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mandelstudio/mandelstudio/i18n_utils.py

38 lines
1.1 KiB
Python

from __future__ import annotations
import re
from urllib.parse import urlsplit, urlunsplit
from django.conf import settings
def normalize_set_language_next(value: str | None) -> str:
"""
Normalize the `next` path used by Django's set_language view.
Removes any leading language prefix from the path so switching from one
locale to another cannot produce duplicated prefixes like `/de/en/...`.
"""
if not value:
return "/"
parsed = urlsplit(str(value))
path = parsed.path or "/"
if not path.startswith("/"):
path = f"/{path}"
configured_codes = {
str(code).lower().replace("_", "-") for code, _ in settings.LANGUAGES
}
first_segment, _, remainder = path.lstrip("/").partition("/")
normalized_segment = first_segment.lower().replace("_", "-")
looks_like_language_code = bool(
re.fullmatch(r"[a-z]{2}(?:-[a-z]{2})?", normalized_segment)
)
should_strip = normalized_segment in configured_codes or looks_like_language_code
if should_strip:
path = f"/{remainder}" if remainder else "/"
return urlunsplit(("", "", path, parsed.query, ""))