#!/usr/bin/python3
##
## This file is part of the sigrok-meter project.
##
## Copyright (C) 2013 Uwe Hermann <uwe@hermann-uwe.de>
##
## This program is free software; you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 2 of the License, or
## (at your option) any later version.
##
## This program is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with this program; if not, write to the Free Software
## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
##

from multiprocessing import Process, Queue
from gi.repository import Gtk, GObject
from sigrok.core import Context, Driver, Device, Session, Packet, Log
from sigrok.core import lowlevel as ll

def init_and_run(queue):
    def datafeed_in(device, packet):
        if packet.type == Packet.ANALOG:
            data = packet.payload.data
            unit, unit_str = packet.payload.unit, ""
            if unit == ll.SR_UNIT_VOLT:
                unit_str = " V"
            elif unit == ll.SR_UNIT_OHM:
                unit_str = " Ohm"
            elif unit == ll.SR_UNIT_AMPERE:
                unit_str = " A"
            mqflags, mqflags_str = packet.payload.unit, ""
            if mqflags & ll.SR_MQFLAG_AC:
                mqflags_str = " AC"
            elif mqflags & ll.SR_MQFLAG_DC:
                mqflags_str = " DC"
            for i in range(packet.payload.num_samples):
                queue.put("%f%s%s" % (data[i], unit_str, mqflags_str))

    # log = Log()
    # log.level = Log.SPEW
    context = Context()
    driver = context.drivers['voltcraft-vc820']
    device = driver.scan()[0]
    device.limit_samples = 1000
    session = Session(context)
    session.add_device(device)
    session.add_callback(datafeed_in)
    session.start()
    session.run()
    session.stop()

class SigrokMeter:
    def __init__(self):
        self.builder = Gtk.Builder()
        self.builder.add_from_file("sigrok-meter.glade")
        self.builder.connect_signals(self)
        self.value_label = self.builder.get_object("value_label")
        self.win = self.builder.get_object("mainwindow")
        self.win.show_all()
        self.queue = Queue()
        GObject.timeout_add(100, self.update_label_if_needed)

    def update_label_if_needed(self):
        try:
            t = self.queue.get_nowait()
            self.value_label.set_text(t)
        except:
            pass
        GObject.timeout_add(100, self.update_label_if_needed)

    def on_quit(self, *args):
        Gtk.main_quit(*args)

    def on_about(self, action):
        about = self.builder.get_object("aboutdialog")
        sr_pkg = ll.sr_package_version_string_get()
        sr_lib = ll.sr_lib_version_string_get()
        s = "Using libsigrok %s (lib version %s)." % (sr_pkg, sr_lib)
        about.set_comments(s)
        about.run()
        about.hide()

if __name__ == '__main__':
        s = SigrokMeter()
        process = Process(target=init_and_run, args=(s.queue,))
        process.start()
        Gtk.main()
        process.terminate()