"""Displays bluetooth status (Bluez). Left mouse click launches manager app,
right click toggles bluetooth. Needs dbus-send to toggle bluetooth state.

Parameters:
    * bluetooth.device : the device to read state from (default is hci0)
    * bluetooth.manager : application to launch on click (blueman-manager)
    * bluetooth.dbus_destination : dbus destination (defaults to org.blueman.Mechanism)
    * bluetooth.dbus_destination_path : dbus destination path (defaults to /)
    * bluetooth.right_click_popup : use popup menu when right-clicked (defaults to True)

"""


import os
import re
import bumblebee.input
import bumblebee.output
import bumblebee.engine
import bumblebee.util
import bumblebee.popup
import logging


class Module(bumblebee.engine.Module):
    """Bluetooth module."""

    def __init__(self, engine, config):
        """Initialize."""
        super(Module, self).__init__(engine, config,
                                     bumblebee.output.Widget(
                                         full_text=self.status))

        device = self.parameter('device', 'hci0')
        self.manager = self.parameter('manager', 'blueman-manager')
        self._path = '/sys/class/bluetooth/{}'.format(device)
        self._status = 'Off'

        engine.input.register_callback(self, button=bumblebee.input.LEFT_MOUSE,
                                       cmd=self.manager)

        # determine whether to use pop-up menu or simply toggle the device on/off
        right_click_popup = bumblebee.util.asbool(
            self.parameter('right_click_popup', True))

        if right_click_popup:
            engine.input.register_callback(self,
                                           button=bumblebee.input.RIGHT_MOUSE,
                                           cmd=self.popup)
        else:
            engine.input.register_callback(self,
                                           button=bumblebee.input.RIGHT_MOUSE,
                                           cmd=self._toggle)

    def status(self, widget):
        """Get status."""
        return self._status

    def update(self, widgets):
        """Update current state."""
        if not os.path.exists(self._path):
            self._status = '?'
            return

        # search for whichever rfkill directory available
        try:
            dirnames = next(os.walk(self._path))[1]
            for dirname in dirnames:
                m = re.match(r'rfkill[0-9]+', dirname)
                if m is not None:
                    with open(os.path.join(self._path,
                                           dirname,
                                           'state'), 'r') as f:
                        state = int(f.read())
                        if state == 1:
                            self._status = 'On'
                        else:
                            self._status = 'Off'
                    return

        except IOError:
            self._status = '?'

    def manager(self, widget):
        """Launch manager."""
        bumblebee.util.execute(self.manager)

    def popup(self, widget):
        """Show a popup menu."""
        menu = bumblebee.popup.PopupMenu()
        if self._status == 'On':
            menu.add_menuitem('Disable Bluetooth')
        elif self._status == 'Off':
            menu.add_menuitem('Enable Bluetooth')
        else:
            return

        # show menu and get return code
        ret = menu.show(widget)
        if ret == 0:
            # first (and only) item selected.
            self._toggle()

    def _toggle(self, widget=None):
        """Toggle bluetooth state."""
        if self._status == 'On':
            state = 'false'
        else:
            state = 'true'

        dst = self.parameter('dbus_destination', 'org.blueman.Mechanism')
        dst_path = self.parameter('dbus_destination_path', '/')

        cmd = 'dbus-send --system --print-reply --dest={}'\
              ' {} org.blueman.Mechanism.SetRfkillState'\
              ' boolean:{}'.format(dst, dst_path, state)

        logging.debug('bt: toggling bluetooth')
        bumblebee.util.execute(cmd)

    def state(self, widget):
        """Get current state."""
        state = []

        if self._status == '?':
            state = ['unknown']
        elif self._status == 'On':
            state = ['ON']
        else:
            state = ['OFF']

        return state