import json
import logging
from typing import Dict, List, Optional, Tuple

import paho.mqtt.client as mqtt

from inverters import Inverter

log = logging.getLogger(__name__)

AGG_DEVICE_ID = "shinebridge_aggregate"
AGG_TOPIC = "shinebridge/aggregate"


class MqttPublisher:
    def __init__(self, broker: str, port: int, user: str, password: str,
                 agg_meta: Optional[Dict] = None):
        self._broker = broker
        self._port = port
        self._connected = False
        self._registered: List[Tuple] = []
        self._agg_meta: Dict = agg_meta or {}

        self._client = mqtt.Client(client_id="shinebridge_hub", clean_session=True)
        if user:
            self._client.username_pw_set(user, password)
        self._client.on_connect = self._on_connect
        self._client.on_disconnect = self._on_disconnect

    def _on_connect(self, client, userdata, flags, rc):
        if rc == 0:
            self._connected = True
            log.info("MQTT verbunden: %s:%d", self._broker, self._port)
            for entry in self._registered:
                self._publish_discovery(*entry)
            if self._agg_meta:
                self._publish_aggregate_discovery()
        else:
            log.error("MQTT Verbindungsfehler rc=%d", rc)

    def _on_disconnect(self, client, userdata, rc):
        self._connected = False
        log.warning("MQTT getrennt rc=%d", rc)

    def connect(self):
        try:
            self._client.connect_async(self._broker, self._port, keepalive=60)
            self._client.loop_start()
        except Exception as e:
            log.error("MQTT connect fehlgeschlagen: %s", e)

    def disconnect(self):
        self._client.loop_stop()
        self._client.disconnect()

    @property
    def connected(self) -> bool:
        return self._connected

    # ── Gerät-Discovery ──────────────────────────────────────

    def register_inverter(self, inverter: Inverter, device_id: str,
                          topic_prefix: str, display_name: str = None):
        entry = (inverter, device_id, topic_prefix, display_name)
        self._registered = [r for r in self._registered if r[1] != device_id]
        self._registered.append(entry)
        if self._connected:
            self._publish_discovery(inverter, device_id, topic_prefix, display_name)

    def unregister_inverter(self, device_id: str):
        self._registered = [r for r in self._registered if r[1] != device_id]

    def _publish_discovery(self, inverter: Inverter, device_id: str,
                           topic_prefix: str, display_name: str = None):
        device_payload = {
            "identifiers": [device_id],
            "name": display_name or inverter.name,
            "manufacturer": inverter.manufacturer,
            "model": inverter.name,
        }
        for sensor in inverter.sensors:
            config = {
                "name": sensor.name,
                "unique_id": f"{device_id}_{sensor.id}",
                "state_topic": f"{topic_prefix}/state",
                "value_template": f"{{{{ value_json.{sensor.id} }}}}",
                "unit_of_measurement": sensor.unit,
                "state_class": sensor.state_class,
                "icon": sensor.icon,
                "device": device_payload,
            }
            if sensor.device_class:
                config["device_class"] = sensor.device_class
            topic = f"homeassistant/sensor/{device_id}/{sensor.id}/config"
            self._client.publish(topic, json.dumps(config), retain=True, qos=1)
        log.info("MQTT Discovery: %d Sensoren für %s", len(inverter.sensors), device_id)

    # ── Aggregat-Discovery ────────────────────────────────────

    def _publish_aggregate_discovery(self):
        device_payload = {
            "identifiers": [AGG_DEVICE_ID],
            "name": "ShineBridge Gesamt",
            "manufacturer": "ShineBridge",
            "model": "Aggregat",
        }
        for sensor_id, meta in self._agg_meta.items():
            config = {
                "name": meta["name"],
                "unique_id": f"{AGG_DEVICE_ID}_{sensor_id}",
                "state_topic": f"{AGG_TOPIC}/state",
                "value_template": f"{{{{ value_json.{sensor_id} }}}}",
                "unit_of_measurement": meta["unit"],
                "state_class": meta["state_class"],
                "icon": meta["icon"],
                "device": device_payload,
            }
            if meta.get("device_class"):
                config["device_class"] = meta["device_class"]
            topic = f"homeassistant/sensor/{AGG_DEVICE_ID}/{sensor_id}/config"
            self._client.publish(topic, json.dumps(config), retain=True, qos=1)
        log.info("MQTT Discovery: %d Aggregat-Sensoren", len(self._agg_meta))

    # ── Daten publizieren ─────────────────────────────────────

    def publish_data(self, values: dict, topic_prefix: str):
        if not self._connected:
            return
        self._client.publish(f"{topic_prefix}/state", json.dumps(values),
                             retain=True, qos=0)

    def publish_status(self, status: str, topic_prefix: str):
        self._client.publish(f"{topic_prefix}/status", status, retain=True, qos=1)

    def publish_aggregates(self, values: dict):
        if not self._connected or not values:
            return
        self._client.publish(f"{AGG_TOPIC}/state", json.dumps(values),
                             retain=True, qos=0)
        self._client.publish(f"{AGG_TOPIC}/status", "online", retain=True, qos=1)