controllerClient.py

# this is the 3ds client for the server
# it uses sokets and makes requests like this:
#
# ip:port/<input>
# ^   ^      ^
# |   |      |
# |   |      |- the pressed buttons (number)
# |   |-------- the servers port
# |------------ the servers ip
#
# the buttons are gotten from the _ctru(libctru in c) library
#
# all the config variables are in clientConfig.json

import json
import os
import socket
import struct
import time

import _ctru


def sleep(seconds):  # the defualt sleep function from the time module doesnt work, so we need to use this
    start = time.monotonic()
    while(time.monotonic() < start + seconds):
        pass
    return


script_dir = os.path.dirname(__file__)  # get script directory

rel_path = 'clientConfig.json'
# open the config file for the client
abs_file_path = os.path.join(script_dir, rel_path)
with open(abs_file_path) as f:
    config = json.loads(f.read())


def connect():
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)  # create a socket

    port = config['port']  # get the port of the server
    host = config['host']  # get the ip adress of the server

    print(f'connecting to {host} at {port}...')
    try:
        sock.connect((host, port,))  # connect to the server
        sock.setblocking(False)  # set the socket to non blocking
    except:
        return False

    return sock


sock = connect()
if not sock:
    raise BaseException("can not connect...")


def reconnect():
    global sock  # get the socket variable
    delay = config['reconnect']  # get the amount of reconnects before stopping
    while delay:  # try to reconnect
        sock = connect()
        print('reconnecting...', flush=True)
        if sock:  # if a connection is made, return
            print('connected!')
            return
        sleep(5)  # wait for 5 seconds untill reconnecting
        delay -= 1
    raise BaseException("can not reconnect...")


def send(packed):
    try:
        sock.sendall(packed)  # send request
    except:
        sock.close()
        reconnect()


def update(key_mask):
    packed = b'\x01' + struct.pack('!I', key_mask)  # pack the current key mask

    print(f'sending buttons ({key_mask})', flush=True)

    send(packed)


wait_frames = config['delay']  # frames to wait between checking inputs

old_mask = 0  # old key mask
frames = wait_frames  # frame counter for the time from the last input


while True:
    _ctru.hid_scan_input()
    key_mask = _ctru.hid_keys_held()  # get held keys
    if old_mask != key_mask and frames > wait_frames:
        update(key_mask)  # tell the server about the change
        frames = 0  # set the old frame counter to 0
    old_mask = key_mask  # set the old keymask to the current one
    frames += 1  # increase the frame counter
    try:
        pinged = sock.recv(1)
        print('pinged', flush=True)
        send(b'\x00')  # send a ping to the server
    except:
        pass