from mercurial.i18n import _

from mercurial import commands, cmdutil, context, filelog, revlog, util

import os.path, re, sys

# supported keywords for use in regexes

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

def kwexpand(matchobj, repo, Revision, f, date, Author):

    '''Called by kwfilelog.read and pretxnkw.

    Sets supported keywords as local variables and evaluates them to

    their expansion if matchobj is equal to string representation.'''

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

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

    Date = util.datestr(date=date)

    revdateauth = '%s %s %s' % (Revision,       # %Y-%m-%d %H:%M:%S

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

            util.shortuser(Author))

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

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

    return '$%s: %s $' % (matchobj.group(1), eval(matchobj.group(1)))

                        def kwexpander(matchobj):

                            return kwexpand(matchobj,

                                    self._repo, c.changectx(), f,

                                    c.date(), c.user())

                        re_kw = re.compile(r'\$(%s)\$' % hgkeywords)

                        return re_kw.sub(kwexpander, data)

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

    '''pretxncommit hook that collects candidates for keyword expansion

    on commit and expands keywords in working dir.'''

    if hooktype != 'pretxncommit': # bail out with error

        return True

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

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

    # exclude tag and import

    if repr(cmd).split()[1] in ('tag', 'import_'):

        return False

    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 = [f for f in modified + added if not f.startswith('.hg')]

    if not candidates:

        return False

    # only check files that are configured in keyword section

    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:

        return False

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

    # expand both expanded and unexpanded keywords

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

    for f in files:

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

        if not util.binary(data):

            def kwexpander(matchobj):

                return kwexpand(matchobj,

                        repo, args['node'][:12], f, date, user)

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

            if kwct:

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

                # backup file?

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