/*
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 source

import (
	"testing"

	istionetworking "istio.io/api/networking/v1alpha3"
	istiomodel "istio.io/istio/pilot/pkg/model"

	"github.com/kubernetes-incubator/external-dns/endpoint"

	"strconv"
	"sync"

	"github.com/pkg/errors"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"github.com/stretchr/testify/suite"
	"k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/client-go/kubernetes/fake"
)

// This is a compile-time validation that gatewaySource is a Source.
var _ Source = &gatewaySource{}

var gatewayType = istiomodel.Gateway.Type

type GatewaySuite struct {
	suite.Suite
	source  Source
	ingress *v1.Service
	config  istiomodel.Config
}

func (suite *GatewaySuite) SetupTest() {
	fakeKubernetesClient := fake.NewSimpleClientset()
	fakeIstioClient := NewFakeConfigStore()
	var err error

	suite.ingress = (fakeIngressGateway{
		ips:       []string{"8.8.8.8"},
		hostnames: []string{"v1"},
	}).Service()
	_, err = fakeKubernetesClient.CoreV1().Services(suite.ingress.Namespace).Create(suite.ingress)
	suite.NoError(err, "should succeed")

	suite.source, err = NewIstioGatewaySource(
		fakeKubernetesClient,
		fakeIstioClient,
		"istio-system/istio-ingressgateway",
		"default",
		"",
		"{{.Name}}",
		false,
		false,
	)
	suite.NoError(err, "should initialize gateway source")

	suite.config = (fakeGatewayConfig{
		name:      "foo-gateway-with-targets",
		namespace: "default",
		dnsnames:  [][]string{{"foo"}},
	}).Config()
	_, err = fakeIstioClient.Create(suite.config)
	suite.NoError(err, "should succeed")
}

func (suite *GatewaySuite) TestResourceLabelIsSet() {
	endpoints, _ := suite.source.Endpoints()
	for _, ep := range endpoints {
		suite.Equal("gateway/default/foo-gateway-with-targets", ep.Labels[endpoint.ResourceLabelKey], "should set correct resource label")
	}
}

func TestGateway(t *testing.T) {
	suite.Run(t, new(GatewaySuite))
	t.Run("endpointsFromGatewayConfig", testEndpointsFromGatewayConfig)
	t.Run("Endpoints", testGatewayEndpoints)
}

func TestNewIstioGatewaySource(t *testing.T) {
	for _, ti := range []struct {
		title                    string
		annotationFilter         string
		fqdnTemplate             string
		combineFQDNAndAnnotation bool
		expectError              bool
	}{
		{
			title:        "invalid template",
			expectError:  true,
			fqdnTemplate: "{{.Name",
		},
		{
			title:       "valid empty template",
			expectError: false,
		},
		{
			title:        "valid template",
			expectError:  false,
			fqdnTemplate: "{{.Name}}-{{.Namespace}}.ext-dns.test.com",
		},
		{
			title:        "valid template",
			expectError:  false,
			fqdnTemplate: "{{.Name}}-{{.Namespace}}.ext-dns.test.com, {{.Name}}-{{.Namespace}}.ext-dna.test.com",
		},
		{
			title:                    "valid template",
			expectError:              false,
			fqdnTemplate:             "{{.Name}}-{{.Namespace}}.ext-dns.test.com, {{.Name}}-{{.Namespace}}.ext-dna.test.com",
			combineFQDNAndAnnotation: true,
		},
		{
			title:            "non-empty annotation filter label",
			expectError:      false,
			annotationFilter: "kubernetes.io/gateway.class=nginx",
		},
	} {
		t.Run(ti.title, func(t *testing.T) {
			_, err := NewIstioGatewaySource(
				fake.NewSimpleClientset(),
				NewFakeConfigStore(),
				"istio-system/istio-ingressgateway",
				"",
				ti.annotationFilter,
				ti.fqdnTemplate,
				ti.combineFQDNAndAnnotation,
				false,
			)
			if ti.expectError {
				assert.Error(t, err)
			} else {
				assert.NoError(t, err)
			}
		})
	}
}

func testEndpointsFromGatewayConfig(t *testing.T) {
	for _, ti := range []struct {
		title    string
		ingress  fakeIngressGateway
		config   fakeGatewayConfig
		expected []*endpoint.Endpoint
	}{
		{
			title: "one rule.host one lb.hostname",
			ingress: fakeIngressGateway{
				hostnames: []string{"lb.com"}, // Kubernetes omits the trailing dot
			},
			config: fakeGatewayConfig{
				dnsnames: [][]string{
					{"foo.bar"}, // Kubernetes requires removal of trailing dot
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName: "foo.bar",
					Targets: endpoint.Targets{"lb.com"},
				},
			},
		},
		{
			title: "one rule.host one lb.IP",
			ingress: fakeIngressGateway{
				ips: []string{"8.8.8.8"},
			},
			config: fakeGatewayConfig{
				dnsnames: [][]string{
					{"foo.bar"},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName: "foo.bar",
					Targets: endpoint.Targets{"8.8.8.8"},
				},
			},
		},
		{
			title: "one rule.host two lb.IP and two lb.Hostname",
			ingress: fakeIngressGateway{
				ips:       []string{"8.8.8.8", "127.0.0.1"},
				hostnames: []string{"elb.com", "alb.com"},
			},
			config: fakeGatewayConfig{
				dnsnames: [][]string{
					{"foo.bar"},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName: "foo.bar",
					Targets: endpoint.Targets{"8.8.8.8", "127.0.0.1"},
				},
				{
					DNSName: "foo.bar",
					Targets: endpoint.Targets{"elb.com", "alb.com"},
				},
			},
		},
		{
			title: "no rule.host",
			ingress: fakeIngressGateway{
				ips:       []string{"8.8.8.8", "127.0.0.1"},
				hostnames: []string{"elb.com", "alb.com"},
			},
			config: fakeGatewayConfig{
				dnsnames: [][]string{},
			},
			expected: []*endpoint.Endpoint{},
		},
		{
			title: "one empty rule.host",
			ingress: fakeIngressGateway{
				ips:       []string{"8.8.8.8", "127.0.0.1"},
				hostnames: []string{"elb.com", "alb.com"},
			},
			config: fakeGatewayConfig{
				dnsnames: [][]string{
					{""},
				},
			},
			expected: []*endpoint.Endpoint{},
		},
		{
			title:   "no targets",
			ingress: fakeIngressGateway{},
			config: fakeGatewayConfig{
				dnsnames: [][]string{
					{""},
				},
			},
			expected: []*endpoint.Endpoint{},
		},
	} {
		t.Run(ti.title, func(t *testing.T) {
			if source, err := newTestGatewaySource(ti.ingress.Service()); err != nil {
				require.NoError(t, err)
			} else if endpoints, err := source.endpointsFromGatewayConfig(ti.config.Config()); err != nil {
				require.NoError(t, err)
			} else {
				validateEndpoints(t, endpoints, ti.expected)
			}
		})
	}
}

func testGatewayEndpoints(t *testing.T) {
	namespace := "testing"
	for _, ti := range []struct {
		title                    string
		targetNamespace          string
		annotationFilter         string
		ingressGateway           fakeIngressGateway
		configItems              []fakeGatewayConfig
		expected                 []*endpoint.Endpoint
		expectError              bool
		fqdnTemplate             string
		combineFQDNAndAnnotation bool
		ignoreHostnameAnnotation bool
	}{
		{
			title:           "no gateway",
			targetNamespace: "",
		},
		{
			title:           "two simple gateways",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips:       []string{"8.8.8.8"},
				hostnames: []string{"lb.com"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					dnsnames:  [][]string{{"example.org"}},
				},
				{
					name:      "fake2",
					namespace: namespace,
					dnsnames:  [][]string{{"new.org"}},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName: "example.org",
					Targets: endpoint.Targets{"8.8.8.8"},
				},
				{
					DNSName: "example.org",
					Targets: endpoint.Targets{"lb.com"},
				},
				{
					DNSName: "new.org",
					Targets: endpoint.Targets{"8.8.8.8"},
				},
				{
					DNSName: "new.org",
					Targets: endpoint.Targets{"lb.com"},
				},
			},
		},
		{
			title:           "two simple gateways on different namespaces",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips:       []string{"8.8.8.8"},
				hostnames: []string{"lb.com"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: "testing1",
					dnsnames:  [][]string{{"example.org"}},
				},
				{
					name:      "fake2",
					namespace: "testing2",
					dnsnames:  [][]string{{"new.org"}},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName: "example.org",
					Targets: endpoint.Targets{"8.8.8.8"},
				},
				{
					DNSName: "example.org",
					Targets: endpoint.Targets{"lb.com"},
				},
				{
					DNSName: "new.org",
					Targets: endpoint.Targets{"8.8.8.8"},
				},
				{
					DNSName: "new.org",
					Targets: endpoint.Targets{"lb.com"},
				},
			},
		},
		{
			title:           "two simple gateways on different namespaces with target namespace",
			targetNamespace: "testing1",
			ingressGateway: fakeIngressGateway{
				ips:       []string{"8.8.8.8"},
				hostnames: []string{"lb.com"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: "testing1",
					dnsnames:  [][]string{{"example.org"}},
				},
				{
					name:      "fake2",
					namespace: "testing2",
					dnsnames:  [][]string{{"new.org"}},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName: "example.org",
					Targets: endpoint.Targets{"8.8.8.8"},
				},
				{
					DNSName: "example.org",
					Targets: endpoint.Targets{"lb.com"},
				},
			},
		},
		{
			title:            "valid matching annotation filter expression",
			targetNamespace:  "",
			annotationFilter: "kubernetes.io/gateway.class in (alb, nginx)",
			ingressGateway: fakeIngressGateway{
				ips: []string{"8.8.8.8"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						"kubernetes.io/gateway.class": "nginx",
					},
					dnsnames: [][]string{{"example.org"}},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName: "example.org",
					Targets: endpoint.Targets{"8.8.8.8"},
				},
			},
		},
		{
			title:            "valid non-matching annotation filter expression",
			targetNamespace:  "",
			annotationFilter: "kubernetes.io/gateway.class in (alb, nginx)",
			ingressGateway: fakeIngressGateway{
				ips: []string{"8.8.8.8"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						"kubernetes.io/gateway.class": "tectonic",
					},
					dnsnames: [][]string{{"example.org"}},
				},
			},
			expected: []*endpoint.Endpoint{},
		},
		{
			title:            "invalid annotation filter expression",
			targetNamespace:  "",
			annotationFilter: "kubernetes.io/gateway.name in (a b)",
			ingressGateway: fakeIngressGateway{
				ips: []string{"8.8.8.8"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						"kubernetes.io/gateway.class": "alb",
					},
					dnsnames: [][]string{{"example.org"}},
				},
			},
			expected:    []*endpoint.Endpoint{},
			expectError: true,
		},
		{
			title:            "valid matching annotation filter label",
			targetNamespace:  "",
			annotationFilter: "kubernetes.io/gateway.class=nginx",
			ingressGateway: fakeIngressGateway{
				ips: []string{"8.8.8.8"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						"kubernetes.io/gateway.class": "nginx",
					},
					dnsnames: [][]string{{"example.org"}},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName: "example.org",
					Targets: endpoint.Targets{"8.8.8.8"},
				},
			},
		},
		{
			title:            "valid non-matching annotation filter label",
			targetNamespace:  "",
			annotationFilter: "kubernetes.io/gateway.class=nginx",
			ingressGateway: fakeIngressGateway{
				ips: []string{"8.8.8.8"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						"kubernetes.io/gateway.class": "alb",
					},
					dnsnames: [][]string{{"example.org"}},
				},
			},
			expected: []*endpoint.Endpoint{},
		},
		{
			title:           "our controller type is dns-controller",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips: []string{"8.8.8.8"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						controllerAnnotationKey: controllerAnnotationValue,
					},
					dnsnames: [][]string{{"example.org"}},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName: "example.org",
					Targets: endpoint.Targets{"8.8.8.8"},
				},
			},
		},
		{
			title:           "different controller types are ignored",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips: []string{"8.8.8.8"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						controllerAnnotationKey: "some-other-tool",
					},
					dnsnames: [][]string{{"example.org"}},
				},
			},
			expected: []*endpoint.Endpoint{},
		},
		{
			title:           "template for gateway if host is missing",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips:       []string{"8.8.8.8"},
				hostnames: []string{"elb.com"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						controllerAnnotationKey: controllerAnnotationValue,
					},
					dnsnames: [][]string{},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName: "fake1.ext-dns.test.com",
					Targets: endpoint.Targets{"8.8.8.8"},
				},
				{
					DNSName: "fake1.ext-dns.test.com",
					Targets: endpoint.Targets{"elb.com"},
				},
			},
			fqdnTemplate: "{{.Name}}.ext-dns.test.com",
		},
		{
			title:           "another controller annotation skipped even with template",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips: []string{"8.8.8.8"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						controllerAnnotationKey: "other-controller",
					},
					dnsnames: [][]string{},
				},
			},
			expected:     []*endpoint.Endpoint{},
			fqdnTemplate: "{{.Name}}.ext-dns.test.com",
		},
		{
			title:           "multiple FQDN template hostnames",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips: []string{"8.8.8.8"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:        "fake1",
					namespace:   namespace,
					annotations: map[string]string{},
					dnsnames:    [][]string{},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName:    "fake1.ext-dns.test.com",
					Targets:    endpoint.Targets{"8.8.8.8"},
					RecordType: endpoint.RecordTypeA,
				},
				{
					DNSName:    "fake1.ext-dna.test.com",
					Targets:    endpoint.Targets{"8.8.8.8"},
					RecordType: endpoint.RecordTypeA,
				},
			},
			fqdnTemplate: "{{.Name}}.ext-dns.test.com, {{.Name}}.ext-dna.test.com",
		},
		{
			title:           "multiple FQDN template hostnames",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips: []string{"8.8.8.8"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:        "fake1",
					namespace:   namespace,
					annotations: map[string]string{},
					dnsnames:    [][]string{},
				},
				{
					name:      "fake2",
					namespace: namespace,
					annotations: map[string]string{
						targetAnnotationKey: "gateway-target.com",
					},
					dnsnames: [][]string{{"example.org"}},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName:    "fake1.ext-dns.test.com",
					Targets:    endpoint.Targets{"8.8.8.8"},
					RecordType: endpoint.RecordTypeA,
				},
				{
					DNSName:    "fake1.ext-dna.test.com",
					Targets:    endpoint.Targets{"8.8.8.8"},
					RecordType: endpoint.RecordTypeA,
				},
				{
					DNSName:    "example.org",
					Targets:    endpoint.Targets{"gateway-target.com"},
					RecordType: endpoint.RecordTypeCNAME,
				},
				{
					DNSName:    "fake2.ext-dns.test.com",
					Targets:    endpoint.Targets{"gateway-target.com"},
					RecordType: endpoint.RecordTypeCNAME,
				},
				{
					DNSName:    "fake2.ext-dna.test.com",
					Targets:    endpoint.Targets{"gateway-target.com"},
					RecordType: endpoint.RecordTypeCNAME,
				},
			},
			fqdnTemplate:             "{{.Name}}.ext-dns.test.com, {{.Name}}.ext-dna.test.com",
			combineFQDNAndAnnotation: true,
		},
		{
			title:           "gateway rules with annotation",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips: []string{"8.8.8.8"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						targetAnnotationKey: "gateway-target.com",
					},
					dnsnames: [][]string{{"example.org"}},
				},
				{
					name:      "fake2",
					namespace: namespace,
					annotations: map[string]string{
						targetAnnotationKey: "gateway-target.com",
					},
					dnsnames: [][]string{{"example2.org"}},
				},
				{
					name:      "fake3",
					namespace: namespace,
					annotations: map[string]string{
						targetAnnotationKey: "1.2.3.4",
					},
					dnsnames: [][]string{{"example3.org"}},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName:    "example.org",
					Targets:    endpoint.Targets{"gateway-target.com"},
					RecordType: endpoint.RecordTypeCNAME,
				},
				{
					DNSName:    "example2.org",
					Targets:    endpoint.Targets{"gateway-target.com"},
					RecordType: endpoint.RecordTypeCNAME,
				},
				{
					DNSName:    "example3.org",
					Targets:    endpoint.Targets{"1.2.3.4"},
					RecordType: endpoint.RecordTypeA,
				},
			},
		},
		{
			title:           "gateway rules with hostname annotation",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips: []string{"1.2.3.4"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						hostnameAnnotationKey: "dns-through-hostname.com",
					},
					dnsnames: [][]string{{"example.org"}},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName:    "example.org",
					Targets:    endpoint.Targets{"1.2.3.4"},
					RecordType: endpoint.RecordTypeA,
				},
				{
					DNSName:    "dns-through-hostname.com",
					Targets:    endpoint.Targets{"1.2.3.4"},
					RecordType: endpoint.RecordTypeA,
				},
			},
		},
		{
			title:           "gateway rules with hostname annotation having multiple hostnames",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips: []string{"1.2.3.4"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						hostnameAnnotationKey: "dns-through-hostname.com, another-dns-through-hostname.com",
					},
					dnsnames: [][]string{{"example.org"}},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName:    "example.org",
					Targets:    endpoint.Targets{"1.2.3.4"},
					RecordType: endpoint.RecordTypeA,
				},
				{
					DNSName:    "dns-through-hostname.com",
					Targets:    endpoint.Targets{"1.2.3.4"},
					RecordType: endpoint.RecordTypeA,
				},
				{
					DNSName:    "another-dns-through-hostname.com",
					Targets:    endpoint.Targets{"1.2.3.4"},
					RecordType: endpoint.RecordTypeA,
				},
			},
		},
		{
			title:           "gateway rules with hostname and target annotation",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips: []string{},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						hostnameAnnotationKey: "dns-through-hostname.com",
						targetAnnotationKey:   "gateway-target.com",
					},
					dnsnames: [][]string{{"example.org"}},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName:    "example.org",
					Targets:    endpoint.Targets{"gateway-target.com"},
					RecordType: endpoint.RecordTypeCNAME,
				},
				{
					DNSName:    "dns-through-hostname.com",
					Targets:    endpoint.Targets{"gateway-target.com"},
					RecordType: endpoint.RecordTypeCNAME,
				},
			},
		},
		{
			title:           "gateway rules with annotation and custom TTL",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips: []string{"8.8.8.8"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						targetAnnotationKey: "gateway-target.com",
						ttlAnnotationKey:    "6",
					},
					dnsnames: [][]string{{"example.org"}},
				},
				{
					name:      "fake2",
					namespace: namespace,
					annotations: map[string]string{
						targetAnnotationKey: "gateway-target.com",
						ttlAnnotationKey:    "1",
					},
					dnsnames: [][]string{{"example2.org"}},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName:   "example.org",
					Targets:   endpoint.Targets{"gateway-target.com"},
					RecordTTL: endpoint.TTL(6),
				},
				{
					DNSName:   "example2.org",
					Targets:   endpoint.Targets{"gateway-target.com"},
					RecordTTL: endpoint.TTL(1),
				},
			},
		},
		{
			title:           "template for gateway with annotation",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips:       []string{},
				hostnames: []string{},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						targetAnnotationKey: "gateway-target.com",
					},
					dnsnames: [][]string{},
				},
				{
					name:      "fake2",
					namespace: namespace,
					annotations: map[string]string{
						targetAnnotationKey: "gateway-target.com",
					},
					dnsnames: [][]string{},
				},
				{
					name:      "fake3",
					namespace: namespace,
					annotations: map[string]string{
						targetAnnotationKey: "1.2.3.4",
					},
					dnsnames: [][]string{},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName:    "fake1.ext-dns.test.com",
					Targets:    endpoint.Targets{"gateway-target.com"},
					RecordType: endpoint.RecordTypeCNAME,
				},
				{
					DNSName:    "fake2.ext-dns.test.com",
					Targets:    endpoint.Targets{"gateway-target.com"},
					RecordType: endpoint.RecordTypeCNAME,
				},
				{
					DNSName:    "fake3.ext-dns.test.com",
					Targets:    endpoint.Targets{"1.2.3.4"},
					RecordType: endpoint.RecordTypeA,
				},
			},
			fqdnTemplate: "{{.Name}}.ext-dns.test.com",
		},
		{
			title:           "Ingress with empty annotation",
			targetNamespace: "",
			ingressGateway: fakeIngressGateway{
				ips:       []string{},
				hostnames: []string{},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						targetAnnotationKey: "",
					},
					dnsnames: [][]string{},
				},
			},
			expected:     []*endpoint.Endpoint{},
			fqdnTemplate: "{{.Name}}.ext-dns.test.com",
		},
		{
			title:                    "ignore hostname annotations",
			ignoreHostnameAnnotation: true,
			targetNamespace:          "",
			ingressGateway: fakeIngressGateway{
				ips:       []string{"8.8.8.8"},
				hostnames: []string{"lb.com"},
			},
			configItems: []fakeGatewayConfig{
				{
					name:      "fake1",
					namespace: namespace,
					annotations: map[string]string{
						hostnameAnnotationKey: "ignore.me",
					},
					dnsnames: [][]string{{"example.org"}},
				},
				{
					name:      "fake2",
					namespace: namespace,
					annotations: map[string]string{
						hostnameAnnotationKey: "ignore.me.too",
					},
					dnsnames: [][]string{{"new.org"}},
				},
			},
			expected: []*endpoint.Endpoint{
				{
					DNSName: "example.org",
					Targets: endpoint.Targets{"8.8.8.8"},
				},
				{
					DNSName: "example.org",
					Targets: endpoint.Targets{"lb.com"},
				},
				{
					DNSName: "new.org",
					Targets: endpoint.Targets{"8.8.8.8"},
				},
				{
					DNSName: "new.org",
					Targets: endpoint.Targets{"lb.com"},
				},
			},
		},
	} {
		t.Run(ti.title, func(t *testing.T) {
			configs := make([]istiomodel.Config, 0)
			for _, item := range ti.configItems {
				configs = append(configs, item.Config())
			}

			fakeKubernetesClient := fake.NewSimpleClientset()
			ingressGatewayService := ti.ingressGateway.Service()
			if _, err := fakeKubernetesClient.CoreV1().Services(ingressGatewayService.Namespace).Create(ingressGatewayService); err != nil {
				require.NoError(t, err)
			}
			fakeIstioClient := NewFakeConfigStore()
			for _, config := range configs {
				_, err := fakeIstioClient.Create(config)
				require.NoError(t, err)
			}

			gatewaySource, err := NewIstioGatewaySource(
				fakeKubernetesClient,
				fakeIstioClient,
				ingressGatewayService.Namespace+"/"+ingressGatewayService.Name,
				ti.targetNamespace,
				ti.annotationFilter,
				ti.fqdnTemplate,
				ti.combineFQDNAndAnnotation,
				ti.ignoreHostnameAnnotation,
			)
			require.NoError(t, err)

			res, err := gatewaySource.Endpoints()
			if ti.expectError {
				assert.Error(t, err)
			} else {
				assert.NoError(t, err)
			}

			validateEndpoints(t, res, ti.expected)
		})
	}
}

// gateway specific helper functions
func newTestGatewaySource(ingress *v1.Service) (*gatewaySource, error) {
	fakeKubernetesClient := fake.NewSimpleClientset()
	fakeIstioClient := NewFakeConfigStore()

	_, err := fakeKubernetesClient.CoreV1().Services(ingress.Namespace).Create(ingress)
	if err != nil {
		return nil, err
	}

	src, err := NewIstioGatewaySource(
		fakeKubernetesClient,
		fakeIstioClient,
		"istio-system/istio-ingressgateway",
		"default",
		"",
		"{{.Name}}",
		false,
		false,
	)
	if err != nil {
		return nil, err
	}

	gwsrc, ok := src.(*gatewaySource)
	if !ok {
		return nil, errors.New("underlying source type was not gateway")
	}

	return gwsrc, nil
}

type fakeIngressGateway struct {
	ips       []string
	hostnames []string
}

func (ig fakeIngressGateway) Service() *v1.Service {
	svc := &v1.Service{
		ObjectMeta: metav1.ObjectMeta{
			Namespace: "istio-system",
			Name:      "istio-ingressgateway",
		},
		Status: v1.ServiceStatus{
			LoadBalancer: v1.LoadBalancerStatus{
				Ingress: []v1.LoadBalancerIngress{},
			},
		},
	}

	for _, ip := range ig.ips {
		svc.Status.LoadBalancer.Ingress = append(svc.Status.LoadBalancer.Ingress, v1.LoadBalancerIngress{
			IP: ip,
		})
	}
	for _, hostname := range ig.hostnames {
		svc.Status.LoadBalancer.Ingress = append(svc.Status.LoadBalancer.Ingress, v1.LoadBalancerIngress{
			Hostname: hostname,
		})
	}

	return svc
}

type fakeGatewayConfig struct {
	namespace   string
	name        string
	annotations map[string]string
	dnsnames    [][]string
}

func (c fakeGatewayConfig) Config() istiomodel.Config {
	gw := &istionetworking.Gateway{
		Servers: []*istionetworking.Server{},
	}

	for _, dnsnames := range c.dnsnames {
		gw.Servers = append(gw.Servers, &istionetworking.Server{
			Hosts: dnsnames,
		})
	}

	config := istiomodel.Config{
		ConfigMeta: istiomodel.ConfigMeta{
			Namespace:   c.namespace,
			Name:        c.name,
			Type:        gatewayType,
			Annotations: c.annotations,
		},
		Spec: gw,
	}

	return config
}

type fakeConfigStore struct {
	descriptor istiomodel.ConfigDescriptor
	configs    []*istiomodel.Config
	sync.RWMutex
}

func NewFakeConfigStore() istiomodel.ConfigStore {
	return &fakeConfigStore{
		descriptor: istiomodel.ConfigDescriptor{
			istiomodel.Gateway,
		},
		configs: make([]*istiomodel.Config, 0),
	}
}

func (f *fakeConfigStore) ConfigDescriptor() istiomodel.ConfigDescriptor {
	return f.descriptor
}

func (f *fakeConfigStore) Get(typ, name, namespace string) (config *istiomodel.Config, exists bool) {
	f.RLock()
	defer f.RUnlock()

	if cfg, _ := f.get(typ, name, namespace); cfg != nil {
		config = cfg
		exists = true
	}

	return
}

func (f *fakeConfigStore) get(typ, name, namespace string) (*istiomodel.Config, int) {
	for idx, cfg := range f.configs {
		if cfg.Type == typ && cfg.Name == name && cfg.Namespace == namespace {
			return cfg, idx
		}
	}

	return nil, -1
}

func (f *fakeConfigStore) List(typ, namespace string) (configs []istiomodel.Config, err error) {
	f.RLock()
	defer f.RUnlock()

	if namespace == "" {
		for _, cfg := range f.configs {
			configs = append(configs, *cfg)
		}
	} else {
		for _, cfg := range f.configs {
			if cfg.Type == typ && cfg.Namespace == namespace {
				configs = append(configs, *cfg)
			}
		}
	}

	return
}

func (f *fakeConfigStore) Create(config istiomodel.Config) (revision string, err error) {
	f.Lock()
	defer f.Unlock()

	if cfg, _ := f.get(config.Type, config.Name, config.Namespace); cfg != nil {
		err = errors.New("config already exists")
	} else {
		revision = "0"
		cfg := &config
		cfg.ResourceVersion = revision
		f.configs = append(f.configs, cfg)
	}

	return
}

func (f *fakeConfigStore) Update(config istiomodel.Config) (newRevision string, err error) {
	f.Lock()
	defer f.Unlock()

	if oldCfg, idx := f.get(config.Type, config.Name, config.Namespace); oldCfg == nil {
		err = errors.New("config does not exist")
	} else if oldRevision, e := strconv.Atoi(oldCfg.ResourceVersion); e != nil {
		err = e
	} else {
		newRevision = strconv.Itoa(oldRevision + 1)
		cfg := &config
		cfg.ResourceVersion = newRevision
		f.configs[idx] = cfg
	}

	return
}

func (f *fakeConfigStore) Delete(typ, name, namespace string) error {
	f.Lock()
	defer f.Unlock()

	_, idx := f.get(typ, name, namespace)
	if idx < 0 {
		return errors.New("config does not exist")
	}

	copy(f.configs[idx:], f.configs[idx+1:])
	f.configs[len(f.configs)-1] = nil
	f.configs = f.configs[:len(f.configs)-1]

	return nil
}