# -*- coding: utf-8 -*-
#
# A simple demonstration of connecting to the UPDD and listening for digitiser
# events in Python. This uses asyncio in order to process UPDD events in
# Python's main thread rather than the UPDD's callback thread

import upddapi
import asyncio
import signal

digitiserCallback = None

async def configEventCallback(event_type, event):
    if event.pe.config.configEventType == upddapi.CONFIG_EVENT_CONNECT:
        print("Connected to UPDD")
        
        global digitiserCallback
        digitiserCallback = upddapi.create_event_callback_async(digitiserEventCallback)
        
        upddapi.TBApiRegisterEvent(0, 0, upddapi._EventTypeDigitiserEvent, digitiserCallback)
        
    if event.pe.config.configEventType == upddapi.CONFIG_EVENT_DISCONNECT:
        print("Disconnected from UPDD")


async def digitiserEventCallback(event_type, event):
    print(f"Received digitiser event from device {event.hDevice}")
    
    if event.pe.digitiserEvent.digitizerType == upddapi.DIGITIZER_TYPE_PEN:
        print(f"    pen {event.hStylus} {'down' if event.pe.digitiserEvent.de.touchEvent.touchingLeft else 'up'}")
    else:
        print(f"    touch {event.hStylus} {'down' if event.pe.digitiserEvent.de.touchEvent.touchingLeft else 'up'}")
    
    print(f"    screen coordinates: {event.pe.digitiserEvent.screenx} , {event.pe.digitiserEvent.screeny}")


def startup():
    upddapi.TBApiRegisterEvent(0, 0, upddapi._EventConfiguration,
                               upddapi.create_event_callback_async(configEventCallback))
    upddapi.TBApiOpen()


def shutdown():
    if digitiserCallback is not None:
        upddapi.TBApiUnregisterEvent(digitiserCallback)
    
    upddapi.TBApiUnregisterEvent(upddapi.create_event_callback_async(configEventCallback))

    upddapi.TBApiClose()


async def main():
    global loop
    stop_event = asyncio.Future()

    def handle_sigint():
        if not stop_event.done():
            print("\nReceived Ctrl+C, shutting down gracefully...")
            stop_event.set_result(None)

    startup()

    asyncio.get_running_loop().add_signal_handler(signal.SIGINT, handle_sigint)
    await stop_event
    
    shutdown()
    
    print("Done.")

if __name__ == "__main__":
    asyncio.run(main())