#!/usr/bin/env python3
"""lvx-purge-orphans — remove deprecated HA-discovery entities from MQTT.

After the powermon-patches (g) cleanup + GS excl_filter additions:
  - several fields are no longer published (always-zero / dead on this hardware)
  - one entity got renamed (dc-ac_power_direction → dc_ac_power_direction)

This tool publishes empty retained payloads to those orphan config topics so
HA forgets the entities cleanly.

Idempotent. Compatible with paho-mqtt 1.x and 2.x.

Usage:
    lvx-purge-orphans <broker> <user> <password> [--dry-run]
"""
from __future__ import annotations
import sys
import argparse
import paho.mqtt.client as mqtt

INVERTERS = ["lvx6048_1", "lvx6048_2"]

# Keys that disappeared from publication after this cleanup pass.
DEPRECATED_KEYS: list[str] = [
    "battery_voltage_from_scc",
    "battery_voltage_from_scc2",
    "mppt2_charger_temperature",
    "mppt2_charger_status",
    "mppt2_input_power",
    "mppt2_input_voltage",
    "setting_value_configuration_state",
    "dc-ac_power_direction",   # renamed → dc_ac_power_direction
]

PREFIX = "homeassistant/sensor"


def main() -> int:
    ap = argparse.ArgumentParser()
    ap.add_argument("host")
    ap.add_argument("user")
    ap.add_argument("password")
    ap.add_argument("--dry-run", action="store_true",
                    help="print topics that would be purged, don't publish")
    ap.add_argument("--port", type=int, default=1883)
    args = ap.parse_args()

    topics = [f"{PREFIX}/{inv}_{key}/config"
              for inv in INVERTERS for key in DEPRECATED_KEYS]

    print(f"will purge {len(topics)} topic(s) "
          f"({len(DEPRECATED_KEYS)} keys × {len(INVERTERS)} inverters)")

    if args.dry_run:
        for t in topics:
            print(f"  (dry-run) {t}")
        return 0

    try:
        c = mqtt.Client(mqtt.CallbackAPIVersion.VERSION2, client_id="lvx-purge")
    except AttributeError:
        c = mqtt.Client(client_id="lvx-purge")
    c.username_pw_set(args.user, args.password)
    c.connect(args.host, args.port, keepalive=30)
    c.loop_start()
    try:
        for i, t in enumerate(topics, start=1):
            info = c.publish(t, payload="", qos=0, retain=True)
            info.wait_for_publish(2)
            print(f"  {i:>3}/{len(topics)}  {t}")
        print(f"done — {len(topics)} retained configs cleared")
    finally:
        c.loop_stop()
        c.disconnect()
    return 0


if __name__ == "__main__":
    sys.exit(main())