/*
Copyright 2020 The Knative Authors.

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.
*/

package v1

import (
	"context"
	"encoding/json"
	"testing"

	fakecachingclient "knative.dev/caching/pkg/client/injection/client/fake"
	fakekubeclient "knative.dev/pkg/client/injection/kube/client/fake"
	fakedynamicclient "knative.dev/pkg/injection/clients/dynamicclient/fake"
	v1 "knative.dev/serving/pkg/apis/serving/v1"
	fakeservingclient "knative.dev/serving/pkg/client/injection/client/fake"
	fakeistioclient "knative.dev/serving/pkg/client/istio/injection/client/fake"

	"knative.dev/pkg/configmap"
	"knative.dev/pkg/controller"
	"knative.dev/pkg/logging"
	logtesting "knative.dev/pkg/logging/testing"

	"k8s.io/apimachinery/pkg/api/meta"
	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/runtime/schema"
	ktesting "k8s.io/client-go/testing"
	"k8s.io/client-go/tools/record"

	rtesting "knative.dev/pkg/reconciler/testing"
)

const (
	// maxEventBufferSize is the estimated max number of event notifications that
	// can be buffered during reconciliation.
	maxEventBufferSize = 10
)

// Ctor functions create a k8s controller with given params.
type Ctor func(context.Context, *Listers, configmap.Watcher) controller.Reconciler

// MakeFactory creates a reconciler factory with fake clients and controller created by `ctor`.
func MakeFactory(ctor Ctor) rtesting.Factory {
	return func(t *testing.T, r *rtesting.TableRow) (
		controller.Reconciler, rtesting.ActionRecorderList, rtesting.EventList) {
		ls := NewListers(r.Objects)

		ctx := r.Ctx
		if ctx == nil {
			ctx = context.Background()
		}
		logger := logtesting.TestLogger(t)
		ctx = logging.WithLogger(ctx, logger)

		ctx, kubeClient := fakekubeclient.With(ctx, ls.GetKubeObjects()...)
		ctx, istioClient := fakeistioclient.With(ctx, ls.GetIstioObjects()...)
		ctx, client := fakeservingclient.With(ctx, ls.GetServingObjects()...)
		ctx, dynamicClient := fakedynamicclient.With(ctx,
			ls.NewScheme(), ToUnstructured(t, ls.NewScheme(), r.Objects)...)
		ctx, cachingClient := fakecachingclient.With(ctx, ls.GetCachingObjects()...)
		ctx = context.WithValue(ctx, TrackerKey, &rtesting.FakeTracker{})

		// The dynamic client's support for patching is BS.  Implement it
		// here via PrependReactor (this can be overridden below by the
		// provided reactors).
		dynamicClient.PrependReactor("patch", "*",
			func(action ktesting.Action) (bool, runtime.Object, error) {
				return true, nil, nil
			})

		eventRecorder := record.NewFakeRecorder(maxEventBufferSize)
		ctx = controller.WithEventRecorder(ctx, eventRecorder)

		// This is needed for the tests that use generated names and
		// the object cannot be created beforehand.
		kubeClient.PrependReactor("create", "*",
			func(action ktesting.Action) (bool, runtime.Object, error) {
				ca := action.(ktesting.CreateAction)
				ls.IndexerFor(ca.GetObject()).Add(ca.GetObject())
				return false, nil, nil
			},
		)
		// This is needed by the Configuration controller tests, which
		// use GenerateName to produce Revisions.
		rtesting.PrependGenerateNameReactor(&client.Fake)

		// Set up our Controller from the fakes.
		c := ctor(ctx, &ls, configmap.NewStaticWatcher())
		// Update the context with the stuff we decorated it with.
		r.Ctx = ctx

		for _, reactor := range r.WithReactors {
			kubeClient.PrependReactor("*", "*", reactor)
			istioClient.PrependReactor("*", "*", reactor)
			client.PrependReactor("*", "*", reactor)
			dynamicClient.PrependReactor("*", "*", reactor)
			cachingClient.PrependReactor("*", "*", reactor)
		}

		// Validate all Create operations through the serving client.
		client.PrependReactor("create", "*", func(action ktesting.Action) (handled bool, ret runtime.Object, err error) {
			// TODO(n3wscott): context.Background is the best we can do at the moment, but it should be set-able.
			return rtesting.ValidateCreates(context.Background(), action)
		})
		client.PrependReactor("update", "*", func(action ktesting.Action) (handled bool, ret runtime.Object, err error) {
			// TODO(n3wscott): context.Background is the best we can do at the moment, but it should be set-able.
			return rtesting.ValidateUpdates(context.Background(), action)
		})

		actionRecorderList := rtesting.ActionRecorderList{istioClient, dynamicClient, client, kubeClient, cachingClient}
		eventList := rtesting.EventList{Recorder: eventRecorder}

		return c, actionRecorderList, eventList
	}
}

// ToUnstructured takes a list of k8s resources and converts them to
// Unstructured objects.
// We must pass objects as Unstructured to the dynamic client fake, or it
// won't handle them properly.
func ToUnstructured(t *testing.T, sch *runtime.Scheme, objs []runtime.Object) (us []runtime.Object) {
	for _, obj := range objs {
		obj = obj.DeepCopyObject() // Don't mess with the primary copy
		// Determine and set the TypeMeta for this object based on our test scheme.
		gvks, _, err := sch.ObjectKinds(obj)
		if err != nil {
			t.Fatal("Unable to determine kind for type:", err)
		}
		apiv, k := gvks[0].ToAPIVersionAndKind()
		ta, err := meta.TypeAccessor(obj)
		if err != nil {
			t.Fatal("Unable to create type accessor:", err)
		}
		ta.SetAPIVersion(apiv)
		ta.SetKind(k)

		b, err := json.Marshal(obj)
		if err != nil {
			t.Fatal("Unable to marshal:", err)
		}
		u := &unstructured.Unstructured{}
		if err := json.Unmarshal(b, u); err != nil {
			t.Fatal("Unable to unmarshal:", err)
		}
		us = append(us, u)
	}
	return
}

type key struct{}

// TrackerKey is used to looking a FakeTracker in a context.Context
var TrackerKey key = struct{}{}

// AssertTrackingConfig will ensure the provided Configuration is being tracked
func AssertTrackingConfig(namespace, name string) func(*testing.T, *rtesting.TableRow) {
	gvk := v1.SchemeGroupVersion.WithKind("Configuration")
	return AssertTrackingObject(gvk, namespace, name)
}

// AssertTrackingRevision will ensure the provided Revision is being tracked
func AssertTrackingRevision(namespace, name string) func(*testing.T, *rtesting.TableRow) {
	gvk := v1.SchemeGroupVersion.WithKind("Revision")
	return AssertTrackingObject(gvk, namespace, name)
}

// AssertTrackingObject will ensure the following objects are being tracked
func AssertTrackingObject(gvk schema.GroupVersionKind, namespace, name string) func(*testing.T, *rtesting.TableRow) {
	apiVersion, kind := gvk.ToAPIVersionAndKind()

	return func(t *testing.T, r *rtesting.TableRow) {
		tracker := r.Ctx.Value(TrackerKey).(*rtesting.FakeTracker)
		refs := tracker.References()

		for _, ref := range refs {
			if ref.APIVersion == apiVersion &&
				ref.Name == name &&
				ref.Namespace == namespace &&
				ref.Kind == kind {
				return
			}
		}

		t.Errorf("Object was not tracked - %s, Name=%s, Namespace=%s", gvk.String(), name, namespace)
	}

}
