#!/usr/bin/env python3
"""
Push state/commands to a WLED device.
Accepts a JSON file or simple flags (on, off, bri, preset).
Uses only standard library (no pip install).
"""
import argparse
import json
import sys
from typing import Optional
from urllib.request import Request, urlopen
from urllib.error import URLError, HTTPError

DEFAULT_HOST = "192.168.240.30"


def push(host: str, payload: dict, return_state: bool = False) -> Optional[dict]:
    base = host if host.startswith("http") else f"http://{host}"
    url = f"{base}/json/state"

    if return_state:
        payload["v"] = True

    body = json.dumps(payload).encode("utf-8")
    req = Request(
        url,
        data=body,
        method="POST",
        headers={"Content-Type": "application/json", "Accept": "application/json"},
    )
    try:
        with urlopen(req, timeout=10) as r:
            raw = r.read().decode()
            if not raw:
                return None
            return json.loads(raw)
    except HTTPError as e:
        print(f"HTTP error: {e.code} {e.reason}", file=sys.stderr)
        if e.fp:
            print(e.fp.read().decode(), file=sys.stderr)
        sys.exit(1)
    except URLError as e:
        print(f"Request failed: {e.reason}", file=sys.stderr)
        sys.exit(1)
    except json.JSONDecodeError as e:
        print(f"Invalid response JSON: {e}", file=sys.stderr)
        sys.exit(1)


def main():
    p = argparse.ArgumentParser(description="Push state/commands to WLED")
    p.add_argument("--host", "-H", default=DEFAULT_HOST, help=f"WLED host (default: {DEFAULT_HOST})")
    p.add_argument("--file", "-f", metavar="JSON", help="JSON file with state to send")
    p.add_argument("--on", action="store_true", help="Turn on")
    p.add_argument("--off", action="store_true", help="Turn off")
    p.add_argument("--toggle", "-t", action="store_true", dest="toggle", help="Toggle on/off")
    p.add_argument("--bri", type=int, metavar="0-255", help="Brightness")
    p.add_argument("--preset", "-p", type=int, metavar="ID", help="Load preset by ID")
    p.add_argument("--v", action="store_true", help="Return full state in response")
    args = p.parse_args()

    if args.file:
        with open(args.file) as f:
            payload = json.load(f)
    else:
        payload = {}

    if args.off:
        payload["on"] = False
    if args.on:
        payload["on"] = True
    if args.toggle:
        payload["on"] = "t"
    if args.bri is not None:
        payload["bri"] = max(0, min(255, args.bri))
    if args.preset is not None:
        payload["ps"] = args.preset
    if args.v:
        payload["v"] = True

    if not payload:
        print("Nothing to send. Use --file, --on, --off, --toggle, --bri, or --preset.", file=sys.stderr)
        sys.exit(1)

    out = push(args.host, payload, return_state=args.v)
    if out:
        print(json.dumps(out, indent=2))


if __name__ == "__main__":
    main()