# Copyright 2008 LShift Ltd

# Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>

#

# Authors:

# Paul Crowley <paul@lshift.net>

# Vadim Gelfer <vadim.gelfer@gmail.com>

#

# This software may be used and distributed according to the terms

# of the GNU General Public License, incorporated herein by reference.

from mercurial.i18n import _

from mercurial.node import *

from mercurial import util

import os

import ruleset

class Checker(object):

    '''acl checker.'''

    def __init__(self, ui, repo):

        self.ui = ui

        self.repo = repo

        self.rules = ruleset.rules_from_env()

        self.rules.set(user = os.environ['REMOTE_USER'])

        self.rules.set(repo = os.environ['HG_REPO_PATH'])

    def allow(self, node):

        '''return if access allowed, raise exception if not.'''

        ctx = self.repo.changectx(node)

        branch = ctx.branch()

        if not self.rules.allow("write", branch=branch, file=None):

            return False

        for f in ctx.files():

            if not self.rules.allow("write", branch=branch, file=f):

                return False

        self.ui.debug(_('%s: allowing changeset %s\n') % (__name__, short(node)))

        return True

    def check(self, node):

        if not self.allow(node):

            raise util.Abort(_('%s: access denied for changeset %s') %

                (__name__, short(node)))

def hook(ui, repo, hooktype, node=None, source=None, **kwargs):

    if hooktype != 'pretxnchangegroup':

        raise util.Abort(_('config error - hook type "%s" cannot stop '

                           'incoming changesets') % hooktype)

    c = Checker(ui, repo)

    start = repo.changelog.rev(bin(node))

    end = len(repo.changelog)

    for rev in xrange(start, end):

        c.check(repo.changelog.node(rev))