/*
Copyright 2021 Alibaba Group Holding Limited.

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 selector

import (
	"fmt"
	"testing"

	"github.com/onsi/gomega"
	corev1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"

	"github.com/alibaba/polardbx-operator/pkg/util/json"
)

var node = &corev1.Node{
	TypeMeta: metav1.TypeMeta{
		Kind: "Node",
	},
	ObjectMeta: metav1.ObjectMeta{
		Name: "test-node",
		Labels: map[string]string{
			"a": "a",
		},
		Generation: 10,
	},
	Status: corev1.NodeStatus{
		Phase: corev1.NodeRunning,
		NodeInfo: corev1.NodeSystemInfo{
			KernelVersion: "3.19",
		},
		Config: nil,
	},
}

func BenchmarkGetStringValueOfField(b *testing.B) {
	for i := 0; i < b.N; i++ {
		_, _ = json.GetStringValueOfFieldByJsonKey(node, "metadata.name")
	}
}

func TestIsFieldsMatchesRequirement(t *testing.T) {
	testcases := map[string]struct {
		requirement *corev1.NodeSelectorRequirement
		expected    bool
		err         error
	}{
		"node-name-should-match": {
			requirement: &corev1.NodeSelectorRequirement{
				Key:      "metadata.name",
				Operator: "In",
				Values: []string{
					"test-node",
				},
			},
			expected: true,
		},
		"node-name-should-not-match": {
			requirement: &corev1.NodeSelectorRequirement{
				Key:      "metadata.name",
				Operator: "In",
				Values:   []string{},
			},
			expected: false,
		},
		"node-label-exists-should-match": {
			requirement: &corev1.NodeSelectorRequirement{
				Key:      "metadata.labels.a",
				Operator: "Exists",
			},
			expected: true,
		},
		"node-label-exists-should-not-match": {
			requirement: &corev1.NodeSelectorRequirement{
				Key:      "metadata.labels.a",
				Operator: "DoesNotExist",
			},
			expected: false,
		},
		"node-label-not-exists-should-not-match": {
			requirement: &corev1.NodeSelectorRequirement{
				Key:      "metadata.labels.b",
				Operator: "Exists",
			},
			expected: false,
		},
		"node-label-not-exists-should-match": {
			requirement: &corev1.NodeSelectorRequirement{
				Key:      "metadata.labels.b",
				Operator: "DoesNotExist",
			},
			expected: true,
		},
		"node-generation-gt-9-should-match": {
			requirement: &corev1.NodeSelectorRequirement{
				Key:      "metadata.generation",
				Operator: "Gt",
				Values:   []string{"9"},
			},
			expected: true,
		},
		"node-generation-lt-11-should-match": {
			requirement: &corev1.NodeSelectorRequirement{
				Key:      "metadata.generation",
				Operator: "Lt",
				Values:   []string{"11"},
			},
			expected: true,
		},
		"node-generation-gt-10-should-not-match": {
			requirement: &corev1.NodeSelectorRequirement{
				Key:      "metadata.generation",
				Operator: "Gt",
				Values:   []string{"10"},
			},
			expected: false,
		},
		"node-generation-lt-9-should-not-match": {
			requirement: &corev1.NodeSelectorRequirement{
				Key:      "metadata.generation",
				Operator: "Lt",
				Values:   []string{"9"},
			},
			expected: false,
		},
	}

	for name, tc := range testcases {
		t.Run(name, func(t *testing.T) {
			g := gomega.NewGomegaWithT(t)

			matches, err := IsFieldsMatchesRequirement(node, tc.requirement)
			if err != nil {
				g.Expect(err).To(gomega.Equal(tc.err))
			} else {
				g.Expect(matches).To(gomega.Equal(tc.expected))
			}
		})
	}
}

func TestGetStringValueOfField(t *testing.T) {
	testcases := map[string]struct {
		node        *corev1.Node
		labelKey    string
		expected    string
		expectedErr error
	}{
		"empty-node": {
			node:        nil,
			labelKey:    "metadata.name",
			expectedErr: json.ErrNilOrNotExists,
		},
		"inline-kind": {
			node:     node,
			labelKey: "kind",
			expected: "Node",
		},
		"metadata.name": {
			node:     node,
			expected: "test-node",
		},
		"metadata.labels.a": {
			node:     node,
			expected: "a",
		},
		"metadata.labels.b": {
			node:        node,
			expectedErr: json.ErrNilOrNotExists,
		},
		"metadata.namespace": {
			node:     node,
			expected: "",
		},
		"status.phase": {
			node:     node,
			expected: "Running",
		},
		"status.nodeInfo.kernelVersion": {
			node:     node,
			expected: "3.19",
		},
		"status.config": {
			node:        node,
			expectedErr: json.ErrNilOrNotExists,
		},
	}

	for name, tc := range testcases {
		t.Run(name, func(t *testing.T) {
			g := gomega.NewGomegaWithT(t)
			labelKey := tc.labelKey
			if len(labelKey) == 0 {
				labelKey = name
			}
			val, err := json.GetStringValueOfFieldByJsonKey(tc.node, labelKey)
			if err != nil {
				if err == json.ErrInvalidField {
					fmt.Println("not a valid field: " + labelKey)
				} else if err == json.ErrNilOrNotExists {
					fmt.Println("field not found: " + labelKey)
				} else {
					fmt.Println("unexpected error: " + err.Error())
				}
				g.Expect(err).To(gomega.Equal(tc.expectedErr))
			} else {
				fmt.Printf("value of field \"%s\": %s\n", labelKey, val)
				g.Expect(val).To(gomega.Equal(tc.expected))
			}
		})
	}
}

func TestIsNodeMatches(t *testing.T) {
	testcases := map[string]struct {
		nodeSelector *corev1.NodeSelector
		expected     bool
	}{
		"label-not-match-should-not-match": {
			expected: false,
			nodeSelector: &corev1.NodeSelector{
				NodeSelectorTerms: []corev1.NodeSelectorTerm{
					{
						MatchExpressions: []corev1.NodeSelectorRequirement{
							{
								Key:      "b",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
				},
			},
		},
		"label-match-should-match": {
			expected: true,
			nodeSelector: &corev1.NodeSelector{
				NodeSelectorTerms: []corev1.NodeSelectorTerm{
					{
						MatchExpressions: []corev1.NodeSelectorRequirement{
							{
								Key:      "a",
								Operator: corev1.NodeSelectorOpIn,
								Values:   []string{"a"},
							},
						},
					},
				},
			},
		},
		"label-not-match-but-name-match-should-match": {
			expected: true,
			nodeSelector: &corev1.NodeSelector{
				NodeSelectorTerms: []corev1.NodeSelectorTerm{
					{
						MatchExpressions: []corev1.NodeSelectorRequirement{
							{
								Key:      "b",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "metadata.name",
								Operator: corev1.NodeSelectorOpIn,
								Values:   []string{"test-node"},
							},
						},
					},
				},
			},
		},
	}

	for name, tc := range testcases {
		t.Run(name, func(t *testing.T) {
			g := gomega.NewGomegaWithT(t)

			matches, err := IsNodeMatches(node, tc.nodeSelector)
			g.Expect(err).Should(gomega.BeNil())
			g.Expect(matches).To(gomega.Equal(tc.expected))
		})
	}
}

func TestDoesNodeSelectorCoversAnother(t *testing.T) {
	testcases := map[string]struct {
		a      *corev1.NodeSelector
		b      *corev1.NodeSelector
		expect bool
	}{
		"single-term-covers": {
			a: &corev1.NodeSelector{
				NodeSelectorTerms: []corev1.NodeSelectorTerm{
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "host",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
				},
			},
			b: &corev1.NodeSelector{
				NodeSelectorTerms: []corev1.NodeSelectorTerm{
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "host",
								Operator: corev1.NodeSelectorOpExists,
							},
							{
								Key:      "domain",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
				},
			},
			expect: true,
		},
		"single-term-not-covers": {
			a: &corev1.NodeSelector{
				NodeSelectorTerms: []corev1.NodeSelectorTerm{
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "host",
								Operator: corev1.NodeSelectorOpExists,
							},
							{
								Key:      "domain",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
				},
			},
			b: &corev1.NodeSelector{
				NodeSelectorTerms: []corev1.NodeSelectorTerm{
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "host",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
				},
			},
			expect: false,
		},
		"left-nil-right-nil": {
			expect: true,
		},
		"left-nil-right-non-nil": {
			a: nil,
			b: &corev1.NodeSelector{
				NodeSelectorTerms: []corev1.NodeSelectorTerm{
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "host",
								Operator: corev1.NodeSelectorOpExists,
							},
							{
								Key:      "domain",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
				},
			},
			expect: true,
		},
		"multi-terms-covers": {
			a: &corev1.NodeSelector{
				NodeSelectorTerms: []corev1.NodeSelectorTerm{
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "host",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "domain",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
				},
			},
			b: &corev1.NodeSelector{
				NodeSelectorTerms: []corev1.NodeSelectorTerm{
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "host",
								Operator: corev1.NodeSelectorOpExists,
							},
							{
								Key:      "zone",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "domain",
								Operator: corev1.NodeSelectorOpExists,
							},
							{
								Key:      "zone",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
				},
			},
			expect: true,
		},
		"multi-terms-not-covers": {
			a: &corev1.NodeSelector{
				NodeSelectorTerms: []corev1.NodeSelectorTerm{
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "host",
								Operator: corev1.NodeSelectorOpExists,
							},
							{
								Key:      "zone",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "domain",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
				},
			},
			b: &corev1.NodeSelector{
				NodeSelectorTerms: []corev1.NodeSelectorTerm{
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "host",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
					{
						MatchFields: []corev1.NodeSelectorRequirement{
							{
								Key:      "domain",
								Operator: corev1.NodeSelectorOpExists,
							},
							{
								Key:      "zone",
								Operator: corev1.NodeSelectorOpExists,
							},
						},
					},
				},
			},
			expect: false,
		},
	}

	for name, tc := range testcases {
		t.Run(name, func(t *testing.T) {
			if tc.expect != DoesNodeSelectorCoversAnother(tc.a, tc.b) {
				t.Fatal("not match: " + name)
			}
		})
	}
}