// /*
// 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 webhook

import (
	"context"
	b64 "encoding/base64"
	"net/http"
	"net/http/httptest"
	"testing"

	corev1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"sigs.k8s.io/controller-runtime/pkg/client"
	"sigs.k8s.io/controller-runtime/pkg/client/fake"

	esv1 "github.com/external-secrets/external-secrets/apis/externalsecrets/v1"
	esmeta "github.com/external-secrets/external-secrets/apis/meta/v1"
)

type mockAuthTestPackage struct {
	Creds      mockCreds
	MockServer mockAuthTestServer
	Request    mockAuthRequest
	Expect     string
}

type mockCreds struct {
	UserName string
	Password string
}

type mockAuthTestServer func(
	serverCreds mockCreds,
	t *testing.T) *httptest.Server

type mockAuthRequest func(
	url string,
	creds mockCreds,
	t *testing.T) string

func TestWebhookAuth(t *testing.T) {
	// define test cases
	creds := mockCreds{"correctuser123", "correctpassword123"}
	basicAuthExpect := "Basic " + b64.StdEncoding.EncodeToString([]byte(creds.UserName+":"+creds.Password))
	ntlmExpect := "NTLM TlRMTVNTUAABAAAAAQCIoAAAAAAoAAAAAAAAACgAAAAGAbEdAAAADw=="
	negotiateExpect := "Negotiate TlRMTVNTUAABAAAAAQCIoAAAAAAoAAAAAAAAACgAAAAGAbEdAAAADw=="

	// due to integrated nature of GetSecret(), we use a mock server
	// to return relevant parts of a request, in this case, the auth header.
	testAuthHeaders := map[string]mockAuthTestPackage{
		"BasicAuth": {creds, basicAuthRequestEcho, basicAuthRequest, basicAuthExpect},
		"NTLM":      {creds, ntlmRequestEcho, ntlmRequest, ntlmExpect},
		"Negotiate": {creds, negotiateRequestEcho, ntlmRequest, negotiateExpect},
	}

	// execute test cases
	for _, p := range testAuthHeaders {
		server := p.MockServer(p.Creds, t)
		result := p.Request(server.URL, creds, t)
		server.Close()
		expect := p.Expect
		if result != expect {
			t.Errorf("Test failed. Result: '%s' / Expected:  '%s'", result, expect)
		}
	}
}

func ntlmRequestEcho(creds mockCreds, t *testing.T) *httptest.Server {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		reqAuthString := r.Header.Get("Authorization")
		if reqAuthString == "" {
			// go-ntlmssp first sends anonymous request, respond with 401
			w.Header().Add("WWW-Authenticate", "NTLM")
			w.WriteHeader(401)
		} else {
			w.Write([]byte(reqAuthString))
		}
	}))
	return server
}

func negotiateRequestEcho(creds mockCreds, t *testing.T) *httptest.Server {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		reqAuthString := r.Header.Get("Authorization")
		if reqAuthString == "" {
			// go-ntlmssp first sends anonymous request, respond with 401
			w.Header().Add("WWW-Authenticate", "Negotiate")
			w.WriteHeader(401)
		} else {
			w.Write([]byte(reqAuthString))
		}
	}))
	return server
}

func ntlmRequest(url string, creds mockCreds, t *testing.T) string {
	secretName := "ntlmTestAuthSecret"
	secretNamespace := "default"

	// ntlm clustersecretstore takes credentials from a secret,
	// so we need to mock k8s-client retrieval of secret.
	mockClient := fake.NewClientBuilder().WithObjects(&corev1.Secret{
		ObjectMeta: metav1.ObjectMeta{
			Namespace: secretNamespace,
			Name:      secretName,
			Labels: map[string]string{
				"external-secrets.io/type": "webhook",
			},
		},
		Data: map[string][]byte{
			"userName": []byte(creds.UserName),
			"password": []byte(creds.Password),
		},
	}).Build()

	// create clusteSecretStore
	ntlmAuthStore := &esv1.ClusterSecretStore{
		TypeMeta: metav1.TypeMeta{
			Kind: "ClusterSecretStore",
		},
		ObjectMeta: metav1.ObjectMeta{
			Name:      "webhook-store",
			Namespace: secretNamespace,
		},
		Spec: esv1.SecretStoreSpec{
			Provider: &esv1.SecretStoreProvider{
				Webhook: &esv1.WebhookProvider{
					URL: url,
					Auth: &esv1.AuthorizationProtocol{
						NTLM: &esv1.NTLMProtocol{
							UserName: esmeta.SecretKeySelector{
								Name:      secretName,
								Namespace: &secretNamespace,
								Key:       "userName",
							},
							Password: esmeta.SecretKeySelector{
								Name:      secretName,
								Namespace: &secretNamespace,
								Key:       "password",
							},
						},
					},
				},
			},
		},
	}

	result := exerciseGetSecret(ntlmAuthStore, mockClient, t)
	return result
}

func basicAuthRequestEcho(creds mockCreds, t *testing.T) *httptest.Server {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		reqAuthString := r.Header.Get("Authorization")
		if reqAuthString == "" {
			w.Write([]byte("Empty Authorization header"))
		} else {
			w.Write([]byte(reqAuthString))
		}
	}))

	return server
}

func basicAuthRequest(url string, creds mockCreds, t *testing.T) string {
	reqAuthString := "Basic " + b64.StdEncoding.EncodeToString([]byte(creds.UserName+":"+creds.Password))

	// create ClusterSecretStore
	basicAuthStore := &esv1.ClusterSecretStore{
		TypeMeta: metav1.TypeMeta{
			Kind: "ClusterSecretStore",
		},
		ObjectMeta: metav1.ObjectMeta{
			Name:      "webhook-store",
			Namespace: "default",
		},
		Spec: esv1.SecretStoreSpec{
			Provider: &esv1.SecretStoreProvider{
				Webhook: &esv1.WebhookProvider{
					URL: url,
					Headers: map[string]string{
						"Authorization": reqAuthString,
					},
				},
			},
		},
	}
	result := exerciseGetSecret(basicAuthStore, nil, t)
	return result
}

func exerciseGetSecret(mockStore esv1.GenericStore, mockKubeClient client.Client, t *testing.T) string {
	mockProvider := &Provider{}
	client, err := mockProvider.NewClient(context.Background(), mockStore, mockKubeClient, "default")
	if err != nil {
		t.Errorf("Error creating client: %q", err)
		return "error"
	}

	// perform request, exercising GetSecret
	resp, err := client.GetSecret(context.Background(), esv1.ExternalSecretDataRemoteRef{Key: "dummy"})
	if err != nil {
		t.Errorf("Error retrieving secret:%s", err)
	}
	return string(resp)
}