import json
import logging
import os
from typing import Any, Dict

from flask import Flask, jsonify, render_template, request
import paho.mqtt.client as mqtt


MQTT_HOST = os.getenv("MQTT_HOST", "127.0.0.1")
MQTT_PORT = int(os.getenv("MQTT_PORT", "1883"))
MQTT_USER = os.getenv("MQTT_USER", "")
MQTT_PASSWORD = os.getenv("MQTT_PASSWORD", "")
MQTT_BASE_TOPIC = os.getenv("MQTT_BASE_TOPIC", "evs")
PORTAL_BIND_HOST = os.getenv("PORTAL_BIND_HOST", "0.0.0.0")
PORTAL_BIND_PORT = int(os.getenv("PORTAL_BIND_PORT", "8088"))
LOG_LEVEL = os.getenv("LOG_LEVEL", "INFO")


logging.basicConfig(level=LOG_LEVEL, format="%(asctime)s %(levelname)s %(message)s")
log = logging.getLogger("evs-control-portal")

app = Flask(__name__)
mqtt_connected = False
mqtt_client = mqtt.Client(mqtt.CallbackAPIVersion.VERSION2, client_id="evs-control-portal")
if MQTT_USER:
    mqtt_client.username_pw_set(MQTT_USER, MQTT_PASSWORD)


def _on_connect(_client, _userdata, _flags, reason_code, _properties=None):
    global mqtt_connected
    mqtt_connected = reason_code == 0
    if mqtt_connected:
        log.info("mqtt connected: %s:%s", MQTT_HOST, MQTT_PORT)
    else:
        log.error("mqtt connect failed: reason_code=%s", reason_code)


def _on_disconnect(_client, _userdata, reason_code, _properties=None):
    global mqtt_connected
    mqtt_connected = False
    log.warning("mqtt disconnected: reason_code=%s", reason_code)


mqtt_client.on_connect = _on_connect
mqtt_client.on_disconnect = _on_disconnect
mqtt_client.connect_async(MQTT_HOST, MQTT_PORT, keepalive=30)
mqtt_client.loop_start()


def _topic_for_device(device_id: str) -> str:
    return f"{MQTT_BASE_TOPIC}/{device_id}/command"


def _publish(device_id: str, payload: Dict[str, Any]) -> Dict[str, Any]:
    if not mqtt_connected:
        return {
            "ok": False,
            "error": f"mqtt not connected to {MQTT_HOST}:{MQTT_PORT}",
            "mqtt_connected": False,
        }
    topic = _topic_for_device(device_id)
    encoded = json.dumps(payload, separators=(",", ":"))
    info = mqtt_client.publish(topic, encoded, qos=0, retain=False)
    return {
        "ok": info.rc == mqtt.MQTT_ERR_SUCCESS,
        "topic": topic,
        "payload": payload,
        "mqtt_rc": info.rc,
        "mqtt_connected": mqtt_connected,
    }


@app.get("/")
def index():
    return render_template("index.html", mqtt_host=MQTT_HOST, mqtt_port=MQTT_PORT, base_topic=MQTT_BASE_TOPIC)


@app.post("/api/publish")
def api_publish():
    body = request.get_json(force=True, silent=True) or {}
    device_id = str(body.get("device_id", "")).strip()
    payload = body.get("payload")
    if not device_id:
        return jsonify({"ok": False, "error": "device_id is required"}), 400
    if not isinstance(payload, dict):
        return jsonify({"ok": False, "error": "payload must be a JSON object"}), 400
    return jsonify(_publish(device_id, payload))


if __name__ == "__main__":
    app.run(host=PORTAL_BIND_HOST, port=PORTAL_BIND_PORT, debug=False)