#!/usr/bin/env python3
# networkd-notify: desktop notification integration for systemd-networkd
# Copyright(c) 2016-2017 by wave++ "Yuri D'Elia" <wavexx@thregr.org>
# Distributed under GPLv3+ (see COPYING) WITHOUT ANY WARRANTY.
from __future__ import print_function, division, generators, unicode_literals

import argparse
import subprocess
import sys
import os

import gi
from gi.repository import GLib as glib

import dbus
import dbus.mainloop.glib


# Constants
NETWORKCTL = ['/usr/bin/networkctl', '/bin/networkctl']
IWCONFIG = ['/usr/bin/iwconfig', '/sbin/iwconfig']
APP_NAME  = 'networkd'

STATE_IGN = {'carrier', 'degraded'}
STATE_MAP = {'off': 'offline',
             'no-carrier': 'disconnected',
             'dormant': 'configuring ...',
             'routable': 'online'}

# Nifty globals
IFACE_MAP = {}
NOTIFY_IF = None


def refresh_notify_if(bus):
    global NOTIFY_IF
    NOTIFY_IF = dbus.Interface(bus.get_object('org.freedesktop.Notifications',
                                              '/org/freedesktop/Notifications'),
                               'org.freedesktop.Notifications')


def notify(title, text, time=1000):
    if NOTIFY_IF:
        NOTIFY_IF.Notify(APP_NAME, 0, '', title, text, '', '', time)


def resolve_path(path_list):
    for path in path_list:
        if os.path.exists(path):
            return path
    return None


def update_iface_map():
    out = subprocess.check_output([NETWORKCTL, 'list', '--no-pager', '--no-legend'])
    IFACE_MAP.clear()
    for line in out.split(b'\n')[:-1]:
        fields = line.decode('ascii').split()
        IFACE_MAP[int(fields[0])] = fields[1]


def get_iface_data(iface):
    out = subprocess.check_output([NETWORKCTL, 'status', '--no-pager', '--no-legend', '--', iface])
    data = {}
    oldk = None
    for line in out.split(b'\n')[1:-1]:
        line = line.decode('ascii')
        k = line[:16].strip() or oldk
        oldk = k
        v = line[18:].strip()
        if k not in data:
            data[k] = v
        elif type(data[k]) == list:
            data[k].append(v)
        else:
            data[k] = [data[k], v]
    return data


def unquote(buf, char='\\'):
    idx = 0
    while True:
        idx = buf.find(char, idx)
        if idx < 0: break
        buf = buf[:idx] + buf[idx+1:]
        idx += 1
    return buf


def get_wlan_essid(iface):
    out = subprocess.check_output([IWCONFIG, '--', iface])
    line = out.split(b'\n')[0].decode('ascii')
    essid = line[line.find('ESSID:')+7:-3]
    return unquote(essid)


def property_changed(typ, data, _, path):
    if typ != 'org.freedesktop.network1.Link':
        return
    if not path.startswith('/org/freedesktop/network1/link/_'):
        return
    if 'OperationalState' not in data:
        return
    state = data['OperationalState']
    if state in STATE_IGN:
        return

    # http://thread.gmane.org/gmane.comp.sysutils.systemd.devel/36460
    idx = path[32:]
    idx = int(chr(int(idx[:2], 16)) + idx[2:])

    if idx not in IFACE_MAP:
        update_iface_map()
    iface = IFACE_MAP[idx]

    hstate = STATE_MAP.get(state, state)
    if state != 'routable':
        notify(iface, hstate)
    else:
        data = get_iface_data(iface)

        # append ESSID to the online state
        if data['Type'] == 'wlan':
            data['ESSID'] = get_wlan_essid(iface)
        if 'ESSID' in data and data['ESSID']:
            hstate += ' @ ' + data['ESSID']

        # filter out uninteresting addresses
        addrs = []
        if type(data['Address']) != list:
            addrs = [data['Address']]
        else:
            for addr in data['Address']:
                if addr.startswith('127.') or \
                   addr.startswith('fe80:'):
                    continue
                addrs.append(addr)

        notify(iface, '{}\n{}'.format(hstate, ', '.join(addrs)), 3000)


def name_owner_changed(name, old_owner, new_owner, path):
    if name == 'org.freedesktop.Notifications':
        refresh_notify_if(dbus.SessionBus())


if __name__ == '__main__':
    ap = argparse.ArgumentParser(description='networkd notification daemon')
    args = ap.parse_args()

    NETWORKCTL = resolve_path(NETWORKCTL)
    if NETWORKCTL is None:
        sys.exit("networkctl binary not found")

    IWCONFIG = resolve_path(IWCONFIG)
    if IWCONFIG is None:
        sys.exit("iwconfig binary not found")

    # interfaces never change at runtime, right??
    update_iface_map()

    # listen on system-wide bus for networkd events
    dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
    bus = dbus.SystemBus()
    bus.add_signal_receiver(property_changed,
                            bus_name='org.freedesktop.network1',
                            signal_name='PropertiesChanged',
                            path_keyword='path')

    # register on session bus for notification daemon changes
    sessionbus = dbus.SessionBus()
    sessionbus.add_signal_receiver(name_owner_changed,
                                   bus_name='org.freedesktop.DBus',
                                   signal_name='NameOwnerChanged',
                                   path_keyword='path')
    refresh_notify_if(sessionbus)

    # main loop
    mainloop = glib.MainLoop()
    mainloop.run()