######################## BEGIN LICENSE BLOCK ########################
# The Original Code is mozilla.org code.
#
# The Initial Developer of the Original Code is
# Netscape Communications Corporation.
# Portions created by the Initial Developer are Copyright (C) 1998
# the Initial Developer. All Rights Reserved.
#
# Contributor(s):
# Mark Pilgrim - port to Python
#
# This library 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 2.1 of the License, or (at your option) any later version.
#
# This library 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 this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
# 02110-1301 USA
######################### END LICENSE BLOCK #########################
import sys
from .mbcharsetprober import MultiByteCharSetProber
from .codingstatemachine import CodingStateMachine
from .chardistribution import SJISDistributionAnalysis
from .jpcntx import SJISContextAnalysis
from .mbcssm import SJISSMModel
from . import constants
class SJISProber(MultiByteCharSetProber):
def __init__(self):
MultiByteCharSetProber.__init__(self)
self._mCodingSM = CodingStateMachine(SJISSMModel)
self._mDistributionAnalyzer = SJISDistributionAnalysis()
self._mContextAnalyzer = SJISContextAnalysis()
self.reset()
def reset(self):
MultiByteCharSetProber.reset(self)
self._mContextAnalyzer.reset()
def get_charset_name(self):
return "SHIFT_JIS"
def feed(self, aBuf):
aLen = len(aBuf)
for i in range(0, aLen):
codingState = self._mCodingSM.next_state(aBuf[i])
if codingState == constants.eError:
if constants._debug:
sys.stderr.write(self.get_charset_name()
+ ' prober hit error at byte ' + str(i)
+ '\n')
self._mState = constants.eNotMe
break
elif codingState == constants.eItsMe:
self._mState = constants.eFoundIt
break
elif codingState == constants.eStart:
charLen = self._mCodingSM.get_current_charlen()
if i == 0:
self._mLastChar[1] = aBuf[0]
self._mContextAnalyzer.feed(self._mLastChar[2 - charLen:],
charLen)
self._mDistributionAnalyzer.feed(self._mLastChar, charLen)
else:
self._mContextAnalyzer.feed(aBuf[i + 1 - charLen:i + 3
- charLen], charLen)
self._mDistributionAnalyzer.feed(aBuf[i - 1:i + 1],
charLen)
self._mLastChar[0] = aBuf[aLen - 1]
if self.get_state() == constants.eDetecting:
if (self._mContextAnalyzer.got_enough_data() and
(self.get_confidence() > constants.SHORTCUT_THRESHOLD)):
self._mState = constants.eFoundIt
return self.get_state()
def get_confidence(self):
contxtCf = self._mContextAnalyzer.get_confidence()
distribCf = self._mDistributionAnalyzer.get_confidence()
return max(contxtCf, distribCf)