import bluetooth
from micropython import const


# i just made a UUID up and changed the last number to change what protocol you're using
SERVICE_UUID = bluetooth.UUID("E1898FF7-5063-4441-a6eb-526073B00001")
TX_UUID = bluetooth.UUID("E1898FF7-5063-4441-a6eb-526073B00002")
RX_UUID = bluetooth.UUID("E1898FF7-5063-4441-a6eb-526073B00003")

TX_CHAR = (TX_UUID, bluetooth.FLAG_NOTIFY)
RX_CHAR = (RX_UUID, bluetooth.FLAG_WRITE)

SERVICE = (SERVICE_UUID, (TX_CHAR, RX_CHAR))

IRQ_CONNECT = const(1)
IRQ_DISCONNECT = const(2)
IRQ_GATTS_WRITE = const(3)


class BluetoothHandler:
    def __init__(self):
        print("Initializing Bluetooth...")
        self.ble = bluetooth.BLE()
        self.ble.active(True)
        self.ble.irq(self.irq)
        
        
        self.mac_address = self._get_mac_address()
        print(f"Mac Address: {self.mac_address}")
        self.ble.config(gap_name="NODE-" + self.mac_address)
        
        ((self.tx_handle, self.rx_handle),) = self.ble.gatts_register_services((SERVICE,))
        
        self.connections = set()
        
        self.advertise()
        
    def _get_mac_address(self):
        mac = self.ble.config("mac")[1]
        return ':'.join('{:02X}'.format(b) for b in mac)
        
    def advertise(self):
        print("Advertising Bluetooth...")
        # note: \x02\x01\x06\x0C\x09 is the BLE header that tells other devices we're BLE only and discoverable
        self.ble.gap_advertise(100_000, b"\x02\x01\x06\x0C\x09NODE-" + self.mac_address.encode())
        
    def irq(self, event, data):
        print(f"BLUETOOTH IRQ | EVENT: {event}, DATA: {data}")
        if event == IRQ_CONNECT:
            conn_handle, _, _ = data
            self.connections.add(conn_handle)
        elif event == IRQ_DISCONNECT:
            conn_handle, _, _ = data
            self.connections.remove(conn_handle)
            self.advertise()
        elif event == IRQ_GATTS_WRITE:
            conn_handle, value_handle = data
            
            if value_handle == self.tx_handle:
                msg = self.ble.gatts_read(self.tx_handle)
                
                if msg == b"ping":
                    for conn in self.connections:
                        self.ble.gatts_notify(conn, self.rx_handle, b"pong")