#!/usr/bin/env python3
"""
Simple serial terminal for manual Helios laser testing.
Allows sending raw commands and viewing responses.
"""

import serial
import sys
from threading import Thread
import time

def read_from_port(ser):
    """Read data from serial port and display it."""
    while True:
        try:
            if ser.in_waiting:
                data = ser.read(ser.in_waiting)
                print(f"\n[RX] {data.decode('ascii', errors='replace')}", end='')
                sys.stdout.flush()
        except:
            break
        time.sleep(0.01)

def main():
    """Run interactive serial terminal."""
    port = "/dev/ttyUSB2"

    if len(sys.argv) > 1:
        port = sys.argv[1]

    try:
        ser = serial.Serial(
            port=port,
            baudrate=9600,
            bytesize=serial.EIGHTBITS,
            parity=serial.PARITY_NONE,
            stopbits=serial.STOPBITS_ONE,
            timeout=0.1
        )
        print(f"Connected to {port} at 9600 baud")
        print("Type commands and press Enter. Type 'quit' to exit.\n")

        # Start reader thread
        reader_thread = Thread(target=read_from_port, args=(ser,), daemon=True)
        reader_thread.start()

        while True:
            try:
                user_input = input("[TX] ")
                if user_input.lower() == 'quit':
                    break

                # Send command with carriage return
                command = user_input + '\r'
                ser.write(command.encode('ascii'))
                time.sleep(0.1)

            except KeyboardInterrupt:
                break
            except Exception as e:
                print(f"Error: {e}")

        ser.close()
        print("\nDisconnected")

    except Exception as e:
        print(f"Failed to open {port}: {e}")
        sys.exit(1)

if __name__ == "__main__":
    main()