Pico Proximity Sensor (LED Alert + POST request to API)

import machine
import network
import urequests as requests
import time
import bluetooth

# Define the onboard LED (you can choose any GPIO pin)
led_onboard = machine.Pin("LED", machine.Pin.OUT)

# Initialize WiFi
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
wlan.connect('your_wifi_ssid', 'your_wifi_password')

# Wait for connection or fail
max_wait = 10
while max_wait > 0:
    if wlan.status() < 0 or wlan.status() >= 3:
        break
    max_wait -= 1
    print('Waiting for WiFi connection...')
    time.sleep(1)

if wlan.status() != 3:
    raise RuntimeError('Network connection failed')
else:
    print('Connected to WiFi')
    status = wlan.ifconfig()
    print('IP address:', status[0])

# Initialize Bluetooth
ble = bluetooth.BLE()

# Callback when a central device (e.g., smartphone) connects
def on_connect(event, data):
    conn_handle, _, _ = data
    print("Connected to device:", conn_handle)
    led_onboard.on()  # Turn on the LED

# Callback when a central device disconnects
def on_disconnect(event, data):
    conn_handle, _, _ = data
    print("Disconnected from device:", conn_handle)
    led_onboard.off()  # Turn off the LED

# Set up BLE callbacks
ble.irq(handler=on_connect, event=bluetooth.IRQ_CENTRAL_CONNECT)
ble.irq(handler=on_disconnect, event=bluetooth.IRQ_CENTRAL_DISCONNECT)

# Start advertising (make the Pico discoverable)
ble.gap_advertise(interval_us=500000, adv_data=b"\x02\x01\x06\x03\x03\x09\x18")

# Callback function to send POST request
def send_post_request(timer):
    timestamp = machine.RTC().datetime()
    timestring = "%04d-%02d-%02d %02d:%02d:%02d" % (timestamp[0:3] + timestamp[4:7])
    api_endpoint = "https://your.api.endpoint.com/data"  # Replace with your API URL
    payload = {"timestamp": timestring, "event": "proximity_detected"}
    try:
        response = requests.post(api_endpoint, json=payload)
        print(timestring, "Status Code:", response.status_code)
        response.close()
    except Exception as e:
        print("Error sending POST request:", e)

# Initialize timer for periodic API requests
timer = machine.Timer()
timer.init(period=10000, mode=machine.Timer.PERIODIC, callback=send_post_request)