#!/usr/bin/env python3
"""
1/2 Lens VAR -- physical button listener.

Turns a press on a paired Bluetooth remote (or any USB button that types a key)
into a "save the last 30 seconds" replay. The button is JUST a button -- it sends
a keystroke; this script hears that keystroke and calls the app's replay endpoint.

  press button  ->  keystroke  ->  this script  ->  GET /api/replay  ->  30s clip

--------------------------------------------------------------------
STEP 1 - find out which key your remote sends (run once):
    python3 button_listener.py --learn
  ...then press the remote. It prints the key name. Copy it.

STEP 2 - run it for real with that key (example: the remote sends "enter"):
    python3 button_listener.py --key enter

  Leave it running. Every press now makes a clip.
--------------------------------------------------------------------

Install (one time):
    pip install pynput --break-system-packages
"""
import argparse, sys, time, json, urllib.request

def fire(url, timeout=8):
    try:
        with urllib.request.urlopen(url, timeout=timeout) as r:
            data = json.loads(r.read().decode() or "{}")
        watch = data.get("watchUrl") or data.get("url") or ""
        print(f"  ✔ clip saved  {watch}")
    except Exception as e:
        print(f"  ✘ could not reach the app ({e}). Is it running on this machine?")

def keyname(key):
    """A stable, lowercase name for a pressed key (works for letters and special keys)."""
    try:
        if hasattr(key, "char") and key.char is not None:
            return key.char.lower()
    except Exception:
        pass
    return str(key).replace("Key.", "").lower()

def main():
    ap = argparse.ArgumentParser()
    ap.add_argument("--url", default="http://localhost:4000/api/replay",
                    help="the app's replay endpoint (default: this machine, port 4000)")
    ap.add_argument("--key", default="enter",
                    help="the key your remote sends (see --learn). e.g. enter, space, media_volume_up")
    ap.add_argument("--debounce", type=float, default=2.0,
                    help="seconds to ignore repeat presses (stops double clips)")
    ap.add_argument("--learn", action="store_true",
                    help="just print the name of every key you press, then quit")
    args = ap.parse_args()

    try:
        from pynput import keyboard
    except ImportError:
        sys.exit("Missing package. Run:  pip install pynput --break-system-packages")

    if args.learn:
        print("LEARN MODE — press your remote's button (Ctrl+C to stop)...")
        def on_press(key):
            print(f"  key = {keyname(key)!r}   (use:  --key {keyname(key)})")
        with keyboard.Listener(on_press=on_press) as l:
            l.join()
        return

    target = args.key.lower()
    last = [0.0]
    print(f"1/2 Lens VAR button ready.  Listening for key '{target}'.")
    print(f"Replay endpoint: {args.url}")
    print("Press the button to make a 30s clip.  (Ctrl+C to stop.)")

    def on_press(key):
        if keyname(key) == target:
            now = time.time()
            if now - last[0] < args.debounce:
                return
            last[0] = now
            print(f"[{time.strftime('%H:%M:%S')}] button pressed -> making replay...")
            fire(args.url)

    with keyboard.Listener(on_press=on_press) as l:
        l.join()

if __name__ == "__main__":
    main()