/*
Copyright 2018 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 controller

import (
	"crypto/x509"
	"crypto/x509/pkix"
	"encoding/asn1"
	"k8s.io/apimachinery/pkg/util/intstr"
	"testing"

	extensions "k8s.io/api/extensions/v1beta1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/ingress-nginx/internal/ingress"
)

func TestMergeAlternativeBackends(t *testing.T) {
	testCases := map[string]struct {
		ingress                   *extensions.Ingress
		upstreams                 map[string]*ingress.Backend
		servers                   map[string]*ingress.Server
		expNumAlternativeBackends int
		expNumLocations           int
	}{
		"alternative backend has no server and embeds into matching real backend": {
			&extensions.Ingress{
				ObjectMeta: metav1.ObjectMeta{
					Namespace: "example",
				},
				Spec: extensions.IngressSpec{
					Rules: []extensions.IngressRule{
						{
							Host: "example.com",
							IngressRuleValue: extensions.IngressRuleValue{
								HTTP: &extensions.HTTPIngressRuleValue{
									Paths: []extensions.HTTPIngressPath{
										{
											Path: "/",
											Backend: extensions.IngressBackend{
												ServiceName: "http-svc-canary",
												ServicePort: intstr.IntOrString{
													Type:   intstr.Int,
													IntVal: 80,
												},
											},
										},
									},
								},
							},
						},
					},
				},
			},
			map[string]*ingress.Backend{
				"example-http-svc-80": {
					Name:     "example-http-svc-80",
					NoServer: false,
				},
				"example-http-svc-canary-80": {
					Name:     "example-http-svc-canary-80",
					NoServer: true,
					TrafficShapingPolicy: ingress.TrafficShapingPolicy{
						Weight: 20,
					},
				},
			},
			map[string]*ingress.Server{
				"example.com": {
					Hostname: "example.com",
					Locations: []*ingress.Location{
						{
							Path:    "/",
							Backend: "example-http-svc-80",
						},
					},
				},
			},
			1,
			1,
		},
		"merging a alternative backend matches with the correct host": {
			&extensions.Ingress{
				ObjectMeta: metav1.ObjectMeta{
					Namespace: "example",
				},
				Spec: extensions.IngressSpec{
					Rules: []extensions.IngressRule{
						{
							Host: "foo.bar",
							IngressRuleValue: extensions.IngressRuleValue{
								HTTP: &extensions.HTTPIngressRuleValue{
									Paths: []extensions.HTTPIngressPath{
										{
											Path: "/",
											Backend: extensions.IngressBackend{
												ServiceName: "foo-http-svc-canary",
												ServicePort: intstr.IntOrString{
													Type:   intstr.Int,
													IntVal: 80,
												},
											},
										},
									},
								},
							},
						},
						{
							Host: "example.com",
							IngressRuleValue: extensions.IngressRuleValue{
								HTTP: &extensions.HTTPIngressRuleValue{
									Paths: []extensions.HTTPIngressPath{
										{
											Path: "/",
											Backend: extensions.IngressBackend{
												ServiceName: "http-svc-canary",
												ServicePort: intstr.IntOrString{
													Type:   intstr.Int,
													IntVal: 80,
												},
											},
										},
									},
								},
							},
						},
					},
				},
			},
			map[string]*ingress.Backend{
				"example-foo-http-svc-80": {
					Name:     "example-foo-http-svc-80",
					NoServer: false,
				},
				"example-foo-http-svc-canary-80": {
					Name:     "example-foo-http-svc-canary-80",
					NoServer: true,
					TrafficShapingPolicy: ingress.TrafficShapingPolicy{
						Weight: 20,
					},
				},
				"example-http-svc-80": {
					Name:     "example-http-svc-80",
					NoServer: false,
				},
				"example-http-svc-canary-80": {
					Name:     "example-http-svc-canary-80",
					NoServer: true,
					TrafficShapingPolicy: ingress.TrafficShapingPolicy{
						Weight: 20,
					},
				},
			},
			map[string]*ingress.Server{
				"foo.bar": {
					Hostname: "foo.bar",
					Locations: []*ingress.Location{
						{
							Path:    "/",
							Backend: "example-foo-http-svc-80",
						},
					},
				},
				"example.com": {
					Hostname: "example.com",
					Locations: []*ingress.Location{
						{
							Path:    "/",
							Backend: "example-http-svc-80",
						},
					},
				},
			},
			1,
			1,
		},
	}

	for title, tc := range testCases {
		t.Run(title, func(t *testing.T) {
			mergeAlternativeBackends(tc.ingress, tc.upstreams, tc.servers)

			numAlternativeBackends := len(tc.upstreams["example-http-svc-80"].AlternativeBackends)
			if numAlternativeBackends != tc.expNumAlternativeBackends {
				t.Errorf("expected %d alternative backends (got %d)", tc.expNumAlternativeBackends, numAlternativeBackends)
			}

			numLocations := len(tc.servers["example.com"].Locations)
			if numLocations != tc.expNumLocations {
				t.Errorf("expected %d locations (got %d)", tc.expNumLocations, numLocations)
			}
		})
	}
}

func TestExtractTLSSecretName(t *testing.T) {
	testCases := map[string]struct {
		host    string
		ingress *extensions.Ingress
		fn      func(string) (*ingress.SSLCert, error)
		expName string
	}{
		"nil ingress": {
			"foo.bar",
			nil,
			func(string) (*ingress.SSLCert, error) {
				return nil, nil
			},
			"",
		},
		"empty ingress": {
			"foo.bar",
			&extensions.Ingress{},
			func(string) (*ingress.SSLCert, error) {
				return nil, nil
			},
			"",
		},
		"ingress tls, nil secret": {
			"foo.bar",
			&extensions.Ingress{
				ObjectMeta: metav1.ObjectMeta{
					Name: "test",
				},
				Spec: extensions.IngressSpec{
					TLS: []extensions.IngressTLS{
						{SecretName: "demo"},
					},
					Rules: []extensions.IngressRule{
						{
							Host: "foo.bar",
						},
					},
				},
			},
			func(string) (*ingress.SSLCert, error) {
				return nil, nil
			},
			"",
		},
		"ingress tls, no host, matching cert cn": {
			"foo.bar",
			&extensions.Ingress{
				ObjectMeta: metav1.ObjectMeta{
					Name: "test",
				},
				Spec: extensions.IngressSpec{
					TLS: []extensions.IngressTLS{
						{SecretName: "demo"},
					},
					Rules: []extensions.IngressRule{
						{
							Host: "foo.bar",
						},
					},
				},
			},
			func(string) (*ingress.SSLCert, error) {
				return &ingress.SSLCert{
					Certificate: fakeX509Cert([]string{"foo.bar", "example.com"}),
				}, nil
			},
			"demo",
		},
		"ingress tls, no host, wildcard cert with matching cn": {
			"foo.bar",
			&extensions.Ingress{
				ObjectMeta: metav1.ObjectMeta{
					Name: "test",
				},
				Spec: extensions.IngressSpec{
					TLS: []extensions.IngressTLS{
						{
							SecretName: "demo",
						},
					},
					Rules: []extensions.IngressRule{
						{
							Host: "test.foo.bar",
						},
					},
				},
			},
			func(string) (*ingress.SSLCert, error) {
				return &ingress.SSLCert{
					Certificate: fakeX509Cert([]string{"*.foo.bar", "foo.bar"}),
				}, nil
			},
			"demo",
		},
		"ingress tls, hosts, matching cert cn": {
			"foo.bar",
			&extensions.Ingress{
				ObjectMeta: metav1.ObjectMeta{
					Name: "test",
				},
				Spec: extensions.IngressSpec{
					TLS: []extensions.IngressTLS{
						{
							Hosts:      []string{"foo.bar", "example.com"},
							SecretName: "demo",
						},
					},
					Rules: []extensions.IngressRule{
						{
							Host: "foo.bar",
						},
					},
				},
			},
			func(string) (*ingress.SSLCert, error) {
				return nil, nil
			},
			"demo",
		},
	}

	for title, tc := range testCases {
		t.Run(title, func(t *testing.T) {
			name := extractTLSSecretName(tc.host, tc.ingress, tc.fn)
			if name != tc.expName {
				t.Errorf("Expected Secret name %q (got %q)", tc.expName, name)
			}
		})
	}
}

var oidExtensionSubjectAltName = asn1.ObjectIdentifier{2, 5, 29, 17}

func fakeX509Cert(dnsNames []string) *x509.Certificate {
	return &x509.Certificate{
		DNSNames: dnsNames,
		Extensions: []pkix.Extension{
			{Id: oidExtensionSubjectAltName},
		},
	}
}