feat: make NAS self-build deployment canonical

am_deduper/cli.py

@@ -9,25 +9,32 @@ from .scanner import scan
 from .watcher import watch
 
 
+def _db_path(root: Path, explicit: Path | None) -> Path:
+    if explicit:
+        return explicit
+    if str(root).startswith("/music/"):
+        return Path("/data/dedupe.db")
+    return root / ".dedupe" / "dedupe.db"
+
+
 def main() -> None:
     parser = argparse.ArgumentParser(prog="am-deduper")
     sub = parser.add_subparsers(dest="cmd", required=True)
 
-    def add_common(sp):
+    for name in ("scan", "dedupe", "reconcile"):
+        sp = sub.add_parser(name)
         sp.add_argument("root", type=Path)
         sp.add_argument("--db", type=Path, default=None)
-        sp.add_argument("--dry-run", action="store_true", help="report actions without changing files")
+        if name != "scan":
+            sp.add_argument("--dry-run", action="store_true")
 
-    add_common(sub.add_parser("scan"))
-    add_common(sub.add_parser("dedupe"))
-    add_common(sub.add_parser("reconcile"))
-    watch_parser = sub.add_parser("watch")
-    watch_parser.add_argument("root", type=Path)
-    watch_parser.add_argument("--db", type=Path, default=None)
-    watch_parser.add_argument("--l2", action="store_true", help="enable acoustic matching in the watcher")
+    wp = sub.add_parser("watch")
+    wp.add_argument("root", type=Path)
+    wp.add_argument("--db", type=Path, default=None)
+    wp.add_argument("--l2", action="store_true", help="enable acoustic matching")
 
     args = parser.parse_args()
-    db = args.db or (Path("/data/dedupe.db") if args.cmd != "watch" and str(args.root).startswith("/music/") else args.root / ".dedupe" / "dedupe.db")
+    db = _db_path(args.root, args.db)
 
     if args.cmd == "watch":
         watch(args.root, db, l2=args.l2)