#!/usr/bin/env python

# Adapted from:
#   - https://github.com/GStreamer/gst-python/blob/master/examples/helloworld.py
#   - With parts from https://cmusphinx.github.io/wiki/gstreamer/

import sys
import signal

import gi
gi.require_version('Gst', '1.0')
from gi.repository import GObject, Gst

#For IPC
import socket

def on_element_message(bus, message, loop):
    """Receive element messages from the bus."""
    msgtype = message.get_structure().get_name()
    if msgtype != 'pocketsphinx':
        return

    if message.get_structure().get_value('final'):
        final_result(message.get_structure().get_value('hypothesis'),
                     message.get_structure().get_value('confidence'))

def final_result(hyp, confidence):
    #Debug - reference https://docs.python.org/3/tutorial/inputoutput.html#fancier-output-formatting
    #print('Final: {}; confidence: {}'.format(hyp, confidence))
    send_command(hyp)

def send_command(command):
    # Create a TCP/IP socket
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

    # Connect the socket to the port where the server is listening
    server_address = ('localhost', 9999)
    #print >>sys.stderr, 'connecting to %s port %s' % server_address
    sock.connect(server_address)

    try:
        
        # Send data
        #print >>sys.stderr, 'sending "%s"' % command
        sock.sendall(command.encode()) #.encode per https://stackoverflow.com/a/37376668/424245
        
        # Look for the response
        amount_received = 0
        amount_expected = len(command)
        
        while amount_received < amount_expected:
            data = sock.recv(16)
            amount_received += len(data)
            #print >>sys.stderr, 'received "%s"' % data

    finally:
        #print >>sys.stderr, 'closing socket'
        sock.close()

def main(args):
    # Before using Python threads, or libraries using threads (GStreamer for example), you have to call GObject.threads_init(). Contrary to the naming, this function isn't provided by gobject but initializes thread support in PyGObject (it was called gobject.threads_init() in pygtk). Think of it as gi.threads_init().
    # Since PyGObject 3.10.2, calling GObject.threads_init() this is no longer needed.
    # Per https://wiki.gnome.org/Projects/PyGObject/Threading
    GObject.threads_init()
    Gst.init(None) # Cleanup via gst-deinit is normally not needed in an application as the resources will automatically be freed when the program terminates https://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-Gst.html#gst-deinit

    # Doc: https://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstParse.html#gst-parse-launch
    pipeline = Gst.parse_launch('autoaudiosrc ! queue ! audioconvert !' +
                            ' audioresample ! pocketsphinx name=asr !' +
                            ' fakesink') # to debug, use "fdsink fd=1" for last arg to write to stdout
    if not pipeline:
        sys.stderr.write("Failed to create pipeline\n")
        sys.exit(1)
    
    pocketsphinx = pipeline.get_by_name('asr')
    #From https://raspberrypi.stackexchange.com/a/56818
    pocketsphinx.set_property('kws', 'path/to/command.list')

    # create and event loop and feed gstreamer bus mesages to it
    loop = GObject.MainLoop.new(None, False)
    
    bus = pipeline.get_bus()
    bus.add_signal_watch()
    bus.connect ('message::element', on_element_message, loop)
    
    # start play back and listed to events
    pipeline.set_state(Gst.State.PLAYING)
    try:
        loop.run()
    except:
        pass

    # cleanup
    print('Cleaning up...')
    pipeline.set_state(Gst.State.NULL)

    # Block until pipeline changes state (per http://gstreamer-devel.966125.n4.nabble.com/Gstreamer-critical-on-pipeline-set-state-Gst-State-NULL-tp4678899p4678912.html), but the docs say changes to null are never async and suggest an alternate check (https://lazka.github.io/pgi-docs/Gst-1.0/classes/Element.html#Gst.Element.set_state)
    pipeline.get_state(Gst.CLOCK_TIME_NONE)
    loop.quit()
    print('Done!')

    return 0

if __name__ == '__main__':
    sys.exit(main(sys.argv))