#!/usr/bin/env python3
"""Capture Trikke sensor CSV output until interrupted with Ctrl-C."""

import argparse
import signal
import sys
from datetime import datetime
from pathlib import Path

import serial


def parse_args() -> argparse.Namespace:
    parser = argparse.ArgumentParser()
    parser.add_argument("--port", default="/dev/cu.usbmodem1134101")
    parser.add_argument("--baud", type=int, default=115200)
    parser.add_argument("--output", type=Path)
    return parser.parse_args()


def main() -> int:
    args = parse_args()
    output = args.output or Path("captures") / datetime.now().strftime(
        "motion_%Y%m%d_%H%M%S.csv"
    )
    output.parent.mkdir(parents=True, exist_ok=True)

    stop_requested = False

    def request_stop(_signum: int, _frame: object) -> None:
        nonlocal stop_requested
        stop_requested = True

    signal.signal(signal.SIGINT, request_stop)
    signal.signal(signal.SIGTERM, request_stop)

    sample_count = 0
    print(f"Recording {args.port} to {output}; press Ctrl-C to stop", flush=True)

    try:
        with serial.Serial(args.port, args.baud, timeout=0.25) as sensor, output.open(
            "w", encoding="utf-8", newline=""
        ) as capture:
            while not stop_requested:
                raw_line = sensor.readline()
                if not raw_line:
                    continue

                line = raw_line.decode("utf-8", errors="replace").rstrip("\r\n")
                capture.write(line + "\n")

                if line and line[0].isdigit() and line.count(",") == 13:
                    sample_count += 1
                    if sample_count % 500 == 0:
                        capture.flush()
                        print(f"  {sample_count} samples captured", flush=True)
    except serial.SerialException as exc:
        print(f"Serial error: {exc}", file=sys.stderr)
        return 1

    print(f"Stopped after {sample_count} samples; saved {output}", flush=True)
    return 0


if __name__ == "__main__":
    raise SystemExit(main())