#!/usr/bin/env python3
"""
Plays a ding/timer sound at regular intervals aligned to round period marks
(e.g. every 15 min), with an optional offset so the sound plays a few seconds
before each mark.

Default: period 15 min, offset 15 s, 1 ding, sound asterisk.
Notification at :14:45, :29:45, :44:45, :59:45. Windows + Linux (stdlib).

  python scripts/python/utils/interval_timer_ding.py
  python scripts/python/utils/interval_timer_ding.py -p 30 -o 10
  python scripts/python/utils/interval_timer_ding.py -s exclamation -n 2
  python scripts/python/utils/interval_timer_ding.py -s /path/to/notify.wav
"""

import argparse
import math
import subprocess
import sys
import time
from datetime import datetime


def _seconds_since_midnight(dt: datetime) -> int:
    return dt.hour * 3600 + dt.minute * 60 + dt.second


def _next_ring_seconds(period_sec: int, offset_sec: int, now_sec: int) -> int:
    next_boundary = math.ceil(now_sec / period_sec) * period_sec
    ring_sec = next_boundary - offset_sec
    if ring_sec <= now_sec:
        ring_sec += period_sec
    return ring_sec


def _wait_seconds(period_sec: int, offset_sec: int) -> int:
    now = datetime.now()
    now_sec = _seconds_since_midnight(now)
    ring_sec = _next_ring_seconds(period_sec, offset_sec, now_sec)
    wait = ring_sec - now_sec
    return max(1, wait) if wait > 0 else 1


# Gap between repeated dings (Windows MessageBeep is async so need ~0.5s+)
_DING_GAP_SEC = 1.7
_WIN_BEEP_MS = 350

# Sound choice: None = use default, "asterisk"|"exclamation"|... = Windows preset, or file path
_sound: str | None = None


def _play_ding_windows() -> None:
    import winsound
    sound = _sound or "asterisk"
    if sound in ("asterisk", "exclamation", "hand", "question", "beep"):
        try:
            if sound == "asterisk":
                winsound.MessageBeep(winsound.MB_ICONASTERISK)
            elif sound == "exclamation":
                winsound.MessageBeep(winsound.MB_ICONEXCLAMATION)
            elif sound == "hand":
                winsound.MessageBeep(winsound.MB_ICONHAND)
            elif sound == "question":
                winsound.MessageBeep(winsound.MB_ICONQUESTION)
            else:  # beep
                winsound.Beep(800, _WIN_BEEP_MS)
            return
        except Exception:
            pass
    # Custom file path (SND_FILENAME only = blocking until sound finishes)
    try:
        winsound.PlaySound(sound, winsound.SND_FILENAME)
        return
    except Exception:
        pass
    try:
        winsound.Beep(800, _WIN_BEEP_MS)
    except Exception:
        sys.stdout.write("\a")
        sys.stdout.flush()


def _play_ding_linux() -> None:
    sound = _sound
    if sound:
        for cmd in (["paplay", sound], ["aplay", sound]):
            try:
                subprocess.run(cmd, capture_output=True, timeout=3)
                return
            except (FileNotFoundError, subprocess.TimeoutExpired, OSError):
                continue
    candidates = [
        ["paplay", "/usr/share/sounds/freedesktop/stereo/bell.oga"],
        ["paplay", "/usr/share/sounds/freedesktop/stereo/message.oga"],
        ["aplay", "/usr/share/sounds/alsa/Front_Center.wav"],
        ["aplay", "/usr/share/sounds/speech-dispatcher/test.wav"],
    ]
    for cmd in candidates:
        try:
            subprocess.run(cmd, capture_output=True, timeout=2)
            return
        except (FileNotFoundError, subprocess.TimeoutExpired, OSError):
            continue
    sys.stdout.write("\a")
    sys.stdout.flush()


def main() -> None:
    parser = argparse.ArgumentParser(
        description="Play a ding every N minutes, offset seconds before each round mark."
    )
    parser.add_argument(
        "-p", "--period",
        type=int,
        default=15,
        metavar="MIN",
        help="Interval in minutes between notifications (default: 15)",
    )
    parser.add_argument(
        "-o", "--offset",
        type=int,
        default=15,
        metavar="SEC",
        help="Seconds before each round mark to play (default: 15)",
    )
    parser.add_argument(
        "-s", "--sound",
        type=str,
        default=None,
        metavar="PRESET|PATH",
        help="Notification sound: Windows presets asterisk|exclamation|hand|question|beep, or path to .wav file (default: asterisk)",
    )
    parser.add_argument(
        "-n", "--dings",
        type=int,
        default=1,
        metavar="N",
        help="Number of dings per notification (default: 1, max: 10)",
    )
    args = parser.parse_args()

    global _sound
    _sound = args.sound

    if args.period < 1:
        parser.error("period must be >= 1")
    if args.offset < 0:
        parser.error("offset must be >= 0")
    if not 1 <= args.dings <= 10:
        parser.error("dings must be 1..10")

    period_sec = args.period * 60
    now = datetime.now()
    now_sec = _seconds_since_midnight(now)
    next_ring = _next_ring_seconds(period_sec, args.offset, now_sec)
    h = next_ring // 3600
    m = (next_ring % 3600) // 60
    s = next_ring % 60
    print(
        f"Period: {args.period} min, offset: {args.offset} s. "
        f"Next ding at {h:02d}:{m:02d}:{s:02d} (then every {args.period} min). "
        "Press Ctrl+C to stop."
    )

    play = _play_ding_windows if sys.platform == "win32" else _play_ding_linux
    while True:
        wait_sec = _wait_seconds(period_sec, args.offset)
        time.sleep(wait_sec)
        for i in range(args.dings):
            play()
            if i < args.dings - 1:
                time.sleep(_DING_GAP_SEC)
        print(f"[{datetime.now().strftime('%H:%M:%S')}] ding")


if __name__ == "__main__":
    main()