/*
Copyright 2021 The Kubernetes 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 nodeutilization

import (
	"context"
	"fmt"
	"strings"
	"testing"

	v1 "k8s.io/api/core/v1"
	"k8s.io/api/policy/v1beta1"
	"k8s.io/apimachinery/pkg/api/resource"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/client-go/kubernetes/fake"
	core "k8s.io/client-go/testing"
	"sigs.k8s.io/descheduler/pkg/api"
	"sigs.k8s.io/descheduler/pkg/descheduler/evictions"
	"sigs.k8s.io/descheduler/pkg/utils"
	"sigs.k8s.io/descheduler/test"
)

func TestHighNodeUtilization(t *testing.T) {
	ctx := context.Background()
	n1NodeName := "n1"
	n2NodeName := "n2"
	n3NodeName := "n3"

	nodeSelectorKey := "datacenter"
	nodeSelectorValue := "west"

	testCases := []struct {
		name                  string
		thresholds            api.ResourceThresholds
		nodes                 map[string]*v1.Node
		pods                  map[string]*v1.PodList
		maxPodsToEvictPerNode int
		expectedPodsEvicted   int
		evictedPods           []string
	}{
		{
			name: "no node below threshold usage",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU:  20,
				v1.ResourcePods: 20,
			},
			nodes: map[string]*v1.Node{
				n1NodeName: test.BuildTestNode(n1NodeName, 4000, 3000, 10, nil),
				n2NodeName: test.BuildTestNode(n2NodeName, 4000, 3000, 10, nil),
				n3NodeName: test.BuildTestNode(n3NodeName, 4000, 3000, 10, nil),
			},
			pods: map[string]*v1.PodList{
				n1NodeName: {
					Items: []v1.Pod{
						// These won't be evicted.
						*test.BuildTestPod("p1", 400, 0, n1NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p2", 400, 0, n1NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p3", 400, 0, n1NodeName, test.SetRSOwnerRef),
					},
				},
				n2NodeName: {
					Items: []v1.Pod{
						// These won't be evicted.
						*test.BuildTestPod("p4", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p5", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p6", 400, 0, n2NodeName, test.SetRSOwnerRef),
					},
				},
				n3NodeName: {
					Items: []v1.Pod{
						// These won't be evicted.
						*test.BuildTestPod("p7", 400, 0, n3NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p8", 400, 0, n3NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p9", 400, 0, n3NodeName, test.SetRSOwnerRef),
					},
				},
			},
			maxPodsToEvictPerNode: 0,
			expectedPodsEvicted:   0,
		},
		{
			name: "no evictable pods",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU:  40,
				v1.ResourcePods: 40,
			},
			nodes: map[string]*v1.Node{
				n1NodeName: test.BuildTestNode(n1NodeName, 4000, 3000, 9, nil),
				n2NodeName: test.BuildTestNode(n2NodeName, 4000, 3000, 10, nil),
				n3NodeName: test.BuildTestNode(n3NodeName, 4000, 3000, 10, nil),
			},
			pods: map[string]*v1.PodList{
				n1NodeName: {
					Items: []v1.Pod{
						// These won't be evicted.
						*test.BuildTestPod("p1", 400, 0, n1NodeName, func(pod *v1.Pod) {
							// A pod with local storage.
							test.SetNormalOwnerRef(pod)
							pod.Spec.Volumes = []v1.Volume{
								{
									Name: "sample",
									VolumeSource: v1.VolumeSource{
										HostPath: &v1.HostPathVolumeSource{Path: "somePath"},
										EmptyDir: &v1.EmptyDirVolumeSource{
											SizeLimit: resource.NewQuantity(int64(10), resource.BinarySI)},
									},
								},
							}
							// A Mirror Pod.
							pod.Annotations = test.GetMirrorPodAnnotation()
						}),
						*test.BuildTestPod("p2", 400, 0, n1NodeName, func(pod *v1.Pod) {
							// A Critical Pod.
							pod.Namespace = "kube-system"
							priority := utils.SystemCriticalPriority
							pod.Spec.Priority = &priority
						}),
					},
				},
				n2NodeName: {
					Items: []v1.Pod{
						// These won't be evicted.
						*test.BuildTestPod("p3", 400, 0, n2NodeName, test.SetDSOwnerRef),
						*test.BuildTestPod("p4", 400, 0, n2NodeName, test.SetDSOwnerRef),
					},
				},
				n3NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p5", 400, 0, n3NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p6", 400, 0, n3NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p7", 400, 0, n3NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p8", 400, 0, n3NodeName, test.SetRSOwnerRef),
					},
				},
			},
			maxPodsToEvictPerNode: 0,
			expectedPodsEvicted:   0,
		},
		{
			name: "no node to schedule evicted pods",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU:  20,
				v1.ResourcePods: 20,
			},
			nodes: map[string]*v1.Node{
				n1NodeName: test.BuildTestNode(n1NodeName, 4000, 3000, 10, nil),
				n2NodeName: test.BuildTestNode(n2NodeName, 4000, 3000, 10, nil),
				n3NodeName: test.BuildTestNode(n3NodeName, 4000, 3000, 10, test.SetNodeUnschedulable),
			},
			pods: map[string]*v1.PodList{
				n1NodeName: {
					Items: []v1.Pod{
						// These can't be evicted.
						*test.BuildTestPod("p1", 400, 0, n1NodeName, test.SetRSOwnerRef),
					},
				},
				n2NodeName: {
					Items: []v1.Pod{
						// These can't be evicted.
						*test.BuildTestPod("p2", 400, 0, n2NodeName, test.SetRSOwnerRef),
					},
				},
				n3NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p3", 400, 0, n3NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p4", 400, 0, n3NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p5", 400, 0, n3NodeName, test.SetRSOwnerRef),
					},
				},
			},
			maxPodsToEvictPerNode: 0,
			expectedPodsEvicted:   0,
		},
		{
			name: "without priorities",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU:  30,
				v1.ResourcePods: 30,
			},
			nodes: map[string]*v1.Node{
				n1NodeName: test.BuildTestNode(n1NodeName, 4000, 3000, 10, nil),
				n2NodeName: test.BuildTestNode(n2NodeName, 4000, 3000, 10, nil),
				n3NodeName: test.BuildTestNode(n3NodeName, 4000, 3000, 10, test.SetNodeUnschedulable),
			},
			pods: map[string]*v1.PodList{
				n1NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p1", 400, 0, n1NodeName, test.SetRSOwnerRef),
						// These won't be evicted.
						*test.BuildTestPod("p2", 400, 0, n1NodeName, func(pod *v1.Pod) {
							// A Critical Pod.
							pod.Namespace = "kube-system"
							priority := utils.SystemCriticalPriority
							pod.Spec.Priority = &priority
						}),
					},
				},
				n2NodeName: {
					Items: []v1.Pod{
						// These won't be evicted.
						*test.BuildTestPod("p3", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p4", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p5", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p6", 400, 0, n2NodeName, test.SetRSOwnerRef),
					},
				},
				n3NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p7", 400, 0, n3NodeName, test.SetRSOwnerRef),
					},
				},
			},
			maxPodsToEvictPerNode: 0,
			expectedPodsEvicted:   2,
			evictedPods:           []string{"p1", "p7"},
		},
		{
			name: "without priorities stop when resource capacity is depleted",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU:  30,
				v1.ResourcePods: 30,
			},
			nodes: map[string]*v1.Node{
				n1NodeName: test.BuildTestNode(n1NodeName, 2000, 3000, 10, nil),
				n2NodeName: test.BuildTestNode(n2NodeName, 2000, 3000, 10, nil),
				n3NodeName: test.BuildTestNode(n3NodeName, 2000, 3000, 10, test.SetNodeUnschedulable),
			},
			pods: map[string]*v1.PodList{
				n1NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p1", 400, 0, n1NodeName, test.SetRSOwnerRef),
					},
				},
				n2NodeName: {
					Items: []v1.Pod{
						// These won't be evicted.
						*test.BuildTestPod("p2", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p3", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p4", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p5", 400, 0, n2NodeName, test.SetRSOwnerRef),
					},
				},
				n3NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p6", 400, 0, n3NodeName, test.SetRSOwnerRef),
					},
				},
			},
			maxPodsToEvictPerNode: 0,
			expectedPodsEvicted:   1,
		},
		{
			name: "with priorities",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU: 30,
			},
			nodes: map[string]*v1.Node{
				n1NodeName: test.BuildTestNode(n1NodeName, 4000, 3000, 10, nil),
				n2NodeName: test.BuildTestNode(n2NodeName, 2000, 3000, 10, nil),
				n3NodeName: test.BuildTestNode(n3NodeName, 2000, 3000, 10, test.SetNodeUnschedulable),
			},
			pods: map[string]*v1.PodList{
				n1NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p1", 400, 0, n1NodeName, func(pod *v1.Pod) {
							test.SetRSOwnerRef(pod)
							test.SetPodPriority(pod, lowPriority)
						}),
						*test.BuildTestPod("p2", 400, 0, n1NodeName, func(pod *v1.Pod) {
							test.SetRSOwnerRef(pod)
							test.SetPodPriority(pod, highPriority)
						}),
					},
				},
				n2NodeName: {
					Items: []v1.Pod{
						// These won't be evicted.
						*test.BuildTestPod("p5", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p6", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p7", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p8", 400, 0, n2NodeName, test.SetRSOwnerRef),
					},
				},
				n3NodeName: {
					Items: []v1.Pod{
						// These won't be evicted.
						*test.BuildTestPod("p9", 400, 0, n3NodeName, test.SetDSOwnerRef),
					},
				},
			},
			maxPodsToEvictPerNode: 0,
			expectedPodsEvicted:   1,
			evictedPods:           []string{"p1"},
		},
		{
			name: "without priorities evicting best-effort pods only",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU: 30,
			},
			nodes: map[string]*v1.Node{
				n1NodeName: test.BuildTestNode(n1NodeName, 3000, 3000, 10, nil),
				n2NodeName: test.BuildTestNode(n2NodeName, 3000, 3000, 5, nil),
				n3NodeName: test.BuildTestNode(n3NodeName, 3000, 3000, 10, test.SetNodeUnschedulable),
			},
			// All pods are assumed to be burstable (test.BuildTestNode always sets both cpu/memory resource requests to some value)
			pods: map[string]*v1.PodList{
				n1NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p1", 400, 0, n1NodeName, func(pod *v1.Pod) {
							test.SetRSOwnerRef(pod)
							test.MakeBestEffortPod(pod)
						}),
						*test.BuildTestPod("p2", 400, 0, n1NodeName, func(pod *v1.Pod) {
							test.SetRSOwnerRef(pod)
						}),
					},
				},
				n2NodeName: {
					Items: []v1.Pod{
						// These won't be evicted.
						*test.BuildTestPod("p3", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p4", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p5", 400, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p6", 400, 0, n2NodeName, test.SetRSOwnerRef),
					},
				},
				n3NodeName: {
					Items: []v1.Pod{},
				},
			},
			maxPodsToEvictPerNode: 0,
			expectedPodsEvicted:   1,
			evictedPods:           []string{"p1"},
		},
		{
			name: "with extended resource",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU:   20,
				extendedResource: 40,
			},
			nodes: map[string]*v1.Node{
				n1NodeName: test.BuildTestNode(n1NodeName, 4000, 3000, 10, func(node *v1.Node) {
					test.SetNodeExtendedResource(node, extendedResource, 8)
				}),
				n2NodeName: test.BuildTestNode(n2NodeName, 4000, 3000, 10, func(node *v1.Node) {
					test.SetNodeExtendedResource(node, extendedResource, 8)
				}),
				n3NodeName: test.BuildTestNode(n3NodeName, 4000, 3000, 10, test.SetNodeUnschedulable),
			},
			pods: map[string]*v1.PodList{
				n1NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p1", 100, 0, n1NodeName, func(pod *v1.Pod) {
							test.SetRSOwnerRef(pod)
							test.SetPodExtendedResourceRequest(pod, extendedResource, 1)
						}),
						*test.BuildTestPod("p2", 100, 0, n1NodeName, func(pod *v1.Pod) {
							test.SetRSOwnerRef(pod)
							test.SetPodExtendedResourceRequest(pod, extendedResource, 1)
						}),
						// These won't be evicted
						*test.BuildTestPod("p2", 100, 0, n1NodeName, func(pod *v1.Pod) {
							test.SetDSOwnerRef(pod)
							test.SetPodExtendedResourceRequest(pod, extendedResource, 1)
						}),
					},
				},
				n2NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p3", 500, 0, n2NodeName, func(pod *v1.Pod) {
							test.SetRSOwnerRef(pod)
							test.SetPodExtendedResourceRequest(pod, extendedResource, 1)
						}),
						*test.BuildTestPod("p4", 500, 0, n2NodeName, func(pod *v1.Pod) {
							test.SetRSOwnerRef(pod)
							test.SetPodExtendedResourceRequest(pod, extendedResource, 1)
						}),
						*test.BuildTestPod("p5", 500, 0, n2NodeName, func(pod *v1.Pod) {
							test.SetRSOwnerRef(pod)
							test.SetPodExtendedResourceRequest(pod, extendedResource, 1)
						}),
						*test.BuildTestPod("p6", 500, 0, n2NodeName, func(pod *v1.Pod) {
							test.SetRSOwnerRef(pod)
							test.SetPodExtendedResourceRequest(pod, extendedResource, 1)
						}),
					},
				},
				n3NodeName: {
					Items: []v1.Pod{},
				},
			},
			maxPodsToEvictPerNode: 0,
			expectedPodsEvicted:   2,
			evictedPods:           []string{"p1", "p2"},
		},
		{
			name: "with extended resource in some of nodes",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU:   40,
				extendedResource: 40,
			},
			nodes: map[string]*v1.Node{
				n1NodeName: test.BuildTestNode(n1NodeName, 4000, 3000, 10, func(node *v1.Node) {
					test.SetNodeExtendedResource(node, extendedResource, 8)
				}),
				n2NodeName: test.BuildTestNode(n2NodeName, 4000, 3000, 10, nil),
				n3NodeName: test.BuildTestNode(n3NodeName, 4000, 3000, 10, test.SetNodeUnschedulable),
			},
			pods: map[string]*v1.PodList{
				n1NodeName: {
					Items: []v1.Pod{
						//These won't be evicted
						*test.BuildTestPod("p1", 100, 0, n1NodeName, func(pod *v1.Pod) {
							test.SetRSOwnerRef(pod)
							test.SetPodExtendedResourceRequest(pod, extendedResource, 1)
						}),
						*test.BuildTestPod("p2", 100, 0, n1NodeName, func(pod *v1.Pod) {
							test.SetRSOwnerRef(pod)
							test.SetPodExtendedResourceRequest(pod, extendedResource, 1)
						}),
					},
				},
				n2NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p3", 500, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p4", 500, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p5", 500, 0, n2NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p6", 500, 0, n2NodeName, test.SetRSOwnerRef),
					},
				},
				n3NodeName: {
					Items: []v1.Pod{},
				},
			},
			maxPodsToEvictPerNode: 0,
			expectedPodsEvicted:   0,
		},
		{
			name: "Other node match pod node selector",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU:  30,
				v1.ResourcePods: 30,
			},
			nodes: map[string]*v1.Node{
				n1NodeName: test.BuildTestNode(n1NodeName, 4000, 3000, 9, func(node *v1.Node) {
					node.ObjectMeta.Labels = map[string]string{
						nodeSelectorKey: nodeSelectorValue,
					}
				}),
				n2NodeName: test.BuildTestNode(n2NodeName, 4000, 3000, 10, nil),
			},
			pods: map[string]*v1.PodList{
				n1NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p1", 400, 0, n1NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p2", 400, 0, n1NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p3", 400, 0, n1NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p4", 400, 0, n1NodeName, test.SetDSOwnerRef),
					},
				},
				n2NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p5", 400, 0, n2NodeName, func(pod *v1.Pod) {
							// A pod selecting nodes in the "west" datacenter
							test.SetRSOwnerRef(pod)
							pod.Spec.NodeSelector = map[string]string{
								nodeSelectorKey: nodeSelectorValue,
							}
						}),
					},
				},
			},
			maxPodsToEvictPerNode: 0,
			expectedPodsEvicted:   1,
		},
		{
			name: "Other node does not match pod node selector",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU:  30,
				v1.ResourcePods: 30,
			},
			nodes: map[string]*v1.Node{
				n1NodeName: test.BuildTestNode(n1NodeName, 4000, 3000, 9, nil),
				n2NodeName: test.BuildTestNode(n2NodeName, 4000, 3000, 10, nil),
			},
			pods: map[string]*v1.PodList{
				n1NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p1", 400, 0, n1NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p2", 400, 0, n1NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p3", 400, 0, n1NodeName, test.SetRSOwnerRef),
						*test.BuildTestPod("p4", 400, 0, n1NodeName, test.SetDSOwnerRef),
					},
				},
				n2NodeName: {
					Items: []v1.Pod{
						*test.BuildTestPod("p5", 400, 0, n2NodeName, func(pod *v1.Pod) {
							// A pod selecting nodes in the "west" datacenter
							test.SetRSOwnerRef(pod)
							pod.Spec.NodeSelector = map[string]string{
								nodeSelectorKey: nodeSelectorValue,
							}
						}),
					},
				},
			},
			maxPodsToEvictPerNode: 0,
			expectedPodsEvicted:   0,
		},
	}

	for _, test := range testCases {
		t.Run(test.name, func(t *testing.T) {
			fakeClient := &fake.Clientset{}
			fakeClient.Fake.AddReactor("list", "pods", func(action core.Action) (bool, runtime.Object, error) {
				list := action.(core.ListAction)
				fieldString := list.GetListRestrictions().Fields.String()
				if strings.Contains(fieldString, n1NodeName) {
					return true, test.pods[n1NodeName], nil
				}
				if strings.Contains(fieldString, n2NodeName) {
					return true, test.pods[n2NodeName], nil
				}
				if strings.Contains(fieldString, n3NodeName) {
					return true, test.pods[n3NodeName], nil
				}
				return true, nil, fmt.Errorf("Failed to list: %v", list)
			})
			fakeClient.Fake.AddReactor("get", "nodes", func(action core.Action) (bool, runtime.Object, error) {
				getAction := action.(core.GetAction)
				if node, exists := test.nodes[getAction.GetName()]; exists {
					return true, node, nil
				}
				return true, nil, fmt.Errorf("Wrong node: %v", getAction.GetName())
			})
			podsForEviction := make(map[string]struct{})
			for _, pod := range test.evictedPods {
				podsForEviction[pod] = struct{}{}
			}

			evictionFailed := false
			if len(test.evictedPods) > 0 {
				fakeClient.Fake.AddReactor("create", "pods", func(action core.Action) (bool, runtime.Object, error) {
					getAction := action.(core.CreateAction)
					obj := getAction.GetObject()
					if eviction, ok := obj.(*v1beta1.Eviction); ok {
						if _, exists := podsForEviction[eviction.Name]; exists {
							return true, obj, nil
						}
						evictionFailed = true
						return true, nil, fmt.Errorf("pod %q was unexpectedly evicted", eviction.Name)
					}
					return true, obj, nil
				})
			}

			var nodes []*v1.Node
			for _, node := range test.nodes {
				nodes = append(nodes, node)
			}

			podEvictor := evictions.NewPodEvictor(
				fakeClient,
				"v1",
				false,
				test.maxPodsToEvictPerNode,
				nodes,
				false,
				false,
				false,
			)

			strategy := api.DeschedulerStrategy{
				Enabled: true,
				Params: &api.StrategyParameters{
					NodeResourceUtilizationThresholds: &api.NodeResourceUtilizationThresholds{
						Thresholds: test.thresholds,
					},
					NodeFit: true,
				},
			}
			HighNodeUtilization(ctx, fakeClient, strategy, nodes, podEvictor)

			podsEvicted := podEvictor.TotalEvicted()
			if test.expectedPodsEvicted != podsEvicted {
				t.Errorf("Expected %#v pods to be evicted but %#v got evicted", test.expectedPodsEvicted, podsEvicted)
			}
			if evictionFailed {
				t.Errorf("Pod evictions failed unexpectedly")
			}
		})
	}
}

func TestValidateHighNodeUtilizationStrategyConfig(t *testing.T) {
	tests := []struct {
		name             string
		thresholds       api.ResourceThresholds
		targetThresholds api.ResourceThresholds
		errInfo          error
	}{
		{
			name: "passing target thresholds",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU:    20,
				v1.ResourceMemory: 20,
			},
			targetThresholds: api.ResourceThresholds{
				v1.ResourceCPU:    80,
				v1.ResourceMemory: 80,
			},
			errInfo: fmt.Errorf("targetThresholds is not applicable for HighNodeUtilization"),
		},
		{
			name:       "passing empty thresholds",
			thresholds: api.ResourceThresholds{},
			errInfo:    fmt.Errorf("thresholds config is not valid: no resource threshold is configured"),
		},
		{
			name: "passing invalid thresholds",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU:    80,
				v1.ResourceMemory: 120,
			},
			errInfo: fmt.Errorf("thresholds config is not valid: %v", fmt.Errorf(
				"%v threshold not in [%v, %v] range", v1.ResourceMemory, MinResourcePercentage, MaxResourcePercentage)),
		},
		{
			name: "passing valid strategy config",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU:    80,
				v1.ResourceMemory: 80,
			},
			errInfo: nil,
		},
		{
			name: "passing valid strategy config with extended resource",
			thresholds: api.ResourceThresholds{
				v1.ResourceCPU:    80,
				v1.ResourceMemory: 80,
				extendedResource:  80,
			},
			errInfo: nil,
		},
	}

	for _, testCase := range tests {
		validateErr := validateHighUtilizationStrategyConfig(testCase.thresholds, testCase.targetThresholds)

		if validateErr == nil || testCase.errInfo == nil {
			if validateErr != testCase.errInfo {
				t.Errorf("expected validity of strategy config: thresholds %#v targetThresholds %#v to be %v but got %v instead",
					testCase.thresholds, testCase.targetThresholds, testCase.errInfo, validateErr)
			}
		} else if validateErr.Error() != testCase.errInfo.Error() {
			t.Errorf("expected validity of strategy config: thresholds %#v targetThresholds %#v to be %v but got %v instead",
				testCase.thresholds, testCase.targetThresholds, testCase.errInfo, validateErr)
		}
	}
}

func TestHighNodeUtilizationWithTaints(t *testing.T) {
	ctx := context.Background()
	strategy := api.DeschedulerStrategy{
		Enabled: true,
		Params: &api.StrategyParameters{
			NodeResourceUtilizationThresholds: &api.NodeResourceUtilizationThresholds{
				Thresholds: api.ResourceThresholds{
					v1.ResourceCPU: 40,
				},
			},
		},
	}

	n1 := test.BuildTestNode("n1", 1000, 3000, 10, nil)
	n2 := test.BuildTestNode("n2", 1000, 3000, 10, nil)
	n3 := test.BuildTestNode("n3", 1000, 3000, 10, nil)
	n3withTaints := n3.DeepCopy()
	n3withTaints.Spec.Taints = []v1.Taint{
		{
			Key:    "key",
			Value:  "value",
			Effect: v1.TaintEffectNoSchedule,
		},
	}

	podThatToleratesTaint := test.BuildTestPod("tolerate_pod", 200, 0, n1.Name, test.SetRSOwnerRef)
	podThatToleratesTaint.Spec.Tolerations = []v1.Toleration{
		{
			Key:   "key",
			Value: "value",
		},
	}

	tests := []struct {
		name              string
		nodes             []*v1.Node
		pods              []*v1.Pod
		evictionsExpected int
	}{
		{
			name:  "No taints",
			nodes: []*v1.Node{n1, n2, n3},
			pods: []*v1.Pod{
				//Node 1 pods
				test.BuildTestPod(fmt.Sprintf("pod_1_%s", n1.Name), 200, 0, n1.Name, test.SetRSOwnerRef),
				test.BuildTestPod(fmt.Sprintf("pod_2_%s", n1.Name), 200, 0, n1.Name, test.SetRSOwnerRef),
				test.BuildTestPod(fmt.Sprintf("pod_3_%s", n1.Name), 200, 0, n1.Name, test.SetRSOwnerRef),
				// Node 2 pods
				test.BuildTestPod(fmt.Sprintf("pod_4_%s", n2.Name), 200, 0, n2.Name, test.SetRSOwnerRef),
			},
			evictionsExpected: 1,
		},
		{
			name:  "No pod tolerates node taint",
			nodes: []*v1.Node{n1, n3withTaints},
			pods: []*v1.Pod{
				//Node 1 pods
				test.BuildTestPod(fmt.Sprintf("pod_1_%s", n1.Name), 200, 0, n1.Name, test.SetRSOwnerRef),
				// Node 3 pods
				test.BuildTestPod(fmt.Sprintf("pod_2_%s", n3withTaints.Name), 200, 0, n3withTaints.Name, test.SetRSOwnerRef),
			},
			evictionsExpected: 0,
		},
		{
			name:  "Pod which tolerates node taint",
			nodes: []*v1.Node{n1, n3withTaints},
			pods: []*v1.Pod{
				//Node 1 pods
				test.BuildTestPod(fmt.Sprintf("pod_1_%s", n1.Name), 100, 0, n1.Name, test.SetRSOwnerRef),
				podThatToleratesTaint,
				// Node 3 pods
				test.BuildTestPod(fmt.Sprintf("pod_9_%s", n3withTaints.Name), 500, 0, n3withTaints.Name, test.SetRSOwnerRef),
			},
			evictionsExpected: 1,
		},
	}

	for _, item := range tests {
		t.Run(item.name, func(t *testing.T) {
			var objs []runtime.Object
			for _, node := range item.nodes {
				objs = append(objs, node)
			}

			for _, pod := range item.pods {
				objs = append(objs, pod)
			}

			fakeClient := fake.NewSimpleClientset(objs...)

			podEvictor := evictions.NewPodEvictor(
				fakeClient,
				"policy/v1",
				false,
				item.evictionsExpected,
				item.nodes,
				false,
				false,
				false,
			)

			HighNodeUtilization(ctx, fakeClient, strategy, item.nodes, podEvictor)

			if item.evictionsExpected != podEvictor.TotalEvicted() {
				t.Errorf("Expected %v evictions, got %v", item.evictionsExpected, podEvictor.TotalEvicted())
			}
		})
	}
}