# IfcOpenShell - IFC toolkit and geometry engine # Copyright (C) 2021 Thomas Krijnen # # This file is part of IfcOpenShell. # # IfcOpenShell is free software: you can redistribute it and/or modify # it under the terms of the GNU Lesser General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # IfcOpenShell 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 Lesser General Public License for more details. # # You should have received a copy of the GNU Lesser General Public License # along with IfcOpenShell. If not, see . """Reads and writes encoded GlobalIds""" from __future__ import absolute_import from __future__ import division from __future__ import print_function import uuid import string from functools import reduce chars = string.digits + string.ascii_uppercase + string.ascii_lowercase + "_$" def compress(g): bs = [int(g[i : i + 2], 16) for i in range(0, len(g), 2)] def b64(v, l=4): return "".join([chars[(v // (64 ** i)) % 64] for i in range(l)][::-1]) return "".join([b64(bs[0], 2)] + [b64((bs[i] << 16) + (bs[i + 1] << 8) + bs[i + 2]) for i in range(1, 16, 3)]) def expand(g): def b64(v): return reduce(lambda a, b: a * 64 + b, map(lambda c: chars.index(c), v)) bs = [b64(g[0:2])] for i in range(5): d = b64(g[2 + 4 * i : 6 + 4 * i]) bs += [(d >> (8 * (2 - j))) % 256 for j in range(3)] return "".join(["%02x" % b for b in bs]) def split(g): return "{%s-%s-%s-%s-%s}" % (g[:8], g[8:12], g[12:16], g[16:20], g[20:]) def new(): return compress(uuid.uuid4().hex)