# minimal sample showing how to write GTK3 indicator for Ubuntu Unity
# copyright 2012 Charl P. Botha <info@charlbotha.com>
# hereby released under the BSD license.

# use the PyGObject GObject introspection to use GTK+ 3
# also see
# http://readthedocs.org/docs/python-gtk-3-tutorial/en/latest/index.html
# http://developer.gnome.org/gtk3/stable/ (API reference)

from gi.repository import Gtk, GLib

try:
       from gi.repository import AppIndicator3 as AppIndicator
except:
       from gi.repository import AppIndicator

import re

class IndicatorCPUSpeed:
    def __init__(self):
        # param1: identifier of this indicator
        # param2: name of icon. this will be searched for in the standard them
        # dirs
        # finally, the category. We're monitoring CPUs, so HARDWARE.
        self.ind = AppIndicator.Indicator.new(
                            "indicator-cpuspeed",
                            "onboard-mono",
                            AppIndicator.IndicatorCategory.HARDWARE)

        # some more information about the AppIndicator:
        # http://developer.ubuntu.com/api/ubuntu-12.04/python/AppIndicator3-0.1.html
        # http://developer.ubuntu.com/resources/technologies/application-indicators/

        # need to set this for indicator to be shown
        self.ind.set_status (AppIndicator.IndicatorStatus.ACTIVE)

        # have to give indicator a menu
        self.menu = Gtk.Menu()

        # you can use this menu item for experimenting
        item = Gtk.MenuItem()
        item.set_label("Test")
        item.connect("activate", self.handler_menu_test)
        item.show()
        self.menu.append(item)

        # this is for exiting the app
        item = Gtk.MenuItem()
        item.set_label("Exit")
        item.connect("activate", self.handler_menu_exit)
        item.show()
        self.menu.append(item)

        self.menu.show()
        self.ind.set_menu(self.menu)

        # initialize cpu speed display
        self.update_cpu_speeds()
        # then start updating every 2 seconds
        # http://developer.gnome.org/pygobject/stable/glib-functions.html#function-glib--timeout-add-seconds
        GLib.timeout_add_seconds(2, self.handler_timeout)

    def get_cpu_speeds(self):
        """Use regular expression to parse speeds of all CPU cores from
        /proc/cpuinfo on Linux.
        """

        f = open('/proc/cpuinfo')
        # this gives us e.g. ['2300', '2300']
        s = re.findall('cpu MHz\s*:\s*(\d+)\.', f.read())
        # this will give us ['2.3', '2.3']
        f = ['%.1f' % (float(i) / 1000,) for i in s]
        return f

    def handler_menu_exit(self, evt):
        Gtk.main_quit()

    def handler_menu_test(self, evt):
        # we can change the icon at any time
        self.ind.set_icon("indicator-messages-new")

    def handler_timeout(self):
        """This will be called every few seconds by the GLib.timeout.
        """
        # read, parse and put cpu speeds in the label
        self.update_cpu_speeds()
        # return True so that we get called again
        # returning False will make the timeout stop
        return True

    def update_cpu_speeds(self):
        f = self.get_cpu_speeds()
        self.ind.set_label(' '.join(f), "8.8 8.8 8.8 8.8")

    def main(self):
        Gtk.main()

if __name__ == "__main__":
    ind = IndicatorCPUSpeed()
    ind.main()