New script lossage.py: displays the last few input keystrokes and the commands run

Author: GermainZ

python/lossage.py

@@ -0,0 +1,158 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2021 Germain Z. <[email protected]>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#
+# Inspired by Emacs's view-lossage, this script displays a history of the last
+# keystrokes you performed and the commands invoked.
+#
+
+
+import collections
+import dataclasses
+import re
+from typing import Deque, Dict, Iterable, Tuple
+
+import weechat  # type: ignore # pylint: disable=import-error
+
+
+SCRIPT_NAME = "lossage"
+SCRIPT_AUTHOR = "GermainZ <[email protected]>"
+SCRIPT_VERSION = "0.1"
+SCRIPT_LICENSE = "GPL3"
+SCRIPT_DESC = (
+    "Displays the last few input keystrokes and the commands run, "
+    "inspired by Emacs's view-lossage."
+)
+
+
+HISTORY_SIZE: int = 300
+REGEX_COMBO_REPL: Iterable[Tuple[re.Pattern, str]] = (
+    (re.compile(r"\x01\[\["), "meta2-"),
+    (re.compile(r"\x01\["), "meta-"),
+    (re.compile(r"\x01"), "ctrl-"),
+)
+REGEX_AREA_STRIP = re.compile(r"^@[^:]+:")
+HEADER: Tuple[str, str, str] = ("context", "combo", "command")
+
+
+@dataclasses.dataclass
+class HistoryItem:
+    context: str
+    combo: str
+    command: str
+
+
+@dataclasses.dataclass
+class Data:
+    history: Deque[HistoryItem] = dataclasses.field(
+        default_factory=lambda: collections.deque(maxlen=HISTORY_SIZE)
+    )
+    key_bindings: Dict[str, Dict[str, str]] = dataclasses.field(
+        default_factory=lambda: collections.defaultdict(dict)
+    )
+
+
+DATA = Data()
+
+
+def cb_key_combo(context: str, signal: str, signal_data: str):
+    mode = signal.split("_")[-1]
+    combo = signal_data
+
+    for regex, repl in REGEX_COMBO_REPL:
+        combo = regex.sub(repl, combo)
+
+    command = DATA.key_bindings[context].get(combo, "")
+    DATA.history.append(HistoryItem(mode, combo, command))
+    return weechat.WEECHAT_RC_OK
+
+
+def cb_lossage_cmd(*_):
+    buffer = weechat.buffer_search("python", SCRIPT_NAME)
+    if not buffer:
+        buffer = weechat.buffer_new(SCRIPT_NAME, "", "", "", "")
+        weechat.buffer_set(buffer, "localvar_set_no_log", "1")
+        weechat.buffer_set(buffer, "time_for_each_line", "0")
+        weechat.buffer_set(buffer, "nicklist", "0")
+    weechat.command(buffer, f"/buffer {SCRIPT_NAME}")
+    weechat.command(buffer, "/buffer clear")
+
+    weechat.prnt(
+        buffer,
+        f"{weechat.color('bold')}{HEADER[0]:10} {HEADER[1]:20} {HEADER[2]}",
+    )
+    for item in DATA.history:
+        if item is None:
+            break
+        weechat.prnt(
+            buffer, f"{item.context:10} {item.combo:20} {item.command}"
+        )
+
+    return weechat.WEECHAT_RC_OK
+
+
+def cb_key_bindings_changed(*_):
+    populate_key_bindings()
+
+
+def populate_key_bindings():
+    for context in ("default", "search", "cursor"):
+        infolist = weechat.infolist_get("key", "", context)
+
+        while weechat.infolist_next(infolist):
+            key = weechat.infolist_string(infolist, "key")
+            command = weechat.infolist_string(infolist, "command")
+
+            # In the cursor context, bindings of the form `@area:key` can be
+            # created. When the binding is used, the area is not passed to the
+            # key_combo_* signal, so the best we can do is print a helpful
+            # warning if there are several possible matches.
+            if context == "cursor":
+                key = REGEX_AREA_STRIP.sub("", key)
+                if DATA.key_bindings[context].get(key, None):
+                    command = (
+                        f"ambiguous; see `/key list {context}` -> "
+                        f"`@…:{key}` key bindings"
+                    )
+
+            DATA.key_bindings[context][key] = command
+
+        weechat.infolist_free(infolist)
+
+
+if __name__ == "__main__":
+    weechat.register(
+        SCRIPT_NAME,
+        SCRIPT_AUTHOR,
+        SCRIPT_VERSION,
+        SCRIPT_LICENSE,
+        SCRIPT_DESC,
+        "",
+        "",
+    )
+
+    populate_key_bindings()
+
+    weechat.hook_signal("key_combo_default", "cb_key_combo", "default")
+    weechat.hook_signal("key_combo_search", "cb_key_combo", "search")
+    weechat.hook_signal("key_combo_cursor", "cb_key_combo", "cursor")
+    weechat.hook_command(
+        "lossage", SCRIPT_DESC, "", "test", "", "cb_lossage_cmd", ""
+    )
+    weechat.hook_signal("key_bind", "cb_key_bindings_changed", "")
+    weechat.hook_signal("key_unbind", "cb_key_bindings_changed", "")