Files
beets/beetsplug/rewrite.py
Šarūnas Nejus 30ab81eb5b Extract UserError from beets.ui to a new beets.exceptions module.
Update all references in core, plugins, and tests to import UserError
from the new location. This centralizes exception handling and improves
code organization.
2026-05-16 11:18:51 +01:00

101 lines
3.3 KiB
Python

# This file is part of beets.
# Copyright 2016, Adrian Sampson.
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
"""Uses user-specified rewriting rules to canonicalize names for path
formats.
"""
import re
from collections import defaultdict
from functools import singledispatch
from typing import Any, TypeVar
from beets import library
from beets.exceptions import UserError
from beets.plugins import BeetsPlugin
T = TypeVar("T")
@singledispatch
def rewrite_value(value: Any, pat: re.Pattern[str], repl: str) -> Any:
"""Rewrite a value if it matches the given pattern."""
return value
@rewrite_value.register
def _(value: str, pat: re.Pattern[str], repl: str) -> str:
if pat.match(value.lower()):
return repl
return value
@rewrite_value.register(list)
def _(value: list[str], pat: re.Pattern[str], repl: str) -> list[str]:
return [rewrite_value(v, pat, repl) for v in value]
def apply_rewrite_rules(
value: T, rules: list[tuple[re.Pattern[str], str]]
) -> T:
"""Apply all matching rewrite rules to the given value."""
for pattern, replacement in rules:
value = rewrite_value(value, pattern, replacement)
return value
def rewriter(field, rules):
"""Create a template field function that rewrites the given field
with the given rewriting rules. ``rules`` must be a list of
(pattern, replacement) pairs.
"""
def fieldfunc(item):
return apply_rewrite_rules(item._values_fixed[field], rules)
return fieldfunc
class RewritePlugin(BeetsPlugin):
def __init__(self):
super().__init__()
self.config.add({})
# Gather all the rewrite rules for each field.
rules = defaultdict(list)
for key, view in self.config.items():
value = view.as_str()
try:
fieldname, pattern = key.split(None, 1)
except ValueError:
raise UserError("invalid rewrite specification")
if fieldname not in library.Item._fields:
raise UserError(f"invalid field name ({fieldname}) in rewriter")
self._log.debug("adding template field {}", key)
pattern = re.compile(pattern.lower())
rules[fieldname].append((pattern, value))
if fieldname == "artist":
# Special case for the artist field: apply the same
# rewrite for "albumartist" as well.
rules["albumartist"].append((pattern, value))
# Replace each template field with the new rewriter function.
for fieldname, fieldrules in rules.items():
getter = rewriter(fieldname, fieldrules)
self.template_fields[fieldname] = getter
if fieldname in library.Album._fields:
self.album_template_fields[fieldname] = getter