/*
Copyright 2020 VMware, Inc.
SPDX-License-Identifier: Apache-2.0
*/

package logindiscovery

import (
	"context"
	"strings"
	"testing"
	"time"

	"github.com/sclevine/spec"
	"github.com/sclevine/spec/report"
	"github.com/stretchr/testify/require"
	corev1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime/schema"
	kubernetesfake "k8s.io/client-go/kubernetes/fake"
	coretesting "k8s.io/client-go/testing"

	"github.com/suzerain-io/controller-go"
	placeholderv1alpha1 "github.com/suzerain-io/placeholder-name-api/pkg/apis/placeholder/v1alpha1"
	placeholderfake "github.com/suzerain-io/placeholder-name-client-go/pkg/generated/clientset/versioned/fake"
)

func TestRun(t *testing.T) {
	spec.Run(t, "publisher", func(t *testing.T, when spec.G, it spec.S) {
		const installedInNamespace = "some-namespace"

		var r *require.Assertions

		var subject controller.Controller
		var kubeClient *kubernetesfake.Clientset
		var placeholderClient *placeholderfake.Clientset
		var timeoutContext context.Context
		var timeoutContextCancel context.CancelFunc
		var controllerContext *controller.Context

		var expectedLoginDiscoveryConfig = func(expectedNamespace, expectedServerURL, expectedCAData string) (schema.GroupVersionResource, *placeholderv1alpha1.LoginDiscoveryConfig) {
			expectedLoginDiscoveryConfigGVR := schema.GroupVersionResource{
				Group:    placeholderv1alpha1.GroupName,
				Version:  "v1alpha1",
				Resource: "logindiscoveryconfigs",
			}
			expectedLoginDiscoveryConfig := &placeholderv1alpha1.LoginDiscoveryConfig{
				ObjectMeta: metav1.ObjectMeta{
					Name:      "placeholder-name-config",
					Namespace: expectedNamespace,
				},
				Spec: placeholderv1alpha1.LoginDiscoveryConfigSpec{
					Server:                   expectedServerURL,
					CertificateAuthorityData: expectedCAData,
				},
			}
			return expectedLoginDiscoveryConfigGVR, expectedLoginDiscoveryConfig
		}

		it.Before(func() {
			r = require.New(t)
			kubeClient = kubernetesfake.NewSimpleClientset()
			placeholderClient = placeholderfake.NewSimpleClientset()
			timeoutContext, timeoutContextCancel = context.WithTimeout(context.Background(), time.Second*3)
			subject = NewPublisherController(installedInNamespace, kubeClient, placeholderClient)
			controllerContext = &controller.Context{
				Context: timeoutContext,
				Name:    subject.Name(),
				Key: controller.Key{
					Namespace: "kube-public",
					Name:      "cluster-info",
				},
			}
		})

		when("there is a cluster-info ConfigMap in the kube-public namespace", func() {
			const caData = "c29tZS1jZXJ0aWZpY2F0ZS1hdXRob3JpdHktZGF0YQo=" // "some-certificate-authority-data" base64 encoded
			const kubeServerURL = "https://some-server"
			var clusterInfoConfigMap *corev1.ConfigMap

			when("the ConfigMap has the expected `kubeconfig` top-level data key", func() {
				it.Before(func() {
					clusterInfoConfigMap = &corev1.ConfigMap{
						ObjectMeta: metav1.ObjectMeta{Name: "cluster-info", Namespace: "kube-public"},
						// Note that go fmt puts tabs in our file, which we must remove from our configmap yaml below.
						Data: map[string]string{
							"kubeconfig": strings.ReplaceAll(`
							kind: Config
							apiVersion: v1
							clusters:
							- name: ""
							  cluster:
							    certificate-authority-data: "`+caData+`"
							    server: "`+kubeServerURL+`"`, "\t", "  "),
							"uninteresting-key": "uninteresting-value",
						},
					}
					err := kubeClient.Tracker().Add(clusterInfoConfigMap)
					r.NoError(err)
				})

				when("the LoginDiscoveryConfig does not already exist", func() {
					it("creates a LoginDiscoveryConfig", func() {
						defer timeoutContextCancel()

						err := controller.TestSync(t, subject, *controllerContext)
						r.NoError(err)

						expectedLoginDiscoveryConfigGVR, expectedLoginDiscoveryConfig := expectedLoginDiscoveryConfig(installedInNamespace, kubeServerURL, caData)
						expectedActions := []coretesting.Action{
							coretesting.NewCreateAction(expectedLoginDiscoveryConfigGVR, installedInNamespace, expectedLoginDiscoveryConfig),
						}

						// Expect a LoginDiscoveryConfig to be created with the fields from the cluster-info ConfigMap
						actualCreatedObject := placeholderClient.Actions()[0].(coretesting.CreateActionImpl).Object
						r.Equal(expectedLoginDiscoveryConfig, actualCreatedObject)
						r.Equal(expectedActions, placeholderClient.Actions())
					})
				})

				when("the LoginDiscoveryConfig already exists", func() {
					when("the LoginDiscoveryConfig is already up to date according to the data in the ConfigMap", func() {
						it.Before(func() {
							// TODO add a fake LoginDiscoveryConfig to the placeholderClient whose data matches the ConfigMap's data
						})

						it.Pend("does not update the LoginDiscoveryConfig to avoid unnecessary etcd writes", func() {
							err := controller.TestSync(t, subject, *controllerContext)
							r.NoError(err)
							r.Empty(placeholderClient.Actions())
						})
					})

					when("the LoginDiscoveryConfig is stale compared to the data in the ConfigMap", func() {
						it.Before(func() {
							// TODO add a fake LoginDiscoveryConfig to the placeholderClient whose data does not match the ConfigMap's data
						})

						it.Pend("updates the existing LoginDiscoveryConfig", func() {
							// TODO
						})
					})
				})
			})

			when("the ConfigMap is missing the expected `kubeconfig` top-level data key", func() {
				it.Before(func() {
					clusterInfoConfigMap = &corev1.ConfigMap{
						ObjectMeta: metav1.ObjectMeta{Name: "cluster-info", Namespace: "kube-public"},
						Data: map[string]string{
							"these are not the droids you're looking for": "uninteresting-value",
						},
					}
					err := kubeClient.Tracker().Add(clusterInfoConfigMap)
					r.NoError(err)
				})

				it("keeps waiting for it to exist", func() {
					err := controller.TestSync(t, subject, *controllerContext)
					r.NoError(err)
					r.Empty(placeholderClient.Actions())
				})
			})
		})

		when("there is not a cluster-info ConfigMap in the kube-public namespace", func() {
			it.Before(func() {
				unrelatedConfigMap := &corev1.ConfigMap{
					ObjectMeta: metav1.ObjectMeta{
						Name:      "oops this is not the cluster-info ConfigMap",
						Namespace: "kube-public",
					},
				}
				err := kubeClient.Tracker().Add(unrelatedConfigMap)
				r.NoError(err)
			})

			it("keeps waiting for one", func() {
				err := controller.TestSync(t, subject, *controllerContext)
				r.NoError(err)
				r.Empty(placeholderClient.Actions())
			})
		})
	}, spec.Parallel(), spec.Report(report.Terminal{}))
}