/*
Copyright 2014 Google Inc. All rights reserved.

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 kubectl

import (
	"bytes"
	"fmt"
	"testing"
	"time"

	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
	"github.com/GoogleCloudPlatform/kubernetes/pkg/client"
)

type customFake struct {
	*client.Fake
	ctrl client.ReplicationControllerInterface
}

func (c *customFake) ReplicationControllers(namespace string) client.ReplicationControllerInterface {
	return c.ctrl
}

func fakeClientFor(namespace string, responses []fakeResponse) client.Interface {
	fake := client.Fake{}
	return &customFake{
		&fake,
		&fakeRc{
			&client.FakeReplicationControllers{
				Fake:      &fake,
				Namespace: namespace,
			},
			responses,
		},
	}
}

type fakeResponse struct {
	controller *api.ReplicationController
	err        error
}

type fakeRc struct {
	*client.FakeReplicationControllers
	responses []fakeResponse
}

func (c *fakeRc) Get(name string) (*api.ReplicationController, error) {
	action := client.FakeAction{Action: "get-controller", Value: name}
	if len(c.responses) == 0 {
		return nil, fmt.Errorf("Unexpected Action: %s", action)
	}
	c.Fake.Actions = append(c.Fake.Actions, action)
	result := c.responses[0]
	c.responses = c.responses[1:]
	return result.controller, result.err
}

func (c *fakeRc) Create(controller *api.ReplicationController) (*api.ReplicationController, error) {
	c.Fake.Actions = append(c.Fake.Actions, client.FakeAction{Action: "create-controller", Value: controller.ObjectMeta.Name})
	return controller, nil
}

func (c *fakeRc) Update(controller *api.ReplicationController) (*api.ReplicationController, error) {
	c.Fake.Actions = append(c.Fake.Actions, client.FakeAction{Action: "update-controller", Value: controller.ObjectMeta.Name})
	return controller, nil
}

func oldRc(replicas int) *api.ReplicationController {
	return &api.ReplicationController{
		ObjectMeta: api.ObjectMeta{
			Name: "foo-v1",
			UID:  "7764ae47-9092-11e4-8393-42010af018ff",
		},
		Spec: api.ReplicationControllerSpec{
			Replicas: replicas,
			Selector: map[string]string{"version": "v1"},
			Template: &api.PodTemplateSpec{
				ObjectMeta: api.ObjectMeta{
					Name:   "foo-v1",
					Labels: map[string]string{"version": "v1"},
				},
			},
		},
		Status: api.ReplicationControllerStatus{
			Replicas: replicas,
		},
	}
}

func newRc(replicas int, desired int) *api.ReplicationController {
	rc := oldRc(replicas)
	rc.Spec.Template = &api.PodTemplateSpec{
		ObjectMeta: api.ObjectMeta{
			Name:   "foo-v2",
			Labels: map[string]string{"version": "v2"},
		},
	}
	rc.Spec.Selector = map[string]string{"version": "v2"}
	rc.ObjectMeta = api.ObjectMeta{
		Name: "foo-v2",
		Annotations: map[string]string{
			desiredReplicasAnnotation: fmt.Sprintf("%d", desired),
			sourceIdAnnotation:        "foo-v1:7764ae47-9092-11e4-8393-42010af018ff",
		},
	}
	return rc
}

func TestUpdate(t *testing.T) {
	tests := []struct {
		oldRc, newRc *api.ReplicationController
		responses    []fakeResponse
		output       string
	}{
		{
			oldRc(1), newRc(1, 1),
			[]fakeResponse{
				// no existing newRc
				{nil, fmt.Errorf("not found")},
				// one update round
				{newRc(1, 1), nil},
				{newRc(1, 1), nil},
				{oldRc(0), nil},
				{oldRc(0), nil},
				// get newRc after final update (to cleanup annotations)
				{newRc(1, 1), nil},
				{newRc(1, 1), nil},
			},
			`Creating foo-v2
Updating foo-v1 replicas: 0, foo-v2 replicas: 1
Update succeeded. Deleting foo-v1
`,
		}, {
			oldRc(2), newRc(2, 2),
			[]fakeResponse{
				// no existing newRc
				{nil, fmt.Errorf("not found")},
				// 2 gets for each update (poll for condition, refetch)
				{newRc(1, 2), nil},
				{newRc(1, 2), nil},
				{oldRc(1), nil},
				{oldRc(1), nil},
				{newRc(2, 2), nil},
				{newRc(2, 2), nil},
				{oldRc(0), nil},
				{oldRc(0), nil},
				// get newRc after final update (cleanup annotations)
				{newRc(2, 2), nil},
				{newRc(2, 2), nil},
			},
			`Creating foo-v2
Updating foo-v1 replicas: 1, foo-v2 replicas: 1
Updating foo-v1 replicas: 0, foo-v2 replicas: 2
Update succeeded. Deleting foo-v1
`,
		}, {
			oldRc(2), newRc(7, 7),
			[]fakeResponse{
				// no existing newRc
				{nil, fmt.Errorf("not found")},
				// 2 gets for each update (poll for condition, refetch)
				{newRc(1, 2), nil},
				{newRc(1, 2), nil},
				{oldRc(1), nil},
				{oldRc(1), nil},
				{newRc(2, 2), nil},
				{newRc(2, 2), nil},
				{oldRc(0), nil},
				{oldRc(0), nil},
				// final update on newRc (resize + cleanup annotations)
				{newRc(7, 7), nil},
				{newRc(7, 7), nil},
			},
			`Creating foo-v2
Updating foo-v1 replicas: 1, foo-v2 replicas: 1
Updating foo-v1 replicas: 0, foo-v2 replicas: 2
Resizing foo-v2 replicas: 2 -> 7
Update succeeded. Deleting foo-v1
`,
		}, {
			oldRc(7), newRc(2, 2),
			[]fakeResponse{
				// no existing newRc
				{nil, fmt.Errorf("not found")},
				// 2 gets for each update (poll for condition, refetch)
				{newRc(1, 2), nil},
				{newRc(1, 2), nil},
				{oldRc(6), nil},
				{oldRc(6), nil},
				{newRc(2, 2), nil},
				{newRc(2, 2), nil},
				{oldRc(5), nil},
				{oldRc(5), nil},
				// stop oldRc
				{oldRc(0), nil},
				{oldRc(0), nil},
				// final update on newRc (cleanup annotations)
				{newRc(2, 2), nil},
				{newRc(2, 2), nil},
			},
			`Creating foo-v2
Updating foo-v1 replicas: 6, foo-v2 replicas: 1
Updating foo-v1 replicas: 5, foo-v2 replicas: 2
Stopping foo-v1 replicas: 5 -> 0
Update succeeded. Deleting foo-v1
`,
		},
	}

	for _, test := range tests {
		updater := RollingUpdater{
			fakeClientFor("default", test.responses),
			"default",
		}
		var buffer bytes.Buffer

		if err := updater.Update(&buffer, test.oldRc, test.newRc, 0, 1*time.Millisecond, 1*time.Millisecond); err != nil {
			t.Errorf("Update failed: %v", err)
		}
		if buffer.String() != test.output {
			t.Errorf("Bad output. expected:\n%s\ngot:\n%s", test.output, buffer.String())
		}
	}
}

func TestUpdateRecovery(t *testing.T) {
	// Test recovery from interruption
	rc := oldRc(2)
	rcExisting := newRc(1, 3)

	output := `Continuing update with existing controller foo-v2.
Updating foo-v1 replicas: 1, foo-v2 replicas: 2
Updating foo-v1 replicas: 0, foo-v2 replicas: 3
Update succeeded. Deleting foo-v1
`
	responses := []fakeResponse{
		// Existing newRc
		{rcExisting, nil},
		// 2 gets for each update (poll for condition, refetch)
		{newRc(2, 2), nil},
		{newRc(2, 2), nil},
		{oldRc(1), nil},
		{oldRc(1), nil},
		{newRc(3, 3), nil},
		{newRc(3, 3), nil},
		{oldRc(0), nil},
		{oldRc(0), nil},
		// get newRc after final update (cleanup annotations)
		{newRc(3, 3), nil},
		{newRc(3, 3), nil},
	}
	updater := RollingUpdater{fakeClientFor("default", responses), "default"}

	var buffer bytes.Buffer
	if err := updater.Update(&buffer, rc, rcExisting, 0, 1*time.Millisecond, 1*time.Millisecond); err != nil {
		t.Errorf("Update failed: %v", err)
	}
	if buffer.String() != output {
		t.Errorf("Output was not as expected. Expected:\n%s\nGot:\n%s", output, buffer.String())
	}
}