/*
Copyright 2020 the Velero contributors.

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 (
	"context"
	"time"

	. "github.com/onsi/ginkgo"
	. "github.com/onsi/ginkgo/extensions/table"
	. "github.com/onsi/gomega"
	apierrors "k8s.io/apimachinery/pkg/api/errors"
	"k8s.io/apimachinery/pkg/types"
	"k8s.io/apimachinery/pkg/util/clock"
	"k8s.io/client-go/kubernetes/scheme"

	ctrl "sigs.k8s.io/controller-runtime"
	kbclient "sigs.k8s.io/controller-runtime/pkg/client"
	"sigs.k8s.io/controller-runtime/pkg/client/fake"

	velerov1api "github.com/vmware-tanzu/velero/pkg/apis/velero/v1"
	"github.com/vmware-tanzu/velero/pkg/builder"
	"github.com/vmware-tanzu/velero/pkg/buildinfo"
	"github.com/vmware-tanzu/velero/pkg/plugin/framework"
	velerotest "github.com/vmware-tanzu/velero/pkg/test"
)

func statusRequestBuilder(resourceVersion string) *builder.ServerStatusRequestBuilder {
	return builder.ForServerStatusRequest(velerov1api.DefaultNamespace, "sr-1", resourceVersion)
}

var _ = Describe("Server Status Request Reconciler", func() {
	type request struct {
		req             *velerov1api.ServerStatusRequest
		reqPluginLister *fakePluginLister
		expected        *velerov1api.ServerStatusRequest
		expectedRequeue ctrl.Result
		expectedErrMsg  string
	}

	// `now` will be used to set the fake clock's time; capture
	// it here so it can be referenced in the test case defs.
	now, err := time.Parse(time.RFC1123, time.RFC1123)
	Expect(err).To(BeNil())
	now = now.Local()

	DescribeTable("a Server Status request",
		func(test request) {
			// Setup reconciler
			Expect(velerov1api.AddToScheme(scheme.Scheme)).To(Succeed())
			r := ServerStatusRequestReconciler{
				Client:         fake.NewFakeClientWithScheme(scheme.Scheme, test.req),
				Ctx:            context.Background(),
				PluginRegistry: test.reqPluginLister,
				Clock:          clock.NewFakeClock(now),
				Log:            velerotest.NewLogger(),
			}

			actualResult, err := r.Reconcile(r.Ctx, ctrl.Request{
				NamespacedName: types.NamespacedName{
					Namespace: velerov1api.DefaultNamespace,
					Name:      test.req.Name,
				},
			})

			Expect(actualResult).To(BeEquivalentTo(test.expectedRequeue))
			if test.expectedErrMsg == "" {
				Expect(err).To(BeNil())
			} else {
				Expect(err.Error()).To(BeEquivalentTo(test.expectedErrMsg))
				return
			}

			instance := &velerov1api.ServerStatusRequest{}
			err = r.Client.Get(ctx, kbclient.ObjectKey{Name: test.req.Name, Namespace: test.req.Namespace}, instance)

			// Assertions
			if test.expected == nil {
				Expect(apierrors.IsNotFound(err)).To(BeTrue())
			} else {
				Expect(err).To(BeNil())
				Eventually(instance.Status.Phase == test.expected.Status.Phase, timeout).Should(BeTrue())
			}
		},
		Entry("with phase=empty will be processed and phased successfully patched", request{
			req: statusRequestBuilder("1").
				ServerVersion(buildinfo.Version).
				ProcessedTimestamp(now).
				Plugins([]velerov1api.PluginInfo{
					{
						Name: "custom.io/myown",
						Kind: "VolumeSnapshotter",
					},
				}).
				Result(),
			reqPluginLister: &fakePluginLister{
				plugins: []framework.PluginIdentifier{
					{
						Name: "custom.io/myown",
						Kind: "VolumeSnapshotter",
					},
				},
			},
			expected: statusRequestBuilder("1").
				ServerVersion(buildinfo.Version).
				Phase(velerov1api.ServerStatusRequestPhaseProcessed).
				ProcessedTimestamp(now).
				Plugins([]velerov1api.PluginInfo{
					{
						Name: "custom.io/myown",
						Kind: "VolumeSnapshotter",
					},
				}).
				Result(),
			expectedRequeue: ctrl.Result{Requeue: false, RequeueAfter: statusRequestResyncPeriod},
		}),
		Entry("with phase=new will be processed and phased successfully patched", request{
			req: statusRequestBuilder("1").
				ServerVersion(buildinfo.Version).
				Phase(velerov1api.ServerStatusRequestPhaseNew).
				ProcessedTimestamp(now).
				Plugins([]velerov1api.PluginInfo{
					{
						Name: "custom.io/myown",
						Kind: "VolumeSnapshotter",
					},
				}).
				Result(),
			reqPluginLister: &fakePluginLister{
				plugins: []framework.PluginIdentifier{
					{
						Name: "custom.io/myown",
						Kind: "VolumeSnapshotter",
					},
				},
			},
			expected: statusRequestBuilder("1").
				ServerVersion(buildinfo.Version).
				Phase(velerov1api.ServerStatusRequestPhaseProcessed).
				ProcessedTimestamp(now).
				Plugins([]velerov1api.PluginInfo{
					{
						Name: "custom.io/myown",
						Kind: "VolumeSnapshotter",
					},
				}).
				Result(),
			expectedRequeue: ctrl.Result{Requeue: false, RequeueAfter: statusRequestResyncPeriod},
		}),
		Entry("with phase=Processed does not get deleted if not expired", request{
			req: statusRequestBuilder("1").
				ServerVersion(buildinfo.Version).
				Phase(velerov1api.ServerStatusRequestPhaseProcessed).
				ProcessedTimestamp(now). // not yet expired
				Plugins([]velerov1api.PluginInfo{
					{
						Name: "custom.io/myotherown",
						Kind: "VolumeSnapshotter",
					},
				}).
				Result(),
			reqPluginLister: &fakePluginLister{
				plugins: []framework.PluginIdentifier{
					{
						Name: "custom.io/myotherown",
						Kind: "VolumeSnapshotter",
					},
				},
			},
			expected: statusRequestBuilder("1").
				ServerVersion(buildinfo.Version).
				Phase(velerov1api.ServerStatusRequestPhaseProcessed).
				ProcessedTimestamp(now).
				Plugins([]velerov1api.PluginInfo{
					{
						Name: "custom.io/myown",
						Kind: "VolumeSnapshotter",
					},
				}).
				Result(),
			expectedRequeue: ctrl.Result{Requeue: false, RequeueAfter: statusRequestResyncPeriod},
		}),
		Entry("with phase=Processed gets deleted if expired", request{
			req: statusRequestBuilder("1").
				ServerVersion(buildinfo.Version).
				Phase(velerov1api.ServerStatusRequestPhaseProcessed).
				ProcessedTimestamp(now.Add(-61 * time.Second)). // expired
				Plugins([]velerov1api.PluginInfo{
					{
						Name: "custom.io/myotherown",
						Kind: "VolumeSnapshotter",
					},
				}).
				Result(),
			reqPluginLister: &fakePluginLister{
				plugins: []framework.PluginIdentifier{
					{
						Name: "custom.io/myotherown",
						Kind: "VolumeSnapshotter",
					},
				},
			},
			expected:        nil,
			expectedRequeue: ctrl.Result{Requeue: false, RequeueAfter: statusRequestResyncPeriod},
		}),
		Entry("with invalid phase returns an error and does not requeue", request{
			req: statusRequestBuilder("1").
				ServerVersion(buildinfo.Version).
				Phase("an-invalid-phase").
				ProcessedTimestamp(now).
				Plugins([]velerov1api.PluginInfo{
					{
						Name: "custom.io/myown",
						Kind: "VolumeSnapshotter",
					},
				}).
				Result(),
			reqPluginLister: &fakePluginLister{
				plugins: []framework.PluginIdentifier{
					{
						Name: "custom.io/myown",
						Kind: "VolumeSnapshotter",
					},
				},
			},
			expectedErrMsg:  "unexpected ServerStatusRequest phase",
			expectedRequeue: ctrl.Result{Requeue: false, RequeueAfter: 0},
		}),
	)
})

type fakePluginLister struct {
	plugins []framework.PluginIdentifier
}

func (l *fakePluginLister) List(kind framework.PluginKind) []framework.PluginIdentifier {
	var plugins []framework.PluginIdentifier
	for _, plugin := range l.plugins {
		if plugin.Kind == kind {
			plugins = append(plugins, plugin)
		}
	}

	return plugins
}