#!/home/noise/.local/share/uv/tools/powermon/bin/python
"""One-shot diagnostic: autodetect the currently-plugged FTDI, then
run 3 tests and print results.

  1. Passive listen 10 s @ 9600 baud.
  2. Passive listen 10 s @ 19200 baud.
  3. Active probe: send canonical 7E 01 01 00 FE 0D at 9600, wait 2 s.

Usage: port-probe <label>
"""
import glob, sys, time, serial

def autodetect():
    hits = sorted(glob.glob("/dev/serial/by-id/usb-FTDI_*"))
    return hits[0] if hits else None

def passive(port, baud, seconds):
    with serial.Serial(port, baud, bytesize=8, parity="N", stopbits=1, timeout=0.25) as p:
        p.reset_input_buffer()
        deadline = time.monotonic() + seconds
        buf = bytearray()
        while time.monotonic() < deadline:
            chunk = p.read(512)
            if chunk: buf.extend(chunk)
    return bytes(buf)

def probe(port, baud):
    frame = bytes([0x7E, 0x01, 0x01, 0x00, 0xFE, 0x0D])
    with serial.Serial(port, baud, bytesize=8, parity="N", stopbits=1, timeout=0.25) as p:
        p.reset_input_buffer()
        p.write(frame)
        deadline = time.monotonic() + 2.0
        buf = bytearray()
        while time.monotonic() < deadline:
            chunk = p.read(512)
            if chunk: buf.extend(chunk)
    return bytes(buf)

def modbus_q_count(buf):
    return sum(1 for i in range(len(buf) - 7)
               if buf[i+1] == 0x03 and buf[i+2] == 0 and buf[i+3] == 0 and buf[i+5] == 0x2f)

def main():
    label = sys.argv[1] if len(sys.argv) > 1 else "test"
    port = autodetect()
    if port is None:
        print("ERROR: no FTDI adapter visible at /dev/serial/by-id/usb-FTDI_*")
        sys.exit(2)
    print(f"=== {label} ===")
    print(f"adapter: {port}")
    for baud in (9600, 19200):
        buf = passive(port, baud, 10)
        print(f"\npassive @ {baud:>5}: {len(buf):4d} bytes ({len(buf)/10:4.1f} B/s)"
              f"  7E={buf.count(0x7E)}  0D={buf.count(0x0D)}"
              + (f"  mb_queries≈{modbus_q_count(buf)}" if baud == 19200 else ""))
        if buf:
            print(f"  first 80: {bytes(buf[:80]).hex(' ')}")
    buf = probe(port, 9600)
    print(f"\n7E probe @ 9600: reply {len(buf)} bytes")
    if buf:
        print(f"  hex: {bytes(buf).hex(' ')}")

if __name__ == "__main__":
    main()