"""
modules/clap.py — clap / loud-sound trigger detector
Listens for a double-clap pattern to toggle FRIDAY on/off.
"""
import threading
import time

try:
    import numpy as np
    import sounddevice as sd
    AUDIO_OK = True
except ImportError:
    AUDIO_OK = False

CLAP_THRESHOLD  = 0.55   # RMS amplitude level
CLAP_WINDOW     = 0.8    # seconds between two claps to count as double-clap
COOLDOWN        = 2.0    # seconds to ignore after trigger


def watch_clap(callback, running_flag: list):
    """
    Run in a daemon thread. Calls callback() on double-clap detection.
    running_flag is a mutable [True] list; set [False] to stop.
    """
    if not AUDIO_OK:
        return

    last_clap  = 0.0
    last_trigger = 0.0

    def _audio_cb(indata, frames, time_info, status):
        nonlocal last_clap, last_trigger
        now = time.time()

        # cooldown guard
        if now - last_trigger < COOLDOWN:
            return

        rms = float(np.sqrt(np.mean(indata ** 2)))

        if rms > CLAP_THRESHOLD:
            if now - last_clap < CLAP_WINDOW:
                # double clap!
                last_trigger = now
                threading.Thread(target=callback, daemon=True).start()
                last_clap = 0.0   # reset
            else:
                last_clap = now

    try:
        with sd.InputStream(channels=1, samplerate=22050,
                            blocksize=1024, callback=_audio_cb):
            while running_flag[0]:
                time.sleep(0.1)
    except Exception:
        pass