Fix token refresh

vehicle/mercedes/identity.go

@@ -30,8 +30,8 @@ type Identity struct {
 	log *util.Logger
 	*ReuseTokenSource
 	sessionSecret []byte
-	authC         chan<- bool
 	oc            *oauth2.Config
+	authC         chan<- bool
 }
 
 func generateSecret() ([]byte, error) {
@@ -47,17 +47,25 @@ func NewIdentity(log *util.Logger, id, secret string, options ...IdentityOptions
 		return nil, fmt.Errorf("failed to initialize OIDC provider: %s", err)
 	}
 
-	v := &Identity{
-		log: log,
-		oc: &oauth2.Config{
-			ClientID:     id,
-			ClientSecret: secret,
-			Endpoint:     provider.Endpoint(),
-			Scopes:       []string{oidc.ScopeOfflineAccess, "mb:vehicle:mbdata:evstatus"},
-		},
+	oc := &oauth2.Config{
+		ClientID:     id,
+		ClientSecret: secret,
+		Endpoint:     provider.Endpoint(),
+		Scopes:       []string{oidc.ScopeOfflineAccess, "mb:vehicle:mbdata:evstatus"},
 	}
 
-	v.ReuseTokenSource = &ReuseTokenSource{cb: v.invalidToken}
+	v := &Identity{
+		log: log,
+		oc:  oc,
+	}
+
+	ts := &ReuseTokenSource{
+		oc: oc,
+		cb: v.invalidToken,
+	}
+	ts.Apply(nil)
+
+	v.ReuseTokenSource = ts
 	v.sessionSecret, err = generateSecret()
 
 	for _, o := range options {

vehicle/mercedes/tokensource.go

@@ -1,17 +1,16 @@
 package mercedes
 
 import (
-	"fmt"
+	"context"
 	"sync"
 
 	"golang.org/x/oauth2"
 )
 
-var ErrNotLoggedIn = fmt.Errorf("not logged in")
-
 type ReuseTokenSource struct {
 	mu sync.Mutex
-	t  *oauth2.Token
+	oc *oauth2.Config
+	ts oauth2.TokenSource
 	cb func()
 }
 
@@ -19,17 +18,17 @@ func (ts *ReuseTokenSource) Token() (*oauth2.Token, error) {
 	ts.mu.Lock()
 	defer ts.mu.Unlock()
 
-	if ts.t.Valid() {
-		return ts.t, nil
+	t, err := ts.ts.Token()
+	if err != nil || !t.Valid() {
+		// invalid token callback
+		ts.cb()
 	}
 
-	ts.cb() // invalid token callback
-
-	return nil, ErrNotLoggedIn
+	return t, err
 }
 
 func (ts *ReuseTokenSource) Apply(t *oauth2.Token) {
 	ts.mu.Lock()
-	ts.t = t
+	ts.ts = ts.oc.TokenSource(context.Background(), t)
 	ts.mu.Unlock()
 }