fix: resolve bugs found in pre-release review

internal/deezer/client.go

@@ -213,6 +213,7 @@ func (c *Client) MediaStream(ctx context.Context, media *Media) (io.ReadCloser,
 	}
 
 	if resp.StatusCode != http.StatusOK {
+		resp.Body.Close()
 		return nil, fmt.Errorf("unexpected status code: %d", resp.StatusCode)
 	}
 

internal/deezer/gateway.go

@@ -120,6 +120,10 @@ func (m *mobileClient) authenticate(ctx context.Context) (string, string, string
 		return "", "", "", err
 	}
 
+	if len(decrypted) < 96 {
+		return "", "", "", fmt.Errorf("unexpected response from gateway")
+	}
+
 	token := string(decrypted[0:64])
 	tokenKey := string(decrypted[64:80])
 	userKey := string(decrypted[80:96])

internal/deezer/login.go

@@ -2,6 +2,7 @@ package deezer
 
 import (
 	"context"
+	"errors"
 	"fmt"
 )
 
@@ -12,9 +13,14 @@ func resolveARL(ctx context.Context, validate func(ctx context.Context, arl stri
 	}
 
 	if creds != nil && creds.ARL != "" {
-		if verr := validate(ctx, creds.ARL); verr == nil {
+		verr := validate(ctx, creds.ARL)
+		if verr == nil {
 			return creds.ARL, nil
 		}
+
+		if !errors.Is(verr, ErrInvalidARL) {
+			return "", fmt.Errorf("stored session could not be validated: %w", verr)
+		}
 	}
 
 	if creds != nil && creds.Email != "" && creds.Password != "" {

internal/deezer/session.go

@@ -3,6 +3,7 @@ package deezer
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -10,6 +11,8 @@ import (
 	"time"
 )
 
+var ErrInvalidARL = errors.New("invalid or expired ARL cookie")
+
 type Session struct {
 	APIToken     string
 	LicenseToken string
@@ -71,7 +74,7 @@ func authenticate(ctx context.Context, arlCookie string) (*Session, error) {
 	}
 
 	if res.Results.User.ID == 0 {
-		return nil, fmt.Errorf("invalid or expired ARL cookie")
+		return nil, ErrInvalidARL
 	}
 
 	opts := res.Results.User.Options

internal/deezer/track.go

@@ -62,7 +62,27 @@ func (t *Track) Filename(kind Kind, mediaFormat string) string {
 		}
 	}
 
-	fileName := fmt.Sprintf("%s%s - %s.%s", prefix, t.Artist, t.FullTitle(), ext)
-	fileName, _ = filenamify.Filenamify(fileName, filenamify.Options{MaxLength: 255})
-	return fileName
+	base := fmt.Sprintf("%s%s - %s", prefix, t.Artist, t.FullTitle())
+	base, _ = filenamify.Filenamify(base, filenamify.Options{MaxLength: 255})
+	base = truncateBytes(base, 255-len(ext)-1-len("-id3v2"))
+
+	return base + "." + ext
+}
+
+func truncateBytes(s string, max int) string {
+	if max <= 0 {
+		return ""
+	}
+	if len(s) <= max {
+		return s
+	}
+
+	last := 0
+	for i := range s {
+		if i > max {
+			return s[:last]
+		}
+		last = i
+	}
+	return s[:last]
 }