fix tidal playlist metadata and retries

internal/provider/tidal/client_test.go

@@ -6,6 +6,7 @@ import (
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
+	"net/url"
 	"reflect"
 	"strconv"
 	"testing"
@@ -238,6 +239,83 @@ func TestGetMetadataTrackIgnoresLyricsEndpointFailure(t *testing.T) {
 	}
 }
 
+func TestAPIRequestRetriesTooManyRequests(t *testing.T) {
+	calls := 0
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/v1/tracks/42" {
+			w.WriteHeader(http.StatusNotFound)
+			return
+		}
+		calls++
+		if calls == 1 {
+			w.Header().Set("Retry-After", "0")
+			w.WriteHeader(http.StatusTooManyRequests)
+			_, _ = w.Write([]byte("slow down"))
+			return
+		}
+		_ = json.NewEncoder(w).Encode(map[string]any{"id": 42, "title": "Song"})
+	}))
+	defer ts.Close()
+
+	cfgData := config.DefaultConfigData()
+	cfgData.Downloads.RequestsPerMinute = 0
+	cfgData.Tidal.AccessToken = "token"
+	cfgData.Tidal.CountryCode = "US"
+	c := New(&config.Config{File: cfgData, Session: cfgData})
+	c.baseURL = ts.URL + "/v1"
+
+	resp, status, err := c.apiRequest(context.Background(), "tracks/42", nil, c.baseURL)
+	if err != nil {
+		t.Fatalf("apiRequest() err = %v", err)
+	}
+	if status != http.StatusOK {
+		t.Fatalf("status = %d, want %d", status, http.StatusOK)
+	}
+	if calls != 2 {
+		t.Fatalf("calls = %d, want 2", calls)
+	}
+	if stringify(resp["title"]) != "Song" {
+		t.Fatalf("title = %q, want Song", stringify(resp["title"]))
+	}
+}
+
+func TestAPIPostRetriesTooManyRequests(t *testing.T) {
+	calls := 0
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/token" {
+			w.WriteHeader(http.StatusNotFound)
+			return
+		}
+		calls++
+		if calls == 1 {
+			w.Header().Set("Retry-After", "0")
+			w.WriteHeader(http.StatusTooManyRequests)
+			_, _ = w.Write([]byte("slow down"))
+			return
+		}
+		_ = json.NewEncoder(w).Encode(map[string]any{"access_token": "fresh-token"})
+	}))
+	defer ts.Close()
+
+	cfgData := config.DefaultConfigData()
+	cfgData.Downloads.RequestsPerMinute = 0
+	c := New(&config.Config{File: cfgData, Session: cfgData})
+
+	resp, status, err := c.apiPost(context.Background(), ts.URL+"/token", url.Values{"grant_type": []string{"refresh_token"}}, false)
+	if err != nil {
+		t.Fatalf("apiPost() err = %v", err)
+	}
+	if status != http.StatusOK {
+		t.Fatalf("status = %d, want %d", status, http.StatusOK)
+	}
+	if calls != 2 {
+		t.Fatalf("calls = %d, want 2", calls)
+	}
+	if stringify(resp["access_token"]) != "fresh-token" {
+		t.Fatalf("access_token = %q, want fresh-token", stringify(resp["access_token"]))
+	}
+}
+
 func TestGetDownloadablePrefersAtmosWhenEnabled(t *testing.T) {
 	var calls []string
 	allImmersive := true