/*
Copyright 2021 The KubeEdge Authors.
Copyright 2015 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 framework

import (
	"context"
	"fmt"
	"strings"

	"github.com/onsi/ginkgo"
	"github.com/onsi/gomega"
	v1 "k8s.io/api/core/v1"
	apierrors "k8s.io/apimachinery/pkg/api/errors"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime/schema"
	clientset "k8s.io/client-go/kubernetes"
	"k8s.io/client-go/rest"

	sednaclientset "github.com/kubeedge/sedna/pkg/client/clientset/versioned"
)

// Framework supports common operations used by e2e tests; it will keep a client & a namespace for you.
// Eventual goal is to merge this with integration test framework.
type Framework struct {
	BaseName string

	// Set together with creating the ClientSet and the namespace.
	// Guaranteed to be unique in the cluster even when running the same
	// test multiple times in parallel.
	UniqueName string

	SednaClientSet sednaclientset.Interface
	ClientSet      clientset.Interface

	SkipNamespaceCreation bool            // Whether to skip creating a namespace
	Namespace             *v1.Namespace   // Every test has at least one namespace unless creation is skipped
	namespacesToDelete    []*v1.Namespace // Some tests have more than one.

	// To make sure that this framework cleans up after itself, no matter what,
	// we install a Cleanup action before each test and clear it after.  If we
	// should abort, the AfterSuite hook should run all Cleanup actions.
	cleanupHandle CleanupActionHandle

	// configuration for framework's client
	Options Options

	AfterEachActions []func()
}

// Options contains some options
type Options struct {
	ClientQPS    float32
	ClientBurst  int
	GroupVersion *schema.GroupVersion
}

// NewDefaultFramework makes a new framework and sets up a BeforeEach/AfterEach for
// you (you can write additional before/after each functions).
func NewDefaultFramework(baseName string) *Framework {
	options := Options{
		ClientQPS:   20,
		ClientBurst: 50,
	}
	return NewFramework(baseName, options, nil)
}

// NewFramework makes a new framework and sets up a BeforeEach/AfterEach
func NewFramework(baseName string, options Options, client clientset.Interface) *Framework {
	f := &Framework{
		BaseName:  baseName,
		Options:   options,
		ClientSet: client,
	}

	ginkgo.BeforeEach(f.BeforeEach)
	ginkgo.AfterEach(f.AfterEach)

	return f
}

// BeforeEach gets a client and makes a namespace.
func (f *Framework) BeforeEach() {
	// The fact that we need this feels like a bug in ginkgo.
	// https://github.com/onsi/ginkgo/issues/222
	f.cleanupHandle = AddCleanupAction(f.AfterEach)
	if f.ClientSet == nil {
		ginkgo.By("Creating a kubernetes client")
		config, err := LoadConfig()
		gomega.Expect(err).NotTo(gomega.HaveOccurred())
		testDesc := ginkgo.CurrentGinkgoTestDescription()
		if len(testDesc.ComponentTexts) > 0 {
			componentTexts := strings.Join(testDesc.ComponentTexts, " ")
			config.UserAgent = fmt.Sprintf(
				"%v -- %v",
				rest.DefaultKubernetesUserAgent(),
				componentTexts)
		}

		config.QPS = f.Options.ClientQPS
		config.Burst = f.Options.ClientBurst
		if f.Options.GroupVersion != nil {
			config.GroupVersion = f.Options.GroupVersion
		}

		f.ClientSet, err = clientset.NewForConfig(config)
		gomega.Expect(err).NotTo(gomega.HaveOccurred())

		// sedna.io is based on CRD, which is served only as JSON
		jsonConfig := config
		jsonConfig.ContentType = "application/json"
		f.SednaClientSet, err = sednaclientset.NewForConfig(jsonConfig)
		gomega.Expect(err).NotTo(gomega.HaveOccurred())
	}

	if !f.SkipNamespaceCreation {
		ginkgo.By(fmt.Sprintf("Building a namespace api object, basename %s", f.BaseName))
		namespace, err := f.CreateNamespace(f.BaseName, map[string]string{
			"e2e-framework": f.BaseName,
		})
		gomega.Expect(err).NotTo(gomega.HaveOccurred())

		f.Namespace = namespace

		f.UniqueName = f.Namespace.GetName()
	} else {
		// not guaranteed to be unique, but very likely
		f.UniqueName = f.BaseName + "-" + RandomSuffix()
	}
}

// AfterEach deletes the namespace, after reading its events.
func (f *Framework) AfterEach() {
	RemoveCleanupAction(f.cleanupHandle)

	// DeleteNamespace at the very end in defer, to avoid any
	// expectation failures preventing deleting the namespace.
	defer func() {
		nsDeletionErrors := map[string]error{}
		// Whether to delete namespace is determined by 3 factors: delete-namespace flag, delete-namespace-on-failure flag and the test result
		// if delete-namespace set to false, namespace will always be preserved.
		// if delete-namespace is true and delete-namespace-on-failure is false, namespace will be preserved if test failed.
		if TestContext.DeleteNamespace && (TestContext.DeleteNamespaceOnFailure || !ginkgo.CurrentGinkgoTestDescription().Failed) {
			for _, ns := range f.namespacesToDelete {
				ginkgo.By(fmt.Sprintf("Destroying namespace %q for this suite.", ns.Name))
				if err := f.ClientSet.CoreV1().Namespaces().Delete(context.TODO(), ns.Name, metav1.DeleteOptions{}); err != nil {
					if !apierrors.IsNotFound(err) {
						nsDeletionErrors[ns.Name] = err
					} else {
						Logf("Namespace %v was already deleted", ns.Name)
					}
				}
			}
		} else {
			if !TestContext.DeleteNamespace {
				Logf("Found DeleteNamespace=false, skipping namespace deletion!")
			} else {
				Logf("Found DeleteNamespaceOnFailure=false and current test failed, skipping namespace deletion!")
			}
		}

		// Paranoia-- prevent reuse!
		f.Namespace = nil
		f.SednaClientSet = nil
		f.ClientSet = nil
		f.namespacesToDelete = nil

		// if we had errors deleting, report them now.
		if len(nsDeletionErrors) != 0 {
			messages := []string{}
			for namespaceKey, namespaceErr := range nsDeletionErrors {
				messages = append(messages, fmt.Sprintf("Couldn't delete ns: %q: %s (%#v)", namespaceKey, namespaceErr, namespaceErr))
			}
			Failf(strings.Join(messages, ","))
		}
	}()

	for _, f := range f.AfterEachActions {
		f()
	}
}

// CreateNamespace is used to create namespace
func (f *Framework) CreateNamespace(baseName string, labels map[string]string) (*v1.Namespace, error) {
	ns, err := CreateTestingNS(baseName, f.ClientSet, labels)
	// check ns instead of err to see if it's nil as we may
	// fail to create serviceAccount in it.
	f.AddNamespacesToDelete(ns)

	return ns, err
}

// AddNamespacesToDelete adds one or more namespaces to be deleted when the test
// completes.
func (f *Framework) AddNamespacesToDelete(namespaces ...*v1.Namespace) {
	for _, ns := range namespaces {
		if ns == nil {
			continue
		}
		f.namespacesToDelete = append(f.namespacesToDelete, ns)
	}
}