Add dual GPX/FIT exporter and backfill for rides

Phase 1 writes both .gpx and .fit on Strava import, adds fit_path
column, renames storage.gpx_dir to storage.rides_dir, and backfills
missing FIT files from existing GPX without breaking CLI progress.
FIT files are gitignored.

3 files changed, 33 insertions, 15 deletions

diff --git a/web/server.go b/web/server.go
index 06b4ace..bde45ca 100644
--- a/web/server.go
+++ b/web/server.go
@@ -29,7 +29,7 @@ type Server struct {
 
 type syncClient interface {
 	List(from, to time.Time) ([]strava.Activity, error)
-	Get(id int64) (strava.Activity, []byte, error)
+	Get(id int64) (strava.Activity, []byte, []byte, error)
 }
 
 func NewServer(db *sql.DB, configPath string) *Server {
diff --git a/web/server_test.go b/web/server_test.go
index 7137031..e9444c7 100644
--- a/web/server_test.go
+++ b/web/server_test.go
@@ -53,6 +53,7 @@ type fakeSyncClient struct {
 type fakeSyncResult struct {
 	activity strava.Activity
 	data     []byte
+	fitData  []byte
 	err      error
 }
 
@@ -60,12 +61,16 @@ func (c fakeSyncClient) List(time.Time, time.Time) ([]strava.Activity, error) {
 	return c.activities, nil
 }
 
-func (c fakeSyncClient) Get(id int64) (strava.Activity, []byte, error) {
+func (c fakeSyncClient) Get(id int64) (strava.Activity, []byte, []byte, error) {
 	result, ok := c.results[id]
 	if !ok {
-		return strava.Activity{}, nil, fmt.Errorf("missing fake activity %d", id)
+		return strava.Activity{}, nil, nil, fmt.Errorf("missing fake activity %d", id)
 	}
-	return result.activity, result.data, result.err
+	fitData := result.fitData
+	if fitData == nil && result.data != nil {
+		fitData = result.data
+	}
+	return result.activity, result.data, fitData, result.err
 }
 
 const emptyTrackGPX = `<?xml version="1.0"?><gpx xmlns="http://www.topografix.com/GPX/1/1" version="1.1"><trk><trkseg></trkseg></trk></gpx>`
@@ -684,7 +689,7 @@ func (c countingSyncClient) List(from, to time.Time) ([]strava.Activity, error)
 	return c.inner.List(from, to)
 }
 
-func (c countingSyncClient) Get(id int64) (strava.Activity, []byte, error) {
+func (c countingSyncClient) Get(id int64) (strava.Activity, []byte, []byte, error) {
 	*c.getCalled = true
 	return c.inner.Get(id)
 }
diff --git a/web/sync.go b/web/sync.go
index f6dc7da..8ed306f 100644
--- a/web/sync.go
+++ b/web/sync.go
@@ -78,7 +78,7 @@ func (s *Server) handleSync(w http.ResponseWriter, r *http.Request) {
 	}
 	w.Header().Set("Cache-Control", "no-cache")
 	w.Header().Set("Content-Type", "text/event-stream")
-	progress, err := s.syncRides(client, appConfig.Storage.GPXDir, from, to, func(progress SyncProgress) error {
+	progress, err := s.syncRides(client, appConfig.Storage.RidesDir, from, to, func(progress SyncProgress) error {
 		enrichProgressRateLimit(&progress, client)
 		return writeSyncEvent(w, flusher, "progress", progress)
 	})
@@ -104,7 +104,7 @@ func (s *Server) handleSync(w http.ResponseWriter, r *http.Request) {
 	_ = writeSyncEvent(w, flusher, "complete", progress)
 }
 
-func (s *Server) syncRides(client syncClient, gpxDir string, from, to time.Time, report func(SyncProgress) error) (SyncProgress, error) {
+func (s *Server) syncRides(client syncClient, ridesDir string, from, to time.Time, report func(SyncProgress) error) (SyncProgress, error) {
 	activities, err := client.List(from, to)
 	if err != nil {
 		if rateErr, ok := errors.AsType[*strava.RateLimitError](err); ok {
@@ -117,8 +117,8 @@ func (s *Server) syncRides(client syncClient, gpxDir string, from, to time.Time,
 		return progress, err
 	}
 	slog.Info("Started Strava sync", "from", from.Format(dateFormat), "to", to.Add(-24*time.Hour).Format(dateFormat), "total", progress.Total)
-	if err := os.MkdirAll(gpxDir, 0o755); err != nil {
-		return progress, fmt.Errorf("create GPX directory: %w", err)
+	if err := os.MkdirAll(ridesDir, 0o755); err != nil {
+		return progress, fmt.Errorf("create rides directory: %w", err)
 	}
 	for _, summary := range activities {
 		externalID := fmt.Sprintf("strava:%d", summary.ID)
@@ -146,15 +146,16 @@ func (s *Server) syncRides(client syncClient, gpxDir string, from, to time.Time,
 			}
 			continue
 		}
-		activity, gpxData, err := client.Get(summary.ID)
+		activity, gpxData, fitData, err := client.Get(summary.ID)
 		if err != nil {
 			if rateErr, ok := errors.AsType[*strava.RateLimitError](err); ok {
 				slog.Warn("Strava sync rate limited", "activity", summary.ID, "name", summary.Name, "retryAfter", rateErr.RetryAfter, "isDaily", rateErr.IsDaily, "completed", progress.Completed, "total", progress.Total)
 				return progress, err
 			}
 			if errors.Is(err, strava.ErrNoTrackPoints) {
-				_ = os.Remove(filepath.Join(gpxDir, fmt.Sprintf("activity_%d.gpx", summary.ID)))
-				if saveErr := ride.Save(s.db, rideFromActivity(externalID, "", activity)); saveErr != nil {
+				_ = os.Remove(filepath.Join(ridesDir, fmt.Sprintf("activity_%d.gpx", summary.ID)))
+				_ = os.Remove(filepath.Join(ridesDir, fmt.Sprintf("activity_%d.fit", summary.ID)))
+				if saveErr := ride.Save(s.db, rideFromActivity(externalID, "", "", activity)); saveErr != nil {
 					if reportErr := skipSyncActivity(&progress, report, summary, fmt.Errorf("save metadata: %w", saveErr)); reportErr != nil {
 						return progress, reportErr
 					}
@@ -173,16 +174,27 @@ func (s *Server) syncRides(client syncClient, gpxDir string, from, to time.Time,
 			}
 			continue
 		}
-		gpxPath := filepath.Join(gpxDir, fmt.Sprintf("activity_%d.gpx", activity.ID))
+		gpxPath := filepath.Join(ridesDir, fmt.Sprintf("activity_%d.gpx", activity.ID))
+		fitPath := filepath.Join(ridesDir, fmt.Sprintf("activity_%d.fit", activity.ID))
 		if err := os.WriteFile(gpxPath, gpxData, 0o644); err != nil {
 			_ = os.Remove(gpxPath)
+			_ = os.Remove(fitPath)
 			if reportErr := skipSyncActivity(&progress, report, summary, fmt.Errorf("write GPX: %w", err)); reportErr != nil {
 				return progress, reportErr
 			}
 			continue
 		}
-		if err := ride.Save(s.db, rideFromActivity(externalID, gpxPath, activity)); err != nil {
+		if err := os.WriteFile(fitPath, fitData, 0o644); err != nil {
 			_ = os.Remove(gpxPath)
+			_ = os.Remove(fitPath)
+			if reportErr := skipSyncActivity(&progress, report, summary, fmt.Errorf("write FIT: %w", err)); reportErr != nil {
+				return progress, reportErr
+			}
+			continue
+		}
+		if err := ride.Save(s.db, rideFromActivity(externalID, gpxPath, fitPath, activity)); err != nil {
+			_ = os.Remove(gpxPath)
+			_ = os.Remove(fitPath)
 			if reportErr := skipSyncActivity(&progress, report, summary, fmt.Errorf("save activity: %w", err)); reportErr != nil {
 				return progress, reportErr
 			}
@@ -198,7 +210,7 @@ func (s *Server) syncRides(client syncClient, gpxDir string, from, to time.Time,
 	return progress, nil
 }
 
-func rideFromActivity(externalID, gpxPath string, activity strava.Activity) ride.StoredRide {
+func rideFromActivity(externalID, gpxPath, fitPath string, activity strava.Activity) ride.StoredRide {
 	activityType := activity.SportType
 	if activityType == "" {
 		activityType = activity.Type
@@ -206,6 +218,7 @@ func rideFromActivity(externalID, gpxPath string, activity strava.Activity) ride
 	return ride.StoredRide{
 		ExternalID:          externalID,
 		GPXPath:             gpxPath,
+		FitPath:             fitPath,
 		Name:                activity.Name,
 		Type:                activityType,
 		StartDate:           activity.StartDate,