package server

import (
	"context"
	"os"
	"path/filepath"
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"github.com/netbirdio/netbird/client/internal/auth"
	"github.com/netbirdio/netbird/client/internal/localmetrics"
	"github.com/netbirdio/netbird/client/internal/profilemanager"
	"github.com/netbirdio/netbird/client/proto"
)

// These cover the RPC side of the cache: the cache itself is exercised in
// jwt_cache_test.go, but a correct cache buys nothing if the handlers around it
// consult the wrong identity or forget to clear it.

func TestCachedJWT_ServesTheOwner(t *testing.T) {
	s := newTestServer()
	owner := unprivilegedIdentity()
	s.jwtCache.store("token", owner, testTTL, s.jwtCache.currentGeneration())

	got, found := s.cachedJWT(ctxWithIdentity(owner))

	require.True(t, found, "the identity that obtained the token must get it back")
	assert.Equal(t, "token", got)
}

func TestCachedJWT_RefusesAnotherCaller(t *testing.T) {
	s := newTestServer()
	s.jwtCache.store("token", unprivilegedIdentity(), testTTL, s.jwtCache.currentGeneration())

	got, found := s.cachedJWT(ctxWithIdentity(privilegedIdentity()))

	assert.False(t, found, "a caller that did not obtain the token must get a miss")
	assert.Empty(t, got)
}

// A control channel that carries no caller identity — a TCP daemon socket, or a
// platform with no peer-credential primitive — cannot tell one local user from
// another, so cachedJWT must fail closed there.
func TestCachedJWT_WithoutCallerIdentity(t *testing.T) {
	s := newTestServer()
	s.jwtCache.store("token", unprivilegedIdentity(), testTTL, s.jwtCache.currentGeneration())

	got, found := s.cachedJWT(context.Background())

	assert.False(t, found)
	assert.Empty(t, got)
}

// profileFixture points the profile globals at a temp dir holding a single
// default profile, which is the one ActiveProfileState.FilePath resolves
// without consulting the current OS user.
func profileFixture(t *testing.T) string {
	t.Helper()

	dir := t.TempDir()
	defaultConfig := filepath.Join(dir, "default.json")
	require.NoError(t, os.WriteFile(defaultConfig, []byte("{}"), 0o600))

	origDir := profilemanager.DefaultConfigPathDir
	origDefault := profilemanager.DefaultConfigPath
	origState := profilemanager.ActiveProfileStatePath
	origOverride := profilemanager.ConfigDirOverride

	profilemanager.DefaultConfigPathDir = dir
	profilemanager.DefaultConfigPath = defaultConfig
	profilemanager.ActiveProfileStatePath = filepath.Join(dir, "active_profile.json")
	profilemanager.ConfigDirOverride = dir

	t.Cleanup(func() {
		profilemanager.DefaultConfigPathDir = origDir
		profilemanager.DefaultConfigPath = origDefault
		profilemanager.ActiveProfileStatePath = origState
		profilemanager.ConfigDirOverride = origOverride
	})

	return defaultConfig
}

// A profile carries its own NetBird account, so a token obtained under the
// previous one must not survive the switch even for the local user who
// obtained it.
func TestSwitchProfile_ClearsJWTCache(t *testing.T) {
	defaultConfig := profileFixture(t)

	// localmetrics.NewManager runs until its context is done, so the manager
	// must not outlive the test.
	ctx, cancel := context.WithCancel(context.Background())
	t.Cleanup(cancel)

	s := newTestServer()
	s.profileManager = profilemanager.NewServiceManager(defaultConfig)
	s.localMetrics = localmetrics.NewManager(ctx, s.statusRecorder, nil)

	// A second profile to move to, so the request goes through
	// switchProfileIfNeeded rather than the no-op path a nil request takes.
	const target = "second"
	username := "tester"
	_, err := profilemanager.UpdateOrCreateConfig(profilemanager.ConfigInput{
		ConfigPath:    filepath.Join(profilemanager.DefaultConfigPathDir, target+".json"),
		ManagementURL: "https://api.netbird.io:443",
	})
	require.NoError(t, err)

	owner := unprivilegedIdentity()
	s.jwtCache.store("token", owner, testTTL, s.jwtCache.currentGeneration())

	name := target
	_, err = s.SwitchProfile(ctx, &proto.SwitchProfileRequest{ProfileName: &name, Username: &username})
	require.NoError(t, err)

	active, err := s.profileManager.GetActiveProfileState()
	require.NoError(t, err)
	require.Equal(t, profilemanager.ID(target), active.ID, "the profile must actually have changed")

	_, found := s.jwtCache.get(owner)
	assert.False(t, found, "switching profile must drop the cached SSH JWT")
}

// Down ends the connection, not the session: the peer stays enrolled and the
// token still belongs to the same NetBird identity, so `down` followed by `up`
// must not cost the owner a fresh device-code flow.
//
// The logout handlers do call cleanupConnection, and SwitchProfile does not;
// what they have in common is that each clears the cache itself, right after,
// so tearing the connection down is no longer what decides the token's fate.
func TestCleanupConnection_KeepsJWTCache(t *testing.T) {
	s := newTestServer()
	_, cancel := context.WithCancel(context.Background())
	s.actCancel = cancel

	owner := unprivilegedIdentity()
	s.jwtCache.store("token", owner, testTTL, s.jwtCache.currentGeneration())

	require.NoError(t, s.cleanupConnection())

	got, found := s.jwtCache.get(owner)
	require.True(t, found, "going down must not drop the cached SSH JWT")
	assert.Equal(t, "token", got)
}

// fakeOAuthFlow stands in for the IdP round trip so a test can drive
// WaitJWTToken without a real device-code flow.
type fakeOAuthFlow struct {
	token string
}

func (f *fakeOAuthFlow) RequestAuthInfo(context.Context) (auth.AuthFlowInfo, error) {
	return auth.AuthFlowInfo{DeviceCode: "device-code"}, nil
}

func (f *fakeOAuthFlow) WaitToken(context.Context, auth.AuthFlowInfo) (auth.TokenInfo, error) {
	return auth.TokenInfo{AccessToken: f.token}, nil
}

func (f *fakeOAuthFlow) GetClientID(context.Context) string { return "client-id" }

// The flow outlives a profile switch, because SwitchProfile does not reset
// s.oauthAuthFlow. A switch between RequestJWTAuth and the IdP answering must
// still keep the token out of the cache the new profile uses, and the
// generation the flow carries is what decides it: reading the cache's own
// generation at store time would already be the new one.
func TestWaitJWTToken_DropsTokenFromASessionThatEndedBeforeTheWait(t *testing.T) {
	s := newTestServer()
	owner := unprivilegedIdentity()
	ttl := int(testTTL.Seconds())
	s.config = &profilemanager.Config{SSHJWTCacheTTL: &ttl}

	// RequestJWTAuth ran under the previous session and recorded its generation.
	s.oauthAuthFlow.flow = &fakeOAuthFlow{token: "token-from-the-old-session"}
	s.oauthAuthFlow.info = auth.AuthFlowInfo{DeviceCode: "device-code"}
	s.oauthAuthFlow.cacheGeneration = s.jwtCache.currentGeneration()

	// A profile switch or a logout lands before the caller reaches WaitJWTToken.
	s.jwtCache.clear()

	_, err := s.WaitJWTToken(ctxWithIdentity(owner), &proto.WaitJWTTokenRequest{DeviceCode: "device-code"})
	require.NoError(t, err)

	_, found := s.jwtCache.get(owner)
	assert.False(t, found, "a token whose flow started under the previous session must not be cached")
}