Basic script to list BLE devices in Python using Bleak

#!/usr/bin/env python3
"""
BLE Device Scanner

This script scans for and lists all available Bluetooth Low Energy (BLE) devices
in the vicinity. It displays device information including name, address, and RSSI.

Requirements:
    - bleak library: pip install bleak

Usage:
    python list_ble_devices.py
"""

import asyncio
import sys
from bleak import BleakScanner
from datetime import datetime


async def scan_ble_devices(scan_time=10):
    """
    Scan for BLE devices and return a list of discovered devices.
    
    Args:
        scan_time (int): Duration to scan in seconds (default: 10)
    
    Returns:
        list: List of BleakDevice objects
    """
    print(f"Scanning for BLE devices for {scan_time} seconds...")
    print("=" * 50)
    
    try:
        devices = await BleakScanner.discover(timeout=scan_time)
        return devices
    except Exception as e:
        print(f"Error during scanning: {e}")
        return []


def display_devices(devices):
    """
    Display the discovered BLE devices in a formatted table.
    
    Args:
        devices (list): List of BleakDevice objects
    """
    if not devices:
        print("No BLE devices found.")
        return
    
    print(f"Found {len(devices)} BLE device(s):")
    print("-" * 80)
    print(f"{'Name':<25} {'Address':<20} {'RSSI':<6} {'Services'}")
    print("-" * 80)
    
    for device in devices:
        name = device.name if device.name else "<Unknown>"
        address = device.address
        rssi = "N/A"
        if hasattr(device, 'metadata') and 'rssi' in device.metadata:
            rssi_val = device.metadata['rssi']
            rssi = f"{rssi_val} dBm" if rssi_val is not None else "N/A"
        
        # Get service UUIDs if available
        services = ""
        if hasattr(device, 'metadata') and 'uuids' in device.metadata:
            services = ', '.join(device.metadata['uuids'][:2])  # Show first 2 UUIDs
            if len(device.metadata['uuids']) > 2:
                services += "..."
        
        print(f"{name:<25} {address:<20} {rssi:<6} {services}")


async def main():
    """
    Main function to run the BLE device scanner.
    """
    print("BLE Device Scanner")
    print(f"Scan started at: {datetime.now().strftime('%Y-%m-%d %H:%M:%S')}")
    print()
    
    # Check if scan time is provided as command line argument
    scan_time = 10
    if len(sys.argv) > 1:
        try:
            scan_time = int(sys.argv[1])
            if scan_time <= 0:
                raise ValueError("Scan time must be positive")
        except ValueError as e:
            print(f"Invalid scan time: {e}")
            print("Using default scan time of 10 seconds")
            scan_time = 10
    
    # Perform the scan
    devices = await scan_ble_devices(scan_time)
    
    # Display results
    print()
    display_devices(devices)
    
    # Additional device details
    if devices:
        print()
        print("Additional device information:")
        print("-" * 50)
        for i, device in enumerate(devices, 1):
            print(f"{i}. {device.name or '<Unknown>'} ({device.address})")
            metadata = getattr(device, 'metadata', None)
            if metadata:
                for key, value in metadata.items():
                    if key != 'uuids':  # uuids already shown above
                        print(f"   {key}: {value}")
            print()


if __name__ == "__main__":
    try:
        asyncio.run(main())
    except KeyboardInterrupt:
        print("\nScan interrupted by user.")
    except Exception as e:
        print(f"An error occurred: {e}")
        sys.exit(1)