#!/home/noise/.local/share/uv/tools/powermon/bin/python
"""eg4-purge-orphans — remove deprecated HA-discovery entities from MQTT.

After we drop fields from the daemon's published set (raw register_NN, the
superseded bms_version_hi/lo u16s, the noisy uptime_ds counter, etc.), the
old discovery configs remain RETAINED in the broker — so HA keeps the
orphaned entities forever.

This tool publishes an empty payload (with retain=true) to each orphaned
config topic, which tells HA "forget this entity" and clears the broker's
retained slot.

Idempotent + safe to re-run. Doesn't touch live entities (those get
re-published by the daemon every cycle).

Usage:
    eg4-purge-orphans <broker> <user> <password> [--dry-run]
"""
from __future__ import annotations
import sys
import argparse
import paho.mqtt.client as mqtt

PACK_NAMES = ["lifepower4_1", "lifepower4_2", "lifepower4_3"]

# Build the topic list to purge.
DEPRECATED_KEYS: list[str] = []
for n in range(0, 136):
    DEPRECATED_KEYS.append(f"register_{n:02d}")    # 136 raw register entities
DEPRECATED_KEYS.append("bms_version_hi")            # superseded by firmware_version
DEPRECATED_KEYS.append("bms_version_lo")            # superseded by firmware_version
DEPRECATED_KEYS.append("uptime_ds")                 # noisy counter

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: list[str] = []
    for pack in PACK_NAMES:
        for key in DEPRECATED_KEYS:
            topics.append(f"{PREFIX}/{pack}_{key}/config")

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

    if args.dry_run:
        for t in topics[:5]:
            print(f"  (dry-run) {t}")
        print(f"  ... and {len(topics) - 5} more")
        return 0

    # Use legacy constructor — works on both paho-mqtt 1.x and 2.x
    try:
        c = mqtt.Client(mqtt.CallbackAPIVersion.VERSION2, client_id="eg4-purge")
    except AttributeError:
        c = mqtt.Client(client_id="eg4-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):
            info = c.publish(t, payload="", qos=0, retain=True)
            info.wait_for_publish(2)
            if (i + 1) % 50 == 0:
                print(f"  ...{i + 1}/{len(topics)}")
        print(f"done — {len(topics)} retained configs cleared")
    finally:
        c.loop_stop()
        c.disconnect()
    return 0


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