// Copyright 2020 the Pinniped contributors. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
package integration

import (
	"context"
	"io/ioutil"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"github.com/stretchr/testify/require"

	"go.pinniped.dev/test/library"
)

func TestCLI(t *testing.T) {
	library.SkipUnlessIntegration(t)
	library.SkipUnlessClusterHasCapability(t, library.ClusterSigningKeyIsAvailable)
	token := library.GetEnv(t, "PINNIPED_TEST_USER_TOKEN")
	namespaceName := library.GetEnv(t, "PINNIPED_NAMESPACE")
	testUsername := library.GetEnv(t, "PINNIPED_TEST_USER_USERNAME")
	expectedTestUserGroups := strings.Split(
		strings.ReplaceAll(library.GetEnv(t, "PINNIPED_TEST_USER_GROUPS"), " ", ""), ",",
	)

	// Remove all Pinniped environment variables for the remainder of this test
	// because some of their names clash with the env vars expected by our
	// kubectl exec plugin. We would like this test to prove that the exec
	// plugin receives all of the necessary env vars via the auto-generated
	// kubeconfig from the Pinniped CLI.
	initialEnvVars := make(map[string]string)
	for _, e := range os.Environ() {
		pair := strings.SplitN(e, "=", 2)
		name := pair[0]
		value := pair[1]
		if strings.HasPrefix(name, "PINNIPED_") {
			initialEnvVars[name] = value
			err := os.Unsetenv(name)
			require.NoError(t, err)
		}
	}
	// Put them back for other tests to use after this one
	t.Cleanup(func() {
		for k, v := range initialEnvVars {
			err := os.Setenv(k, v)
			require.NoError(t, err)
		}
	})

	// Build pinniped CLI.
	pinnipedExe, cleanupFunc := buildPinnipedCLI(t)
	defer cleanupFunc()

	// Run pinniped CLI to get kubeconfig.
	kubeConfig := runPinnipedCLI(t, pinnipedExe, token, namespaceName)

	// In addition to the client-go based testing below, also try the kubeconfig
	// with kubectl once just in case it is somehow different.
	runKubectlCLI(t, kubeConfig, namespaceName, testUsername)

	// Create Kubernetes client with kubeconfig from pinniped CLI.
	kubeClient := library.NewClientsetForKubeConfig(t, kubeConfig)

	// Validate that we can auth to the API via our user.
	ctx, cancelFunc := context.WithTimeout(context.Background(), time.Second*3)
	defer cancelFunc()

	adminClient := library.NewClientset(t)

	t.Run("access as user", accessAsUserTest(ctx, adminClient, testUsername, kubeClient))
	for _, group := range expectedTestUserGroups {
		group := group
		t.Run(
			"access as group "+group,
			accessAsGroupTest(ctx, adminClient, group, kubeClient),
		)
	}
}

func buildPinnipedCLI(t *testing.T) (string, func()) {
	t.Helper()

	pinnipedExeDir, err := ioutil.TempDir("", "pinniped-cli-test-*")
	require.NoError(t, err)

	pinnipedExe := filepath.Join(pinnipedExeDir, "pinniped")
	output, err := exec.Command(
		"go",
		"build",
		"-o",
		pinnipedExe,
		"go.pinniped.dev/cmd/pinniped",
	).CombinedOutput()
	require.NoError(t, err, string(output))

	return pinnipedExe, func() {
		require.NoError(t, os.RemoveAll(pinnipedExeDir))
	}
}

func runPinnipedCLI(t *testing.T, pinnipedExe, token, namespaceName string) string {
	t.Helper()

	output, err := exec.Command(
		pinnipedExe,
		"get-kubeconfig",
		"--token", token,
		"--pinniped-namespace", namespaceName,
	).CombinedOutput()
	require.NoError(t, err, string(output))

	return string(output)
}

func runKubectlCLI(t *testing.T, kubeConfig, namespaceName, username string) string {
	t.Helper()

	f, err := ioutil.TempFile("", "pinniped-generated-kubeconfig-*")
	require.NoError(t, err)
	defer func() {
		err := os.Remove(f.Name())
		require.NoError(t, err)
	}()
	_, err = f.WriteString(kubeConfig)
	require.NoError(t, err)
	err = f.Close()
	require.NoError(t, err)

	//nolint: gosec // It's okay that we are passing f.Name() to an exec command here. It was created above.
	output, err := exec.Command(
		"kubectl",
		"get",
		"pods",
		"--kubeconfig", f.Name(),
		"--namespace", namespaceName,
	).CombinedOutput()

	// Expect an error because this user has no RBAC permission. However, the
	// error message should state that we had already authenticated as the test user.
	expectedErrorMessage := `Error from server (Forbidden): pods is forbidden: User "` +
		username +
		`" cannot list resource "pods" in API group "" in the namespace "` +
		namespaceName +
		`"` + "\n"
	require.EqualError(t, err, "exit status 1")
	require.Equal(t, expectedErrorMessage, string(output))

	return string(output)
}