#!/usr/bin/env python3
"""
Shelly RGBW2 Animator Service
-----------------------------
Listens on MQTT for animation commands and drives the Shelly directly
via its HTTP API.  Designed to run as a lightweight Docker container
or systemd service on a Raspberry Pi.

MQTT topics (configurable):
  <prefix>/set      – write: animation name or "stop" / "off"
  <prefix>/state    – read:  current animation name or "off"

Example:
  mosquitto_pub -t shelly-animator/set -m "party"
  mosquitto_pub -t shelly-animator/set -m "stop"
"""

from __future__ import annotations

import logging
import os
import signal
import sys
import threading
import time

import paho.mqtt.client as mqtt

from animations import REGISTRY, get_animation_class
from shelly import ShellyRGBW2

# ---------------------------------------------------------------------------
# Config from environment
# ---------------------------------------------------------------------------
SHELLY_HOST = os.getenv("SHELLY_HOST", "192.168.178.151")
SHELLY_USER = os.getenv("SHELLY_USER", "shelly@till.immers.ch")
SHELLY_PASS = os.getenv("SHELLY_PASS", "sh3llyTi33*")

MQTT_HOST = os.getenv("MQTT_HOST", "localhost")
MQTT_PORT = int(os.getenv("MQTT_PORT", "1884"))
MQTT_USER = os.getenv("MQTT_USER", "")
MQTT_PASS = os.getenv("MQTT_PASS", "")
MQTT_PREFIX = os.getenv("MQTT_PREFIX", "shelly-animator")

LOG_LEVEL = os.getenv("LOG_LEVEL", "INFO").upper()

logging.basicConfig(
    level=getattr(logging, LOG_LEVEL, logging.INFO),
    format="%(asctime)s [%(levelname)s] %(name)s: %(message)s",
    datefmt="%H:%M:%S",
)
log = logging.getLogger("main")

# ---------------------------------------------------------------------------
# Runtime state
# ---------------------------------------------------------------------------
shelly = ShellyRGBW2(SHELLY_HOST, SHELLY_USER, SHELLY_PASS)
current_anim = None  # type: ignore
lock = threading.Lock()


def stop_current() -> None:
    global current_anim
    with lock:
        if current_anim and current_anim.running:
            current_anim.stop()
        current_anim = None


def start_animation(name: str) -> bool:
    global current_anim
    cls = get_animation_class(name)
    if cls is None:
        log.warning("Unknown animation: %s  (available: %s)", name, list(REGISTRY))
        return False

    with lock:
        if current_anim and current_anim.running:
            if current_anim.name == cls.name:
                log.info("Animation '%s' already running", cls.name)
                return True
            current_anim.stop()

        anim = cls(shelly)
        anim.start()
        current_anim = anim
    return True


def publish_state(client: mqtt.Client) -> None:
    state = "off"
    with lock:
        if current_anim and current_anim.running:
            state = current_anim.name
    client.publish(f"{MQTT_PREFIX}/state", state, retain=True)


# ---------------------------------------------------------------------------
# MQTT callbacks
# ---------------------------------------------------------------------------
def on_connect(client: mqtt.Client, userdata, flags, reason_code, properties=None):
    log.info("MQTT connected (rc=%s)", reason_code)
    client.subscribe(f"{MQTT_PREFIX}/set")
    publish_state(client)


def on_message(client: mqtt.Client, userdata, msg: mqtt.MQTTMessage):
    payload = msg.payload.decode("utf-8", errors="ignore").strip()
    log.info("MQTT command: %s", payload)

    if payload.lower() in ("stop", "off", "none", ""):
        stop_current()
        publish_state(client)
        return

    if start_animation(payload):
        publish_state(client)
    else:
        log.warning("Ignored unknown command: %s", payload)


# ---------------------------------------------------------------------------
# Main
# ---------------------------------------------------------------------------
def main() -> None:
    log.info("Shelly Animator starting")
    log.info("  Shelly : %s", SHELLY_HOST)
    log.info("  MQTT   : %s:%s  prefix=%s", MQTT_HOST, MQTT_PORT, MQTT_PREFIX)
    log.info("  Anims  : %s", ", ".join(sorted(set(c.name for c in REGISTRY.values()))))

    client = mqtt.Client(
        mqtt.CallbackAPIVersion.VERSION2,
        client_id="shelly-animator",
    )
    if MQTT_USER:
        client.username_pw_set(MQTT_USER, MQTT_PASS)

    client.on_connect = on_connect
    client.on_message = on_message

    # Graceful shutdown
    def shutdown(signum, frame):
        log.info("Shutting down...")
        stop_current()
        client.disconnect()
        sys.exit(0)

    signal.signal(signal.SIGTERM, shutdown)
    signal.signal(signal.SIGINT, shutdown)

    while True:
        try:
            client.connect(MQTT_HOST, MQTT_PORT, keepalive=60)
            client.loop_forever()
        except Exception as exc:
            log.error("MQTT connection error: %s – retry in 5s", exc)
            time.sleep(5)


if __name__ == "__main__":
    main()