kakoune go to link in markdown

kak/filetypes/markdown.kak

@@ -1,6 +1,15 @@
+define-command -hidden -override md-follow-link \
+-docstring 'Folge dem Markdown-/Hugo-Link unter dem Cursor' %{
+    evaluate-commands %sh{
+        python3 "$kak_config/scripts/hugo-link.py" \
+            "$kak_buffile" "$kak_cursor_line" "$kak_cursor_column"
+    }
+}
+
 define-command -hidden -override filetype-markdown %{
     set-option window tabstop 2
     set-option window indentwidth 2
+    map window goto d '<esc>: md-follow-link<ret>' -docstring 'Link folgen'
 }
 
 hook global WinSetOption filetype=markdown %{ filetype-markdown }

kak/scripts/hugo-link.py

@@ -0,0 +1,130 @@
+#!/usr/bin/env python3
+"""Folge dem Markdown-/Hugo-internen Link unter dem Cursor.
+
+Aufruf:  hugo-link.py <buffile> <cursor_line> <cursor_column>
+
+Gibt auf stdout genau ein Kakoune-Kommando aus:
+  * edit -existing '<pfad>'   -> Zieldatei oeffnen
+  * nop %sh{ xdg-open ... }   -> externe URL im Browser
+  * echo -markup '{Error}..'  -> nichts gefunden / Fehler
+"""
+import os
+import re
+import shlex
+import sys
+
+
+def kak_str(s):
+    """String fuer Kakoune in einfachen Anfuehrungszeichen quoten."""
+    return "'" + s.replace("'", "''") + "'"
+
+
+def emit_and_exit(cmd):
+    print(cmd)
+    sys.exit(0)
+
+
+def fail(msg):
+    emit_and_exit("echo -markup " + kak_str("{Error}" + msg))
+
+
+CONFIG_NAMES = (
+    "hugo.toml", "hugo.yaml", "hugo.yml", "hugo.json",
+    "config.toml", "config.yaml", "config.yml", "config.json",
+)
+
+# [text](ziel "optionaler Titel")  bzw.  [text](<ziel>)
+LINK_RE = re.compile(r'\[[^\]]*\]\(\s*<?([^)>\s]+)>?(?:\s+"[^"]*")?\s*\)')
+# <https://...>  Autolink
+AUTOLINK_RE = re.compile(r'<([a-zA-Z][\w+.-]*:[^>\s]+)>')
+
+
+def find_site_root(start):
+    d = start
+    while True:
+        if any(os.path.exists(os.path.join(d, n)) for n in CONFIG_NAMES):
+            return d
+        if os.path.isdir(os.path.join(d, "content")):
+            return d
+        parent = os.path.dirname(d)
+        if parent == d:
+            return None
+        d = parent
+
+
+def target_under_cursor(line, idx):
+    for regex in (LINK_RE, AUTOLINK_RE):
+        for m in regex.finditer(line):
+            if m.start() <= idx < m.end():
+                return m.group(1)
+    return None
+
+
+def open_external(target):
+    emit_and_exit("nop %%sh{ setsid xdg-open %s >/dev/null 2>&1 & }"
+                  % shlex.quote(target))
+
+
+def main():
+    if len(sys.argv) != 4:
+        fail("interner Aufruffehler")
+    buffile, line_s, col_s = sys.argv[1], sys.argv[2], sys.argv[3]
+    line_no, col = int(line_s), int(col_s)
+
+    try:
+        with open(buffile, encoding="utf-8") as fh:
+            lines = fh.read().split("\n")
+    except OSError as exc:
+        fail("kann Buffer nicht lesen: %s" % exc)
+
+    if not 1 <= line_no <= len(lines):
+        fail("Cursor ausserhalb des Buffers")
+    line = lines[line_no - 1]
+
+    target = target_under_cursor(line, col - 1)
+    if target is None:
+        fail("kein Link unter dem Cursor")
+
+    # Fragment (#...) und Query (?...) abtrennen
+    target = re.split(r'[#?]', target, maxsplit=1)[0]
+    if not target:
+        fail("Link zeigt nur auf einen Anker")
+
+    if (re.match(r'^[a-zA-Z][a-zA-Z0-9+.-]*://', target)
+            or target.startswith("//")
+            or target.startswith("mailto:")):
+        open_external(target)
+
+    buf_dir = os.path.dirname(os.path.abspath(buffile))
+
+    if target.startswith("/"):
+        root = find_site_root(buf_dir)
+        if root is None:
+            fail("kein Hugo-Root (hugo.toml / config.*) oberhalb gefunden")
+        content_dir = os.path.join(root, "content")
+        if not os.path.isdir(content_dir):
+            content_dir = root
+        base = os.path.normpath(
+            os.path.join(content_dir, target.lstrip("/")))
+    else:
+        base = os.path.normpath(os.path.join(buf_dir, target))
+
+    if base.endswith(".md"):
+        candidates = [base]
+    else:
+        candidates = [
+            base + ".md",
+            os.path.join(base, "_index.md"),
+            os.path.join(base, "index.md"),
+            base,  # z.B. direkt verlinktes Bild / statische Datei
+        ]
+
+    for cand in candidates:
+        if os.path.isfile(cand):
+            emit_and_exit("edit -existing " + kak_str(cand))
+
+    fail("Ziel nicht gefunden: " + " | ".join(candidates))
+
+
+if __name__ == "__main__":
+    main()