/*
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 exec_test // separate package to prevent circular import

import (
	"context"
	"testing"
	"time"

	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	utilnet "k8s.io/apimachinery/pkg/util/net"
	clientset "k8s.io/client-go/kubernetes"
	"k8s.io/client-go/rest"
	clientcmdapi "k8s.io/client-go/tools/clientcmd/api"
)

// TestExecTLSCache asserts the semantics of the TLS cache when exec auth is used.
//
// In particular, when:
//   - multiple identical rest configs exist as distinct objects, and
//   - these rest configs use exec auth, and
//   - these rest configs are used to create distinct clientsets, then
//
// the underlying TLS config is shared between those clientsets.
func TestExecTLSCache(t *testing.T) {
	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
	t.Cleanup(cancel)

	config1 := &rest.Config{
		Host: "https://localhost",
		ExecProvider: &clientcmdapi.ExecConfig{
			Command:         "./testdata/test-plugin.sh",
			APIVersion:      "client.authentication.k8s.io/v1",
			InteractiveMode: clientcmdapi.IfAvailableExecInteractiveMode,
		},
	}
	client1 := clientset.NewForConfigOrDie(config1)

	config2 := &rest.Config{
		Host: "https://localhost",
		ExecProvider: &clientcmdapi.ExecConfig{
			Command:         "./testdata/test-plugin.sh",
			APIVersion:      "client.authentication.k8s.io/v1",
			InteractiveMode: clientcmdapi.IfAvailableExecInteractiveMode,
		},
	}
	client2 := clientset.NewForConfigOrDie(config2)

	config3 := &rest.Config{
		Host: "https://localhost",
		ExecProvider: &clientcmdapi.ExecConfig{
			Command:         "./testdata/test-plugin.sh",
			Args:            []string{"make this exec auth different"},
			APIVersion:      "client.authentication.k8s.io/v1",
			InteractiveMode: clientcmdapi.IfAvailableExecInteractiveMode,
		},
	}
	client3 := clientset.NewForConfigOrDie(config3)

	_, _ = client1.CoreV1().Nodes().List(ctx, metav1.ListOptions{})
	_, _ = client2.CoreV1().Namespaces().List(ctx, metav1.ListOptions{})
	_, _ = client3.CoreV1().PersistentVolumes().List(ctx, metav1.ListOptions{})

	rt1 := client1.RESTClient().(*rest.RESTClient).Client.Transport
	rt2 := client2.RESTClient().(*rest.RESTClient).Client.Transport
	rt3 := client3.RESTClient().(*rest.RESTClient).Client.Transport

	tlsConfig1, err := utilnet.TLSClientConfig(rt1)
	if err != nil {
		t.Fatal(err)
	}
	tlsConfig2, err := utilnet.TLSClientConfig(rt2)
	if err != nil {
		t.Fatal(err)
	}
	tlsConfig3, err := utilnet.TLSClientConfig(rt3)
	if err != nil {
		t.Fatal(err)
	}

	if tlsConfig1 == nil || tlsConfig2 == nil || tlsConfig3 == nil {
		t.Fatal("expected non-nil TLS configs")
	}

	if tlsConfig1 != tlsConfig2 {
		t.Fatal("expected the same TLS config for matching exec config via rest config")
	}

	if tlsConfig1 == tlsConfig3 {
		t.Fatal("expected different TLS config for non-matching exec config via rest config")
	}
}