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

"""
Ansible module for reconfiguring debian packages.
(c) 2013, Sebastien Bocahu <sebastien.bocahu@nuxit.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/>.
"""

DOCUMENTATION = '''
---
module: dpkg_reconfigure
short_description: Reconfigure a Debian package.
description:
     - Reconfigure a Debian package using dpkg-reconfigure.
version_added: "1.2"
notes:
    - A number of questions has to be answered (depending on the package).
      Use 'DEBIAN_FRONTED=editor dpkg-reconfigure $pkg' for finding them.
options:
  pkg:
    description:
      - Package to configure.
    required: true
    default: null
    aliases: []
  answers:
    description:
      - Debconf configuration answer(s)/question(s).
    required: true
    default: null
    aliases: []
author: Sebastien Bocahu
'''

EXAMPLES = '''
# Set default locale to fr_FR.UTF-8, and generate en_US.UTF-8 as well:
dpkg_reconfigure:
   pkg: locales
   answers:
       locales/default_environment_locale: fr_FR.UTF-8
       locales/locales_to_be_generated: en_US.UTF-8 UTF-8, fr_FR.UTF-8 UTF-8

# Reconfigure roundcube, using configuration answers stored in a file:
dpkg_reconfigure: pkg=roundcube answers='$FILE(/path/dpkg-reconfigure/roundcube)'"
'''

import sys
import os
import pwd
import os.path
import re
import tempfile

def get_selections(module, pkg):
    cmd = [module.get_bin_path('debconf-show', True)]
    cmd.append(' %s' % pkg)
    rc, out, err = module.run_command(' '.join(cmd))

    if rc == 0:
        selections = {}
        for answer in out.split('\n'):
            item = re.search('^[* ] ([^:]+): (.*)$', answer)
            if item:
                value = item.group(2).strip()
                if value == 'true':
                    value = 'yes'
                elif value == 'false':
                    value = 'no'
                selections[ item.group(1).strip() ] = value
        return selections
    else:
        module.fail_json(msg=err)


def dpkg_reconfigure(module, pkg, wanted_config):
    editor_script = [ '#!/bin/sh', 'sed -i "$1" -f - <<EOF' ]
    for question in wanted_config:
        e_question = re.sub(r'([\\/&])', r'\\\1', question)
        e_answer = re.sub(r'([\\/&])', r'\\\1', wanted_config[question])
        editor_script.append('s/^\\(%s\\)\\s*=.*/\\1="%s"/' % (e_question, e_answer))
    editor_script.append('EOF')

    outfd, outsock_path = tempfile.mkstemp()
    tmp = os.fdopen(outfd,'w')
    tmp.write('\n'.join(editor_script))
    tmp.close()
    os.chmod(outsock_path, stat.S_IEXEC)

    cmd = [ 'EDITOR=%s DEBIAN_FRONTEND=editor' % outsock_path ]
    cmd.append(module.get_bin_path('dpkg-reconfigure', True))
    cmd.append(pkg)
    rc, out, err = module.run_command(' '.join(cmd), use_unsafe_shell=True)
    os.unlink(outsock_path)

    if rc == 0:
        return True, err
    else:
        return False, err


def enforce_state(module, params):

    pkg   = params["pkg"]
    answers  = params["answers"]

    wanted_config = {}

    if type(answers) is dict:
        wanted_config = answers
    else:
        for answer in answers.split('\n'):
            item = re.findall(r"[^\s]+", answer)
            if len(item) > 1:
                 wanted_config[ item[0].strip() ] = ' '.join(item[1:])
            elif len(item) == 1:
                 wanted_config[ item[0].strip() ] = ''

    for key in wanted_config:
        value = wanted_config[key]
        if isinstance(value, bool):
            if value:
                wanted_config[key] = 'yes'
            else:
                wanted_config[key] = 'no'

    current_config = get_selections(module, params["pkg"])

    already_configured = 1
    for answer in wanted_config:
        if not answer in current_config or current_config[answer] != wanted_config[answer]:
            already_configured = 0

    if already_configured:
        module.exit_json(changed=False, msg="Already configured")
    else:
        rc, msg = dpkg_reconfigure(module, pkg, wanted_config)
        if not rc:
            module.fail_json(msg=msg)

    params['changed'] = True
    params['msg'] = msg
    return params


def main():

    module = AnsibleModule(
        argument_spec = dict(
           pkg   = dict(required=True),
           answers  = dict(required=True),
        )
    )

    results = enforce_state(module, module.params)
    module.exit_json(**results)

# this is magic, see lib/ansible/module_common.py
#<<INCLUDE_ANSIBLE_MODULE_COMMON>>
main()