qutebrowser/qutebrowser/keyinput/basekeyparser.py
2018-02-27 13:02:32 +01:00

238 lines
8.0 KiB
Python

# vim: ft=python fileencoding=utf-8 sts=4 sw=4 et:
# Copyright 2014-2018 Florian Bruhin (The Compiler) <mail@qutebrowser.org>
#
# This file is part of qutebrowser.
#
# qutebrowser 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.
#
# qutebrowser 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 qutebrowser. If not, see <http://www.gnu.org/licenses/>.
"""Base class for vim-like key sequence parser."""
from PyQt5.QtCore import pyqtSignal, QObject
from PyQt5.QtGui import QKeySequence
from qutebrowser.config import config
from qutebrowser.utils import usertypes, log, utils
from qutebrowser.keyinput import keyutils
class BaseKeyParser(QObject):
"""Parser for vim-like key sequences and shortcuts.
Not intended to be instantiated directly. Subclasses have to override
execute() to do whatever they want to.
Class Attributes:
Match: types of a match between a binding and the keystring.
partial: No keychain matched yet, but it's still possible in the
future.
definitive: Keychain matches exactly.
none: No more matches possible.
do_log: Whether to log keypresses or not.
passthrough: Whether unbound keys should be passed through with this
handler.
Attributes:
bindings: Bound key bindings
_win_id: The window ID this keyparser is associated with.
_sequence: The currently entered key sequence
_modename: The name of the input mode associated with this keyparser.
_supports_count: Whether count is supported
Signals:
keystring_updated: Emitted when the keystring is updated.
arg: New keystring.
request_leave: Emitted to request leaving a mode.
arg 0: Mode to leave.
arg 1: Reason for leaving.
arg 2: Ignore the request if we're not in that mode
"""
keystring_updated = pyqtSignal(str)
request_leave = pyqtSignal(usertypes.KeyMode, str, bool)
do_log = True
passthrough = False
def __init__(self, win_id, parent=None, supports_count=True):
super().__init__(parent)
self._win_id = win_id
self._modename = None
self._sequence = keyutils.KeySequence()
self._count = ''
self._supports_count = supports_count
self.bindings = {}
config.instance.changed.connect(self._on_config_changed)
def __repr__(self):
return utils.get_repr(self, supports_count=self._supports_count)
def _debug_log(self, message):
"""Log a message to the debug log if logging is active.
Args:
message: The message to log.
"""
if self.do_log:
log.keyboard.debug(message)
def _handle_key(self, e):
"""Handle a new keypress.
Separate the keypress into count/command, then check if it matches
any possible command, and either run the command, ignore it, or
display an error.
Args:
e: the KeyPressEvent from Qt.
Return:
A QKeySequence match or None.
"""
key = e.key()
txt = keyutils.keyevent_to_string(e)
self._debug_log("Got key: 0x{:x} / text: '{}'".format(key, txt))
if not txt:
self._debug_log("Ignoring, no text char")
return QKeySequence.NoMatch
# if len(txt) == 1:
# category = unicodedata.category(txt)
# is_control_char = (category == 'Cc')
# else:
# is_control_char = False
# if (not txt) or is_control_char:
# self._debug_log("Ignoring, no text char")
# return QKeySequence.NoMatch
if (txt.isdigit() and self._supports_count and not
(not self._count and txt == '0')):
assert len(txt) == 1, txt
self._count += txt
return None
sequence = self._sequence.append_event(e)
match, binding = self._match_key(sequence)
if match == QKeySequence.NoMatch:
mappings = config.val.bindings.key_mappings
mapped = mappings.get(sequence, None)
if mapped is not None:
match, binding = self._match_key(mapped)
self._sequence = self._sequence.append_event(e)
if match == QKeySequence.ExactMatch:
self._debug_log("Definitive match for '{}'.".format(
self._sequence))
count = int(self._count) if self._count else None
self.clear_keystring()
self.execute(binding, count)
elif match == QKeySequence.PartialMatch:
self._debug_log("No match for '{}' (added {})".format(
self._sequence, txt))
elif match == QKeySequence.NoMatch:
self._debug_log("Giving up with '{}', no matches".format(
self._sequence))
self.clear_keystring()
else:
raise utils.Unreachable("Invalid match value {!r}".format(match))
return match
def _match_key(self, sequence):
"""Try to match a given keystring with any bound keychain.
Args:
sequence: The command string to find.
Return:
A tuple (matchtype, binding).
matchtype: Match.definitive, Match.partial or Match.none.
binding: - None with Match.partial/Match.none.
- The found binding with Match.definitive.
"""
assert sequence
assert not isinstance(sequence, str)
for seq, cmd in self.bindings.items():
assert not isinstance(seq, str), seq
match = sequence.matches(seq)
if match != QKeySequence.NoMatch:
return (match, cmd)
return (QKeySequence.NoMatch, None)
def handle(self, e):
"""Handle a new keypress and call the respective handlers.
Args:
e: the KeyPressEvent from Qt
Return:
True if the event was handled, False otherwise.
"""
match = self._handle_key(e)
# don't emit twice if the keystring was cleared in self.clear_keystring
if self._sequence:
self.keystring_updated.emit(self._count + str(self._sequence))
return match != QKeySequence.NoMatch
@config.change_filter('bindings')
def _on_config_changed(self):
self._read_config()
def _read_config(self, modename=None):
"""Read the configuration.
Config format: key = command, e.g.:
<Ctrl+Q> = quit
Args:
modename: Name of the mode to use.
"""
if modename is None:
if self._modename is None:
raise ValueError("read_config called with no mode given, but "
"None defined so far!")
modename = self._modename
else:
self._modename = modename
self.bindings = {}
for key, cmd in config.key_instance.get_bindings_for(modename).items():
assert not isinstance(key, str), key
assert cmd
self.bindings[key] = cmd
def execute(self, cmdstr, count=None):
"""Handle a completed keychain.
Args:
cmdstr: The command to execute as a string.
count: The count if given.
"""
raise NotImplementedError
def clear_keystring(self):
"""Clear the currently entered key sequence."""
if self._sequence:
self._debug_log("discarding keystring '{}'.".format(
self._sequence))
self._sequence = keyutils.KeySequence()
self._count = ''
self.keystring_updated.emit('')