From 999a173001e8b687d17a135f0f9d6b795ffb88f3 Mon Sep 17 00:00:00 2001
From: Colin <colin@uninsane.org>
Date: Thu, 13 Jun 2024 08:22:57 +0000
Subject: [PATCH] sane-tag-music: `--trackno "" fix-tags FOO` can be used to
 clear FOOs track number field

---
 .../additional/sane-scripts/src/sane-tag-music | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/pkgs/additional/sane-scripts/src/sane-tag-music b/pkgs/additional/sane-scripts/src/sane-tag-music
index 4edc7d3c..75a35ae3 100755
--- a/pkgs/additional/sane-scripts/src/sane-tag-music
+++ b/pkgs/additional/sane-scripts/src/sane-tag-music
@@ -22,8 +22,8 @@ then this updates the tags on-disk to reflect their path.
 DIRECTORY: specify `.` to scan the entire library.
 
 options:
---dry-run: only show what would be done, don't actually do it.
---verbose
+  --dry-run: only show what would be done, don't actually do it.
+  --verbose
   --album ALBUM           manually specify the tag, rather than guessing from path.
   --album-artist ARTIST   often combined with DIRECTORY to tag an entire artist or album.
   --artist ARTIST
@@ -31,7 +31,7 @@ options:
   --trackno TRACK_NUMBER
 
 fix-tags options:
---force: apply path-based tag to each file, even those which already have tags (only for fix-tags)
+  --force: apply path-based tag to each file, even those which already have tags (only for fix-tags)
 """
 
 from dataclasses import dataclass
@@ -118,6 +118,10 @@ class Tags:
         return f"artist:{self.artist}/{self.albumartist}, album:{self.album}, title:{self.title}, trackno:{self.tracknumber}"
 
     def union(self, fallback: 'Tags') -> 'Tags':
+        """
+        substitute any tags missing tags in `self` with those from `fallback`.
+        i.e. `self` takes precedence over `fallback`.
+        """
         def merge_field(primary: list[str], secondary: list[str]) -> list[str]:
             # primary_lower = [i.lower() for i in primary]
             # return primary + [i for i in secondary if i.lower() not in primary_lower]
@@ -159,6 +163,9 @@ class Tags:
             if v.count("/") == 1:
                 trackno, last = v.split("/")
                 try:
+                    if int(trackno) == int(last) == 1:
+                        # track 1/1: useless; clear the field
+                        self.tracknumber[i] = ''
                     if int(trackno) <= int(last):
                         self.tracknumber[i] = trackno.lstrip('0')
                 except: pass
@@ -401,9 +408,14 @@ class Tagger:
         path_tags = Tags.from_path(path_)
         additional_tags = self.manual_tags.union(path_tags)
         if self.force:
+            # additional_tags overrule old_tags
             new_tags = additional_tags.union(old_tags)
         else:
+            # old_tags overrule additional_tags
             new_tags = old_tags.union(additional_tags)
+            if additional_tags.tracknumber == [""]:
+                # special case that `--trackno ""` can be used to delete the track number without `--force`ing all fields
+                new_tags.tracknumber = []
         new_tags = new_tags.union(self.manual_tags)
         new_tags.trim_fields()
         new_tags.cleanup_trackno()