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

# (c) 2012, Afterburn
# Written by Afterburn <http://github.com/afterburn> 
# Based on apt module written by Matthew Williams <matthew@flowroute.com>
#
# This module 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.
#
# This software 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 software.  If not, see <http://www.gnu.org/licenses/>.


DOCUMENTATION = '''
---
module: pacman
short_description: Package manager for Archlinux
description:
    - Manages Archlinux packages

version_added: "0.0.9"
options:
    pkg:
        description:
            - Define the state of a package (install/remove)
        required: true

author: Afterburn
notes:  []
examples:
    - code: "pacman: name=foo state=latest"
      description: update package db and install package foo
    - code: "pacman: name=foo state=absent"
      description: remove package foo
    - code: "pacman: name=foo,bar state=absent
      description: remove packages foo and bar (if installed)
      
'''


import json
import shlex
import os
import sys

PACMAN_PATH = "/usr/bin/pacman"

def query_package(module, name, state="installed"):

    # query_package returns True if the package does not
    # need to be installed/upgraded. Otherwise it returns 
    # False 


    # pacman -Q returns 0 if the package is installed,
    # 1 if it is not installed
    if state == "installed":
        rc = os.system("pacman -Q %s" % (name))

        if rc == 0:
            return True

        return False

    
    # pacman -Qu return 0 if update is needed
    # otherwise it returns 1
    rc = os.system("pacman -Qu %s" % (name))

    if rc == 1:
        return True

    return False

        
        


def update_package_db(module):
    rc = os.system("pacman -Syy")

    if rc != 0:
        module.fail_json(msg="could not update package db")

         

def remove_packages(module, packages):
    
    remove_c = 0
    # Using a for loop incase of error, we can report the package that failed
    for package in packages:
        # Query the package first, to see if we even need to remove
        if not query_package(module, package):
            continue

        rc = os.system("pacman -R %s --noconfirm" % (package))

        if rc != 0:
            module.fail_json(msg="failed to remove %s" % (package))
    
        remove_c += 1

    if remove_c > 0:

        module.exit_json(changed=True, msg="removed %s package(s)" % remove_c)

    module.exit_json(changed=False, msg="package(s) already absent")


def install_packages(module, packages):

    install_c = 0

    for package in packages:
        if query_package(module, package):
            continue

        rc = os.system("pacman -S %s --noconfirm" % (package))

        if rc != 0:
            module.fail_json(msg="failed to install %s" % (package))

        install_c += 1
    
    if install_c > 0:
        module.exit_json(changed=True, msg="installed %s package(s)" % (install_c))

    module.exit_json(changed=False, msg="package(s) already installed")


def main():
    module = AnsibleModule(
            argument_spec = dict(
                state = dict(default="installed", choices=["latest",
                                                           "installed",
                                                           "absent"]),
                name   = dict(default=None, aliases=["pkg"])))
                

    if not os.path.exists(PACMAN_PATH):
        module.fail_json(msg="cannot find pacman, looking for %s" % (PACMAN_PATH))

    p = module.params


    if p["name"] == None:
        module.fail_json(msg="no packages specified")

    pkgs = p["name"].split(",")

    if p["state"] == "installed":
        install_packages(module, pkgs)

    # To have the packages at "latest" we need
    # to update the package db first
    elif p["state"] == "latest":
        update_package_db(module)
        install_packages(module, pkgs)
     
    elif p["state"] == "absent":
        remove_packages(module, pkgs)

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