input-remapper/keymapper/mapping.py

110 lines
3.2 KiB
Python

#!/usr/bin/python3
# -*- coding: utf-8 -*-
# key-mapper - GUI for device specific keyboard mappings
# Copyright (C) 2020 sezanzeb <proxima@hip70890b.de>
#
# This file is part of key-mapper.
#
# key-mapper 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.
#
# key-mapper 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 key-mapper. If not, see <https://www.gnu.org/licenses/>.
"""Contains and manages mappings."""
from keymapper.logger import logger
class Mapping:
"""Contains and manages mappings.
The keycode is always unique, multiple keycodes may map to the same
character.
"""
def __init__(self):
self._mapping = {}
self.changed = False
def __iter__(self):
"""Iterate over tuples of unique keycodes and their character."""
return iter(sorted(self._mapping.items()))
def __len__(self):
return len(self._mapping)
def change(self, previous_keycode, new_keycode, character):
"""Replace the mapping of a keycode with a different one.
Return True on success.
Parameters
----------
previous_keycode : int or None
If None, will not remove any previous mapping.
new_keycode : int
character : string
"""
try:
new_keycode = int(new_keycode)
except ValueError:
logger.error('Cannot use %s as keycode', new_keycode)
return False
if previous_keycode is not None:
try:
previous_keycode = int(previous_keycode)
except ValueError:
logger.error('Cannot use %s as keycode', previous_keycode)
return False
if new_keycode and character:
self._mapping[new_keycode] = str(character)
if new_keycode != previous_keycode:
# clear previous mapping of that code, because the line
# representing that one will now represent a different one.
self.clear(previous_keycode)
self.changed = True
return True
return False
def clear(self, keycode):
"""Remove a keycode from the mapping.
Parameters
----------
keycode : int
"""
if self._mapping.get(keycode) is not None:
del self._mapping[keycode]
self.changed = True
def empty(self):
"""Remove all mappings."""
self._mapping = {}
self.changed = True
def get(self, keycode):
"""Read the character that is mapped to this keycode.
Parameters
----------
keycode : int
"""
return self._mapping.get(keycode)
# one mapping object for the whole application that holds all
# customizations
custom_mapping = Mapping()