ThirdParty/CharDet/chardet/charsetgroupprober.py

######################## BEGIN LICENSE BLOCK ########################
# The Original Code is Mozilla Communicator client 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 constants, sys
from charsetprober import CharSetProber

class CharSetGroupProber(CharSetProber):
    def __init__(self):
        CharSetProber.__init__(self)
        self._mActiveNum = 0
        self._mProbers = []
        self._mBestGuessProber = None
        
    def reset(self):
        CharSetProber.reset(self)
        self._mActiveNum = 0
        for prober in self._mProbers:
            if prober:
                prober.reset()
                prober.active = constants.True
                self._mActiveNum += 1
        self._mBestGuessProber = None

    def get_charset_name(self):
        if not self._mBestGuessProber:
            self.get_confidence()
            if not self._mBestGuessProber: return None
#                self._mBestGuessProber = self._mProbers[0]
        return self._mBestGuessProber.get_charset_name()

    def feed(self, aBuf):
        for prober in self._mProbers:
            if not prober: continue
            if not prober.active: continue
            st = prober.feed(aBuf)
            if not st: continue
            if st == constants.eFoundIt:
                self._mBestGuessProber = prober
                return self.get_state()
            elif st == constants.eNotMe:
                prober.active = constants.False
                self._mActiveNum -= 1
                if self._mActiveNum <= 0:
                    self._mState = constants.eNotMe
                    return self.get_state()
        return self.get_state()

    def get_confidence(self):
        st = self.get_state()
        if st == constants.eFoundIt:
            return 0.99
        elif st == constants.eNotMe:
            return 0.01
        bestConf = 0.0
        self._mBestGuessProber = None
        for prober in self._mProbers:
            if not prober: continue
            if not prober.active:
                if constants._debug:
                    sys.stderr.write(prober.get_charset_name() + ' not active\n')
                continue
            cf = prober.get_confidence()
            if constants._debug:
                sys.stderr.write('%s confidence = %s\n' % (prober.get_charset_name(), cf))
            if bestConf < cf:
                bestConf = cf
                self._mBestGuessProber = prober
        if not self._mBestGuessProber: return 0.0
        return bestConf
#        else:
#            self._mBestGuessProber = self._mProbers[0]
#            return self._mBestGuessProber.get_confidence()