mmgen-wallet/mmgen/tw/shared.py

#!/usr/bin/env python3
#
# MMGen Wallet, a terminal-based cryptocurrency wallet
# Copyright (C)2013-2025 The MMGen Project <mmgen@tuta.io>
# Licensed under the GNU General Public License, Version 3:
#   https://www.gnu.org/licenses
# Public project repositories:
#   https://github.com/mmgen/mmgen-wallet
#   https://gitlab.com/mmgen/mmgen-wallet

"""
tw.shared: classes and functions shared by all tracking wallet classes
"""

from ..objmethods import HiliteStr, InitErrors, MMGenObject
from ..obj import TwComment
from ..addr import MMGenID

class TwMMGenID(HiliteStr, InitErrors, MMGenObject):
	color = 'orange'
	width = 0
	trunc_ok = False
	def __new__(cls, proto, id_str):
		if isinstance(id_str, cls):
			return id_str
		try:
			ret = addr = disp = MMGenID(proto, id_str)
			sort_key, idtype = (ret.sort_key, 'mmgen')
		except Exception as e:
			try:
				coin, addr = id_str.split(':', 1)
				assert coin == proto.base_coin.lower(), (
					f'not a string beginning with the prefix {proto.base_coin.lower()!r}:')
				ret, sort_key, idtype, disp = (id_str, 'z_'+id_str, 'non-mmgen', 'non-MMGen')
				addr = proto.coin_addr(addr)
			except Exception as e2:
				return cls.init_fail(e, id_str, e2=e2)

		me = str.__new__(cls, ret)
		me.obj = ret
		me.disp = disp
		me.addr = addr
		me.sort_key = sort_key
		me.type = idtype
		me.proto = proto
		return me

	def fmt(self, width, /, **kwargs):
		return super().fmtc(self.disp, width, **kwargs)

# non-displaying container for TwMMGenID, TwComment
class TwLabel(str, InitErrors, MMGenObject):
	exc = 'BadTwLabel'
	passthru_excs = ('BadTwComment',)
	def __new__(cls, proto, text):
		if isinstance(text, cls):
			return text
		try:
			match text.split(None, 1):
				case [mmid_in]:
					comment = TwComment('')
				case [mmid_in, comment]:
					comment = TwComment(comment)
			mmid = TwMMGenID(proto, mmid_in)
			me = str.__new__(cls, mmid + (' ' + comment if comment else ''))
			me.mmid = mmid
			me.comment = comment
			me.proto = proto
			return me
		except Exception as e:
			return cls.init_fail(e, text)

def get_tw_label(proto, s):
	"""
	raise an exception on a malformed comment, return None on an empty or invalid label
	"""
	try:
		return TwLabel(proto, s)
	except Exception as e:
		if type(e).__name__ == 'BadTwComment': # do it this way to avoid importing .exception
			raise
		else:
			return None