package cmd

import (
	"bytes"
	"context"
	"encoding/base64"
	"encoding/json"
	"errors"
	"net"
	"strconv"
	"strings"
	"testing"
	"time"

	"github.com/edgelesssys/constellation/bootstrapper/initproto"
	"github.com/edgelesssys/constellation/cli/internal/cloudcmd"
	"github.com/edgelesssys/constellation/internal/attestation/vtpm"
	"github.com/edgelesssys/constellation/internal/cloud/cloudprovider"
	"github.com/edgelesssys/constellation/internal/cloud/cloudtypes"
	"github.com/edgelesssys/constellation/internal/config"
	"github.com/edgelesssys/constellation/internal/constants"
	"github.com/edgelesssys/constellation/internal/file"
	"github.com/edgelesssys/constellation/internal/grpc/atlscredentials"
	"github.com/edgelesssys/constellation/internal/grpc/dialer"
	"github.com/edgelesssys/constellation/internal/grpc/testdialer"
	"github.com/edgelesssys/constellation/internal/license"
	"github.com/edgelesssys/constellation/internal/oid"
	"github.com/edgelesssys/constellation/internal/state"
	"github.com/spf13/afero"
	"github.com/spf13/cobra"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"google.golang.org/grpc"
)

func TestInitArgumentValidation(t *testing.T) {
	assert := assert.New(t)

	cmd := NewInitCmd()
	assert.NoError(cmd.ValidateArgs(nil))
	assert.Error(cmd.ValidateArgs([]string{"something"}))
	assert.Error(cmd.ValidateArgs([]string{"sth", "sth"}))
}

func TestInitialize(t *testing.T) {
	testGcpState := state.ConstellationState{
		CloudProvider:    "GCP",
		BootstrapperHost: "192.0.2.1",
		GCPWorkerInstances: cloudtypes.Instances{
			"id-0": {PrivateIP: "192.0.2.1", PublicIP: "192.0.2.1"},
			"id-1": {PrivateIP: "192.0.2.1", PublicIP: "192.0.2.1"},
		},
		GCPControlPlaneInstances: cloudtypes.Instances{
			"id-c": {PrivateIP: "192.0.2.1", PublicIP: "192.0.2.1"},
		},
	}
	testAzureState := state.ConstellationState{
		CloudProvider:    "Azure",
		BootstrapperHost: "192.0.2.1",
		AzureWorkerInstances: cloudtypes.Instances{
			"id-0": {PrivateIP: "192.0.2.1", PublicIP: "192.0.2.1"},
			"id-1": {PrivateIP: "192.0.2.1", PublicIP: "192.0.2.1"},
		},
		AzureControlPlaneInstances: cloudtypes.Instances{
			"id-c": {PrivateIP: "192.0.2.1", PublicIP: "192.0.2.1"},
		},
		AzureResourceGroup: "test",
	}
	testQemuState := state.ConstellationState{
		CloudProvider:    "QEMU",
		BootstrapperHost: "192.0.2.1",
		QEMUWorkerInstances: cloudtypes.Instances{
			"id-0": {PrivateIP: "192.0.2.1", PublicIP: "192.0.2.1"},
			"id-1": {PrivateIP: "192.0.2.1", PublicIP: "192.0.2.1"},
		},
		QEMUControlPlaneInstances: cloudtypes.Instances{
			"id-c": {PrivateIP: "192.0.2.1", PublicIP: "192.0.2.1"},
		},
	}
	testInitResp := &initproto.InitResponse{
		Kubeconfig: []byte("kubeconfig"),
		OwnerId:    []byte("ownerID"),
		ClusterId:  []byte("clusterID"),
	}
	someErr := errors.New("failed")

	testCases := map[string]struct {
		existingState         state.ConstellationState
		serviceAccountCreator stubServiceAccountCreator
		helmLoader            stubHelmLoader
		initServerAPI         *stubInitServer
		setAutoscaleFlag      bool
		wantErr               bool
	}{
		"initialize some gcp instances": {
			existingState: testGcpState,
			initServerAPI: &stubInitServer{initResp: testInitResp},
		},
		"initialize some azure instances": {
			existingState: testAzureState,
			initServerAPI: &stubInitServer{initResp: testInitResp},
		},
		"initialize some qemu instances": {
			existingState: testQemuState,
			initServerAPI: &stubInitServer{initResp: testInitResp},
		},
		"initialize gcp with autoscaling": {
			existingState:    testGcpState,
			initServerAPI:    &stubInitServer{initResp: testInitResp},
			setAutoscaleFlag: true,
		},
		"initialize azure with autoscaling": {
			existingState:    testAzureState,
			initServerAPI:    &stubInitServer{initResp: testInitResp},
			setAutoscaleFlag: true,
		},
		"empty state": {
			existingState: state.ConstellationState{},
			initServerAPI: &stubInitServer{},
			wantErr:       true,
		},
		"init call fails": {
			existingState: testGcpState,
			initServerAPI: &stubInitServer{initErr: someErr},
			wantErr:       true,
		},
		"fail to create service account": {
			existingState:         testGcpState,
			initServerAPI:         &stubInitServer{},
			serviceAccountCreator: stubServiceAccountCreator{createErr: someErr},
			wantErr:               true,
		},
		"fail to load helm charts": {
			existingState: testGcpState,
			helmLoader:    stubHelmLoader{loadErr: someErr},
			initServerAPI: &stubInitServer{initResp: testInitResp},
			wantErr:       true,
		},
	}

	for name, tc := range testCases {
		t.Run(name, func(t *testing.T) {
			assert := assert.New(t)
			require := require.New(t)

			netDialer := testdialer.NewBufconnDialer()
			newDialer := func(*cloudcmd.Validator) *dialer.Dialer {
				return dialer.New(nil, nil, netDialer)
			}
			serverCreds := atlscredentials.New(nil, nil)
			initServer := grpc.NewServer(grpc.Creds(serverCreds))
			initproto.RegisterAPIServer(initServer, tc.initServerAPI)
			port := strconv.Itoa(constants.BootstrapperPort)
			listener := netDialer.GetListener(net.JoinHostPort("192.0.2.1", port))
			go initServer.Serve(listener)
			defer initServer.GracefulStop()

			cmd := NewInitCmd()
			var out bytes.Buffer
			cmd.SetOut(&out)
			var errOut bytes.Buffer
			cmd.SetErr(&errOut)
			cmd.Flags().String("config", constants.ConfigFilename, "") // register persistent flag manually
			fs := afero.NewMemMapFs()
			fileHandler := file.NewHandler(fs)

			config := defaultConfigWithExpectedMeasurements(t, cloudprovider.FromString(tc.existingState.CloudProvider))
			require.NoError(fileHandler.WriteYAML(constants.ConfigFilename, config))
			require.NoError(fileHandler.WriteJSON(constants.StateFilename, tc.existingState, file.OptNone))
			require.NoError(cmd.Flags().Set("autoscale", strconv.FormatBool(tc.setAutoscaleFlag)))

			ctx := context.Background()
			ctx, cancel := context.WithTimeout(ctx, 4*time.Second)
			defer cancel()
			cmd.SetContext(ctx)

			err := initialize(cmd, newDialer, &tc.serviceAccountCreator, fileHandler, &tc.helmLoader, &stubLicenseClient{})

			if tc.wantErr {
				assert.Error(err)
				return
			}
			require.NoError(err)
			// assert.Contains(out.String(), base64.StdEncoding.EncodeToString([]byte("ownerID")))
			assert.Contains(out.String(), base64.StdEncoding.EncodeToString([]byte("clusterID")))
			if tc.setAutoscaleFlag {
				assert.Len(tc.initServerAPI.activateAutoscalingNodeGroups, 1)
			} else {
				assert.Len(tc.initServerAPI.activateAutoscalingNodeGroups, 0)
			}
		})
	}
}

func TestWriteOutput(t *testing.T) {
	assert := assert.New(t)

	resp := &initproto.InitResponse{
		OwnerId:    []byte("ownerID"),
		ClusterId:  []byte("clusterID"),
		Kubeconfig: []byte("kubeconfig"),
	}

	ownerID := base64.StdEncoding.EncodeToString(resp.OwnerId)
	clusterID := base64.StdEncoding.EncodeToString(resp.ClusterId)

	expectedIDFile := clusterIDsFile{
		ClusterID: clusterID,
		OwnerID:   ownerID,
		IP:        "cluster-ip",
	}

	var out bytes.Buffer
	testFs := afero.NewMemMapFs()
	fileHandler := file.NewHandler(testFs)

	err := writeOutput(resp, "cluster-ip", &out, fileHandler)
	assert.NoError(err)
	// assert.Contains(out.String(), ownerID)
	assert.Contains(out.String(), clusterID)
	assert.Contains(out.String(), constants.AdminConfFilename)

	afs := afero.Afero{Fs: testFs}
	adminConf, err := afs.ReadFile(constants.AdminConfFilename)
	assert.NoError(err)
	assert.Equal(string(resp.Kubeconfig), string(adminConf))

	idsFile, err := afs.ReadFile(constants.ClusterIDsFileName)
	assert.NoError(err)
	var testIDFile clusterIDsFile
	err = json.Unmarshal(idsFile, &testIDFile)
	assert.NoError(err)
	assert.Equal(expectedIDFile, testIDFile)
}

func TestInitCompletion(t *testing.T) {
	testCases := map[string]struct {
		args        []string
		toComplete  string
		wantResult  []string
		wantShellCD cobra.ShellCompDirective
	}{
		"first arg": {
			args:        []string{},
			toComplete:  "hello",
			wantResult:  []string{},
			wantShellCD: cobra.ShellCompDirectiveDefault,
		},
		"secnod arg": {
			args:        []string{"23"},
			toComplete:  "/test/h",
			wantResult:  []string{},
			wantShellCD: cobra.ShellCompDirectiveError,
		},
		"third arg": {
			args:        []string{"./file", "sth"},
			toComplete:  "./file",
			wantResult:  []string{},
			wantShellCD: cobra.ShellCompDirectiveError,
		},
	}

	for name, tc := range testCases {
		t.Run(name, func(t *testing.T) {
			assert := assert.New(t)

			cmd := &cobra.Command{}
			result, shellCD := initCompletion(cmd, tc.args, tc.toComplete)
			assert.Equal(tc.wantResult, result)
			assert.Equal(tc.wantShellCD, shellCD)
		})
	}
}

func TestReadOrGeneratedMasterSecret(t *testing.T) {
	testCases := map[string]struct {
		filename       string
		createFileFunc func(handler file.Handler) error
		fs             func() afero.Fs
		wantErr        bool
	}{
		"file with secret exists": {
			filename: "someSecret",
			fs:       afero.NewMemMapFs,
			createFileFunc: func(handler file.Handler) error {
				return handler.WriteJSON(
					"someSecret",
					masterSecret{Key: []byte("constellation-master-secret"), Salt: []byte("constellation-32Byte-length-salt")},
					file.OptNone,
				)
			},
			wantErr: false,
		},
		"no file given": {
			filename:       "",
			createFileFunc: func(handler file.Handler) error { return nil },
			fs:             afero.NewMemMapFs,
			wantErr:        false,
		},
		"file does not exist": {
			filename:       "nonExistingSecret",
			createFileFunc: func(handler file.Handler) error { return nil },
			fs:             afero.NewMemMapFs,
			wantErr:        true,
		},
		"file is empty": {
			filename: "emptySecret",
			createFileFunc: func(handler file.Handler) error {
				return handler.Write("emptySecret", []byte{}, file.OptNone)
			},
			fs:      afero.NewMemMapFs,
			wantErr: true,
		},
		"salt too short": {
			filename: "shortSecret",
			createFileFunc: func(handler file.Handler) error {
				return handler.WriteJSON(
					"shortSecret",
					masterSecret{Key: []byte("constellation-master-secret"), Salt: []byte("short")},
					file.OptNone,
				)
			},
			fs:      afero.NewMemMapFs,
			wantErr: true,
		},
		"key too short": {
			filename: "shortSecret",
			createFileFunc: func(handler file.Handler) error {
				return handler.WriteJSON(
					"shortSecret",
					masterSecret{Key: []byte("short"), Salt: []byte("constellation-32Byte-length-salt")},
					file.OptNone,
				)
			},
			fs:      afero.NewMemMapFs,
			wantErr: true,
		},
		"invalid file content": {
			filename: "unencodedSecret",
			createFileFunc: func(handler file.Handler) error {
				return handler.Write("unencodedSecret", []byte("invalid-constellation-master-secret"), file.OptNone)
			},
			fs:      afero.NewMemMapFs,
			wantErr: true,
		},
		"file not writeable": {
			filename:       "",
			createFileFunc: func(handler file.Handler) error { return nil },
			fs:             func() afero.Fs { return afero.NewReadOnlyFs(afero.NewMemMapFs()) },
			wantErr:        true,
		},
	}

	for name, tc := range testCases {
		t.Run(name, func(t *testing.T) {
			assert := assert.New(t)
			require := require.New(t)

			fileHandler := file.NewHandler(tc.fs())
			require.NoError(tc.createFileFunc(fileHandler))

			var out bytes.Buffer
			secret, err := readOrGenerateMasterSecret(&out, fileHandler, tc.filename)

			if tc.wantErr {
				assert.Error(err)
			} else {
				assert.NoError(err)

				if tc.filename == "" {
					require.Contains(out.String(), constants.MasterSecretFilename)
					filename := strings.Split(out.String(), "./")
					tc.filename = strings.Trim(filename[1], "\n")
				}

				var masterSecret masterSecret
				require.NoError(fileHandler.ReadJSON(tc.filename, &masterSecret))
				assert.Equal(masterSecret.Key, secret.Key)
				assert.Equal(masterSecret.Salt, secret.Salt)
			}
		})
	}
}

func TestAttestation(t *testing.T) {
	assert := assert.New(t)
	require := require.New(t)

	initServerAPI := &stubInitServer{initResp: &initproto.InitResponse{
		Kubeconfig: []byte("kubeconfig"),
		OwnerId:    []byte("ownerID"),
		ClusterId:  []byte("clusterID"),
	}}
	existingState := state.ConstellationState{
		CloudProvider:    "QEMU",
		BootstrapperHost: "192.0.2.1",
		QEMUWorkerInstances: cloudtypes.Instances{
			"id-0": {PrivateIP: "192.0.2.1", PublicIP: "192.0.2.1"},
			"id-1": {PrivateIP: "192.0.2.1", PublicIP: "192.0.2.1"},
		},
		QEMUControlPlaneInstances: cloudtypes.Instances{
			"id-c": {PrivateIP: "192.0.2.1", PublicIP: "192.0.2.1"},
		},
	}

	netDialer := testdialer.NewBufconnDialer()
	newDialer := func(v *cloudcmd.Validator) *dialer.Dialer {
		validator := &testValidator{
			Getter: oid.QEMU{},
			pcrs:   v.PCRS(),
		}
		return dialer.New(nil, validator, netDialer)
	}

	issuer := &testIssuer{
		Getter: oid.QEMU{},
		pcrs: map[uint32][]byte{
			0: []byte("ffffffffffffffffffffffffffffffff"),
			1: []byte("ffffffffffffffffffffffffffffffff"),
			2: []byte("ffffffffffffffffffffffffffffffff"),
			3: []byte("ffffffffffffffffffffffffffffffff"),
		},
	}
	serverCreds := atlscredentials.New(issuer, nil)
	initServer := grpc.NewServer(grpc.Creds(serverCreds))
	initproto.RegisterAPIServer(initServer, initServerAPI)
	port := strconv.Itoa(constants.BootstrapperPort)
	listener := netDialer.GetListener(net.JoinHostPort("192.0.2.1", port))
	go initServer.Serve(listener)
	defer initServer.GracefulStop()

	cmd := NewInitCmd()
	cmd.Flags().String("config", constants.ConfigFilename, "") // register persistent flag manually
	var out bytes.Buffer
	cmd.SetOut(&out)
	var errOut bytes.Buffer
	cmd.SetErr(&errOut)

	fs := afero.NewMemMapFs()
	fileHandler := file.NewHandler(fs)
	require.NoError(fileHandler.WriteJSON(constants.StateFilename, existingState, file.OptNone))

	cfg := config.Default()
	cfg.RemoveProviderExcept(cloudprovider.QEMU)
	cfg.Provider.QEMU.Measurements[0] = []byte("00000000000000000000000000000000")
	cfg.Provider.QEMU.Measurements[1] = []byte("11111111111111111111111111111111")
	cfg.Provider.QEMU.Measurements[2] = []byte("22222222222222222222222222222222")
	cfg.Provider.QEMU.Measurements[3] = []byte("33333333333333333333333333333333")
	require.NoError(fileHandler.WriteYAML(constants.ConfigFilename, cfg, file.OptNone))

	ctx := context.Background()
	ctx, cancel := context.WithTimeout(ctx, 4*time.Second)
	defer cancel()
	cmd.SetContext(ctx)

	err := initialize(cmd, newDialer, &stubServiceAccountCreator{}, fileHandler, &stubHelmLoader{}, &stubLicenseClient{})
	assert.Error(err)
	// make sure the error is actually a TLS handshake error
	assert.Contains(err.Error(), "transport: authentication handshake failed")
}

type testValidator struct {
	oid.Getter
	pcrs map[uint32][]byte
}

func (v *testValidator) Validate(attDoc []byte, nonce []byte) ([]byte, error) {
	var attestation struct {
		UserData []byte
		PCRs     map[uint32][]byte
	}
	if err := json.Unmarshal(attDoc, &attestation); err != nil {
		return nil, err
	}

	for k, pcr := range v.pcrs {
		if !bytes.Equal(attestation.PCRs[k], pcr) {
			return nil, errors.New("invalid PCR value")
		}
	}
	return attestation.UserData, nil
}

func (v *testValidator) AddLogger(vtpm.WarnLogger) {}

type testIssuer struct {
	oid.Getter
	pcrs map[uint32][]byte
}

func (i *testIssuer) Issue(userData []byte, nonce []byte) ([]byte, error) {
	return json.Marshal(
		struct {
			UserData []byte
			PCRs     map[uint32][]byte
		}{
			UserData: userData,
			PCRs:     i.pcrs,
		},
	)
}

type stubInitServer struct {
	initResp *initproto.InitResponse
	initErr  error

	activateAutoscalingNodeGroups []string

	initproto.UnimplementedAPIServer
}

func (s *stubInitServer) Init(ctx context.Context, req *initproto.InitRequest) (*initproto.InitResponse, error) {
	s.activateAutoscalingNodeGroups = req.AutoscalingNodeGroups
	return s.initResp, s.initErr
}

func defaultConfigWithExpectedMeasurements(t *testing.T, csp cloudprovider.Provider) *config.Config {
	t.Helper()
	config := config.Default()

	config.Provider.Azure.SubscriptionID = "01234567-0123-0123-0123-0123456789ab"
	config.Provider.Azure.TenantID = "01234567-0123-0123-0123-0123456789ab"
	config.Provider.Azure.Location = "test-location"
	config.Provider.Azure.UserAssignedIdentity = "test-identity"
	config.Provider.Azure.Measurements[8] = []byte("00000000000000000000000000000000")
	config.Provider.Azure.Measurements[9] = []byte("11111111111111111111111111111111")

	config.Provider.GCP.Region = "test-region"
	config.Provider.GCP.Project = "test-project"
	config.Provider.GCP.Zone = "test-zone"
	config.Provider.GCP.Measurements[8] = []byte("00000000000000000000000000000000")
	config.Provider.GCP.Measurements[9] = []byte("11111111111111111111111111111111")

	config.Provider.QEMU.Measurements[8] = []byte("00000000000000000000000000000000")
	config.Provider.QEMU.Measurements[9] = []byte("11111111111111111111111111111111")

	config.RemoveProviderExcept(csp)
	return config
}

type stubLicenseClient struct{}

func (c *stubLicenseClient) CheckQuota(ctx context.Context, checkRequest license.CheckQuotaRequest) (license.CheckQuotaResponse, error) {
	return license.CheckQuotaResponse{
		Quota: license.CommunityQuota,
	}, nil
}