/*
Copyright 2022 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 webhooks

import (
	"fmt"
	log "log/slog"
	"path/filepath"

	"sigs.k8s.io/kubebuilder/v4/pkg/machinery"
)

var (
	_ machinery.Template = &WebhookSuite{}
	_ machinery.Inserter = &WebhookSuite{}
)

// WebhookSuite scaffolds the file that sets up the webhook tests
type WebhookSuite struct {
	machinery.TemplateMixin
	machinery.MultiGroupMixin
	machinery.BoilerplateMixin
	machinery.ResourceMixin

	// todo: currently is not possible to know if an API was or not scaffolded. We can fix it when #1826 be addressed
	WireResource bool

	// K8SVersion define the k8s version used to do the scaffold
	// so that is possible retrieve the binaries
	K8SVersion string

	// BaseDirectoryRelativePath define the Path for the base directory when it is multigroup
	BaseDirectoryRelativePath string
}

// SetTemplateDefaults implements machinery.Template
func (f *WebhookSuite) SetTemplateDefaults() error {
	if f.Path == "" {
		baseDir := filepath.Join("internal", "webhook")

		if f.MultiGroup && f.Resource.Group != "" {
			f.Path = filepath.Join(baseDir, "%[group]", "%[version]", "webhook_suite_test.go")
		} else {
			f.Path = filepath.Join(baseDir, "%[version]", "webhook_suite_test.go")
		}
	}

	f.Path = f.Resource.Replacer().Replace(f.Path)
	log.Info(f.Path)

	f.TemplateBody = fmt.Sprintf(webhookTestSuiteTemplate,
		machinery.NewMarkerFor(f.Path, importMarker),
		machinery.NewMarkerFor(f.Path, addSchemeMarker),
		machinery.NewMarkerFor(f.Path, addWebhookManagerMarker),
		"%s",
		"%d",
	)

	// If is multigroup the path needs to be ../../../../ since it has the group dir.
	f.BaseDirectoryRelativePath = `"..", "..", ".."`
	if f.MultiGroup && f.Resource.Group != "" {
		f.BaseDirectoryRelativePath = `"..", "..", "..", ".."`
	}

	return nil
}

const (
	importMarker            = "imports"
	addWebhookManagerMarker = "webhook"
	addSchemeMarker         = "scheme"
)

// GetMarkers implements file.Inserter
func (f *WebhookSuite) GetMarkers() []machinery.Marker {
	return []machinery.Marker{
		machinery.NewMarkerFor(f.Path, importMarker),
		machinery.NewMarkerFor(f.Path, addSchemeMarker),
		machinery.NewMarkerFor(f.Path, addWebhookManagerMarker),
	}
}

const (
	apiImportCodeFragment = `%s "%s"
`

	addSchemeCodeFragment = `err = %s.AddToScheme(scheme.Scheme)
Expect(err).NotTo(HaveOccurred())

`

	addWebhookManagerCodeFragment = `err = Setup%sWebhookWithManager(mgr)
Expect(err).NotTo(HaveOccurred())

`
)

// GetCodeFragments implements file.Inserter
func (f *WebhookSuite) GetCodeFragments() machinery.CodeFragmentsMap {
	fragments := make(machinery.CodeFragmentsMap, 3)

	// Generate import code fragments
	imports := make([]string, 0, 1)

	// Generate add scheme code fragments
	addScheme := make([]string, 0)

	// Generate add webhookManager code fragments
	addWebhookManager := make([]string, 0, 1)
	// The API import is only used by the AddToScheme call, so add both together.
	if f.Resource.Path != "" {
		imports = append(imports, fmt.Sprintf(apiImportCodeFragment, f.Resource.ImportAlias(), f.Resource.Path))
		addScheme = append(addScheme, fmt.Sprintf(addSchemeCodeFragment, f.Resource.ImportAlias()))
	}
	addWebhookManager = append(addWebhookManager, fmt.Sprintf(addWebhookManagerCodeFragment, f.Resource.Kind))

	// Only store code fragments in the map if the slices are non-empty
	if len(addWebhookManager) != 0 {
		fragments[machinery.NewMarkerFor(f.Path, addWebhookManagerMarker)] = addWebhookManager
	}
	if len(imports) != 0 {
		fragments[machinery.NewMarkerFor(f.Path, importMarker)] = imports
	}
	if len(addScheme) != 0 {
		fragments[machinery.NewMarkerFor(f.Path, addSchemeMarker)] = addScheme
	}

	return fragments
}

const webhookTestSuiteTemplate = `{{ .Boilerplate }}

package {{ .Resource.Version }}

import (
	"context"
	"crypto/tls"
	"fmt"
	"net"
	"os"
	"path/filepath"
	"testing"
	"time"

	. "github.com/onsi/ginkgo/v2"
	. "github.com/onsi/gomega"

	"k8s.io/client-go/kubernetes/scheme"
	"k8s.io/client-go/rest"
	ctrl "sigs.k8s.io/controller-runtime"
	"sigs.k8s.io/controller-runtime/pkg/client"
	"sigs.k8s.io/controller-runtime/pkg/envtest"
	logf "sigs.k8s.io/controller-runtime/pkg/log"
	metricsserver "sigs.k8s.io/controller-runtime/pkg/metrics/server"
	"sigs.k8s.io/controller-runtime/pkg/log/zap"
	%s
)

// These tests use Ginkgo (BDD-style Go testing framework). Refer to
// http://onsi.github.io/ginkgo/ to learn more about Ginkgo.

var (
	ctx context.Context
	cancel context.CancelFunc
	k8sClient client.Client
	cfg *rest.Config
	testEnv *envtest.Environment
)

func TestAPIs(t *testing.T) {
	RegisterFailHandler(Fail)

	RunSpecs(t, "Webhook Suite")
}

var _ = BeforeSuite(func() {
	logf.SetLogger(zap.New(zap.WriteTo(GinkgoWriter), zap.UseDevMode(true)))

	ctx, cancel = context.WithCancel(context.TODO())

	var err error
	%s

	By("bootstrapping test environment")
	testEnv = &envtest.Environment{
		CRDDirectoryPaths:     []string{filepath.Join({{ .BaseDirectoryRelativePath }}, "config", "crd", "bases")},
		ErrorIfCRDPathMissing: {{ .WireResource }},

		WebhookInstallOptions: envtest.WebhookInstallOptions{
			Paths: []string{filepath.Join({{ .BaseDirectoryRelativePath }}, "config", "webhook")},
		},
	}

	// Retrieve the first found binary directory to allow running tests from IDEs
	if getFirstFoundEnvTestBinaryDir() != "" {
		testEnv.BinaryAssetsDirectory = getFirstFoundEnvTestBinaryDir()
	}

	// cfg is defined in this file globally.
	cfg, err = testEnv.Start()
	Expect(err).NotTo(HaveOccurred())
	Expect(cfg).NotTo(BeNil())

	k8sClient, err = client.New(cfg, client.Options{Scheme: scheme.Scheme})
	Expect(err).NotTo(HaveOccurred())
	Expect(k8sClient).NotTo(BeNil())

	// start webhook server using Manager.
	webhookInstallOptions := &testEnv.WebhookInstallOptions
	mgr, err := ctrl.NewManager(cfg, ctrl.Options{
		Scheme:             scheme.Scheme,
		WebhookServer: webhook.NewServer(webhook.Options{
			Host:               webhookInstallOptions.LocalServingHost,
			Port:               webhookInstallOptions.LocalServingPort,
			CertDir:            webhookInstallOptions.LocalServingCertDir,
		}),
		LeaderElection:     false,
		Metrics:            metricsserver.Options{BindAddress: "0"},

	})
	Expect(err).NotTo(HaveOccurred())

	%s

	go func() {
		defer GinkgoRecover()
		err = mgr.Start(ctx)
		Expect(err).NotTo(HaveOccurred())
	}()

	// wait for the webhook server to get ready.
	dialer := &net.Dialer{Timeout: time.Second}
	addrPort := fmt.Sprintf("%s:%s", webhookInstallOptions.LocalServingHost, webhookInstallOptions.LocalServingPort)
	Eventually(func() error {
		conn, err := tls.DialWithDialer(dialer, "tcp", addrPort, &tls.Config{InsecureSkipVerify: true})
		if err != nil {
			return err
		}

		return conn.Close();
	}).Should(Succeed())
})

var _ = AfterSuite(func() {
	By("tearing down the test environment")
	cancel()
	err := testEnv.Stop()
	Expect(err).NotTo(HaveOccurred())
})

// getFirstFoundEnvTestBinaryDir locates the first binary in the specified path.
// ENVTEST-based tests depend on specific binaries, usually located in paths set by
// controller-runtime. When running tests directly (e.g., via an IDE) without using
// Makefile targets, the 'BinaryAssetsDirectory' must be explicitly configured.
//
// This function streamlines the process by finding the required binaries, similar to
// setting the 'KUBEBUILDER_ASSETS' environment variable. To ensure the binaries are 
// properly set up, run 'make setup-envtest' beforehand.
func getFirstFoundEnvTestBinaryDir() string {
	basePath := filepath.Join({{ .BaseDirectoryRelativePath }}, "bin", "k8s")
	entries, err := os.ReadDir(basePath)
	if err != nil {
		logf.Log.Error(err, "Failed to read directory", "path", basePath)
		return ""
	}
	for _, entry := range entries {
		if entry.IsDir() {
			return filepath.Join(basePath, entry.Name())
		}
	}
	return ""
}
`
