#!/usr/bin/env python3
import sys
import RPi.GPIO as GPIO
import time
import subprocess

GPIO.setmode(GPIO.BCM)

# pins whose states will form the binary number
PINS = [17, 27, 9, 22]          # MSB → LSB

for p in PINS:
    try:
        GPIO.setup(p, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)
    except RuntimeError as e:
        sys.stderr.write(f"Pin {p} init error: {e}\n")
        GPIO.cleanup()
        sys.exit(1)

# read pins, build integer (bit 3 = pin 17, bit 2 = pin 27, bit 1 = pin 22, bit 0 = pin 10)
old_value=0
while(True):
    value = 0
    for i, p in enumerate(PINS):
        level = GPIO.input(p)
        value = (value << 1) | (1 if level else 0)
    
    if(value != old_value):
        #print(f"GPIO states [{', '.join(str(p) for p in PINS)}] -> 0b{value:04b} ({value})")
        print(str(value))
        command = "nc -N localhost 12345 < {}.dat".format(value)
        subprocess.run(command, shell=True, capture_output=False, text=True)

    old_value = value
    time.sleep(0.1)

    
GPIO.cleanup()