// Copyright © 2017 The virtual-kubelet 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 node

import (
	"context"
	"testing"
	"time"

	testutil "github.com/virtual-kubelet/virtual-kubelet/internal/test/util"
	"gotest.tools/assert"
	is "gotest.tools/assert/cmp"
	corev1 "k8s.io/api/core/v1"
	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	kubeinformers "k8s.io/client-go/informers"
	"k8s.io/client-go/kubernetes/fake"
	"k8s.io/client-go/util/workqueue"
)

type TestController struct {
	*PodController
	mock   *mockProviderAsync
	client *fake.Clientset
}

func newTestController() *TestController {
	fk8s := fake.NewSimpleClientset()

	rm := testutil.FakeResourceManager()
	p := newMockProvider()
	iFactory := kubeinformers.NewSharedInformerFactoryWithOptions(fk8s, 10*time.Minute)
	return &TestController{
		PodController: &PodController{
			client:          fk8s.CoreV1(),
			provider:        p,
			resourceManager: rm,
			recorder:        testutil.FakeEventRecorder(5),
			k8sQ:            workqueue.NewRateLimitingQueue(workqueue.DefaultControllerRateLimiter()),
			deletionQ:       workqueue.NewRateLimitingQueue(workqueue.DefaultControllerRateLimiter()),
			done:            make(chan struct{}),
			ready:           make(chan struct{}),
			podsInformer:    iFactory.Core().V1().Pods(),
		},
		mock:   p,
		client: fk8s,
	}
}

// Run starts the informer and runs the pod controller
func (tc *TestController) Run(ctx context.Context, n int) error {
	go tc.podsInformer.Informer().Run(ctx.Done())
	return tc.PodController.Run(ctx, n)
}

func TestPodsEqual(t *testing.T) {
	p1 := &corev1.Pod{
		Spec: corev1.PodSpec{
			Containers: []corev1.Container{
				{
					Name:  "nginx",
					Image: "nginx:1.15.12-perl",
					Ports: []corev1.ContainerPort{
						{
							ContainerPort: 443,
							Protocol:      "tcp",
						},
					},
				},
			},
		},
	}

	p2 := p1.DeepCopy()

	assert.Assert(t, podsEqual(p1, p2))
}

func TestPodsDifferent(t *testing.T) {
	p1 := &corev1.Pod{
		Spec: newPodSpec(),
	}

	p2 := p1.DeepCopy()
	p2.Spec.Containers[0].Image = "nginx:1.15.12-perl"

	assert.Assert(t, !podsEqual(p1, p2))
}

func TestPodsDifferentIgnoreValue(t *testing.T) {
	p1 := &corev1.Pod{
		Spec: newPodSpec(),
	}

	p2 := p1.DeepCopy()
	p2.Status.Phase = corev1.PodFailed

	assert.Assert(t, podsEqual(p1, p2))
}

func TestPodShouldEnqueueDifferentDeleteTimeStamp(t *testing.T) {
	p1 := &corev1.Pod{
		Spec: newPodSpec(),
	}

	p2 := p1.DeepCopy()
	now := v1.NewTime(time.Now())
	p2.DeletionTimestamp = &now
	assert.Assert(t, podShouldEnqueue(p1, p2))
}

func TestPodShouldEnqueueDifferentLabel(t *testing.T) {
	p1 := &corev1.Pod{
		Spec: newPodSpec(),
	}

	p2 := p1.DeepCopy()
	p2.Labels = map[string]string{"test": "test"}
	assert.Assert(t, podShouldEnqueue(p1, p2))
}

func TestPodShouldEnqueueDifferentAnnotation(t *testing.T) {
	p1 := &corev1.Pod{
		Spec: newPodSpec(),
	}

	p2 := p1.DeepCopy()
	p2.Annotations = map[string]string{"test": "test"}
	assert.Assert(t, podShouldEnqueue(p1, p2))
}

func TestPodShouldNotEnqueueDifferentStatus(t *testing.T) {
	p1 := &corev1.Pod{
		Spec: newPodSpec(),
	}

	p2 := p1.DeepCopy()
	p2.Status.Phase = corev1.PodSucceeded
	assert.Assert(t, !podShouldEnqueue(p1, p2))
}

func TestPodShouldEnqueueDifferentDeleteGraceTime(t *testing.T) {
	p1 := &corev1.Pod{
		Spec: newPodSpec(),
	}

	p2 := p1.DeepCopy()
	oldTime := v1.NewTime(time.Now().Add(5))
	newTime := v1.NewTime(time.Now().Add(10))
	oldGraceTime := int64(5)
	newGraceTime := int64(10)
	p1.DeletionGracePeriodSeconds = &oldGraceTime
	p2.DeletionTimestamp = &oldTime

	p2.DeletionGracePeriodSeconds = &newGraceTime
	p2.DeletionTimestamp = &newTime
	assert.Assert(t, podShouldEnqueue(p1, p2))
}

func TestPodShouldEnqueueGraceTimeChanged(t *testing.T) {
	p1 := &corev1.Pod{
		Spec: newPodSpec(),
	}

	p2 := p1.DeepCopy()
	graceTime := int64(30)
	p2.DeletionGracePeriodSeconds = &graceTime
	assert.Assert(t, podShouldEnqueue(p1, p2))
}

func TestPodCreateNewPod(t *testing.T) {
	svr := newTestController()

	pod := &corev1.Pod{}
	pod.ObjectMeta.Namespace = "default" //nolint:goconst
	pod.ObjectMeta.Name = "nginx"        //nolint:goconst
	pod.Spec = newPodSpec()

	err := svr.createOrUpdatePod(context.Background(), pod.DeepCopy())

	assert.Check(t, is.Nil(err))
	// createOrUpdate called CreatePod but did not call UpdatePod because the pod did not exist
	assert.Check(t, is.Equal(svr.mock.creates.read(), 1))
	assert.Check(t, is.Equal(svr.mock.updates.read(), 0))
}

func TestPodUpdateExisting(t *testing.T) {
	svr := newTestController()

	pod := &corev1.Pod{}
	pod.ObjectMeta.Namespace = "default"
	pod.ObjectMeta.Name = "nginx"
	pod.Spec = newPodSpec()

	err := svr.createOrUpdatePod(context.Background(), pod.DeepCopy())
	assert.Check(t, is.Nil(err))
	assert.Check(t, is.Equal(svr.mock.creates.read(), 1))
	assert.Check(t, is.Equal(svr.mock.updates.read(), 0))

	pod2 := pod.DeepCopy()
	pod2.Spec.Containers[0].Image = "nginx:1.15.12-perl"

	err = svr.createOrUpdatePod(context.Background(), pod2.DeepCopy())
	assert.Check(t, is.Nil(err))

	// createOrUpdate didn't call CreatePod but did call UpdatePod because the spec changed
	assert.Check(t, is.Equal(svr.mock.creates.read(), 1))
	assert.Check(t, is.Equal(svr.mock.updates.read(), 1))
}

func TestPodNoSpecChange(t *testing.T) {
	svr := newTestController()

	pod := &corev1.Pod{}
	pod.ObjectMeta.Namespace = "default"
	pod.ObjectMeta.Name = "nginx"
	pod.Spec = newPodSpec()

	err := svr.createOrUpdatePod(context.Background(), pod.DeepCopy())
	assert.Check(t, is.Nil(err))
	assert.Check(t, is.Equal(svr.mock.creates.read(), 1))
	assert.Check(t, is.Equal(svr.mock.updates.read(), 0))

	err = svr.createOrUpdatePod(context.Background(), pod.DeepCopy())
	assert.Check(t, is.Nil(err))

	// createOrUpdate didn't call CreatePod or UpdatePod, spec didn't change
	assert.Check(t, is.Equal(svr.mock.creates.read(), 1))
	assert.Check(t, is.Equal(svr.mock.updates.read(), 0))
}

func newPodSpec() corev1.PodSpec {
	return corev1.PodSpec{
		Containers: []corev1.Container{
			{
				Name:  "nginx",
				Image: "nginx:1.15.12",
				Ports: []corev1.ContainerPort{
					{
						ContainerPort: 443,
						Protocol:      "tcp",
					},
				},
			},
		},
	}
}