#! /usr/bin/env python3
# /opt/bin/backlight
# updated for Plasma 5.3 and later

import sys
import dbus
import notify2

# set whatever you like
icon = "/usr/share/icons/oxygen/32x32/devices/video-display.png"

bus = dbus.SessionBus()
power = bus.get_object('org.kde.Solid.PowerManagement',
                       '/org/kde/Solid/PowerManagement/Actions/BrightnessControl')
iface = dbus.Interface(power,
                       'org.kde.Solid.PowerManagement.Actions.BrightnessControl')

def main():
    brightness = int(iface.brightness())
    new_value = brightness + int(sys.argv[1])*2
    if new_value > 200:
        new_value=200
    if new_value < 0:
        new_value=0
    if brightness == new_value:
        return
    iface.setBrightness(new_value)
    if not notify2.init('backlight'):
        sys.exit(0) # notify2 is out of reach
    ni = notify2.Notification("Backlight", str(new_value//2), icon)
    ni.timeout = 5000
    if not ni.show():
        sys.exit(1) # notify2 is not operational

if __name__ == '__main__':
    main()