1######################## BEGIN LICENSE BLOCK ########################
2# The Original Code is mozilla.org code.
3#
4# The Initial Developer of the Original Code is
5# Netscape Communications Corporation.
6# Portions created by the Initial Developer are Copyright (C) 1998
7# the Initial Developer. All Rights Reserved.
8#
9# Contributor(s):
10#   Mark Pilgrim - port to Python
11#
12# This library is free software; you can redistribute it and/or
13# modify it under the terms of the GNU Lesser General Public
14# License as published by the Free Software Foundation; either
15# version 2.1 of the License, or (at your option) any later version.
16#
17# This library is distributed in the hope that it will be useful,
18# but WITHOUT ANY WARRANTY; without even the implied warranty of
19# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
20# Lesser General Public License for more details.
21#
22# You should have received a copy of the GNU Lesser General Public
23# License along with this library; if not, write to the Free Software
24# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
25# 02110-1301  USA
26######################### END LICENSE BLOCK #########################
27
28from .constants import eStart
29from .compat import wrap_ord
30
31
32class CodingStateMachine:
33    def __init__(self, sm):
34        self._mModel = sm
35        self._mCurrentBytePos = 0
36        self._mCurrentCharLen = 0
37        self.reset()
38
39    def reset(self):
40        self._mCurrentState = eStart
41
42    def next_state(self, c):
43        # for each byte we get its class
44        # if it is first byte, we also get byte length
45        # PY3K: aBuf is a byte stream, so c is an int, not a byte
46        byteCls = self._mModel['classTable'][wrap_ord(c)]
47        if self._mCurrentState == eStart:
48            self._mCurrentBytePos = 0
49            self._mCurrentCharLen = self._mModel['charLenTable'][byteCls]
50        # from byte's class and stateTable, we get its next state
51        curr_state = (self._mCurrentState * self._mModel['classFactor']
52                      + byteCls)
53        self._mCurrentState = self._mModel['stateTable'][curr_state]
54        self._mCurrentBytePos += 1
55        return self._mCurrentState
56
57    def get_current_charlen(self):
58        return self._mCurrentCharLen
59
60    def get_coding_state_machine(self):
61        return self._mModel['name']
62