recurse if given path points to dir

symuid

@@ -3,6 +3,7 @@
 
 import mutagen
 import mutagen.id3
+import mutagen.mp4
 import os
 import subprocess
 
@@ -17,7 +18,7 @@ def generate_uuid():
 
 
 def get_uuid(id3_tags):
-    assert isinstance(id3_tags, mutagen.id3.ID3)
+    assert isinstance(id3_tags, mutagen.id3.ID3), type(id3_tags)
     ufids = id3_tags.getall('UFID')
     for ufid in ufids:
         if ufid.owner == TRACK_UUID_ID3_OWNER_ID:
@@ -41,15 +42,28 @@ def get_or_assign_uuid(id3_tags):
     return uuid
 
 
-def symuid(track_path):
-    f = mutagen.File(filename=track_path)
-    print(get_or_assign_uuid(f.tags))
+def symuid(path):
+    if os.path.isdir(path):
+        for dirpath, dirnames, filenames in os.walk(path):
+            for filename in filenames:
+                symuid(os.path.join(dirpath, filename))
+    else:
+        try:
+            f = mutagen.File(filename=path)
+        except Exception:
+            raise Exception(path)
+        if not f:
+            print("{!r}: unsupported filetype, ignored".format(path))
+        elif isinstance(f.tags, mutagen.mp4.MP4Tags):
+            print("{!r}: mp4 tags not supported, ignored".format(path))
+        else:
+            get_or_assign_uuid(f.tags)
 
 
 def _init_argparser():
     import argparse
     argparser = argparse.ArgumentParser(description=None)
-    argparser.add_argument('track_path')
+    argparser.add_argument('path')
     return argparser