/*
Copyright 2017 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 reconcilers

/*
Original Source:
https://github.com/openshift/origin/blob/bb340c5dd5ff72718be86fb194dedc0faed7f4c7/pkg/cmd/server/election/lease_endpoint_reconciler_test.go
*/

import (
	"testing"

	corev1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/client-go/kubernetes/fake"
	netutils "k8s.io/utils/net"
)

type fakeLeases struct {
	keys map[string]bool
}

var _ Leases = &fakeLeases{}

func newFakeLeases() *fakeLeases {
	return &fakeLeases{make(map[string]bool)}
}

func (f *fakeLeases) ListLeases() ([]string, error) {
	res := make([]string, 0, len(f.keys))
	for ip := range f.keys {
		res = append(res, ip)
	}
	return res, nil
}

func (f *fakeLeases) UpdateLease(ip string) error {
	f.keys[ip] = true
	return nil
}

func (f *fakeLeases) RemoveLease(ip string) error {
	delete(f.keys, ip)
	return nil
}

func (f *fakeLeases) SetKeys(keys []string) {
	for _, ip := range keys {
		f.keys[ip] = false
	}
}

func (f *fakeLeases) GetUpdatedKeys() []string {
	res := []string{}
	for ip, updated := range f.keys {
		if updated {
			res = append(res, ip)
		}
	}
	return res
}

func (f *fakeLeases) Destroy() {
}

func TestLeaseEndpointReconciler(t *testing.T) {
	reconcileTests := []struct {
		testName      string
		serviceName   string
		ip            string
		endpointPorts []corev1.EndpointPort
		endpointKeys  []string
		initialState  []runtime.Object
		expectUpdate  []runtime.Object
		expectCreate  []runtime.Object
	}{
		{
			testName:      "no existing endpoints",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			initialState:  nil,
			expectCreate:  makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "existing endpoints satisfy",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			initialState:  makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "existing endpoints satisfy, no endpointslice",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			initialState: []runtime.Object{
				makeEndpoints("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			},
			expectCreate: []runtime.Object{
				makeEndpointSlice("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			},
		},
		{
			testName:      "existing endpointslice satisfies, no endpoints",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			initialState: []runtime.Object{
				makeEndpointSlice("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			},
			expectCreate: []runtime.Object{
				makeEndpoints("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			},
		},
		{
			testName:      "existing endpoints satisfy, endpointslice is wrong",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			initialState: []runtime.Object{
				makeEndpoints("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
				makeEndpointSlice("foo", []string{"4.3.2.1"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			},
			expectUpdate: []runtime.Object{
				makeEndpointSlice("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			},
		},
		{
			testName:      "existing endpointslice satisfies, endpoints is wrong",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			initialState: []runtime.Object{
				makeEndpoints("foo", []string{"4.3.2.1"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
				makeEndpointSlice("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			},
			expectUpdate: []runtime.Object{
				makeEndpoints("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			},
		},
		{
			testName:      "existing endpoints satisfy + refresh existing key",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			endpointKeys:  []string{"1.2.3.4"},
			initialState:  makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "existing endpoints satisfy but too many",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			initialState:  makeEndpointsArray("foo", []string{"1.2.3.4", "4.3.2.1"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			expectUpdate:  makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "existing endpoints satisfy but too many + extra masters",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			endpointKeys:  []string{"1.2.3.4", "4.3.2.2", "4.3.2.3", "4.3.2.4"},
			initialState:  makeEndpointsArray("foo", []string{"1.2.3.4", "4.3.2.1", "4.3.2.2", "4.3.2.3", "4.3.2.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			expectUpdate:  makeEndpointsArray("foo", []string{"1.2.3.4", "4.3.2.2", "4.3.2.3", "4.3.2.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "existing endpoints satisfy but too many + extra masters + delete first",
			serviceName:   "foo",
			ip:            "4.3.2.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			endpointKeys:  []string{"4.3.2.1", "4.3.2.2", "4.3.2.3", "4.3.2.4"},
			initialState:  makeEndpointsArray("foo", []string{"1.2.3.4", "4.3.2.1", "4.3.2.2", "4.3.2.3", "4.3.2.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			expectUpdate:  makeEndpointsArray("foo", []string{"4.3.2.1", "4.3.2.2", "4.3.2.3", "4.3.2.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "existing endpoints current IP missing",
			serviceName:   "foo",
			ip:            "4.3.2.2",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			endpointKeys:  []string{"4.3.2.1"},
			initialState:  makeEndpointsArray("foo", []string{"4.3.2.1"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			expectUpdate:  makeEndpointsArray("foo", []string{"4.3.2.1", "4.3.2.2"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "existing endpoints wrong name",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			initialState:  makeEndpointsArray("bar", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			expectCreate:  makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "existing endpoints wrong IP",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			initialState:  makeEndpointsArray("foo", []string{"4.3.2.1"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			expectUpdate:  makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "existing endpoints wrong port",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			initialState:  makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 9090, Protocol: "TCP"}}),
			expectUpdate:  makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "existing endpoints wrong protocol",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			initialState:  makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "UDP"}}),
			expectUpdate:  makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "existing endpoints wrong port name",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "baz", Port: 8080, Protocol: "TCP"}},
			initialState:  makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			expectUpdate:  makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "baz", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "existing endpoints without skip mirror label",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			initialState: []runtime.Object{
				// can't use makeEndpointsArray() here because we don't want the
				// skip-mirror label
				&corev1.Endpoints{
					ObjectMeta: metav1.ObjectMeta{
						Namespace: metav1.NamespaceDefault,
						Name:      "foo",
					},
					Subsets: []corev1.EndpointSubset{{
						Addresses: []corev1.EndpointAddress{{IP: "1.2.3.4"}},
						Ports:     []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
					}},
				},
				makeEndpointSlice("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			},
			expectUpdate: []runtime.Object{
				makeEndpoints("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
				// EndpointSlice does not get updated because it was already correct
			},
		},
		{
			testName:    "existing endpoints extra service ports satisfy",
			serviceName: "foo",
			ip:          "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{
				{Name: "foo", Port: 8080, Protocol: "TCP"},
				{Name: "bar", Port: 1000, Protocol: "TCP"},
				{Name: "baz", Port: 1010, Protocol: "TCP"},
			},
			initialState: makeEndpointsArray("foo", []string{"1.2.3.4"},
				[]corev1.EndpointPort{
					{Name: "foo", Port: 8080, Protocol: "TCP"},
					{Name: "bar", Port: 1000, Protocol: "TCP"},
					{Name: "baz", Port: 1010, Protocol: "TCP"},
				},
			),
		},
		{
			testName:    "existing endpoints extra service ports missing port",
			serviceName: "foo",
			ip:          "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{
				{Name: "foo", Port: 8080, Protocol: "TCP"},
				{Name: "bar", Port: 1000, Protocol: "TCP"},
			},
			initialState: makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			expectUpdate: makeEndpointsArray("foo", []string{"1.2.3.4"},
				[]corev1.EndpointPort{
					{Name: "foo", Port: 8080, Protocol: "TCP"},
					{Name: "bar", Port: 1000, Protocol: "TCP"},
				},
			),
		},
	}
	for _, test := range reconcileTests {
		t.Run(test.testName, func(t *testing.T) {
			fakeLeases := newFakeLeases()
			fakeLeases.SetKeys(test.endpointKeys)
			clientset := fake.NewSimpleClientset(test.initialState...)

			epAdapter := NewEndpointsAdapter(clientset.CoreV1(), clientset.DiscoveryV1())
			r := NewLeaseEndpointReconciler(epAdapter, fakeLeases)
			err := r.ReconcileEndpoints(test.serviceName, netutils.ParseIPSloppy(test.ip), test.endpointPorts, true)
			if err != nil {
				t.Errorf("unexpected error reconciling: %v", err)
			}

			err = verifyCreatesAndUpdates(clientset, test.expectCreate, test.expectUpdate)
			if err != nil {
				t.Errorf("unexpected error in side effects: %v", err)
			}

			if updatedKeys := fakeLeases.GetUpdatedKeys(); len(updatedKeys) != 1 || updatedKeys[0] != test.ip {
				t.Errorf("expected the master's IP to be refreshed, but the following IPs were refreshed instead: %v", updatedKeys)
			}
		})
	}

	nonReconcileTests := []struct {
		testName      string
		serviceName   string
		ip            string
		endpointPorts []corev1.EndpointPort
		endpointKeys  []string
		initialState  []runtime.Object
		expectUpdate  []runtime.Object
		expectCreate  []runtime.Object
	}{
		{
			testName:    "existing endpoints extra service ports missing port no update",
			serviceName: "foo",
			ip:          "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{
				{Name: "foo", Port: 8080, Protocol: "TCP"},
				{Name: "bar", Port: 1000, Protocol: "TCP"},
			},
			initialState: makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			expectUpdate: nil,
		},
		{
			testName:    "existing endpoints extra service ports, wrong ports, wrong IP",
			serviceName: "foo",
			ip:          "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{
				{Name: "foo", Port: 8080, Protocol: "TCP"},
				{Name: "bar", Port: 1000, Protocol: "TCP"},
			},
			initialState: makeEndpointsArray("foo", []string{"4.3.2.1"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			expectUpdate: makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "no existing endpoints",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			initialState:  nil,
			expectCreate:  makeEndpointsArray("foo", []string{"1.2.3.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
	}
	for _, test := range nonReconcileTests {
		t.Run(test.testName, func(t *testing.T) {
			fakeLeases := newFakeLeases()
			fakeLeases.SetKeys(test.endpointKeys)
			clientset := fake.NewSimpleClientset(test.initialState...)
			epAdapter := NewEndpointsAdapter(clientset.CoreV1(), clientset.DiscoveryV1())
			r := NewLeaseEndpointReconciler(epAdapter, fakeLeases)
			err := r.ReconcileEndpoints(test.serviceName, netutils.ParseIPSloppy(test.ip), test.endpointPorts, false)
			if err != nil {
				t.Errorf("unexpected error reconciling: %v", err)
			}

			err = verifyCreatesAndUpdates(clientset, test.expectCreate, test.expectUpdate)
			if err != nil {
				t.Errorf("unexpected error in side effects: %v", err)
			}

			if updatedKeys := fakeLeases.GetUpdatedKeys(); len(updatedKeys) != 1 || updatedKeys[0] != test.ip {
				t.Errorf("expected the master's IP to be refreshed, but the following IPs were refreshed instead: %v", updatedKeys)
			}
		})
	}
}

func TestLeaseRemoveEndpoints(t *testing.T) {
	stopTests := []struct {
		testName      string
		serviceName   string
		ip            string
		endpointPorts []corev1.EndpointPort
		endpointKeys  []string
		initialState  []runtime.Object
		expectUpdate  []runtime.Object
	}{
		{
			testName:      "successful stop reconciling",
			serviceName:   "foo",
			ip:            "1.2.3.4",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			endpointKeys:  []string{"1.2.3.4", "4.3.2.2", "4.3.2.3", "4.3.2.4"},
			initialState:  makeEndpointsArray("foo", []string{"1.2.3.4", "4.3.2.2", "4.3.2.3", "4.3.2.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
			expectUpdate:  makeEndpointsArray("foo", []string{"4.3.2.2", "4.3.2.3", "4.3.2.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "stop reconciling with ip not in endpoint ip list",
			serviceName:   "foo",
			ip:            "5.6.7.8",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			endpointKeys:  []string{"1.2.3.4", "4.3.2.2", "4.3.2.3", "4.3.2.4"},
			initialState:  makeEndpointsArray("foo", []string{"1.2.3.4", "4.3.2.2", "4.3.2.3", "4.3.2.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
		{
			testName:      "endpoint with no subset",
			serviceName:   "foo",
			ip:            "5.6.7.8",
			endpointPorts: []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}},
			endpointKeys:  []string{"1.2.3.4", "4.3.2.2", "4.3.2.3", "4.3.2.4"},
			initialState:  makeEndpointsArray("foo", nil, nil),
			expectUpdate:  makeEndpointsArray("foo", []string{"1.2.3.4", "4.3.2.2", "4.3.2.3", "4.3.2.4"}, []corev1.EndpointPort{{Name: "foo", Port: 8080, Protocol: "TCP"}}),
		},
	}
	for _, test := range stopTests {
		t.Run(test.testName, func(t *testing.T) {
			fakeLeases := newFakeLeases()
			fakeLeases.SetKeys(test.endpointKeys)
			clientset := fake.NewSimpleClientset(test.initialState...)
			epAdapter := NewEndpointsAdapter(clientset.CoreV1(), clientset.DiscoveryV1())
			r := NewLeaseEndpointReconciler(epAdapter, fakeLeases)
			err := r.RemoveEndpoints(test.serviceName, netutils.ParseIPSloppy(test.ip), test.endpointPorts)
			if err != nil {
				t.Errorf("unexpected error reconciling: %v", err)
			}

			err = verifyCreatesAndUpdates(clientset, nil, test.expectUpdate)
			if err != nil {
				t.Errorf("unexpected error in side effects: %v", err)
			}

			for _, key := range fakeLeases.GetUpdatedKeys() {
				if key == test.ip {
					t.Errorf("Found ip %s in leases but shouldn't be there", key)
				}
			}
		})
	}
}