from mercurial.i18n import _

from mercurial import cmdutil, commands, util

import os.path, re, sys

hgkeywords = 'Id|Header|Author|Date|Revision|RCSFile|Source'

def pretxnkw(ui, repo, hooktype, **args):

    '''Collects candidates for keyword expansion on commit

    and expands keywords in working dir.

    NOTE: for use in combination with hgext.keyword!'''

    if hooktype != 'pretxncommit':

        # bail out with error

        return True

    # reparse args, opts again as pretxncommit hook is silent about them

    sysargs, globalopts, cmdopts = commands.parse(ui, sys.argv[1:])[2:]

    files, match, anypats = cmdutil.matchpats(repo, sysargs, cmdopts)

    # validity checks should have been done already

    modified, added = repo.status(files=files, match=match)[:2]

    candidates = modified + added

    if not candidates:

        return False

    # only check files that have hgkwencode assigned as encode filter

    files = []

    # python2.4: files = set()

    for pat, opt in repo.ui.configitems('keyword'):

        if opt == 'expand':

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

            for candidate in candidates:

                if mf(candidate) and candidate not in files:

                    files.append(candidate)

                # python2.4:

                # if mf(candidate): files.add(candidate)

    if not files: # nothing to do

        return False

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

    strdate = util.datestr(date=date)

    shortuser = util.shortuser(user)

    shortdate = util.datestr(date=date, format=util.defaultdateformats[0])

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

    re_kw = re.compile(r'\$(%s)(: [^$]+? )?\$' % hgkeywords)

    for f in files:

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

        if not util.binary(data):

            def kwexpand(matchobj):

                RCSFile = os.path.basename(f)+',v'

                Source = os.path.join(repo.root, f)+',v'

                Revision = args['node'][:12]

                Date = strdate

                Author = user

                revdateauth = '%s %s %s' % (Revision, shortdate, shortuser)

                Header = '%s %s' % (Source, revdateauth)

                Id = '%s %s' % (RCSFile, revdateauth)

                return '$%s: %s $' % (

                        matchobj.group(1), eval(matchobj.group(1)))

            data, kwct = re_kw.subn(kwexpand, data)

            if kwct:

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

                # backup file?

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