#!/usr/bin/env python3

# notify_low_mem --mem '14% 12%' --name 'stress' --pid '6666'

# output:
# Low memory: 14% 12%
# Fattest process: 6666, stress

from argparse import ArgumentParser
from subprocess import Popen, PIPE

parser = ArgumentParser()

parser.add_argument(
    '--mem',
    help="""available memory percent (15%, for example)""",
    default=None,
    type=str
)

parser.add_argument(
    '--pid',
    help="""pid""",
    default=None,
    type=str
)

parser.add_argument(
    '--name',
    help="""process name""",
    default=None,
    type=str
)

args = parser.parse_args()

pid = args.pid
name = args.name
mem = args.mem

title = 'Low memory: {}'.format(mem)

body = 'Fattest process: <b>{}</b>, <b>{}</b>'.format(pid, name)

# return list of tuples with
# username, DISPLAY and DBUS_SESSION_BUS_ADDRESS
def root_notify_env():

    ps_output_list = Popen(['ps', 'ae'], stdout=PIPE
        ).communicate()[0].decode().split('\n')

    lines_with_displays = []
    for line in ps_output_list:
        if ' DISPLAY=' in line and ' DBUS_SESSION_BUS_ADDRES' \
            'S=' in line and ' USER=' in line:
            lines_with_displays.append(line)

    # list of tuples with needments
    deus = []
    for i in lines_with_displays:
        for i in i.split(' '):
            if i.startswith('USER='):
                user = i.strip('\n').split('=')[1]
                continue
            if i.startswith('DISPLAY='):
                disp_value = i.strip('\n').split('=')[1][0:2]
                disp = 'DISPLAY=' + disp_value
                continue
            if i.startswith('DBUS_SESSION_BUS_ADDRESS='):
                dbus = i.strip('\n')
        deus.append(tuple([user, disp, dbus]))

    # unique list of tuples
    vult = []
    for user_env_tuple in set(deus):
        vult.append(user_env_tuple)

    return vult

b = root_notify_env()

if len(b) > 0:
    for i in b:
        username, display_env, dbus_env = i[0], i[1], i[2]
        Popen(['sudo', '-u', username, 'env', display_env,
                dbus_env, 'notify-send', '--icon=dialog-warning',
                '{}'.format(title), '{}'.format(body)])