#!/usr/bin/python -tt
# (c) 2012, Flowroute LLC
# Written by Matthew Williams <matthew@flowroute.com>
# Based on yum module written by Seth Vidal <skvidal at fedoraproject.org>
#
# 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/>.
#


import os
import sys
import apt
import shlex
import subprocess


try:
    import json
except ImportError:
    import simplejson as json

def run_apt(command):
    try:
        cmd = subprocess.Popen(command, shell=True, 
            stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        out, err = cmd.communicate()
    except (OSError, IOError), e:
        rc = 1
        err = str(e)
        out = ''
    except:
        rc = 1
        err = traceback.format_exc()
        out = ''

        if out is None:
           out = ''
        if err is None:
           err = ''
    else:
        rc = cmd.returncode
        
    return rc, out, err

def ensure(state, pkgspec):
    cache = apt.Cache()
    cache.update()
    cache.open(None)
    try:
        pkg = cache[pkgspec]
    except:
        msg = "No package matching '%s' is available" % pkgsepc
        return {'changed': False, 'failed': True, 'msg': msg}
    if state == 'installed':
        #check if package is installed
        if pkg.is_installed:
            return {'changed': False, 'failed': False}
        cmd = "apt-get -q -y install '%s'" % pkgspec
        rc, out, err = run_apt(cmd)
        #pkg.mark_install()
        #cache.commit(apt.progress.base.OpProgress())

    elif state == 'removed':
        #check if package is installed
        if not pkg.is_installed:
            return {'changed': False, 'failed': False}
        cmd = "apt-get -q -y remove '%s'" % pkgspec
        rc, out, err = run_apt(cmd)
        #pkg.mark_delete()
        #cache.commit(apt.progress.base.OpProgress())
    else:
        return {'failed': True, 'msg': "Unknown state: %s" % state }
    
    return {'changed': True, 'failed': False}

def update(args):
    #generic update routine 
    pass

def remove_only(pkgspec):
    # remove this pkg and only this pkg - fail if it will require more to remove
    pass

def main():
    # state=installed pkg=pkgspec
    # state=removed pkg=pkgspec
    
    if len(sys.argv) == 1:
        msg = "the apt module requires arguments (-a)"
        return 1, msg

    argfile = sys.argv[1]
    if not os.path.exists(argfile):
        msg = "Argument file not found"
        return 1, msg

    args = open(argfile, 'r').read()
    items = shlex.split(args)

    if not len(items):
        msg = "the apt module requires arguments (-a)"
        return 1, msg

    # if nothing else changes - it fails
    results = { 'changed':False, 
                'failed':True, 
                'results':'', 
                'errors':'', 
                'msg':"; ".join(items) }
    params = {}
    for x in items:
        try:
            (k, v) = x.split("=", 1)
        except ValueError:
            msg = "invalid arguments: %s" % args
            return 1, msg
            
        params[k] = v

    if 'state' in params:
        if 'pkg' not in params:
            results['msg'] = "No pkg specified"
        else:
            state = params['state']
            pkgspec = params['pkg']

            devnull = open(os.devnull, 'w')
            results = ensure(state, pkgspec)
    print json.dumps(results)
    return 0, None

if __name__ == "__main__":
    rc, msg = main()
    if rc != 0: # something went wrong emit the msg
        print json.dumps({
            "failed" : bool(rc),
            "msg" : msg
        })   
        sys.exit(rc)