#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# Copyright 2006 Zuza Software Foundation
#
# This file is part of translate.
#
# translate 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 2 of the License, or
# (at your option) any later version.
#
# translate 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 this program; if not, see <http://www.gnu.org/licenses/>.

"""Supports a hybrid Unicode string that knows which encoding is preferable,
and uses this when converting to a string."""


# Python 3 compatibility
try:
    unicode
except NameError:
    unicode = str


class autoencode(unicode):

    def __new__(newtype, string=u"", encoding=None, errors=None):
        if isinstance(string, unicode):
            if errors is None:
                newstring = unicode.__new__(newtype, string)
            else:
                newstring = unicode.__new__(newtype, string, errors=errors)
            if encoding is None and isinstance(string, autoencode):
                newstring.encoding = string.encoding
            else:
                newstring.encoding = encoding
        else:
            if errors is None and encoding is None:
                newstring = unicode.__new__(newtype, string)
            elif errors is None:
                try:
                    newstring = unicode.__new__(newtype, string, encoding)
                except LookupError as e:
                    raise ValueError(str(e))
            elif encoding is None:
                newstring = unicode.__new__(newtype, string, errors)
            else:
                newstring = unicode.__new__(newtype, string, encoding, errors)
            newstring.encoding = encoding
        return newstring

    def join(self, seq):
        return autoencode(super(autoencode, self).join(seq))

    def __str__(self):
        if self.encoding is None:
            return super(autoencode, self).__str__()
        else:
            return self.encode(self.encoding)
