/*
Copyright 2019 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 cpumanager

import (
	"reflect"
	"sort"
	"testing"

	cadvisorapi "github.com/google/cadvisor/info/v1"
	v1 "k8s.io/api/core/v1"
	"k8s.io/apimachinery/pkg/types"
	"k8s.io/kubernetes/pkg/kubelet/cm/cpumanager/state"
	"k8s.io/kubernetes/pkg/kubelet/cm/cpumanager/topology"
	"k8s.io/kubernetes/pkg/kubelet/cm/cpuset"
	"k8s.io/kubernetes/pkg/kubelet/cm/topologymanager"
	"k8s.io/kubernetes/pkg/kubelet/cm/topologymanager/bitmask"
)

func TestGetTopologyHints(t *testing.T) {
	testPod1 := makePod("fakePod", "fakeContainer", "2", "2")
	testContainer1 := &testPod1.Spec.Containers[0]
	testPod2 := makePod("fakePod", "fakeContainer", "5", "5")
	testContainer2 := &testPod2.Spec.Containers[0]
	testPod3 := makePod("fakePod", "fakeContainer", "7", "7")
	testContainer3 := &testPod3.Spec.Containers[0]
	testPod4 := makePod("fakePod", "fakeContainer", "11", "11")
	testContainer4 := &testPod4.Spec.Containers[0]

	firstSocketMask, _ := bitmask.NewBitMask(0)
	secondSocketMask, _ := bitmask.NewBitMask(1)
	crossSocketMask, _ := bitmask.NewBitMask(0, 1)

	machineInfo := cadvisorapi.MachineInfo{
		NumCores: 12,
		Topology: []cadvisorapi.Node{
			{Id: 0,
				Cores: []cadvisorapi.Core{
					{Id: 0, Threads: []int{0, 6}},
					{Id: 1, Threads: []int{1, 7}},
					{Id: 2, Threads: []int{2, 8}},
				},
			},
			{Id: 1,
				Cores: []cadvisorapi.Core{
					{Id: 0, Threads: []int{3, 9}},
					{Id: 1, Threads: []int{4, 10}},
					{Id: 2, Threads: []int{5, 11}},
				},
			},
		},
	}

	numaNodeInfo := topology.NUMANodeInfo{
		0: cpuset.NewCPUSet(0, 6, 1, 7, 2, 8),
		1: cpuset.NewCPUSet(3, 9, 4, 10, 5, 11),
	}

	tcases := []struct {
		name          string
		pod           v1.Pod
		container     v1.Container
		assignments   state.ContainerCPUAssignments
		defaultCPUSet cpuset.CPUSet
		expectedHints []topologymanager.TopologyHint
	}{
		{
			name:          "Request 2 CPUs, 4 available on NUMA 0, 6 available on NUMA 1",
			pod:           *testPod1,
			container:     *testContainer1,
			defaultCPUSet: cpuset.NewCPUSet(2, 3, 4, 5, 6, 7, 8, 9, 10, 11),
			expectedHints: []topologymanager.TopologyHint{
				{
					NUMANodeAffinity: firstSocketMask,
					Preferred:        true,
				},
				{
					NUMANodeAffinity: secondSocketMask,
					Preferred:        true,
				},
				{
					NUMANodeAffinity: crossSocketMask,
					Preferred:        false,
				},
			},
		},
		{
			name:          "Request 5 CPUs, 4 available on NUMA 0, 6 available on NUMA 1",
			pod:           *testPod2,
			container:     *testContainer2,
			defaultCPUSet: cpuset.NewCPUSet(2, 3, 4, 5, 6, 7, 8, 9, 10, 11),
			expectedHints: []topologymanager.TopologyHint{
				{
					NUMANodeAffinity: secondSocketMask,
					Preferred:        true,
				},
				{
					NUMANodeAffinity: crossSocketMask,
					Preferred:        false,
				},
			},
		},
		{
			name:          "Request 7 CPUs, 4 available on NUMA 0, 6 available on NUMA 1",
			pod:           *testPod3,
			container:     *testContainer3,
			defaultCPUSet: cpuset.NewCPUSet(2, 3, 4, 5, 6, 7, 8, 9, 10, 11),
			expectedHints: []topologymanager.TopologyHint{
				{
					NUMANodeAffinity: crossSocketMask,
					Preferred:        true,
				},
			},
		},
		{
			name:          "Request 11 CPUs, 4 available on NUMA 0, 6 available on NUMA 1",
			pod:           *testPod4,
			container:     *testContainer4,
			defaultCPUSet: cpuset.NewCPUSet(2, 3, 4, 5, 6, 7, 8, 9, 10, 11),
			expectedHints: nil,
		},
		{
			name:          "Request 2 CPUs, 1 available on NUMA 0, 1 available on NUMA 1",
			pod:           *testPod1,
			container:     *testContainer1,
			defaultCPUSet: cpuset.NewCPUSet(0, 3),
			expectedHints: []topologymanager.TopologyHint{
				{
					NUMANodeAffinity: crossSocketMask,
					Preferred:        false,
				},
			},
		},
		{
			name:          "Request more CPUs than available",
			pod:           *testPod2,
			container:     *testContainer2,
			defaultCPUSet: cpuset.NewCPUSet(0, 1, 2, 3),
			expectedHints: nil,
		},
		{
			name:      "Regenerate Single-Node NUMA Hints if already allocated 1/2",
			pod:       *testPod1,
			container: *testContainer1,
			assignments: state.ContainerCPUAssignments{
				string(testPod1.UID): map[string]cpuset.CPUSet{
					testContainer1.Name: cpuset.NewCPUSet(0, 6),
				},
			},
			defaultCPUSet: cpuset.NewCPUSet(),
			expectedHints: []topologymanager.TopologyHint{
				{
					NUMANodeAffinity: firstSocketMask,
					Preferred:        true,
				},
				{
					NUMANodeAffinity: crossSocketMask,
					Preferred:        false,
				},
			},
		},
		{
			name:      "Regenerate Single-Node NUMA Hints if already allocated 1/2",
			pod:       *testPod1,
			container: *testContainer1,
			assignments: state.ContainerCPUAssignments{
				string(testPod1.UID): map[string]cpuset.CPUSet{
					testContainer1.Name: cpuset.NewCPUSet(3, 9),
				},
			},
			defaultCPUSet: cpuset.NewCPUSet(),
			expectedHints: []topologymanager.TopologyHint{
				{
					NUMANodeAffinity: secondSocketMask,
					Preferred:        true,
				},
				{
					NUMANodeAffinity: crossSocketMask,
					Preferred:        false,
				},
			},
		},
		{
			name:      "Regenerate Cross-NUMA Hints if already allocated",
			pod:       *testPod4,
			container: *testContainer4,
			assignments: state.ContainerCPUAssignments{
				string(testPod4.UID): map[string]cpuset.CPUSet{
					testContainer4.Name: cpuset.NewCPUSet(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10),
				},
			},
			defaultCPUSet: cpuset.NewCPUSet(),
			expectedHints: []topologymanager.TopologyHint{
				{
					NUMANodeAffinity: crossSocketMask,
					Preferred:        true,
				},
			},
		},
		{
			name:      "Requested less than already allocated",
			pod:       *testPod1,
			container: *testContainer1,
			assignments: state.ContainerCPUAssignments{
				string(testPod1.UID): map[string]cpuset.CPUSet{
					testContainer1.Name: cpuset.NewCPUSet(0, 6, 3, 9),
				},
			},
			defaultCPUSet: cpuset.NewCPUSet(),
			expectedHints: []topologymanager.TopologyHint{},
		},
		{
			name:      "Requested more than already allocated",
			pod:       *testPod4,
			container: *testContainer4,
			assignments: state.ContainerCPUAssignments{
				string(testPod4.UID): map[string]cpuset.CPUSet{
					testContainer4.Name: cpuset.NewCPUSet(0, 6, 3, 9),
				},
			},
			defaultCPUSet: cpuset.NewCPUSet(),
			expectedHints: []topologymanager.TopologyHint{},
		},
	}
	for _, tc := range tcases {
		topology, _ := topology.Discover(&machineInfo, numaNodeInfo)

		var activePods []*v1.Pod
		for p := range tc.assignments {
			pod := v1.Pod{}
			pod.UID = types.UID(p)
			for c := range tc.assignments[p] {
				container := v1.Container{}
				container.Name = c
				pod.Spec.Containers = append(pod.Spec.Containers, container)
			}
			activePods = append(activePods, &pod)
		}

		m := manager{
			policy: &staticPolicy{
				topology: topology,
			},
			state: &mockState{
				assignments:   tc.assignments,
				defaultCPUSet: tc.defaultCPUSet,
			},
			topology:          topology,
			activePods:        func() []*v1.Pod { return activePods },
			podStatusProvider: mockPodStatusProvider{},
			sourcesReady:      &sourcesReadyStub{},
		}

		hints := m.GetTopologyHints(&tc.pod, &tc.container)[string(v1.ResourceCPU)]
		if len(tc.expectedHints) == 0 && len(hints) == 0 {
			continue
		}
		sort.SliceStable(hints, func(i, j int) bool {
			return hints[i].LessThan(hints[j])
		})
		sort.SliceStable(tc.expectedHints, func(i, j int) bool {
			return tc.expectedHints[i].LessThan(tc.expectedHints[j])
		})
		if !reflect.DeepEqual(tc.expectedHints, hints) {
			t.Errorf("Expected in result to be %v , got %v", tc.expectedHints, hints)
		}
	}
}