streamrip-go/internal/provider/beatport/client.go

package beatport

import (
	"bytes"
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"net/http"
	"net/url"
	"strconv"
	"strings"
	"sync"
	"time"

	"streamrip-go/internal/config"
	"streamrip-go/internal/jsonutil"
	"streamrip-go/internal/netutil"
	"streamrip-go/internal/provider"
	"streamrip-go/internal/ratelimit"
	"streamrip-go/internal/verbose"
)

const (
	baseURL       = "https://api.beatport.com/v4"
	tokenEndpoint = "/auth/o/token/"
	authEndpoint  = "/auth/o/authorize/"
	loginEndpoint = "/auth/login/"
)

var (
	errMissingCredentials = errors.New("missing beatport credentials")
	errNotLoggedIn        = errors.New("beatport client not logged in")
)

type Client struct {
	cfg       *config.Config
	http      *http.Client
	limiter   *ratelimit.Limiter
	baseURL   string
	sessionID string

	// authMu serializes the token refresh / re-login path and guards loggedIn.
	// ensureToken is reached from apiRequest, which concurrent download workers
	// call, so without this several workers would refresh at once.
	authMu   sync.Mutex
	loggedIn bool
}

func New(cfg *config.Config) *Client {
	h := netutil.NewHTTPClient(40*time.Second, cfg.Session.Downloads.VerifySSL, cfg.Session.Downloads.MaxConnections)
	h.CheckRedirect = func(*http.Request, []*http.Request) error { return http.ErrUseLastResponse }
	return &Client{
		cfg:     cfg,
		http:    h,
		limiter: ratelimit.New(cfg.Session.Downloads.RequestsPerMinute),
		baseURL: baseURL,
	}
}

func (c *Client) Source() string { return "beatport" }

func (c *Client) LoggedIn() bool {
	c.authMu.Lock()
	defer c.authMu.Unlock()
	return c.loggedIn
}

func (c *Client) Login(ctx context.Context) error {
	c.authMu.Lock()
	defer c.authMu.Unlock()
	b := &c.cfg.Session.Beatport
	b.Username = strings.TrimSpace(b.Username)
	b.Password = strings.TrimSpace(b.Password)
	if b.Username == "" || b.Password == "" {
		return errMissingCredentials
	}
	if strings.TrimSpace(b.AccessToken) != "" && time.Now().Unix()+300 < b.TokenExpiry {
		c.loggedIn = true
		return nil
	}
	if strings.TrimSpace(b.RefreshToken) != "" {
		if err := c.refresh(ctx); err == nil {
			c.loggedIn = true
			return nil
		}
	}
	if err := c.loginPasswordFlow(ctx); err != nil {
		return err
	}
	c.loggedIn = true
	return nil
}

func (c *Client) GetMetadata(ctx context.Context, item, mediaType string) (map[string]any, error) {
	if !c.LoggedIn() {
		return nil, errNotLoggedIn
	}
	switch mediaType {
	case "track":
		track, err := c.getMap(ctx, "/catalog/tracks/"+url.PathEscape(strings.TrimSpace(item))+"/", nil)
		if err != nil {
			return nil, err
		}
		if relID := jsonutil.NestedString(track, "release", "id"); relID != "" {
			if rel, relErr := c.getRelease(ctx, relID); relErr == nil {
				track["release"] = rel
			}
		}
		return c.normalizeTrack(track), nil
	case "album":
		return c.getAlbumMetadata(ctx, item)
	case "playlist":
		return c.getPlaylistMetadata(ctx, item)
	case "chart":
		return c.getChartMetadata(ctx, strings.TrimPrefix(strings.TrimSpace(item), "chart:"))
	case "artist":
		artist, err := c.getMap(ctx, "/catalog/artists/"+url.PathEscape(strings.TrimSpace(item))+"/", nil)
		if err != nil {
			return nil, err
		}
		releases, err := c.getPaginated(ctx, "/catalog/releases/", url.Values{"artist_id": []string{strings.TrimSpace(item)}})
		if err != nil {
			return nil, err
		}
		return c.releaseCollectionMetadata(artist, releases), nil
	case "label":
		label, err := c.getMap(ctx, "/catalog/labels/"+url.PathEscape(strings.TrimSpace(item))+"/", nil)
		if err != nil {
			return nil, err
		}
		tracks, err := c.getTrackCollection(ctx, url.Values{"label_id": []string{strings.TrimSpace(item)}})
		if err != nil {
			return nil, err
		}
		return c.collectionMetadata(label, tracks), nil
	default:
		return nil, fmt.Errorf("unsupported beatport media type %q", mediaType)
	}
}

func (c *Client) Search(ctx context.Context, mediaType, query string, limit int) ([]map[string]any, error) {
	if !c.LoggedIn() {
		return nil, errNotLoggedIn
	}
	if limit <= 0 {
		limit = 25
	}
	var key string
	switch mediaType {
	case "track":
		key = "tracks"
	case "album":
		key = "releases"
	case "label":
		key = "labels"
	default:
		return nil, fmt.Errorf("unsupported beatport search media type %q", mediaType)
	}
	params := url.Values{}
	params.Set("q", query)
	params.Set("order_by", "-publish_date")
	params.Set("is_available_for_streaming", "true")
	resp, err := c.getMap(ctx, "/catalog/search/", params)
	if err != nil {
		return nil, err
	}
	items := sliceAny(resp[key])
	if limit < len(items) {
		items = items[:limit]
	}
	return []map[string]any{{"items": c.normalizeSearchItems(mediaType, items)}}, nil
}

func (c *Client) GetDownloadable(ctx context.Context, item string, quality int) (*provider.Downloadable, error) {
	if !c.LoggedIn() {
		return nil, errNotLoggedIn
	}
	q := beatportQuality(quality)
	params := url.Values{"quality": []string{q}}
	resp, err := c.getMap(ctx, "/catalog/tracks/"+url.PathEscape(strings.TrimSpace(item))+"/download/", params)
	if err != nil {
		return nil, err
	}
	location := strings.TrimSpace(jsonutil.StringFromAny(resp["location"]))
	if location == "" {
		return nil, errors.New("beatport download response missing location")
	}
	streamQuality := strings.TrimSpace(jsonutil.StringFromAny(resp["stream_quality"]))
	profile, ext := audioProfile(q, streamQuality)
	return &provider.Downloadable{URL: location, Extension: ext, Source: "beatport", TrackID: strings.TrimSpace(item), Audio: profile}, nil
}

func (c *Client) Close() error { return nil }

func (c *Client) getAlbumMetadata(ctx context.Context, id string) (map[string]any, error) {
	release, err := c.getRelease(ctx, id)
	if err != nil {
		return nil, err
	}
	tracks, err := c.getReleaseTracks(ctx, id)
	if err != nil {
		return nil, err
	}
	return c.normalizeRelease(release, tracks), nil
}

func (c *Client) getPlaylistMetadata(ctx context.Context, id string) (map[string]any, error) {
	if strings.HasPrefix(strings.TrimSpace(id), "chart:") {
		return c.getChartMetadata(ctx, strings.TrimPrefix(strings.TrimSpace(id), "chart:"))
	}
	playlist, err := c.getMap(ctx, "/catalog/playlists/"+url.PathEscape(strings.TrimSpace(id))+"/", nil)
	if err != nil {
		return nil, err
	}
	items, err := c.getPaginated(ctx, "/catalog/playlists/"+url.PathEscape(strings.TrimSpace(id))+"/tracks/", nil)
	if err != nil {
		return nil, err
	}
	tracks := make([]any, 0, len(items))
	for _, raw := range items {
		m, ok := raw.(map[string]any)
		if !ok {
			continue
		}
		if track, ok := m["track"].(map[string]any); ok {
			tracks = append(tracks, c.normalizeTrackListItem(track))
		}
	}
	return playlistMetadata(playlist, tracks), nil
}

func (c *Client) getChartMetadata(ctx context.Context, id string) (map[string]any, error) {
	chart, err := c.getMap(ctx, "/catalog/charts/"+url.PathEscape(strings.TrimSpace(id))+"/", nil)
	if err != nil {
		return nil, err
	}
	tracks, err := c.getPaginated(ctx, "/catalog/charts/"+url.PathEscape(strings.TrimSpace(id))+"/tracks/", nil)
	if err != nil {
		return nil, err
	}
	normalized := make([]any, 0, len(tracks))
	for _, raw := range tracks {
		if track, ok := raw.(map[string]any); ok {
			normalized = append(normalized, c.normalizeTrackListItem(track))
		}
	}
	return playlistMetadata(chart, normalized), nil
}

func (c *Client) getRelease(ctx context.Context, id string) (map[string]any, error) {
	return c.getMap(ctx, "/catalog/releases/"+url.PathEscape(strings.TrimSpace(id))+"/", nil)
}

func (c *Client) getReleaseTracks(ctx context.Context, id string) ([]any, error) {
	items, err := c.getPaginated(ctx, "/catalog/releases/"+url.PathEscape(strings.TrimSpace(id))+"/tracks/", nil)
	if err != nil {
		return nil, err
	}
	for _, raw := range items {
		if track, ok := raw.(map[string]any); ok {
			track["release"] = map[string]any{"id": id}
		}
	}
	return items, nil
}

func (c *Client) getTrackCollection(ctx context.Context, params url.Values) ([]any, error) {
	return c.getPaginated(ctx, "/catalog/tracks/", params)
}

func (c *Client) getPaginated(ctx context.Context, endpoint string, params url.Values) ([]any, error) {
	if params == nil {
		params = url.Values{}
	} else {
		params = cloneValues(params)
	}
	out := make([]any, 0)
	for page := 1; ; page++ {
		params.Set("page", strconv.Itoa(page))
		resp, err := c.getMap(ctx, endpoint, params)
		if err != nil {
			return nil, err
		}
		out = append(out, sliceAny(resp["results"])...)
		if strings.TrimSpace(jsonutil.StringFromAny(resp["next"])) == "" {
			break
		}
	}
	return out, nil
}

func (c *Client) getMap(ctx context.Context, endpoint string, params url.Values) (map[string]any, error) {
	resp, err := c.apiRequest(ctx, http.MethodGet, endpoint, params, nil, "")
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *Client) apiRequest(ctx context.Context, method, endpoint string, params url.Values, payload any, contentType string) (map[string]any, error) {
	if err := c.ensureToken(ctx); err != nil {
		return nil, err
	}
	resp, status, err := c.rawRequest(ctx, method, endpoint, params, payload, contentType, true)
	if err != nil {
		return nil, err
	}
	if status == http.StatusUnauthorized {
		if err = c.reauthorize(ctx); err != nil {
			return nil, err
		}
		resp, status, err = c.rawRequest(ctx, method, endpoint, params, payload, contentType, true)
		if err != nil {
			return nil, err
		}
	}
	if status < 200 || status >= 300 {
		return nil, fmt.Errorf("beatport request failed: status=%d body=%v", status, resp)
	}
	return resp, nil
}

func (c *Client) ensureToken(ctx context.Context) error {
	c.authMu.Lock()
	defer c.authMu.Unlock()
	return c.ensureTokenLocked(ctx)
}

// ensureTokenLocked requires c.authMu to be held.
func (c *Client) ensureTokenLocked(ctx context.Context) error {
	if strings.TrimSpace(c.cfg.Session.Beatport.AccessToken) != "" && time.Now().Unix()+300 < c.cfg.Session.Beatport.TokenExpiry {
		return nil
	}
	if strings.TrimSpace(c.cfg.Session.Beatport.RefreshToken) != "" {
		if err := c.refresh(ctx); err == nil {
			return nil
		}
	}
	return c.loginPasswordFlow(ctx)
}

// reauthorize forces a token refresh after a 401. Holding authMu means that
// when several workers get a 401 at once only the first re-authenticates and
// the rest reuse the resulting token.
func (c *Client) reauthorize(ctx context.Context) error {
	c.authMu.Lock()
	defer c.authMu.Unlock()
	c.cfg.Session.Beatport.TokenExpiry = 0
	if err := c.refresh(ctx); err != nil {
		if loginErr := c.loginPasswordFlow(ctx); loginErr != nil {
			return err
		}
	}
	return nil
}

func (c *Client) loginPasswordFlow(ctx context.Context) error {
	b := &c.cfg.Session.Beatport
	if strings.TrimSpace(b.Username) == "" || strings.TrimSpace(b.Password) == "" {
		return errMissingCredentials
	}
	loginResp, status, err := c.rawRequest(ctx, http.MethodPost, loginEndpoint, nil, map[string]string{"username": b.Username, "password": b.Password}, "application/json", false)
	if err != nil {
		return err
	}
	if status < 200 || status >= 300 {
		return fmt.Errorf("beatport login failed: status=%d body=%v", status, loginResp)
	}
	if c.sessionID == "" {
		return errors.New("beatport login response missing sessionid cookie")
	}
	code, err := c.authorize(ctx)
	if err != nil {
		return err
	}
	return c.issueToken(ctx, map[string]string{"client_id": c.appClientID(), "grant_type": "authorization_code", "code": code})
}

func (c *Client) authorize(ctx context.Context) (string, error) {
	params := url.Values{"client_id": []string{c.appClientID()}, "response_type": []string{"code"}}
	resp, status, err := c.rawRequest(ctx, http.MethodGet, authEndpoint, params, nil, "", false)
	if err != nil {
		return "", err
	}
	if status != http.StatusFound {
		return "", fmt.Errorf("beatport authorize failed: status=%d body=%v", status, resp)
	}
	code := strings.TrimSpace(jsonutil.StringFromAny(resp["code"]))
	if code == "" {
		return "", errors.New("beatport authorize redirect missing code")
	}
	return code, nil
}

func (c *Client) refresh(ctx context.Context) error {
	b := &c.cfg.Session.Beatport
	return c.issueToken(ctx, map[string]string{"client_id": c.appClientID(), "grant_type": "refresh_token", "refresh_token": b.RefreshToken})
}

func (c *Client) issueToken(ctx context.Context, payload map[string]string) error {
	resp, status, err := c.rawRequest(ctx, http.MethodPost, tokenEndpoint, nil, payload, "application/x-www-form-urlencoded", false)
	if err != nil {
		return err
	}
	if status < 200 || status >= 300 {
		return fmt.Errorf("beatport token request failed: status=%d body=%v", status, resp)
	}
	access := strings.TrimSpace(jsonutil.StringFromAny(resp["access_token"]))
	refresh := strings.TrimSpace(jsonutil.StringFromAny(resp["refresh_token"]))
	if access == "" {
		return errors.New("beatport token response missing access_token")
	}
	expiresIn := int64(jsonutil.IntFromAny(resp["expires_in"]))
	if expiresIn <= 0 {
		expiresIn = 3600
	}
	expiry := time.Now().Unix() + expiresIn
	if err := c.cfg.UpdateTokens(func(file, session *config.ConfigData) {
		session.Beatport.AccessToken = access
		if refresh != "" {
			session.Beatport.RefreshToken = refresh
		}
		session.Beatport.TokenExpiry = expiry
		file.Beatport.AccessToken = session.Beatport.AccessToken
		file.Beatport.RefreshToken = session.Beatport.RefreshToken
		file.Beatport.TokenExpiry = session.Beatport.TokenExpiry
	}); err != nil {
		verbose.Printf(verbose.V, "beatport: could not persist refreshed token: %v\n", err)
	}
	return nil
}

func (c *Client) rawRequest(ctx context.Context, method, endpoint string, params url.Values, payload any, contentType string, auth bool) (map[string]any, int, error) {
	if c.limiter != nil {
		if err := c.limiter.Wait(ctx); err != nil {
			return nil, 0, err
		}
	}
	var body io.Reader
	if payload != nil {
		switch contentType {
		case "application/json":
			b, err := json.Marshal(payload)
			if err != nil {
				return nil, 0, err
			}
			body = bytes.NewReader(b)
		case "application/x-www-form-urlencoded":
			vals := url.Values{}
			for k, v := range payload.(map[string]string) {
				vals.Set(k, v)
			}
			body = strings.NewReader(vals.Encode())
		default:
			return nil, 0, fmt.Errorf("unsupported beatport content type %q", contentType)
		}
	}
	u, err := url.Parse(strings.TrimRight(c.baseURL, "/") + endpoint)
	if err != nil {
		return nil, 0, err
	}
	if len(params) > 0 {
		u.RawQuery = params.Encode()
	}
	req, err := http.NewRequestWithContext(ctx, method, u.String(), body)
	if err != nil {
		return nil, 0, err
	}
	req.Header.Set("Accept", "application/json")
	req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36")
	if contentType != "" {
		req.Header.Set("Content-Type", contentType)
	}
	if auth && strings.TrimSpace(c.cfg.Session.Beatport.AccessToken) != "" {
		req.Header.Set("Authorization", "Bearer "+strings.TrimSpace(c.cfg.Session.Beatport.AccessToken))
	}
	if endpoint == authEndpoint && c.sessionID != "" {
		req.Header.Set("Cookie", "sessionid="+c.sessionID)
	}
	resp, err := c.http.Do(req)
	if err != nil {
		return nil, 0, err
	}
	defer func() { _ = resp.Body.Close() }()
	if endpoint == loginEndpoint {
		for _, cookie := range resp.Cookies() {
			if cookie.Name == "sessionid" {
				c.sessionID = cookie.Value
				break
			}
		}
	}
	if endpoint == authEndpoint && resp.StatusCode == http.StatusFound {
		loc := resp.Header.Get("Location")
		parsed, parseErr := url.Parse(loc)
		if parseErr == nil && strings.TrimSpace(parsed.Query().Get("code")) != "" {
			return map[string]any{"code": parsed.Query().Get("code")}, resp.StatusCode, nil
		}
		return map[string]any{}, resp.StatusCode, nil
	}
	var out map[string]any
	if err = json.NewDecoder(resp.Body).Decode(&out); err != nil {
		if errors.Is(err, io.EOF) {
			return map[string]any{}, resp.StatusCode, nil
		}
		if resp.StatusCode >= 200 && resp.StatusCode < 300 {
			return nil, resp.StatusCode, err
		}
		return map[string]any{}, resp.StatusCode, nil
	}
	return out, resp.StatusCode, nil
}

func (c *Client) normalizeRelease(raw map[string]any, tracks []any) map[string]any {
	id := jsonutil.StringFromAny(raw["id"])
	artist := c.releaseArtistNameForTracks(raw["artists"], tracks)
	trackRelease := cloneMap(raw)
	trackRelease["album_artist_name"] = artist
	items := make([]any, 0, len(tracks))
	for _, entry := range tracks {
		track, ok := entry.(map[string]any)
		if !ok {
			continue
		}
		track["release"] = trackRelease
		items = append(items, c.normalizeTrack(track))
	}
	return map[string]any{
		"id":                    id,
		"title":                 jsonutil.StringFromAny(raw["name"]),
		"artist":                map[string]any{"name": artist},
		"release_date_original": jsonutil.StringFromAny(raw["new_release_date"]),
		"tracks_count":          firstPositiveInt(jsonutil.IntFromAny(raw["track_count"]), len(items)),
		"maximum_bit_depth":     16,
		"maximum_sampling_rate": "44.1",
		"image":                 imageMap(raw["image"]),
		"tracks":                map[string]any{"items": items},
		"upc":                   jsonutil.StringFromAny(raw["upc"]),
		"label":                 raw["label"],
	}
}

func (c *Client) normalizeTrack(raw map[string]any) map[string]any {
	release := mapAny(raw["release"])
	trackArtistNames := artistNames(raw["artists"])
	artistName := jsonutil.DisplayArtistNames(trackArtistNames)
	artistID := firstArtistID(raw["artists"])
	albumArtist := strings.TrimSpace(jsonutil.StringFromAny(release["album_artist_name"]))
	if albumArtist == "" {
		albumArtist = c.releaseArtistName(release["artists"])
	}
	if albumArtist == "" {
		albumArtist = artistName
	}
	genreName := jsonutil.NestedString(raw, "genre", "name")
	if sub := jsonutil.NestedString(raw, "sub_genre", "name"); sub != "" {
		genreName = sub
	}
	date := jsonutil.FirstNonEmpty(jsonutil.StringFromAny(release["new_release_date"]), jsonutil.StringFromAny(raw["publish_date"]))
	track := map[string]any{
		"id":                    jsonutil.StringFromAny(raw["id"]),
		"title":                 jsonutil.StringFromAny(raw["name"]),
		"version":               jsonutil.StringFromAny(raw["mix_name"]),
		"artist":                map[string]any{"id": artistID, "name": artistName},
		"performer":             map[string]any{"id": artistID, "name": artistName},
		"artist_names":          trackArtistNames,
		"album":                 map[string]any{"id": jsonutil.StringFromAny(release["id"]), "title": jsonutil.StringFromAny(release["name"]), "artist": map[string]any{"name": albumArtist}, "image": imageMap(release["image"]), "release_date_original": date},
		"track_number":          jsonutil.IntFromAny(raw["number"]),
		"tracks_count":          jsonutil.IntFromAny(release["track_count"]),
		"release_date_original": date,
		"genre":                 map[string]any{"name": genreName},
		"isrc":                  jsonutil.StringFromAny(raw["isrc"]),
		"bpm":                   jsonutil.IntFromAny(raw["bpm"]),
		"source_track_id":       jsonutil.StringFromAny(raw["id"]),
		"source_album_id":       jsonutil.StringFromAny(release["id"]),
		"source_artist_id":      artistID,
		"maximum_bit_depth":     16,
		"maximum_sampling_rate": "44.1",
	}
	if keyName := jsonutil.NestedString(raw, "key", "name"); keyName != "" {
		track["key"] = keyName
	}
	return track
}

func (c *Client) normalizeTrackListItem(raw map[string]any) map[string]any {
	names := artistNames(raw["artists"])
	return map[string]any{
		"id":           jsonutil.StringFromAny(raw["id"]),
		"title":        jsonutil.StringFromAny(raw["name"]),
		"version":      jsonutil.StringFromAny(raw["mix_name"]),
		"artist":       map[string]any{"name": jsonutil.DisplayArtistNames(names)},
		"album":        map[string]any{"id": jsonutil.NestedString(raw, "release", "id"), "title": jsonutil.NestedString(raw, "release", "name")},
		"track_number": jsonutil.IntFromAny(raw["number"]),
	}
}

func (c *Client) collectionMetadata(raw map[string]any, tracks []any) map[string]any {
	items := make([]any, 0, len(tracks))
	for _, entry := range tracks {
		track, ok := entry.(map[string]any)
		if !ok {
			continue
		}
		items = append(items, c.normalizeTrackListItem(track))
	}
	return map[string]any{
		"id":           jsonutil.StringFromAny(raw["id"]),
		"name":         jsonutil.StringFromAny(raw["name"]),
		"title":        jsonutil.StringFromAny(raw["name"]),
		"tracks_count": len(items),
		"tracks":       map[string]any{"items": items},
	}
}

func (c *Client) releaseCollectionMetadata(raw map[string]any, releases []any) map[string]any {
	items := make([]any, 0, len(releases))
	for _, entry := range releases {
		release, ok := entry.(map[string]any)
		if !ok {
			continue
		}
		id := strings.TrimSpace(jsonutil.StringFromAny(release["id"]))
		if id == "" {
			continue
		}
		items = append(items, map[string]any{
			"id":                    id,
			"title":                 jsonutil.StringFromAny(release["name"]),
			"artist":                map[string]any{"name": c.releaseArtistName(release["artists"])},
			"tracks_count":          jsonutil.IntFromAny(release["track_count"]),
			"release_date_original": jsonutil.StringFromAny(release["new_release_date"]),
		})
	}
	return map[string]any{
		"id":     jsonutil.StringFromAny(raw["id"]),
		"name":   jsonutil.StringFromAny(raw["name"]),
		"title":  jsonutil.StringFromAny(raw["name"]),
		"albums": map[string]any{"items": items},
	}
}

func playlistMetadata(raw map[string]any, tracks []any) map[string]any {
	name := jsonutil.StringFromAny(raw["name"])
	return map[string]any{
		"id":           jsonutil.StringFromAny(raw["id"]),
		"name":         name,
		"title":        name,
		"tracks_count": firstPositiveInt(jsonutil.IntFromAny(raw["track_count"]), len(tracks)),
		"image":        imageMap(raw["image"]),
		"tracks":       map[string]any{"items": tracks},
	}
}

func (c *Client) normalizeSearchItems(mediaType string, items []any) []any {
	out := make([]any, 0, len(items))
	for _, raw := range items {
		m, ok := raw.(map[string]any)
		if !ok {
			continue
		}
		switch mediaType {
		case "track":
			out = append(out, c.normalizeTrackListItem(m))
		case "album":
			out = append(out, map[string]any{"id": jsonutil.StringFromAny(m["id"]), "title": jsonutil.StringFromAny(m["name"]), "artist": map[string]any{"name": c.releaseArtistName(m["artists"])}, "tracks_count": jsonutil.IntFromAny(m["track_count"]), "release_date_original": jsonutil.StringFromAny(m["new_release_date"])})
		case "label":
			out = append(out, map[string]any{"id": jsonutil.StringFromAny(m["id"]), "title": jsonutil.StringFromAny(m["name"]), "name": jsonutil.StringFromAny(m["name"])})
		}
	}
	return out
}

func beatportQuality(q int) string {
	switch q {
	case 1:
		return "medium"
	case 2:
		return "high"
	default:
		return "lossless"
	}
}

func audioProfile(quality, streamQuality string) (provider.AudioProfile, string) {
	s := strings.ToLower(strings.TrimSpace(streamQuality))
	switch {
	case strings.Contains(s, "flac") || quality == "lossless":
		return provider.AudioProfile{Container: "FLAC", Codec: "FLAC", Quality: "LOSSLESS", BitDepth: 16, SamplingRate: "44.1"}, "flac"
	case strings.Contains(s, "256") || quality == "high":
		return provider.AudioProfile{Container: "M4A", Codec: "AACLC", Quality: "HIGH", BitDepth: 16, SamplingRate: "44.1", BitrateKbps: 256}, "m4a"
	default:
		return provider.AudioProfile{Container: "M4A", Codec: "AACLC", Quality: "LOW", BitDepth: 16, SamplingRate: "44.1", BitrateKbps: 128}, "m4a"
	}
}

func artistNames(v any) []string {
	items := sliceAny(v)
	names := make([]string, 0, len(items))
	for _, raw := range items {
		m, ok := raw.(map[string]any)
		if !ok {
			continue
		}
		if name := strings.TrimSpace(jsonutil.StringFromAny(m["name"])); name != "" {
			names = append(names, name)
		}
	}
	return names
}

func (c *Client) releaseArtistName(v any) string {
	items := sliceAny(v)
	threshold := c.cfg.Session.Beatport.VariousArtistsThreshold
	if threshold >= 0 && len(items) > threshold {
		return "Various Artists"
	}
	return jsonutil.DisplayArtistNames(artistNames(v))
}

func (c *Client) releaseArtistNameForTracks(releaseArtists any, tracks []any) string {
	common := commonReleaseArtists(releaseArtists, tracks)
	if len(common) > 0 {
		return jsonutil.DisplayArtistNames(artistNames(common))
	}
	return c.releaseArtistName(releaseArtists)
}

func commonReleaseArtists(releaseArtists any, tracks []any) []any {
	items := sliceAny(releaseArtists)
	if len(items) == 0 || len(tracks) == 0 {
		return nil
	}
	counts := map[string]int{}
	trackCount := 0
	for _, rawTrack := range tracks {
		track, ok := rawTrack.(map[string]any)
		if !ok {
			continue
		}
		trackCount++
		seen := map[string]bool{}
		for _, rawArtist := range sliceAny(track["artists"]) {
			if key := artistIdentity(rawArtist); key != "" {
				seen[key] = true
			}
		}
		for key := range seen {
			counts[key]++
		}
	}
	if trackCount == 0 {
		return nil
	}
	common := make([]any, 0)
	for _, rawArtist := range items {
		if key := artistIdentity(rawArtist); key != "" && counts[key] == trackCount {
			common = append(common, rawArtist)
		}
	}
	return common
}

func artistIdentity(raw any) string {
	m, ok := raw.(map[string]any)
	if !ok {
		return ""
	}
	if id := strings.TrimSpace(jsonutil.StringFromAny(m["id"])); id != "" {
		return "id:" + id
	}
	if name := strings.TrimSpace(jsonutil.StringFromAny(m["name"])); name != "" {
		return "name:" + strings.ToLower(name)
	}
	return ""
}

func cloneMap(in map[string]any) map[string]any {
	out := make(map[string]any, len(in))
	for k, v := range in {
		out[k] = v
	}
	return out
}

func firstArtistID(v any) string {
	items := sliceAny(v)
	if len(items) == 0 {
		return ""
	}
	m, _ := items[0].(map[string]any)
	return jsonutil.StringFromAny(m["id"])
}

func imageMap(v any) map[string]any {
	m := mapAny(v)
	dynamic := strings.TrimSpace(jsonutil.StringFromAny(m["dynamic_uri"]))
	uri := strings.TrimSpace(jsonutil.StringFromAny(m["uri"]))
	if dynamic != "" {
		return map[string]any{
			"original":   strings.ReplaceAll(dynamic, "{w}x{h}", "1400x1400"),
			"extralarge": strings.ReplaceAll(dynamic, "{w}x{h}", "1000x1000"),
			"large":      strings.ReplaceAll(dynamic, "{w}x{h}", "500x500"),
			"small":      strings.ReplaceAll(dynamic, "{w}x{h}", "250x250"),
			"thumbnail":  strings.ReplaceAll(dynamic, "{w}x{h}", "100x100"),
		}
	}
	if uri != "" {
		return map[string]any{"original": uri, "large": uri}
	}
	return nil
}

func mapAny(v any) map[string]any {
	m, _ := v.(map[string]any)
	if m == nil {
		return map[string]any{}
	}
	return m
}

func sliceAny(v any) []any {
	s, ok := v.([]any)
	if !ok {
		return nil
	}
	return s
}

func firstPositiveInt(vals ...int) int {
	for _, v := range vals {
		if v > 0 {
			return v
		}
	}
	return 0
}

func cloneValues(in url.Values) url.Values {
	out := url.Values{}
	for k, vals := range in {
		out[k] = append([]string(nil), vals...)
	}
	return out
}

// appClientID reads the vendor OAuth app credential from config, falling back
// to the built-in default.
func (c *Client) appClientID() string {
	if v := strings.TrimSpace(c.cfg.Session.Beatport.AppClientID); v != "" {
		return v
	}
	return config.DefaultBeatportAppClientID
}