from mercurial import util, ui

from mercurial.i18n import gettext as _

import re

# regexp for single LF without CR preceding.

re_single_lf = re.compile('(^|[^\r])\n', re.MULTILINE)

def dumbdecode(s, cmd):

    # warn if already has CRLF in repository.

    # it might cause unexpected eol conversion.

    # see issue 302:

    #   http://www.selenic.com/mercurial/bts/issue302

    if '\r\n' in s:

        u = ui.ui()

        u.warn(_('WARNING: file in repository already has CRLF line ending \n'

                 ' which does not need eol conversion by win32text plugin.\n'

                 ' Please reconsider encode/decode setting in'

                 ' mercurial.ini or .hg/hgrc\n'

                 ' before next commit.\n'))

    # replace single LF to CRLF

    return re_single_lf.sub('\\1\r\n', s)

def dumbencode(s, cmd):

    return s.replace('\r\n', '\n')

def clevertest(s, cmd):

    if '\0' in s: return False

    return True

def cleverdecode(s, cmd):

    if clevertest(s, cmd):

        return dumbdecode(s, cmd)

    return s

def cleverencode(s, cmd):

    if clevertest(s, cmd):

        return dumbencode(s, cmd)

    return s

util.filtertable.update({

    'dumbdecode:': dumbdecode,

    'dumbencode:': dumbencode,

    'cleverdecode:': cleverdecode,

    'cleverencode:': cleverencode,

    })