harden deezer quality fallback and metadata handling

Improve Deezer full-quality mode behavior by returning explicit errors when yt-dlp mode fails with fallback disabled, parse structured API errors, and correctly map explicit_lyrics booleans into explicit tags.

internal/provider/deezer/client.go

@@ -175,7 +175,7 @@ func (c *Client) GetDownloadable(ctx context.Context, item string, _ int) (*prov
 			return d, nil
 		}
 		if !c.cfg.Session.Deezer.LowerQualityIfNotAvailable {
-			return nil, dlErr
+			return nil, fmt.Errorf("deezer full-quality mode failed and fallback is disabled: %w", dlErr)
 		}
 	}
 	preview := strings.TrimSpace(stringFromAny(meta["preview"]))
@@ -352,8 +352,15 @@ func (c *Client) apiGet(ctx context.Context, path string, params url.Values) (ma
 	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
 		return nil, fmt.Errorf("deezer api failed: status=%d body=%s", resp.StatusCode, string(body))
 	}
-	if e := stringFromAny(out["error"]); e != "" {
-		return nil, fmt.Errorf("deezer api error: %s", e)
+	if errObj, ok := out["error"].(map[string]any); ok {
+		msg := strings.TrimSpace(stringFromAny(errObj["message"]))
+		if msg == "" {
+			msg = strings.TrimSpace(stringFromAny(errObj["type"]))
+		}
+		if msg == "" {
+			msg = "unknown deezer error"
+		}
+		return nil, fmt.Errorf("deezer api error: %s", msg)
 	}
 	return out, nil
 }
@@ -375,7 +382,7 @@ func enrichTrack(track map[string]any) {
 			track["media_number"] = d
 		}
 	}
-	if v := stringFromAny(track["explicit_lyrics"]); v == "true" {
+	if boolFromAny(track["explicit_lyrics"]) {
 		track["explicit"] = true
 	}
 }
@@ -441,6 +448,11 @@ func intFromAny(v any) int {
 	}
 }
 
+func boolFromAny(v any) bool {
+	b, ok := v.(bool)
+	return ok && b
+}
+
 func runCommand(ctx context.Context, name string, args ...string) ([]byte, error) {
 	cmd := exec.CommandContext(ctx, name, args...)
 	b, err := cmd.CombinedOutput()

internal/provider/deezer/client_test.go

@@ -3,8 +3,10 @@ package deezer
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 	"net/http"
 	"net/http/httptest"
+	"strings"
 	"testing"
 
 	"streamrip-go/internal/config"
@@ -64,3 +66,87 @@ func TestGetDownloadableUsesPreview(t *testing.T) {
 		t.Fatalf("unexpected downloadable: %+v", d)
 	}
 }
+
+func TestGetMetadataSetsExplicitFromBool(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		switch r.URL.Path {
+		case "/track/9":
+			_ = json.NewEncoder(w).Encode(map[string]any{
+				"id":              9,
+				"title":           "X",
+				"explicit_lyrics": true,
+				"artist":          map[string]any{"name": "Artist"},
+			})
+		default:
+			w.WriteHeader(http.StatusNotFound)
+		}
+	}))
+	defer ts.Close()
+
+	cfgData := config.DefaultConfigData()
+	c := New(&config.Config{File: cfgData, Session: cfgData})
+	c.loggedIn = true
+	orig := baseURL
+	baseURL = ts.URL
+	defer func() { baseURL = orig }()
+
+	meta, err := c.GetMetadata(context.Background(), "9", "track")
+	if err != nil {
+		t.Fatalf("GetMetadata() error = %v", err)
+	}
+	if explicit, _ := meta["explicit"].(bool); !explicit {
+		t.Fatalf("expected explicit=true, got %#v", meta["explicit"])
+	}
+}
+
+func TestSearchReturnsStructuredAPIError(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path == "/search/track" {
+			_ = json.NewEncoder(w).Encode(map[string]any{"error": map[string]any{"message": "invalid query"}})
+			return
+		}
+		w.WriteHeader(http.StatusNotFound)
+	}))
+	defer ts.Close()
+
+	cfgData := config.DefaultConfigData()
+	c := New(&config.Config{File: cfgData, Session: cfgData})
+	c.loggedIn = true
+	orig := baseURL
+	baseURL = ts.URL
+	defer func() { baseURL = orig }()
+
+	_, err := c.Search(context.Background(), "track", "", 5)
+	if err == nil || !strings.Contains(err.Error(), "invalid query") {
+		t.Fatalf("expected structured deezer error, got %v", err)
+	}
+}
+
+func TestGetDownloadableErrorsWhenFullQualityFailsAndFallbackDisabled(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path == "/track/42" {
+			_ = json.NewEncoder(w).Encode(map[string]any{"id": 42, "title": "X", "preview": "https://cdn.example/p.mp3"})
+			return
+		}
+		w.WriteHeader(http.StatusNotFound)
+	}))
+	defer ts.Close()
+
+	cfgData := config.DefaultConfigData()
+	cfgData.Deezer.UseDeezloader = true
+	cfgData.Deezer.LowerQualityIfNotAvailable = false
+	c := New(&config.Config{File: cfgData, Session: cfgData})
+	c.loggedIn = true
+	c.bin = "definitely-not-a-real-yt-dlp-bin"
+	c.run = func(context.Context, string, ...string) ([]byte, error) {
+		return nil, fmt.Errorf("unexpected run call")
+	}
+	orig := baseURL
+	baseURL = ts.URL
+	defer func() { baseURL = orig }()
+
+	_, err := c.GetDownloadable(context.Background(), "42", 2)
+	if err == nil || !strings.Contains(err.Error(), "full-quality mode failed") {
+		t.Fatalf("expected full-quality failure error, got %v", err)
+	}
+}