@@ -126,10 +126,14 @@ def watch_windows(sock, changes, handle):

             handle(sock, {'id': window, **container['window_properties']})

         for node in nodes:

             recurse(node)

+    # TODO: Race? Subscribe first, handle the `MSG_GET_TREE` response in the

+    # `while True`. This is our only use of `sync_reply`, so we could get rid

+    # of that if we want.

     recurse(send(sock, MSG_GET_TREE, sync_reply=True))

     send(sock, MSG_SUBSCRIBE, ['window', 'shutdown'])

     while True:

         tag, msg = recv(sock)

+        # TODO: `match`/`case`, requires newer Python.

         if tag == MSG_SUBSCRIBE:

             assert msg['success']

         elif tag == MSG_COMMAND:

@@ -147,6 +151,7 @@ def replace(sock, props):

     command(sock, '[id={id}] title_format "{title}"'.format(**props))

 def restore(sock):

+    # TODO: `[all]`, requires newer `i3`.

     command(sock, '[title=".*"] title_format "%title"')

 ## Main

new file mode 100755

@@ -0,0 +1,179 @@

+#!/usr/bin/env python3

+

+"""

+Many applications put a delimiter and their name as a suffix in the window

+title. Try to make it a lowercase prefix instead, with another delimiter, after

+decluttering by removing everything but the executable name. We use different

+dashes to detect delimiters, and executables in `PATH` as a heuristic to detect

+names. We also detect when window titles already conform to our preferred

+format, probably because the application was manually configured. Note that it

+still has false positives. Also, this is maybe better done by modifying the

+actual X11 window name.

+

+Uses only the Python standard library.

+

+References:

+

+-   <https://i3wm.org/docs/ipc.html>

+-   <https://docs.python.org/3/library/struct.html#byte-order-size-and-alignment>

+-   <https://docs.python.org/3/library/struct.html#format-characters>

+-   <https://i3wm.org/docs/userguide.html#pango_markup>

+-   <https://docs.gtk.org/Pango/pango_markup.html>

+-   <https://docs.gtk.org/glib/func.markup_escape_text.html>

+

+You can run these tests with `i3-rename-windows --test`:

+

+>>> rename('Some video - VLC media player')

+'vlc:Some video'

+

+>>> rename('Some website — Mozilla Firefox')

+'firefox:Some website'

+

+>>> rename('Mozilla Firefox')

+'firefox'

+

+>>> rename('Some other - Some unkown')

+'Some other - Some unkown'

+

+>>> rename('vim:the best editor - vim of course.txt')

+'vim:the best editor - vim of course.txt'

+"""

+

+## Rename

+

+import os

+import re

+

+SEP  = ':'

+SEPS = '-–—'

+EXES = '|'.join(

+    re.escape(file)

+    for path in os.environ.get('PATH', os.defpath).split(os.pathsep)

+    for file in os.listdir(path)

+    if os.access(os.path.join(path, file), os.F_OK | os.X_OK)

+)

+REGEX = re.compile(

+    fr'^'

+    fr'(?!(?:{EXES}){SEP}[^ ])'

+    fr'(?:(?P<name>.*) +[{SEPS}] +)?'

+    fr'.*'

+    fr'(?P<exe>\b(?i:{EXES})\b)'

+    fr'.*'

+    fr'$'

+)

+

+def rename(name):

+    match = re.match(REGEX, name)

+    if match:

+        return SEP.join(filter(None, [

+            match['exe'].lower(),

+            match['name'],

+        ]))

+    return name

+

+## Serialization

+

+import json

+import struct

+

+MAGIC   = b'i3-ipc'

+HDR_FMT = '=LL'

+HDR_LEN = struct.calcsize(HDR_FMT)

+ESCAPE  = [

+    ['\\', '\\\\' ],

+    ['"',  '\\"'  ],

+    ['&',  '&'],

+    ['<',  '&lt;' ],

+    ['>',  '>' ],

+    ['%',  '%'],

+]

+

+def recv(sock):

+    assert sock.recv(len(MAGIC)) == MAGIC

+    payload_len, tag = struct.unpack(HDR_FMT, sock.recv(HDR_LEN))

+    return tag, json.loads(sock.recv(payload_len))

+

+def send(sock, tag, msg=b'', sync_reply=False):

+    payload = msg if type(msg) is bytes else json.dumps(msg).encode()

+    header  = struct.pack(HDR_FMT, len(payload), tag)

+    sock.sendall(MAGIC + header + payload)

+    if sync_reply:

+        reply_tag, reply_msg = recv(sock)

+        assert reply_tag == tag

+        return reply_msg

+

+def escape(string):

+    for old, new in ESCAPE:

+        string = string.replace(old, new)

+    return string

+

+## Messages

+

+MSG_COMMAND   = 0

+MSG_SUBSCRIBE = 2

+MSG_GET_TREE  = 4

+EVT_WINDOW    = 3 | 1 << 31

+EVT_SHUTDOWN  = 6 | 1 << 31

+

+def command(sock, command):

+    send(sock, MSG_COMMAND, command.encode())

+

+def watch_windows(sock, changes, handle):

+    def recurse(container):

+        window = container['window']

+        nodes  = container['nodes']

+        if window:

+            handle(sock, {'id': window, **container['window_properties']})

+        for node in nodes:

+            recurse(node)

+    recurse(send(sock, MSG_GET_TREE, sync_reply=True))

+    send(sock, MSG_SUBSCRIBE, ['window', 'shutdown'])

+    while True:

+        tag, msg = recv(sock)

+        if tag == MSG_SUBSCRIBE:

+            assert msg['success']

+        elif tag == MSG_COMMAND:

+            assert all(r['success'] for r in msg)

+        elif tag == EVT_WINDOW:

+            if msg['change'] in changes:

+                recurse(msg['container'])

+        elif tag == EVT_SHUTDOWN:

+            return msg['change'] == 'restart'

+

+## Titles

+

+def replace(sock, props):

+    props['title'] = escape(rename(props['title']))

+    command(sock, '[id={id}] title_format "{title}"'.format(**props))

+

+def restore(sock):

+    command(sock, '[title=".*"] title_format "%title"')

+

+## Main

+

+import subprocess

+import socket

+

+def run(*args):

+    return subprocess.check_output(args, text=True).strip()

+

+def main():

+    while True:

+        with socket.socket(socket.AF_UNIX) as sock:

+            sock.connect(run('i3', '--get-socket'))

+            try:

+                if not watch_windows(sock, ['new', 'title'], replace):

+                    break

+            except KeyboardInterrupt:

+                break

+            finally:

+                restore(sock)

+                sock.shutdown(socket.SHUT_RDWR)

+

+if __name__ == '__main__':

+    import sys

+    args = iter(sys.argv[1:])

+    if next(args, None) == '--test':

+        import doctest

+        exit(doctest.testmod().failed != 0)

+    main()