# MQTT subscriber that reads weather data and stores in PostgreSQL

import os
import json
import logging
import ssl
from datetime import datetime
from pathlib import Path
from dotenv import load_dotenv
import paho.mqtt.client as mqtt
import psycopg2
from psycopg2.extras import RealDictCursor

# Logging konfigurieren
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(levelname)s - %(message)s'
)
logger = logging.getLogger(__name__)

# Umgebungsvariablen laden - eine Ebene höher
env_path = Path(__file__).parent.parent / '.env'
load_dotenv(dotenv_path=env_path)

# Konfiguration
MQTT_BROKER = os.getenv('MQTT_BROKER', 'rexfue.de')
MQTT_PORT = int(os.getenv('MQTT_PORT', 1883))
MQTT_USERNAME = os.getenv('MQTT_USERNAME')
MQTT_PASSWORD = os.getenv('MQTT_PASSWORD')
MQTT_TOPIC = os.getenv('MQTT_TOPIC', 'vantage/live')

DB_HOST = os.getenv('DB_HOST', 'localhost')
DB_PORT = int(os.getenv('DB_PORT', 5432))
DB_NAME = os.getenv('DB_NAME', 'wetterstation')
DB_USER = os.getenv('DB_USER')
DB_PASSWORD = os.getenv('DB_PASSWORD')


class WeatherDataCollector:
    """Klasse zum Sammeln und Speichern von Wetterdaten aus MQTT in PostgreSQL"""
    
    def __init__(self):
        self.db_conn = None
        self.mqtt_client = None
        self.setup_database()
        self.setup_mqtt()
    
    def setup_database(self):
        """Datenbankverbindung herstellen und Tabelle erstellen"""
        try:
            self.db_conn = psycopg2.connect(
                host=DB_HOST,
                port=DB_PORT,
                database=DB_NAME,
                user=DB_USER,
                password=DB_PASSWORD
            )
            logger.info("Datenbankverbindung hergestellt")
            
            # Tabelle erstellen falls nicht vorhanden
            with self.db_conn.cursor() as cursor:
                cursor.execute("""
                    CREATE TABLE IF NOT EXISTS weather_data (
                        id SERIAL PRIMARY KEY,
                        datetime TIMESTAMP NOT NULL,
                        temperature FLOAT,
                        humidity INTEGER,
                        pressure FLOAT,
                        wind_speed FLOAT,
                        wind_gust FLOAT,
                        wind_dir FLOAT,
                        rain FLOAT,
                        rain_rate FLOAT,
                        received_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
                        UNIQUE(datetime)
                    )
                """)
                self.db_conn.commit()
                logger.info("Tabelle weather_data bereit")
        except Exception as e:
            logger.error(f"Fehler bei Datenbankverbindung: {e}")
            raise
    
    def setup_mqtt(self):
        """MQTT Client konfigurieren"""
        self.mqtt_client = mqtt.Client()
        self.mqtt_client.username_pw_set(MQTT_USERNAME, MQTT_PASSWORD)
        
        # Callbacks setzen
        self.mqtt_client.on_connect = self.on_connect
        self.mqtt_client.on_message = self.on_message
        self.mqtt_client.on_disconnect = self.on_disconnect
        
        logger.info(f"MQTT Client konfiguriert für {MQTT_BROKER}:{MQTT_PORT}")
    
    def on_connect(self, client, userdata, flags, rc):
        """Callback wenn MQTT Verbindung hergestellt wird"""
        if rc == 0:
            logger.info("Mit MQTT Broker verbunden")
            client.subscribe(MQTT_TOPIC)
            logger.info(f"Topic abonniert: {MQTT_TOPIC}")
        else:
            logger.error(f"Verbindung fehlgeschlagen mit Code {rc}")
    
    def on_disconnect(self, client, userdata, rc):
        """Callback wenn MQTT Verbindung getrennt wird"""
        if rc != 0:
            logger.warning(f"Unerwartete Trennung vom Broker. Code: {rc}")
    
    def on_message(self, client, userdata, msg):
        """Callback wenn MQTT Nachricht empfangen wird"""
        try:
            payload = msg.payload.decode('utf-8')
            logger.info(f"Nachricht empfangen auf {msg.topic}: {payload}")
            
            # JSON parsen
            data = json.loads(payload)
            
            # In Datenbank speichern
            self.save_to_database(data)
            
        except json.JSONDecodeError as e:
            logger.error(f"Fehler beim JSON-Parsen: {e}")
        except Exception as e:
            logger.error(f"Fehler bei Nachrichtenverarbeitung: {e}")
    
    def save_to_database(self, data):
        """Wetterdaten in PostgreSQL speichern"""
        try:
            with self.db_conn.cursor() as cursor:
                cursor.execute("""
                    INSERT INTO weather_data 
                    (datetime, temperature, humidity, pressure, wind_speed, 
                     wind_gust, wind_dir, rain, rain_rate)
                    VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s)
                    ON CONFLICT (datetime) DO UPDATE SET
                        temperature = EXCLUDED.temperature,
                        humidity = EXCLUDED.humidity,
                        pressure = EXCLUDED.pressure,
                        wind_speed = EXCLUDED.wind_speed,
                        wind_gust = EXCLUDED.wind_gust,
                        wind_dir = EXCLUDED.wind_dir,
                        rain = EXCLUDED.rain,
                        rain_rate = EXCLUDED.rain_rate
                """, (
                    data.get('datetime'),
                    data.get('temperature'),
                    data.get('humidity'),
                    data.get('pressure'),
                    data.get('wind_speed'),
                    data.get('wind_gust'),
                    data.get('wind_dir'),
                    data.get('rain'),
                    data.get('rain_rate')
                ))
                self.db_conn.commit()
                logger.info(f"Daten gespeichert für {data.get('datetime')}")
        except Exception as e:
            logger.error(f"Fehler beim Speichern in Datenbank: {e}")
            self.db_conn.rollback()
    
    def start(self):
        """MQTT Client starten und auf Nachrichten warten"""
        try:
            self.mqtt_client.connect(MQTT_BROKER, MQTT_PORT, 60)
            logger.info("Starte MQTT Loop...")
            self.mqtt_client.loop_forever()
        except KeyboardInterrupt:
            logger.info("Programm wird beendet...")
        except Exception as e:
            logger.error(f"Fehler beim Start: {e}")
        finally:
            self.cleanup()
    
    def cleanup(self):
        """Ressourcen aufräumen"""
        if self.mqtt_client:
            self.mqtt_client.disconnect()
            logger.info("MQTT Verbindung getrennt")
        if self.db_conn:
            self.db_conn.close()
            logger.info("Datenbankverbindung geschlossen")


def main():
    """Hauptfunktion"""
    logger.info("Wetterstation Collector startet...")
    
    # Prüfen ob alle nötigen Umgebungsvariablen gesetzt sind
    required_vars = ['MQTT_USERNAME', 'MQTT_PASSWORD', 'DB_USER', 'DB_PASSWORD']
    missing_vars = [var for var in required_vars if not os.getenv(var)]
    
    if missing_vars:
        logger.error(f"Fehlende Umgebungsvariablen: {', '.join(missing_vars)}")
        logger.error("Bitte .env Datei mit den erforderlichen Werten erstellen")
        return
    
    collector = WeatherDataCollector()
    collector.start()


if __name__ == "__main__":
    main()