#!/usr/bin/env python3
"""Interactive UART console to the re-bba-rb board (FT2232H channel B).

The BBA default build runs an interactive shell on this port ("rebbarb> "):
    help                      list commands
    udp broadcast [msg]       send a UDP broadcast on the test socket
    udp unicast <ip> [msg]    send a UDP datagram to <ip>

The bring-up diagnostics (w5100_selftest / w5100_udptest / w5100_regdump) just
stream a status line on the same port, so this works for those too.

Usage:
    sudo ./scripts/uart-console.py                 # /dev/ttyUSB1 @ 115200
    sudo ./scripts/uart-console.py /dev/ttyUSB0 115200
    ./scripts/uart-console.py --send "udp broadcast hi"   # one-shot, no tty
    ./scripts/uart-console.py --read 5                    # just dump 5s of output

Channel A of the FT2232H is the MPSSE/iceprog port; the UART is channel B, which
is normally the SECOND ttyUSB (…USB1).  Needs read/write on the device node —
run under sudo, or add yourself to the port's group.

Quit the interactive console with Ctrl-] (or Ctrl-C).
"""
import sys, time, argparse

try:
    import serial
except ImportError:
    sys.exit("needs pyserial:  pip install pyserial")


def main():
    ap = argparse.ArgumentParser(add_help=True)
    ap.add_argument("port", nargs="?", default="/dev/ttyUSB1")
    ap.add_argument("baud", nargs="?", type=int, default=115200)
    ap.add_argument("--send", metavar="CMD",
                    help="send one command, print the reply, exit")
    ap.add_argument("--read", metavar="SECONDS", type=float,
                    help="just read for N seconds and exit (no tty needed)")
    args = ap.parse_args()

    try:
        ser = serial.Serial(args.port, args.baud, timeout=0.1)
    except serial.SerialException as e:
        sys.exit(f"cannot open {args.port}: {e}\n(try: sudo {' '.join(sys.argv)})")

    # ── one-shot modes (safe in scripts / no controlling terminal) ───────────
    if args.read is not None:
        end = time.time() + args.read
        while time.time() < end:
            data = ser.read(256)
            if data:
                sys.stdout.write(data.decode("ascii", "replace"))
                sys.stdout.flush()
        return

    if args.send is not None:
        time.sleep(0.2); ser.reset_input_buffer()
        ser.write(args.send.encode() + b"\r")
        end = time.time() + 2.0
        buf = b""
        while time.time() < end:
            buf += ser.read(256)
        sys.stdout.write(buf.decode("ascii", "replace"))
        return

    # ── interactive console ─────────────────────────────────────────────────
    import termios, tty, select
    print(f"[uart-console] {args.port} @ {args.baud} 8N1 — Ctrl-] to quit\r")
    fd = sys.stdin.fileno()
    try:
        old = termios.tcgetattr(fd)
    except termios.error:
        old = None
    try:
        if old is not None:
            tty.setraw(fd)
        while True:
            r, _, _ = select.select([sys.stdin, ser], [], [], 0.05)
            if ser in r:
                data = ser.read(4096)
                if data:
                    sys.stdout.write(data.decode("ascii", "replace"))
                    sys.stdout.flush()
            if sys.stdin in r:
                ch = sys.stdin.buffer.read(1)
                if not ch or ch == b"\x1d":        # Ctrl-]
                    break
                if ch == b"\n":                     # send CR, the shell wants it
                    ch = b"\r"
                ser.write(ch)
    except KeyboardInterrupt:
        pass
    finally:
        if old is not None:
            termios.tcsetattr(fd, termios.TCSADRAIN, old)
        ser.close()
        print("\r\n[uart-console] closed")


if __name__ == "__main__":
    main()