTemplate",
            "ControllerNetwork",
            "NetworkSlice",
            "TestModel",
            "TestModelTwo",
        ]:
            self._classes["xos.%s" % name] = globals()[name]