# $Hg$

from mercurial import demandimport

demandimport.enable()

from mercurial.i18n import _

import mercurial.util, re

# name of keyword encode filter:

kwencodefilter = 'hgkwencode'

# look for <Dollar>Hg<Dollar>

kwtrigger = '%sHg$' % '$'

def wwritekw(ui, repo, f, text):

    '''Writes text with kwupdates keywords to f in working directory.'''

    ui.note(_('expanding keywords in %s\n' % f))

#   # backup file (?)

#   absfile = repo.wjoin(f)

#   mercurial.util.copyfile(absfile, absfile+'.kwbak')

    repo.wfile(f, 'w').write(text)

def expandkw(ui, repo, node, cid, candidates, update=False):

    '''Important: returns False on success, True on failure.'''

    # only check files that have hgkwencode assigned as encode filter

    files = []

    for pat, cmd in repo.ui.configitems('encode'):

        if cmd.endswith(kwencodefilter):

            mf = mercurial.util.matcher(repo.root, '', [pat], [], [])[1]

            for candidate in candidates:

                if mf(candidate):

                    # check again that there really are no duplicates

                    # if candidate not in files ???

                    files.append(candidate)

    if not files: # nothing to do

        return False

    user, date = repo.changelog.read(node)[1:3]

    user = mercurial.util.shortuser(user)

    date = mercurial.util.datestr(date=date,

            format=mercurial.util.defaultdateformats[2])

                                  # %Y-%m-%d %H:%M

    # collect filenames that were changed by hg update

    kwupdates = []

    for f in files:

        text = repo.wfile(f).read()

        kwrepl = '%sHg: %s,v %s %s %s $' % ('$', f, cid, date, user)

        if update and text.find(kwtrigger) > -1:

            text = text.replace(kwtrigger, kwrepl)

            wwritekw(ui, repo, f, text)

            kwupdates.append(f)

        elif not update:

            re_kw = re.compile(r'[$]Hg(: %s,v [a-z0-9]{12} [^$]+? )?\$' % f)

            text, kwct = re_kw.subn(kwrepl, text)

            if kwct:

                wwritekw(ui, repo, f, text)

    if kwupdates:

        # cheat hg to believe that updated files were not modified

        repo.dirstate.update(kwupdates, 'n')

    return False