package addontemplate

import (
	"context"
	"sync"
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/client-go/dynamic/dynamicinformer"
	dynamicfake "k8s.io/client-go/dynamic/fake"
	fakekube "k8s.io/client-go/kubernetes/fake"
	"k8s.io/client-go/rest"
	"k8s.io/client-go/tools/cache"

	"open-cluster-management.io/addon-framework/pkg/addonmanager/addontesting"
	"open-cluster-management.io/addon-framework/pkg/utils"
	addonv1beta1 "open-cluster-management.io/api/addon/v1beta1"
	fakeaddon "open-cluster-management.io/api/client/addon/clientset/versioned/fake"
	addoninformers "open-cluster-management.io/api/client/addon/informers/externalversions"
	fakecluster "open-cluster-management.io/api/client/cluster/clientset/versioned/fake"
	clusterv1informers "open-cluster-management.io/api/client/cluster/informers/externalversions"
	fakework "open-cluster-management.io/api/client/work/clientset/versioned/fake"
	workinformers "open-cluster-management.io/api/client/work/informers/externalversions"

	addonindex "open-cluster-management.io/ocm/pkg/addon/index"
	testingcommon "open-cluster-management.io/ocm/pkg/common/testing"
	testinghelpers "open-cluster-management.io/ocm/pkg/registration/helpers/testing"
)

func TestReconcile(t *testing.T) {
	cases := []struct {
		name                   string
		syncKeys               []string
		managedClusteraddon    []runtime.Object
		clusterManagementAddon []runtime.Object
		expectedCount          int
		expectedTimeout        bool
	}{
		{
			name:                   "no clustermanagementaddon",
			syncKeys:               []string{"test"},
			managedClusteraddon:    []runtime.Object{},
			clusterManagementAddon: []runtime.Object{},
			expectedCount:          0,
			expectedTimeout:        true,
		},
		{
			name:                "not template type clustermanagementaddon",
			syncKeys:            []string{"test"},
			managedClusteraddon: []runtime.Object{},
			clusterManagementAddon: []runtime.Object{
				addontesting.NewClusterManagementAddon("test", "", "").Build()},
			expectedCount:   0,
			expectedTimeout: true,
		},
		{
			name:                "one template type clustermanagementaddon",
			syncKeys:            []string{"test"},
			managedClusteraddon: []runtime.Object{},
			clusterManagementAddon: []runtime.Object{
				addontesting.NewClusterManagementAddon("test", "", "").WithDefaultConfigs(
					addonv1beta1.AddOnConfig{
						ConfigGroupResource: addonv1beta1.ConfigGroupResource{
							Group:    utils.AddOnTemplateGVR.Group,
							Resource: utils.AddOnTemplateGVR.Resource,
						},
						ConfigReferent: addonv1beta1.ConfigReferent{Name: "test"},
					}).Build()},
			expectedCount:   1,
			expectedTimeout: false,
		},
		{
			name:                "two template type clustermanagementaddon",
			syncKeys:            []string{"test", "test1"},
			managedClusteraddon: []runtime.Object{},
			clusterManagementAddon: []runtime.Object{
				addontesting.NewClusterManagementAddon("test", "", "").WithDefaultConfigs(
					addonv1beta1.AddOnConfig{
						ConfigGroupResource: addonv1beta1.ConfigGroupResource{
							Group:    utils.AddOnTemplateGVR.Group,
							Resource: utils.AddOnTemplateGVR.Resource,
						},
						ConfigReferent: addonv1beta1.ConfigReferent{Name: "test"},
					}).Build(),
				addontesting.NewClusterManagementAddon("test1", "", "").WithDefaultConfigs(
					addonv1beta1.AddOnConfig{
						ConfigGroupResource: addonv1beta1.ConfigGroupResource{
							Group:    utils.AddOnTemplateGVR.Group,
							Resource: utils.AddOnTemplateGVR.Resource,
						},
						ConfigReferent: addonv1beta1.ConfigReferent{Name: "test"},
					}).Build(),
			},
			expectedCount:   2,
			expectedTimeout: false,
		},
		{
			name:                "two template type and one not template type clustermanagementaddon",
			syncKeys:            []string{"test", "test1", "test2"},
			managedClusteraddon: []runtime.Object{},
			clusterManagementAddon: []runtime.Object{
				addontesting.NewClusterManagementAddon("test", "", "").WithDefaultConfigs(
					addonv1beta1.AddOnConfig{
						ConfigGroupResource: addonv1beta1.ConfigGroupResource{
							Group:    utils.AddOnTemplateGVR.Group,
							Resource: utils.AddOnTemplateGVR.Resource,
						},
						ConfigReferent: addonv1beta1.ConfigReferent{Name: "test"},
					}).Build(),
				addontesting.NewClusterManagementAddon("test1", "", "").WithDefaultConfigs(
					addonv1beta1.AddOnConfig{
						ConfigGroupResource: addonv1beta1.ConfigGroupResource{
							Group:    utils.AddOnTemplateGVR.Group,
							Resource: utils.AddOnTemplateGVR.Resource,
						},
						ConfigReferent: addonv1beta1.ConfigReferent{Name: "test"},
					}).Build(),
				addontesting.NewClusterManagementAddon("test2", "", "").Build(),
			},
			expectedCount:   2,
			expectedTimeout: true,
		},
	}

	for _, c := range cases {
		count := 0
		var wg sync.WaitGroup
		lock := &sync.Mutex{}
		rederCount := func() int {
			lock.Lock()
			defer lock.Unlock()
			return count
		}
		increaseCount := func() {
			lock.Lock()
			defer lock.Unlock()
			count++
		}

		for range c.syncKeys {
			wg.Add(1)
		}
		runController := func(ctx context.Context, addonName string) error {
			defer wg.Done()
			increaseCount()
			return nil
		}
		obj := append(c.clusterManagementAddon, c.managedClusteraddon...) //nolint:gocritic
		fakeAddonClient := fakeaddon.NewSimpleClientset(obj...)

		addonInformers := addoninformers.NewSharedInformerFactory(fakeAddonClient, 10*time.Minute)

		// Add the index for ManagedClusterAddonByName
		err := addonInformers.Addon().V1beta1().ManagedClusterAddOns().Informer().AddIndexers(
			cache.Indexers{
				addonindex.ManagedClusterAddonByName: addonindex.IndexManagedClusterAddonByName,
			})
		if err != nil {
			t.Fatal(err)
		}

		for _, obj := range c.managedClusteraddon {
			if err := addonInformers.Addon().V1beta1().ManagedClusterAddOns().Informer().GetStore().Add(obj); err != nil {
				t.Fatal(err)
			}
		}
		for _, obj := range c.clusterManagementAddon {
			if err := addonInformers.Addon().V1beta1().ClusterManagementAddOns().Informer().GetStore().Add(obj); err != nil {
				t.Fatal(err)
			}
		}

		fakeDynamicClient := dynamicfake.NewSimpleDynamicClient(runtime.NewScheme())
		dynamicInformerFactory := dynamicinformer.NewDynamicSharedInformerFactory(fakeDynamicClient, 0)

		fakeClusterClient := fakecluster.NewSimpleClientset()
		clusterInformers := clusterv1informers.NewSharedInformerFactory(fakeClusterClient, 10*time.Minute)

		fakeWorkClient := fakework.NewSimpleClientset()
		workInformers := workinformers.NewSharedInformerFactory(fakeWorkClient, 10*time.Minute)

		hubKubeClient := fakekube.NewSimpleClientset()

		controller := NewAddonTemplateController(
			nil,
			hubKubeClient,
			fakeAddonClient,
			fakeWorkClient,
			addonInformers,
			clusterInformers,
			dynamicInformerFactory,
			workInformers,
			runController,
		)
		ctx := context.TODO()
		for _, syncKey := range c.syncKeys {
			syncContext := testingcommon.NewFakeSyncContext(t, syncKey)
			err := controller.Sync(ctx, syncContext, syncKey)
			if err != nil {
				t.Errorf("expected no error when sync: %v", err)
			}
		}

		ch := make(chan struct{})
		go func() {
			defer close(ch)
			wg.Wait()
		}()

		select {
		case <-ch:
			actualCount := rederCount()
			if actualCount != c.expectedCount {
				t.Errorf("name : %s, expected runControllerFunc to be called %d, but was called %d times",
					c.name, c.expectedCount, actualCount)
			}
		case <-time.After(1 * time.Second):
			if !c.expectedTimeout {
				t.Errorf("name : %s, expected not timeout, but timeout", c.name)
			}
			actualCount := rederCount()
			if actualCount != c.expectedCount {
				t.Errorf("name : %s, expected runControllerFunc to be called %d, but was called %d times",
					c.name, c.expectedCount, actualCount)
			}
		}
	}
}

func TestRunController(t *testing.T) {
	cases := []struct {
		name        string
		addonName   string
		expectedErr string
	}{
		{
			name:        "addon name empty",
			addonName:   "",
			expectedErr: "addon name should be set",
		},
		{
			name:      "fake kubeconfig",
			addonName: "test",
		},
	}

	for _, c := range cases {
		fakeAddonClient := fakeaddon.NewSimpleClientset()
		addonInformers := addoninformers.NewSharedInformerFactory(fakeAddonClient, 10*time.Minute)
		fakeDynamicClient := dynamicfake.NewSimpleDynamicClient(runtime.NewScheme())
		dynamicInformerFactory := dynamicinformer.NewDynamicSharedInformerFactory(fakeDynamicClient, 0)
		fakeClusterClient := fakecluster.NewSimpleClientset()
		clusterInformers := clusterv1informers.NewSharedInformerFactory(fakeClusterClient, 10*time.Minute)
		fakeWorkClient := fakework.NewSimpleClientset()
		workInformers := workinformers.NewSharedInformerFactory(fakeWorkClient, 10*time.Minute)
		hubKubeClient := fakekube.NewSimpleClientset()
		controller := &addonTemplateController{
			kubeConfig:                 &rest.Config{},
			kubeClient:                 hubKubeClient,
			addonClient:                fakeAddonClient,
			cmaLister:                  addonInformers.Addon().V1beta1().ClusterManagementAddOns().Lister(),
			managedClusterAddonIndexer: addonInformers.Addon().V1beta1().ManagedClusterAddOns().Informer().GetIndexer(),
			addonManagers:              make(map[string]context.CancelFunc),
			addonInformers:             addonInformers,
			clusterInformers:           clusterInformers,
			dynamicInformers:           dynamicInformerFactory,
			workInformers:              workInformers,
		}
		ctx := context.TODO()

		err := controller.runController(ctx, c.addonName)
		if err == nil {
			assert.Empty(t, c.expectedErr)
		} else {
			assert.Contains(t, err.Error(), c.expectedErr, "name : %s, expected error %v, but got %v", c.name, c.expectedErr, err)
		}
	}
}

func TestStopUnusedManagers(t *testing.T) {
	cases := []struct {
		name                   string
		addonName              string
		managedClusterAddons   []runtime.Object
		existingManagers       map[string]context.CancelFunc
		expectedManagerStopped bool
		expectedRequeue        bool
	}{
		{
			name:                 "no managed cluster addons, manager should be stopped",
			addonName:            "test-addon",
			managedClusterAddons: []runtime.Object{},
			existingManagers: map[string]context.CancelFunc{
				"test-addon": func() {},
			},
			expectedManagerStopped: true,
			expectedRequeue:        false,
		},
		{
			name:      "managed cluster addons exist, manager should not be stopped",
			addonName: "test-addon",
			managedClusterAddons: []runtime.Object{
				testinghelpers.NewManagedClusterAddons("test-addon", "cluster1", nil, nil),
			},
			existingManagers: map[string]context.CancelFunc{
				"test-addon": func() {},
			},
			expectedManagerStopped: false,
			expectedRequeue:        true,
		},
		{
			name:      "multiple managed cluster addons exist, manager should not be stopped",
			addonName: "test-addon",
			managedClusterAddons: []runtime.Object{
				testinghelpers.NewManagedClusterAddons("test-addon", "cluster1", nil, nil),
				testinghelpers.NewManagedClusterAddons("test-addon", "cluster2", nil, nil),
			},
			existingManagers: map[string]context.CancelFunc{
				"test-addon": func() {},
			},
			expectedManagerStopped: false,
			expectedRequeue:        true,
		},
		{
			name:                   "no manager exists, should not error",
			addonName:              "test-addon",
			managedClusterAddons:   []runtime.Object{},
			existingManagers:       map[string]context.CancelFunc{},
			expectedManagerStopped: false,
			expectedRequeue:        false,
		},
	}

	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			fakeAddonClient := fakeaddon.NewSimpleClientset(c.managedClusterAddons...)
			addonInformers := addoninformers.NewSharedInformerFactory(fakeAddonClient, 10*time.Minute)

			fakeDynamicClient := dynamicfake.NewSimpleDynamicClient(runtime.NewScheme())
			dynamicInformerFactory := dynamicinformer.NewDynamicSharedInformerFactory(fakeDynamicClient, 0)
			fakeClusterClient := fakecluster.NewSimpleClientset()
			clusterInformers := clusterv1informers.NewSharedInformerFactory(fakeClusterClient, 10*time.Minute)
			fakeWorkClient := fakework.NewSimpleClientset()
			workInformers := workinformers.NewSharedInformerFactory(fakeWorkClient, 10*time.Minute)
			hubKubeClient := fakekube.NewSimpleClientset()

			managerStopped := false
			existingManagers := make(map[string]context.CancelFunc)
			for name, stopFunc := range c.existingManagers {
				capturedName := name
				capturedStopFunc := stopFunc
				existingManagers[name] = func() {
					if capturedName == c.addonName {
						managerStopped = true
					}
					capturedStopFunc()
				}
			}

			// Add the index for ManagedClusterAddonByName
			err := addonInformers.Addon().V1beta1().ManagedClusterAddOns().Informer().AddIndexers(
				cache.Indexers{
					addonindex.ManagedClusterAddonByName: addonindex.IndexManagedClusterAddonByName,
				})
			if err != nil {
				t.Fatal(err)
			}

			controller := &addonTemplateController{
				kubeConfig:                 &rest.Config{},
				kubeClient:                 hubKubeClient,
				addonClient:                fakeAddonClient,
				workClient:                 fakeWorkClient,
				cmaLister:                  addonInformers.Addon().V1beta1().ClusterManagementAddOns().Lister(),
				managedClusterAddonIndexer: addonInformers.Addon().V1beta1().ManagedClusterAddOns().Informer().GetIndexer(),
				addonManagers:              existingManagers,
				addonInformers:             addonInformers,
				clusterInformers:           clusterInformers,
				dynamicInformers:           dynamicInformerFactory,
				workInformers:              workInformers,
			}

			// Start informers and wait for cache sync
			ctx := context.TODO()
			addonInformers.Start(ctx.Done())
			addonInformers.WaitForCacheSync(ctx.Done())

			syncContext := testingcommon.NewFakeSyncContext(t, c.addonName)

			err = controller.stopUnusedManagers(ctx, syncContext, c.addonName)
			assert.NoError(t, err)
			// Check if manager was stopped
			if c.expectedManagerStopped {
				assert.True(t, managerStopped, "expected manager to be stopped")
				_, exists := controller.addonManagers[c.addonName]
				assert.False(t, exists, "expected manager to be removed from map")
			} else {
				assert.False(t, managerStopped, "expected manager not to be stopped")
				if len(c.existingManagers) > 0 {
					_, exists := controller.addonManagers[c.addonName]
					assert.True(t, exists, "expected manager to still exist in map")
				}
			}

			// Check if requeue was called
			if c.expectedRequeue {
				// We can't easily test the exact requeue behavior with the fake sync context
				// but we can verify the manager wasn't stopped when it should be requeued
				assert.False(t, managerStopped, "manager should not be stopped when requeue is expected")
			}
		})
	}
}