Source code for klea_utils.ui.linkify

#!/usr/bin/env python3
"""
Bare-URL linkification for markdown text

File: klea_utils/ui/linkify.py

Copyright 2026 Ankur Sinha
Author: Ankur Sinha <sanjay DOT ankur AT gmail DOT com>
"""

import logging
import re

from linkify_it import LinkifyIt

logger = logging.getLogger(__name__)

#: Existing ``[text](url)`` markdown links are left untouched; only bare
#: URLs between them are linkified.  ``[^)]*`` is greedy up to the first
#: ``)``, which also tolerates balanced parentheses inside the URL.
_MARKDOWN_LINK_RE = re.compile(r"\[[^\]]*\]\([^)]*\)")

#: URL detection engine.  Defaults enable "fuzzy" matching of bare domains
#: and emails in addition to explicit http(s):// URLs.
_LINKIFY = LinkifyIt()




def linkify_md(text: str) -> str:
    """Convert bare URLs in markdown *text* to ``[url](url)`` links.

    Existing ``[text](url)`` links are returned verbatim so they are not
    re-wrapped.  Callers pass the result to a markdown renderer, which
    turns the wrapped URLs into clickable anchors.

    :param text: Markdown source text
    :returns: Text with bare URLs wrapped as ``[url](url)``
    """
    result: list[str] = []
    last = 0
    for match in _MARKDOWN_LINK_RE.finditer(text):
        result.append(_linkify_plain(text[last : match.start()]))
        result.append(match.group(0))
        last = match.end()
    result.append(_linkify_plain(text[last:]))
    return "".join(result)



def _linkify_plain(text: str) -> str:
    """Wrap bare URLs in *text* (which contains no markdown links)."""
    if not text:
        return text
    matches = _LINKIFY.match(text)
    if not matches:
        return text
    result: list[str] = []
    last = 0
    for match in matches:
        result.append(text[last : match.index])
        result.append(f"[{match.text}]({match.url})")
        last = match.last_index
    result.append(text[last:])
    return "".join(result)