#!/usr/bin/python
# -*- coding: utf-8 -*-

# (c) 2012, Michael DeHaan <michael.dehaan@gmail.com>
#
# This file is part of Ansible
#
# Ansible 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 3 of the License, or
# (at your option) any later version.
#
# Ansible 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 Ansible.  If not, see <http://www.gnu.org/licenses/>.

# I wanted to keep this simple at first, so for now this checks out
# from the given branch of a repo at a particular SHA or
# tag.  Latest is not supported, you should not be doing
# that. Contribs welcome! -- MPD

# requires subversion on the client.

import re

# TODO test scenarios:
# hacking/test-module -m library/subversion ; cat /tmp/subversion.log
# hacking/test-module -m library/subversion -a "repo=\"svn+ssh://pen.syskey.com/opt/subversion/gnconf\"" ; cat /tmp/subversion.log
# hacking/test-module -m library/subversion -a "dest=\"/tmp/gnconf\"" ; cat /tmp/subversion.log
# when /tmp/gnconf doesn't exist:
# hacking/test-module -m library/subversion -a "repo=\"svn+ssh://pen.syskey.com/opt/subversion/gnconf\" dest=\"/tmp/gnconf\"" ; cat /tmp/subversion.log
# when /tmp/gnconf is a folder, but its not an svn repo
# hacking/test-module -m library/subversion -a "repo=\"svn+ssh://pen.syskey.com/opt/subversion/gnconf\" dest=\"/tmp/gnconf\"" ; cat /tmp/subversion.log
# when /tmp/gnconf is a folder, but its a file (not a folder)
# hacking/test-module -m library/subversion -a "repo=\"svn+ssh://pen.syskey.com/opt/subversion/gnconf\" dest=\"/tmp/gnconf\"" ; cat /tmp/subversion.log
# when /tmp/gnconf is a folder, when its a different svn URL
# hacking/test-module -m library/subversion -a "repo=\"svn+ssh://pen.syskey.com/opt/subversion/gnconf\" dest=\"/tmp/gnconf\"" ; cat /tmp/subversion.log
# when /tmp/gnconf is a folder, when its a different revision
# hacking/test-module -m library/subversion -a "repo=\"svn+ssh://pen.syskey.com/opt/subversion/gnconf\" dest=\"/tmp/gnconf\"" ; cat /tmp/subversion.log

def get_version(dest):
    ''' samples the version of the git repo '''
    os.chdir(dest)
    cmd = "svn info | grep Revision"
    return os.popen(cmd).read()

def checkout(repo, dest):
    ''' makes a new svn repo if it does not already exist '''
    cmd = "svn co %s %s" % (repo, dest)
    cmd = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    (out, err) = cmd.communicate()
    rc = cmd.returncode
    return (rc, out, err)

def reset(dest):
    '''
    throw away any changes?
    TODO doesn't seem like a good idea to me...
    TODO throw away non-tracked files?
      -- svn st | grep '?' | awk '{print $2}' | xargs rm -rf
    '''
    os.chdir(dest)
    cmd = "svn revert -R ."
    cmd = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    (out, err) = cmd.communicate()
    rc = cmd.returncode
    return (rc, out, err)

def update(module, dest, version):
    ''' update an existing svn repo '''
    os.chdir(dest)
    cmd = ''
    if version != 'HEAD':
        cmd = "svn up -r %s" % version
    else:
        cmd = "svn up"
    cmd = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    (out, err) = cmd.communicate()
    rc = cmd.returncode
    return (rc, out, err)

# ===========================================

def main():
    module = AnsibleModule(
        argument_spec = dict(
            dest=dict(required=True),
            repo=dict(required=True, aliases=['name']),
            revision=dict(default='HEAD')
        )
    )

    dest    = module.params['dest']
    repo    = module.params['repo']
    revision = module.params['revision']

    rc, out, err, status = (0, None, None, None)

    # if there is no .svn folder, do a checkout
    # else update.
    before = None
    if not os.path.exists("%s/.svn" % (dest)):
        (rc, out, err) = checkout(repo, dest)
        if rc != 0:
            module.fail_json(msg=err)
    else:
        # else do an update
        before = get_version(dest)
        (rc, out, err) = reset(dest)
        if rc != 0:
            module.fail_json(msg=err)

    # handle errors from checkout or pull
    if err.find('ERROR') != -1:
        module.fail_json(msg=err)

    # switch to version specified regardless of whether
    # we cloned or pulled
    (rc, out, err) = update(module, dest, revision)
    if rc != 0:
        module.fail_json(msg=err)

    # determine if we changed anything
    after = get_version(dest)
    changed = False

    if before != after:
        changed = True

    module.exit_json(changed=changed, before=before, after=after, msg="")

# include magic from lib/ansible/module_common.py
#<<INCLUDE_ANSIBLE_MODULE_COMMON>>
main()