add monitor sync jobs and duplicate-safe qobuz updates

.env.example

@@ -4,6 +4,7 @@ SPOTIFY_SCOPES=playlist-read-private,playlist-read-collaborative,user-library-re
 QTRANSFER_SPOTIFY_MANUAL_CODE=true
 QTRANSFER_SESSION_FILE=~/.config/qtransfer/session.json
 QTRANSFER_REMEMBER_CREDS=true
+QTRANSFER_CONFIG=
 
 QOBUZ_USERNAME=
 QOBUZ_PASSWORD=
@@ -21,3 +22,5 @@ QTRANSFER_MONITOR=false
 QTRANSFER_MONITOR_ONCE=false
 QTRANSFER_MONITOR_TRANSFER=false
 QTRANSFER_MONITOR_INTERVAL=5m
+QTRANSFER_SYNC_MODE=append
+QTRANSFER_TARGET_PLAYLIST_ID=0

README.md

@@ -9,7 +9,7 @@ Spotify -> Qobuz playlist transfer tool in Go.
 - Session cache for Spotify/Qobuz credentials and tokens (so you do not need to re-enter each run).
 - Fetches all Spotify playlists and liked songs.
 - Playlist URL mode (`--playlist-url`) for direct targeted transfers.
-- Monitor mode to detect playlist updates (`--monitor`) with optional auto-transfer (`--monitor-transfer`).
+- Monitor mode to detect playlist updates (`--monitor`) with optional sync-to-Qobuz (`--monitor-transfer`) and sync modes (`--sync-mode`).
 - Interactive selection prompt (or non-interactive flags).
 - Creates Qobuz playlists and fills them with best-effort track matches.
 - Transfers liked songs into a dedicated playlist (not favorites).
@@ -58,13 +58,16 @@ Credentials/tokens are cached in `~/.config/qtransfer/session.json` by default.
 - `--liked`: include liked songs as a generated Qobuz playlist
 - `--playlist "Name"` (repeatable): transfer specific playlists by exact name
 - `--playlist-url "..."` (repeatable): transfer specific Spotify playlists by URL/URI/ID
+- `--config sync.toml`: TOML config with global options and per-playlist monitor sync jobs
 - `--spotify-manual-code=true|false`: paste callback URL/code manually or use local callback server
 - `--remember-creds=true|false`: persist/reuse tokens and credentials in session file
 - `--session-file path`: custom session file path (default `~/.config/qtransfer/session.json`)
 - `--monitor`: monitor selected playlists for updates
 - `--monitor-interval 5m`: monitor polling interval
 - `--monitor-once`: run one monitor check and exit
-- `--monitor-transfer`: in monitor mode, transfer only changed playlists
+- `--monitor-transfer`: in monitor mode, sync changed playlists to Qobuz
+- `--sync-mode append|mirror`: append only, or mirror source by recreating target playlist
+- `--target-playlist-id 123456`: bind single monitored source playlist to an existing Qobuz playlist ID
 - `--qobuz-self-test`: run Qobuz login/verify/search checks and exit (skips Spotify)
 - `--qobuz-self-test-write`: when self-test is enabled, also create a test playlist and add one track
 - `--qobuz-self-test-query "..."`: search query used during self-test
@@ -102,6 +105,49 @@ Monitor selected playlists for changes:
   --monitor --monitor-interval 2m
 ```
 
+Monitor with append-only sync (never removes from Qobuz):
+
+```bash
+./qtransfer \
+  --playlist-url "https://open.spotify.com/playlist/37i9dQZF1DX0XUsuxWHRQd" \
+  --monitor --monitor-transfer --sync-mode append --monitor-interval 2m
+```
+
+Monitor with mirror sync (recreates playlist on change):
+
+```bash
+./qtransfer \
+  --playlist-url "https://open.spotify.com/playlist/37i9dQZF1DX0XUsuxWHRQd" \
+  --monitor --monitor-transfer --sync-mode mirror --monitor-interval 2m
+```
+
+Config-file mode:
+
+```bash
+./qtransfer --config sync.toml
+```
+
+Example `sync.toml`:
+
+```toml
+[global]
+monitor = true
+monitor_transfer = true
+monitor_interval = "10m"
+sync_mode = "append"
+include_liked = true
+
+[[playlist]]
+url = "https://open.spotify.com/playlist/37i9dQZF1DX0XUsuxWHRQd"
+sync_mode = "append"
+target_playlist_id = 61646089
+
+[[playlist]]
+url = "spotify:playlist:37i9dQZF1DWY4xHQp97fN6"
+sync_mode = "mirror"
+enabled = true
+```
+
 Login command:
 
 ```bash
@@ -122,10 +168,13 @@ Logout command (removes cached session):
 - `QTRANSFER_SPOTIFY_MANUAL_CODE` (optional, defaults to true)
 - `QTRANSFER_SESSION_FILE` (optional)
 - `QTRANSFER_REMEMBER_CREDS` (optional, defaults to true)
+- `QTRANSFER_CONFIG` (optional)
 - `QTRANSFER_MONITOR` (optional)
 - `QTRANSFER_MONITOR_ONCE` (optional)
 - `QTRANSFER_MONITOR_TRANSFER` (optional)
 - `QTRANSFER_MONITOR_INTERVAL` (optional)
+- `QTRANSFER_SYNC_MODE` (optional: append|mirror)
+- `QTRANSFER_TARGET_PLAYLIST_ID` (optional, monitor mode only)
 - `QTRANSFER_QOBUZ_SELF_TEST` (optional)
 - `QTRANSFER_QOBUZ_SELF_TEST_WRITE` (optional)
 - `QTRANSFER_QOBUZ_SELF_TEST_QUERY` (optional)

cmd/qtransfer/main.go

@@ -5,15 +5,18 @@ import (
 	"context"
 	"crypto/sha1"
 	"encoding/hex"
+	"errors"
 	"fmt"
 	"os"
 	"os/signal"
 	"sort"
 	"strings"
+	"sync"
 	"syscall"
 	"time"
 
 	"qtransfer/internal/config"
+	"qtransfer/internal/jobconfig"
 	"qtransfer/internal/match"
 	"qtransfer/internal/model"
 	"qtransfer/internal/qobuz"
@@ -30,6 +33,11 @@ type sourceSelection struct {
 	IncludeLiked bool
 }
 
+type monitorPlan struct {
+	SyncMode         string
+	TargetPlaylistID int64
+}
+
 func main() {
 	if err := run(); err != nil {
 		fmt.Fprintf(os.Stderr, "Error: %v\n", err)
@@ -54,6 +62,9 @@ func run() error {
 		sess.Spotify = session.SpotifyState{}
 		sess.Qobuz = session.QobuzState{}
 	}
+	if sess.Playlists == nil {
+		sess.Playlists = map[string]session.PlaylistSyncRef{}
+	}
 	applySessionDefaults(&cfg, &sess)
 
 	if cfg.Command == "login" {
@@ -69,6 +80,26 @@ func run() error {
 		return err
 	}
 
+	fileCfg := jobconfig.File{}
+	if strings.TrimSpace(cfg.ConfigFile) != "" {
+		loaded, err := jobconfig.Load(cfg.ConfigFile)
+		if err != nil {
+			return err
+		}
+		fileCfg = loaded
+		if err := applyFileGlobals(&cfg, fileCfg.Global); err != nil {
+			return err
+		}
+	}
+
+	planURLs, monitorPlans, err := buildPlaylistPlans(cfg, fileCfg.Playlists)
+	if err != nil {
+		return err
+	}
+	if len(planURLs) > 0 {
+		cfg.PlaylistURLs = planURLs
+	}
+
 	spToken, err := authenticateSpotify(ctx, cfg, &sess)
 	if err != nil {
 		return fmt.Errorf("spotify auth failed: %w", err)
@@ -86,7 +117,7 @@ func run() error {
 	}
 
 	if cfg.Monitor {
-		if err := runMonitorMode(ctx, cfg, sp, &sess, selection); err != nil {
+		if err := runMonitorMode(ctx, cfg, sp, &sess, selection, monitorPlans); err != nil {
 			return err
 		}
 		return persistSession(cfg, sess)
@@ -264,17 +295,24 @@ func prompt(scanner *bufio.Scanner, label, defaultValue string) string {
 	return v
 }
 
-func runMonitorMode(ctx context.Context, cfg config.Config, sp *spotify.Client, sess *session.Data, selection sourceSelection) error {
+func runMonitorMode(ctx context.Context, cfg config.Config, sp *spotify.Client, sess *session.Data, selection sourceSelection, plans map[string]monitorPlan) error {
 	if len(selection.Playlists) == 0 && !selection.IncludeLiked {
 		return fmt.Errorf("monitor mode requires at least one playlist or --liked")
 	}
+	if sess.Playlists == nil {
+		sess.Playlists = map[string]session.PlaylistSyncRef{}
+	}
 
 	fmt.Println("Starting monitor mode...")
 	fmt.Printf("Watching %d playlist(s)", len(selection.Playlists))
 	if selection.IncludeLiked {
 		fmt.Printf(" + liked songs")
 	}
-	fmt.Printf(" | interval=%s\n", cfg.MonitorInterval)
+	fmt.Printf(" | interval=%s", cfg.MonitorInterval)
+	if cfg.MonitorTransfer {
+		fmt.Printf(" | sync-mode=%s", cfg.SyncMode)
+	}
+	fmt.Println()
 
 	playlistIDs := make([]string, 0, len(selection.Playlists))
 	for _, p := range selection.Playlists {
@@ -290,7 +328,7 @@ func runMonitorMode(ctx context.Context, cfg config.Config, sp *spotify.Client,
 			return err
 		}
 		matcher = match.NewMatcher(qb)
-		fmt.Println("Monitor transfer mode enabled: changed playlists will be transferred.")
+		fmt.Println("Monitor transfer mode enabled: changed playlists will be synced to Qobuz.")
 	}
 
 	prev := cloneMap(sess.Monitor)
@@ -335,25 +373,24 @@ func runMonitorMode(ctx context.Context, cfg config.Config, sp *spotify.Client,
 		fmt.Printf("[%s] Updated: %s\n", time.Now().Format("15:04:05"), strings.Join(names, ", "))
 
 		if cfg.MonitorTransfer && qb != nil && matcher != nil {
-			transferCfg := transfer.Config{
+			for _, pl := range changedPlaylists {
-				DryRun:          cfg.DryRun,
+				key := "playlist:" + pl.SourceID
-				PublicPlaylists: cfg.PublicPlaylists,
+				plan := plans[pl.SourceID]
-				Concurrency:     cfg.Concurrency,
+				if err := syncChangedPlaylist(ctx, cfg, qb, matcher, key, pl, plan, sess); err != nil {
-				LikedName:       cfg.LikedPlaylist,
+					fmt.Printf("Sync error for %s: %v\n", pl.Name, err)
-				Progress: func(msg string) {
+					curr[key] = prev[key]
-					fmt.Printf("\r%-140s", msg)
+				}
-				},
 			}
-
-			likedToTransfer := []model.Track{}
 			if likedChanged {
-				likedToTransfer = currentLiked
+				plan := monitorPlan{SyncMode: cfg.SyncMode}
+				likedPlaylist := model.Playlist{Name: cfg.LikedPlaylist, Tracks: currentLiked}
+				if err := syncChangedPlaylist(ctx, cfg, qb, matcher, "liked", likedPlaylist, plan, sess); err != nil {
+					fmt.Printf("Sync error for liked songs: %v\n", err)
+					curr["liked"] = prev["liked"]
 				}
-			if _, err := transfer.Run(ctx, transferCfg, qb, matcher, changedPlaylists, likedToTransfer, likedChanged); err != nil {
-				return fmt.Errorf("monitor transfer failed: %w", err)
 			}
 			fmt.Print("\r")
-			fmt.Println("Monitor transfer cycle complete.                                                         ")
+			fmt.Println("Monitor sync cycle complete.                                                             ")
 		}
 
 		prev = curr
@@ -525,6 +562,114 @@ func resolvePlaylistIDs(inputs []string) ([]string, error) {
 	return out, nil
 }
 
+func applyFileGlobals(cfg *config.Config, g jobconfig.GlobalConfig) error {
+	if g.Monitor != nil {
+		cfg.Monitor = *g.Monitor
+	}
+	if g.MonitorOnce != nil {
+		cfg.MonitorOnce = *g.MonitorOnce
+	}
+	if g.MonitorTransfer != nil {
+		cfg.MonitorTransfer = *g.MonitorTransfer
+	}
+	if strings.TrimSpace(g.MonitorInterval) != "" {
+		d, err := time.ParseDuration(strings.TrimSpace(g.MonitorInterval))
+		if err != nil {
+			return fmt.Errorf("invalid global monitor_interval %q: %w", g.MonitorInterval, err)
+		}
+		cfg.MonitorInterval = d
+	}
+	if strings.TrimSpace(g.SyncMode) != "" {
+		cfg.SyncMode = strings.ToLower(strings.TrimSpace(g.SyncMode))
+	}
+	if g.IncludeLiked != nil {
+		cfg.IncludeLiked = *g.IncludeLiked
+	}
+	if g.DryRun != nil {
+		cfg.DryRun = *g.DryRun
+	}
+	if g.PublicPlaylists != nil {
+		cfg.PublicPlaylists = *g.PublicPlaylists
+	}
+	if g.Concurrency != nil {
+		cfg.Concurrency = *g.Concurrency
+	}
+	if strings.TrimSpace(g.ReportPath) != "" {
+		cfg.ReportPath = strings.TrimSpace(g.ReportPath)
+	}
+
+	return cfg.Validate()
+}
+
+func buildPlaylistPlans(cfg config.Config, fileEntries []jobconfig.PlaylistEntry) ([]string, map[string]monitorPlan, error) {
+	urls := make([]string, 0, len(cfg.PlaylistURLs)+len(fileEntries))
+	for _, u := range cfg.PlaylistURLs {
+		u = strings.TrimSpace(u)
+		if u != "" {
+			urls = append(urls, u)
+		}
+	}
+
+	plans := map[string]monitorPlan{}
+
+	for _, raw := range urls {
+		id, err := spotify.ParsePlaylistID(raw)
+		if err != nil {
+			return nil, nil, fmt.Errorf("invalid playlist-url %q: %w", raw, err)
+		}
+		plans[id] = monitorPlan{SyncMode: cfg.SyncMode, TargetPlaylistID: cfg.TargetPlaylistID}
+	}
+
+	for i, entry := range fileEntries {
+		if !entry.IsEnabled() {
+			continue
+		}
+		raw := strings.TrimSpace(entry.URL)
+		id, err := spotify.ParsePlaylistID(raw)
+		if err != nil {
+			return nil, nil, fmt.Errorf("invalid config playlist entry %d url %q: %w", i+1, entry.URL, err)
+		}
+		mode := strings.ToLower(strings.TrimSpace(entry.SyncMode))
+		if mode == "" {
+			mode = cfg.SyncMode
+		}
+		if mode == "" {
+			mode = "append"
+		}
+		if entry.TargetPlaylistID > 0 && mode == "mirror" {
+			return nil, nil, fmt.Errorf("playlist entry %d cannot use mirror mode with target_playlist_id", i+1)
+		}
+		plans[id] = monitorPlan{SyncMode: mode, TargetPlaylistID: entry.TargetPlaylistID}
+		urls = append(urls, raw)
+	}
+
+	if cfg.TargetPlaylistID > 0 {
+		uniqueIDs := map[string]struct{}{}
+		for id := range plans {
+			uniqueIDs[id] = struct{}{}
+		}
+		if len(uniqueIDs) != 1 {
+			return nil, nil, fmt.Errorf("--target-playlist-id can only be used with exactly one source playlist URL")
+		}
+	}
+
+	seen := map[string]struct{}{}
+	deduped := make([]string, 0, len(urls))
+	for _, u := range urls {
+		u = strings.TrimSpace(u)
+		if u == "" {
+			continue
+		}
+		if _, ok := seen[u]; ok {
+			continue
+		}
+		seen[u] = struct{}{}
+		deduped = append(deduped, u)
+	}
+
+	return deduped, plans, nil
+}
+
 func buildFingerprintMap(playlists []model.Playlist, liked []model.Track, includeLiked bool) map[string]string {
 	m := make(map[string]string, len(playlists)+1)
 	for _, p := range playlists {
@@ -623,6 +768,9 @@ func persistSession(cfg config.Config, sess session.Data) error {
 	if sess.Monitor == nil {
 		sess.Monitor = map[string]string{}
 	}
+	if sess.Playlists == nil {
+		sess.Playlists = map[string]session.PlaylistSyncRef{}
+	}
 	return session.Save(cfg.SessionPath, sess)
 }
 
@@ -634,6 +782,168 @@ func cloneMap(in map[string]string) map[string]string {
 	return out
 }
 
+func syncChangedPlaylist(ctx context.Context, cfg config.Config, qb *qobuz.Client, matcher *match.Matcher, key string, pl model.Playlist, plan monitorPlan, sess *session.Data) error {
+	mode := strings.ToLower(strings.TrimSpace(plan.SyncMode))
+	if mode == "" {
+		mode = cfg.SyncMode
+	}
+	if mode == "" {
+		mode = "append"
+	}
+	if plan.TargetPlaylistID > 0 && mode == "mirror" {
+		return fmt.Errorf("mirror mode is not supported with explicit target playlist id (%d)", plan.TargetPlaylistID)
+	}
+
+	prev := sess.Playlists[key]
+	matchedIDs, unmatched := matchPlaylistTracks(ctx, matcher, pl.Tracks, cfg.Concurrency, func(done, total int) {
+		fmt.Printf("\r%-140s", fmt.Sprintf("Matching %s (%d/%d)", pl.Name, done, total))
+	})
+	matchedIDs = uniqueIDs(matchedIDs)
+	fmt.Print("\r")
+
+	fingerprint := playlistFingerprint(pl)
+	if key == "liked" {
+		fingerprint = trackListFingerprint(pl.Tracks)
+	}
+
+	if cfg.DryRun {
+		fmt.Printf("Dry-run sync %s: matched=%d/%d unmatched=%d\n", pl.Name, len(matchedIDs), len(pl.Tracks), len(unmatched))
+		sess.Playlists[key] = session.PlaylistSyncRef{
+			SourceName:      pl.Name,
+			QobuzPlaylistID: prev.QobuzPlaylistID,
+			Fingerprint:     fingerprint,
+		}
+		return nil
+	}
+
+	targetID := prev.QobuzPlaylistID
+	if plan.TargetPlaylistID > 0 {
+		targetID = plan.TargetPlaylistID
+	}
+	if mode == "mirror" && targetID > 0 {
+		if err := qb.DeletePlaylist(ctx, targetID); err != nil {
+			fmt.Printf("Warning: failed deleting old playlist %d for mirror sync: %v\n", targetID, err)
+		}
+		targetID = 0
+	}
+
+	if targetID == 0 {
+		createdID, err := qb.CreatePlaylist(ctx, pl.Name, sanitizeDescription(pl.Description), cfg.PublicPlaylists)
+		if err != nil {
+			return fmt.Errorf("create qobuz playlist: %w", err)
+		}
+		targetID = createdID
+	}
+
+	if len(matchedIDs) > 0 {
+		if err := qb.AddTracksToPlaylist(ctx, targetID, matchedIDs); err != nil {
+			if errors.Is(err, qobuz.ErrDuplicateTracks) {
+				fmt.Printf("No new tracks added for %s: matched tracks already exist in Qobuz playlist %d.\n", pl.Name, targetID)
+			} else {
+				return fmt.Errorf("add tracks to qobuz playlist %d: %w", targetID, err)
+			}
+		}
+	}
+
+	sess.Playlists[key] = session.PlaylistSyncRef{
+		SourceName:      pl.Name,
+		QobuzPlaylistID: targetID,
+		Fingerprint:     fingerprint,
+	}
+
+	fmt.Printf("Synced %s (%s): qobuz=%d matched=%d/%d unmatched=%d\n", pl.Name, mode, targetID, len(matchedIDs), len(pl.Tracks), len(unmatched))
+	return nil
+}
+
+func matchPlaylistTracks(ctx context.Context, matcher *match.Matcher, tracks []model.Track, concurrency int, progress func(done, total int)) ([]int64, []model.MatchedTrack) {
+	if concurrency < 1 {
+		concurrency = 1
+	}
+
+	type job struct {
+		idx int
+		trk model.Track
+	}
+	type out struct {
+		idx int
+		res model.MatchedTrack
+	}
+
+	jobs := make(chan job)
+	results := make(chan out)
+
+	var wg sync.WaitGroup
+	for i := 0; i < concurrency; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			for j := range jobs {
+				m := matcher.MatchTrack(ctx, j.trk)
+				results <- out{idx: j.idx, res: m}
+			}
+		}()
+	}
+
+	go func() {
+		for i, t := range tracks {
+			jobs <- job{idx: i, trk: t}
+		}
+		close(jobs)
+		wg.Wait()
+		close(results)
+	}()
+
+	ordered := make([]model.MatchedTrack, len(tracks))
+	total := len(tracks)
+	step := 1
+	if total > 100 {
+		step = total / 100
+	}
+	done := 0
+	for r := range results {
+		ordered[r.idx] = r.res
+		done++
+		if progress != nil && (done == 1 || done == total || done%step == 0) {
+			progress(done, total)
+		}
+	}
+
+	matched := make([]int64, 0, len(tracks))
+	unmatched := make([]model.MatchedTrack, 0)
+	for _, r := range ordered {
+		if r.Matched && r.QobuzID > 0 {
+			matched = append(matched, r.QobuzID)
+		} else {
+			unmatched = append(unmatched, r)
+		}
+	}
+	return matched, unmatched
+}
+
+func uniqueIDs(ids []int64) []int64 {
+	seen := map[int64]struct{}{}
+	out := make([]int64, 0, len(ids))
+	for _, id := range ids {
+		if id == 0 {
+			continue
+		}
+		if _, ok := seen[id]; ok {
+			continue
+		}
+		seen[id] = struct{}{}
+		out = append(out, id)
+	}
+	return out
+}
+
+func sanitizeDescription(s string) string {
+	s = strings.TrimSpace(s)
+	if len(s) <= 1000 {
+		return s
+	}
+	return s[:1000]
+}
+
 func printSummary(rep model.TransferReport, reportPath string, elapsed time.Duration, dryRun bool) {
 	mode := "TRANSFER"
 	if dryRun {

go.mod

@@ -1,3 +1,5 @@
 module qtransfer
 
 go 1.22
+
+require github.com/BurntSushi/toml v1.6.0

go.sum

@@ -0,0 +1,2 @@
+github.com/BurntSushi/toml v1.6.0 h1:dRaEfpa2VI55EwlIW72hMRHdWouJeRF7TPYhI+AUQjk=
+github.com/BurntSushi/toml v1.6.0/go.mod h1:ukJfTF/6rtPPRCnwkur4qwRxa8vTRFBF0uk2lLoLwho=

internal/config/config.go

@@ -14,6 +14,7 @@ import (
 
 type Config struct {
 	Command          string
+	ConfigFile       string
 	SpotifyClientID  string
 	SpotifyRedirect  string
 	SpotifyScopes    []string
@@ -31,6 +32,8 @@ type Config struct {
 	MonitorOnce      bool
 	MonitorTransfer  bool
 	MonitorInterval  time.Duration
+	SyncMode         string
+	TargetPlaylistID int64
 	LikedPlaylist    string
 	DryRun           bool
 	ReportPath       string
@@ -80,6 +83,7 @@ func Load() (Config, error) {
 	defaultAppSecret := envOr("QOBUZ_APP_SECRET", "e79f8b9be485692b0e5f9dd895826368")
 	defaultConcurrency := envIntOr("QTRANSFER_CONCURRENCY", 4)
 
+	flag.StringVar(&cfg.ConfigFile, "config", envOr("QTRANSFER_CONFIG", ""), "Path to TOML config file with playlist sync jobs")
 	flag.StringVar(&cfg.SpotifyClientID, "spotify-client-id", envOr("SPOTIFY_CLIENT_ID", ""), "Spotify app client ID")
 	flag.StringVar(&cfg.SpotifyRedirect, "spotify-redirect-uri", envOr("SPOTIFY_REDIRECT_URI", "http://127.0.0.1:8888/callback"), "Spotify OAuth redirect URI")
 	scopes := flag.String("spotify-scopes", envOr("SPOTIFY_SCOPES", defaultScopes), "Comma-separated Spotify OAuth scopes")
@@ -96,8 +100,10 @@ func Load() (Config, error) {
 	flag.StringVar(&cfg.QobuzTestQuery, "qobuz-self-test-query", envOr("QTRANSFER_QOBUZ_SELF_TEST_QUERY", "Daft Punk One More Time"), "Search query used for --qobuz-self-test")
 	flag.BoolVar(&cfg.Monitor, "monitor", envBoolOr("QTRANSFER_MONITOR", false), "Monitor selected playlists for updates")
 	flag.BoolVar(&cfg.MonitorOnce, "monitor-once", envBoolOr("QTRANSFER_MONITOR_ONCE", false), "Run a single monitor check then exit")
-	flag.BoolVar(&cfg.MonitorTransfer, "monitor-transfer", envBoolOr("QTRANSFER_MONITOR_TRANSFER", false), "When monitoring, transfer playlists that changed")
+	flag.BoolVar(&cfg.MonitorTransfer, "monitor-transfer", envBoolOr("QTRANSFER_MONITOR_TRANSFER", false), "When monitoring, sync changed playlists to Qobuz")
 	flag.DurationVar(&cfg.MonitorInterval, "monitor-interval", envDurationOr("QTRANSFER_MONITOR_INTERVAL", 5*time.Minute), "Monitor polling interval (e.g. 2m, 30s)")
+	flag.StringVar(&cfg.SyncMode, "sync-mode", strings.ToLower(envOr("QTRANSFER_SYNC_MODE", "append")), "Sync mode for monitor-transfer: append or mirror")
+	flag.Int64Var(&cfg.TargetPlaylistID, "target-playlist-id", envInt64Or("QTRANSFER_TARGET_PLAYLIST_ID", 0), "Bind source playlist (single URL only) to existing Qobuz playlist ID")
 
 	flag.BoolVar(&cfg.DryRun, "dry-run", envBoolOr("QTRANSFER_DRY_RUN", false), "Resolve matches only, do not create or mutate Qobuz playlists")
 	flag.StringVar(&cfg.ReportPath, "report", envOr("QTRANSFER_REPORT", "transfer-report.json"), "Report output path")
@@ -119,6 +125,8 @@ func Load() (Config, error) {
 	cfg.PlaylistNames = playlists
 	cfg.PlaylistURLs = playlistURLs
 	cfg.SpotifyScopes = splitComma(*scopes)
+	cfg.SyncMode = strings.ToLower(strings.TrimSpace(cfg.SyncMode))
+	cfg.SyncMode = strings.ToLower(strings.TrimSpace(cfg.SyncMode))
 
 	if err := cfg.Validate(); err != nil {
 		return Config{}, err
@@ -144,6 +152,15 @@ func (c Config) Validate() error {
 	if c.MonitorInterval < 2*time.Second {
 		return fmt.Errorf("monitor interval must be at least 2s")
 	}
+	if c.SyncMode != "append" && c.SyncMode != "mirror" {
+		return fmt.Errorf("invalid sync mode %q (expected append or mirror)", c.SyncMode)
+	}
+	if c.TargetPlaylistID < 0 {
+		return fmt.Errorf("target-playlist-id must be >= 0")
+	}
+	if c.TargetPlaylistID > 0 && !c.Monitor {
+		return fmt.Errorf("target-playlist-id is currently supported with --monitor mode")
+	}
 	if strings.TrimSpace(c.SessionPath) == "" {
 		return fmt.Errorf("session file path cannot be empty")
 	}
@@ -192,6 +209,18 @@ func envIntOr(key string, fallback int) int {
 	return n
 }
 
+func envInt64Or(key string, fallback int64) int64 {
+	v := strings.TrimSpace(os.Getenv(key))
+	if v == "" {
+		return fallback
+	}
+	n, err := strconv.ParseInt(v, 10, 64)
+	if err != nil {
+		return fallback
+	}
+	return n
+}
+
 func envBoolOr(key string, fallback bool) bool {
 	v := strings.TrimSpace(os.Getenv(key))
 	if v == "" {

internal/jobconfig/config.go

@@ -0,0 +1,76 @@
+package jobconfig
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/BurntSushi/toml"
+)
+
+type File struct {
+	Global    GlobalConfig    `toml:"global"`
+	Playlists []PlaylistEntry `toml:"playlist"`
+}
+
+type GlobalConfig struct {
+	Monitor         *bool  `toml:"monitor"`
+	MonitorOnce     *bool  `toml:"monitor_once"`
+	MonitorTransfer *bool  `toml:"monitor_transfer"`
+	MonitorInterval string `toml:"monitor_interval"`
+	SyncMode        string `toml:"sync_mode"`
+	IncludeLiked    *bool  `toml:"include_liked"`
+	DryRun          *bool  `toml:"dry_run"`
+	PublicPlaylists *bool  `toml:"public_playlists"`
+	Concurrency     *int   `toml:"concurrency"`
+	ReportPath      string `toml:"report"`
+}
+
+type PlaylistEntry struct {
+	URL              string `toml:"url"`
+	SyncMode         string `toml:"sync_mode"`
+	TargetPlaylistID int64  `toml:"target_playlist_id"`
+	Enabled          *bool  `toml:"enabled"`
+}
+
+func Load(path string) (File, error) {
+	var cfg File
+	if strings.TrimSpace(path) == "" {
+		return cfg, fmt.Errorf("empty config path")
+	}
+
+	b, err := os.ReadFile(path)
+	if err != nil {
+		return cfg, err
+	}
+
+	if err := toml.Unmarshal(b, &cfg); err != nil {
+		return cfg, fmt.Errorf("parse toml config: %w", err)
+	}
+
+	for i, p := range cfg.Playlists {
+		if strings.TrimSpace(p.URL) == "" {
+			return cfg, fmt.Errorf("playlist entry %d missing url", i+1)
+		}
+		mode := strings.ToLower(strings.TrimSpace(p.SyncMode))
+		if mode != "" && mode != "append" && mode != "mirror" {
+			return cfg, fmt.Errorf("playlist entry %d has invalid sync_mode %q", i+1, p.SyncMode)
+		}
+		if p.TargetPlaylistID < 0 {
+			return cfg, fmt.Errorf("playlist entry %d has invalid target_playlist_id %d", i+1, p.TargetPlaylistID)
+		}
+	}
+
+	if mode := strings.ToLower(strings.TrimSpace(cfg.Global.SyncMode)); mode != "" && mode != "append" && mode != "mirror" {
+		return cfg, fmt.Errorf("invalid global sync_mode %q", cfg.Global.SyncMode)
+	}
+
+	return cfg, nil
+}
+
+func (p PlaylistEntry) IsEnabled() bool {
+	if p.Enabled == nil {
+		return true
+	}
+	return *p.Enabled
+}

internal/qobuz/client.go

@@ -5,6 +5,7 @@ import (
 	"crypto/md5"
 	"encoding/hex"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -39,6 +40,8 @@ type Track struct {
 	Album    string
 }
 
+var ErrDuplicateTracks = errors.New("qobuz duplicate tracks")
+
 func NewClient(appID, appSecret string) *Client {
 	return &Client{
 		httpClient: &http.Client{Timeout: 30 * time.Second},
@@ -197,6 +200,7 @@ func (c *Client) AddTracksToPlaylist(ctx context.Context, playlistID int64, trac
 	if len(trackIDs) == 0 {
 		return nil
 	}
+	hadDuplicate := false
 	chunks := chunk(trackIDs, 100)
 	for _, ch := range chunks {
 		ids := make([]string, 0, len(ch))
@@ -210,9 +214,16 @@ func (c *Client) AddTracksToPlaylist(ctx context.Context, playlistID int64, trac
 
 		var out map[string]any
 		if err := c.postFormSigned(ctx, "/playlist/addTracks", form, &out); err != nil {
+			if isDuplicateConflictErr(err) {
+				hadDuplicate = true
+				continue
+			}
 			return err
 		}
 	}
+	if hadDuplicate {
+		return ErrDuplicateTracks
+	}
 	return nil
 }
 
@@ -366,6 +377,17 @@ func isSigError(err error) bool {
 	return strings.Contains(msg, "signature") || strings.Contains(msg, "request_sig")
 }
 
+func isDuplicateConflictErr(err error) bool {
+	if err == nil {
+		return false
+	}
+	msg := strings.ToLower(err.Error())
+	if !strings.Contains(msg, "duplicate track") {
+		return false
+	}
+	return strings.Contains(msg, "(409)") || strings.Contains(msg, `"code":409`) || strings.Contains(msg, "code: 409")
+}
+
 func md5Hex(s string) string {
 	h := md5.Sum([]byte(s))
 	return hex.EncodeToString(h[:])

internal/session/session.go

@@ -13,6 +13,7 @@ type Data struct {
 	Spotify   SpotifyState               `json:"spotify"`
 	Qobuz     QobuzState                 `json:"qobuz"`
 	Monitor   map[string]string          `json:"monitor"`
+	Playlists map[string]PlaylistSyncRef `json:"playlists"`
 	Meta      map[string]string          `json:"meta,omitempty"`
 }
 
@@ -30,6 +31,12 @@ type QobuzState struct {
 	AccessToken string `json:"access_token,omitempty"`
 }
 
+type PlaylistSyncRef struct {
+	SourceName      string `json:"source_name,omitempty"`
+	QobuzPlaylistID int64  `json:"qobuz_playlist_id,omitempty"`
+	Fingerprint     string `json:"fingerprint,omitempty"`
+}
+
 func DefaultPath() string {
 	home, err := os.UserHomeDir()
 	if err != nil || strings.TrimSpace(home) == "" {
@@ -72,6 +79,9 @@ func Load(path string) (Data, error) {
 	if d.Monitor == nil {
 		d.Monitor = map[string]string{}
 	}
+	if d.Playlists == nil {
+		d.Playlists = map[string]PlaylistSyncRef{}
+	}
 	return d, nil
 }