# Copyright (C) 2007-2009 Aaron Bentley and Panometrics, Inc.
#                         Ben Finney <benf@cybersource.com.au>
#                         Gianluca Montecchi <gian@grys.it>
#                         W. Trevor King <wking@drexel.edu>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

"""
Mercurial (hg) backend.
"""

import os
import os.path
import re
import shutil
import sys

import libbe
import base

if libbe.TESTING == True:
    import unittest
    import doctest


def new():
    return Hg()

class Hg(base.VCS):
    name='hg'
    client='hg'

    def __init__(self, *args, **kwargs):
        base.VCS.__init__(self, *args, **kwargs)
        self.versioned = True

    def _vcs_version(self):
        status,output,error = self._u_invoke_client('--version')
        return output

    def _vcs_get_user_id(self):
        status,output,error = self._u_invoke_client(
            'showconfig', 'ui.username')
        return output.rstrip('\n')

    def _vcs_detect(self, path):
        """Detect whether a directory is revision-controlled using Mercurial"""
        if self._u_search_parent_directories(path, '.hg') != None:
            return True
        return False

    def _vcs_root(self, path):
        status,output,error = self._u_invoke_client(
            'root', expect=(0,255), cwd=path)
        if status == 255:
            # "abort: There is no Mercurial repository here
            #  (.hg not found)!"
            return None
        return output.rstrip('\n')

    def _vcs_init(self, path):
        self._u_invoke_client('init', cwd=path)

    def _vcs_destroy(self):
        vcs_dir = os.path.join(self.repo, '.hg')
        if os.path.exists(vcs_dir):
            shutil.rmtree(vcs_dir)

    def _vcs_add(self, path):
        self._u_invoke_client('add', path)

    def _vcs_remove(self, path):
        self._u_invoke_client('rm', '--force', path)

    def _vcs_update(self, path):
        pass

    def _vcs_get_file_contents(self, path, revision=None):
        if revision == None:
            return base.VCS._vcs_get_file_contents(self, path, revision)
        else:
            status,output,error = \
                self._u_invoke_client('cat', '-r', revision, path)
            return output

    def _vcs_commit(self, commitfile, allow_empty=False):
        args = ['commit', '--logfile', commitfile]
        status,output,error = self._u_invoke_client(*args)
        if allow_empty == False:
            strings = ['nothing changed']
            if self._u_any_in_string(strings, output) == True:
                raise base.EmptyCommit()
        return self._vcs_revision_id(-1)

    def _vcs_revision_id(self, index, style='id'):
        args = ['identify', '--rev', str(int(index)), '--%s' % style]
        kwargs = {'expect': (0,255)}
        status,output,error = self._u_invoke_client(*args, **kwargs)
        if status == 0:
            id = output.strip()
            if id == '000000000000':
                return None # before initial commit.
            return id
        return None

    
if libbe.TESTING == True:
    base.make_vcs_testcase_subclasses(Hg, sys.modules[__name__])

    unitsuite =unittest.TestLoader().loadTestsFromModule(sys.modules[__name__])
    suite = unittest.TestSuite([unitsuite, doctest.DocTestSuite()])