feat(library): DeleteTrackFile (rm file + tracks row, album/artist preserved)

internal/library/delete.go

@@ -0,0 +1,49 @@
+package library
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io/fs"
+	"os"
+
+	"github.com/jackc/pgx/v5"
+	"github.com/jackc/pgx/v5/pgtype"
+	"github.com/jackc/pgx/v5/pgxpool"
+
+	"git.fabledsword.com/bvandeusen/minstrel/internal/db/dbq"
+)
+
+// ErrTrackNotFound is returned when DeleteTrackFile is called with an id
+// that has no row in tracks.
+var ErrTrackNotFound = errors.New("library: track not found")
+
+// DeleteTrackFile removes a track file from disk and its row from the
+// tracks table. Album and artist rows are left untouched.
+//
+// Steps:
+//  1. Look up the track to get its file_path.
+//  2. Remove the file from disk. fs.ErrNotExist is OK — already gone.
+//  3. Delete the tracks row.
+//
+// Order matters: file first, then DB. If the file delete fails (permission,
+// I/O error), we leave the DB row alone so the admin can retry.
+func DeleteTrackFile(ctx context.Context, pool *pgxpool.Pool, trackID pgtype.UUID) error {
+	q := dbq.New(pool)
+	track, err := q.GetTrackByID(ctx, trackID)
+	if err != nil {
+		if errors.Is(err, pgx.ErrNoRows) {
+			return ErrTrackNotFound
+		}
+		return fmt.Errorf("get track: %w", err)
+	}
+
+	if err := os.Remove(track.FilePath); err != nil && !errors.Is(err, fs.ErrNotExist) {
+		return fmt.Errorf("remove file: %w", err)
+	}
+
+	if _, err := pool.Exec(ctx, "DELETE FROM tracks WHERE id = $1", trackID); err != nil {
+		return fmt.Errorf("delete row: %w", err)
+	}
+	return nil
+}