#!/usr/bin/env python3
"""Simuliert eine go-e-Wallbox-Ladung über MQTT, um den Collector zu testen.

Sendet nacheinander:
    car=2  (Start)  ->  wh  ->  cdi  ->  car=4 (Ende)

Broker/User/Topic werden – wie beim Collector – aus der .env gelesen.

Beispiele:
    .venv/bin/python collector/sim_charge.py                 # 5230 Wh, 3600 s
    .venv/bin/python collector/sim_charge.py --wh 8000 --duration 5400
    .venv/bin/python collector/sim_charge.py --end idle      # mit car=1 beenden
    .venv/bin/python collector/sim_charge.py --no-finish     # Session offen lassen
"""

import argparse
import json
import os
import sys
import time

import paho.mqtt.client as mqtt
from dotenv import load_dotenv

load_dotenv()

MQTT_HOST = os.environ.get("MQTT_HOST", "localhost")
MQTT_PORT = int(os.environ.get("MQTT_PORT", "1883"))
MQTT_USER = os.environ.get("MQTT_USER") or None
MQTT_PASS = os.environ.get("MQTT_PASS") or None
TOPIC_BASE = os.environ.get("MQTT_TOPIC_BASE", "go-eCharger/310014").rstrip("/")


def parse_args() -> argparse.Namespace:
    p = argparse.ArgumentParser(description="Test-Ladung über MQTT simulieren")
    p.add_argument("--wh", type=float, default=5230.5, help="geladene Energie in Wh")
    p.add_argument("--duration", type=int, default=3600, help="Ladedauer in Sekunden")
    p.add_argument("--end", choices=["complete", "idle"], default="complete",
                   help="Abschluss über car=4 (complete) oder car=1 (idle)")
    p.add_argument("--no-finish", action="store_true",
                   help="Session nicht abschließen (kein car=1/4 senden)")
    p.add_argument("--delay", type=float, default=0.7,
                   help="Pause zwischen den Nachrichten in Sekunden")
    return p.parse_args()


def main() -> int:
    args = parse_args()

    client = mqtt.Client(
        callback_api_version=mqtt.CallbackAPIVersion.VERSION2,
        client_id="auto-charger-sim",
    )
    if MQTT_USER:
        client.username_pw_set(MQTT_USER, MQTT_PASS)

    print(f"Verbinde zu {MQTT_HOST}:{MQTT_PORT} (Topic-Basis {TOPIC_BASE}) ...")
    try:
        client.connect(MQTT_HOST, MQTT_PORT, keepalive=60)
    except OSError as exc:
        print(f"FEHLER: Verbindung zum Broker fehlgeschlagen: {exc}")
        return 1
    client.loop_start()

    end_car = 4 if args.end == "complete" else 1
    steps: list[tuple[str, str]] = [
        ("car", "2"),
        ("wh", f"{args.wh}"),
        ("cdi", json.dumps({"type": 1, "value": args.duration * 1000})),
    ]
    if not args.no_finish:
        steps.append(("car", str(end_car)))

    for key, payload in steps:
        topic = f"{TOPIC_BASE}/{key}"
        info = client.publish(topic, payload, qos=1)
        info.wait_for_publish(timeout=5)
        print(f"  -> {topic} = {payload}")
        time.sleep(args.delay)

    client.loop_stop()
    client.disconnect()
    print("Fertig. Erwartete Collector-Ausgabe: 'Ladung gestartet ...' "
          "und 'Ladung gespeichert: %.0f Wh, %d s'." % (args.wh, args.duration))
    return 0


if __name__ == "__main__":
    try:
        sys.exit(main())
    except KeyboardInterrupt:
        sys.exit(0)