libervia-backend/sat/tools/common/utils.py

75 lines
2.3 KiB
Python

#!/usr/bin/env python3
# SàT: a XMPP client
# Copyright (C) 2009-2020 Jérôme Poisson (goffi@goffi.org)
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero 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 Affero General Public License for more details.
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
"""Misc utils for both backend and frontends"""
import collections.abc
def per_luminance(red, green, blue):
"""Caculate the perceived luminance of a RGB color
@param red(int): 0-1 normalized value of red
@param green(int): 0-1 normalized value of green
@param blue(int): 0-1 normalized value of blue
@return (float): 0-1 value of luminance (<0.5 is dark, else it's light)
"""
# cf. https://stackoverflow.com/a/1855903, thanks Gacek
return 0.299 * red + 0.587 * green + 0.114 * blue
def recursive_update(ori: dict, update: dict):
"""Recursively update a dictionary"""
# cf. https://stackoverflow.com/a/3233356, thanks Alex Martelli
for k, v in update.items():
if isinstance(v, collections.abc.Mapping):
ori[k] = recursive_update(ori.get(k, {}), v)
else:
ori[k] = v
return ori
class OrderedSet(collections.abc.MutableSet):
"""A mutable sequence which doesn't keep duplicates"""
# TODO: complete missing set methods
def __init__(self, values=None):
self._dict = {}
if values is not None:
self.update(values)
def __len__(self):
return len(self._dict)
def __iter__(self):
return iter(self._dict.keys())
def __contains__(self, item):
return item in self._dict
def add(self, item):
self._dict[item] = None
def discard(self, item):
try:
del self._dict[item]
except KeyError:
pass
def update(self, items):
self._dict.update({i: None for i in items})