From 33b350a612aa80e1b2ab01e4f76cee6b76af66b1 Mon Sep 17 00:00:00 2001
From: Michael Krieger <phyre@phyre.me>
Date: Mon, 15 Sep 2025 18:50:47 -0400
Subject: [PATCH] Adds a zero_disc_if_single_disc to the zero plugin

Adds a zero_disc_number_if_single_disc boolean to the zero plugin for writing to files. Adds the logic that, if disctotal is set and there is only one disc in disctotal, that the disc is not set.

This keeps tags cleaner, only using disc on multi-disc albums. The disctotal is not touched, particularly as this is not usually displayed in most clients.

The field is removed only for writing the tags, but the disc number is maintained in the database to avoid breaking anything that may depend on a disc number or avoid possible loops or failed logic.
---
 beetsplug/zero.py     | 7 ++++++-
 docs/changelog.rst    | 3 +++
 docs/plugins/zero.rst | 2 ++
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/beetsplug/zero.py b/beetsplug/zero.py
index bce3b1a72..e65dd8286 100644
--- a/beetsplug/zero.py
+++ b/beetsplug/zero.py
@@ -41,6 +41,7 @@ class ZeroPlugin(BeetsPlugin):
                 "fields": [],
                 "keep_fields": [],
                 "update_database": False,
+                "zero_disc_if_single_disc": False,
             }
         )
 
@@ -123,8 +124,12 @@ class ZeroPlugin(BeetsPlugin):
         """
         fields_set = False
 
+        if "disc" in tags and self.config["zero_disc_if_single_disc"].get(bool) and item.disctotal == 1:
+            self._log.debug("disc: {.disc} -> None", item)
+            tags["disc"] = None
+
         if not self.fields_to_progs:
-            self._log.warning("no fields, nothing to do")
+            self._log.warning("no fields list to remove")
             return False
 
         for field, progs in self.fields_to_progs.items():
diff --git a/docs/changelog.rst b/docs/changelog.rst
index 4f32093fe..f5109a9b4 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -8,6 +8,9 @@ Unreleased
 ----------
 
 New features:
+* :doc:`plugins/zero`: Add new configuration option,
+  ``zero_disc_if_single_disc``, to allow zeroing the disc number on
+  write for single-disc albums. Defaults to False.
 
 Bug fixes:
 
diff --git a/docs/plugins/zero.rst b/docs/plugins/zero.rst
index 6ed9427d9..88903a389 100644
--- a/docs/plugins/zero.rst
+++ b/docs/plugins/zero.rst
@@ -31,6 +31,8 @@ to nullify and the conditions for nullifying them:
   ``keep_fields``---not both!
 - To conditionally filter a field, use ``field: [regexp, regexp]`` to specify
   regular expressions.
+- Set ``zero_disc_if_single_disc`` to ``True`` to zero the disc number field
+  only if the album contains a disctotal count and is a single disc.
 - By default this plugin only affects files' tags; the beets database is left
   unchanged. To update the tags in the database, set the ``update_database``
   option to true.