"""Unraid servers status router."""

from __future__ import annotations

import logging
from typing import Any, Dict, List

from fastapi import APIRouter

from server.cache import cache
from server.config import get_settings
from server.services.mqtt_service import mqtt_service
from server.services.unraid_service import ServerConfig, fetch_all_servers

logger = logging.getLogger(__name__)

router = APIRouter(prefix="/api", tags=["servers"])

CACHE_KEY = "servers"


# ---------------------------------------------------------------------------
# MQTT enrichment — overlay live system metrics from MQTT topics
# ---------------------------------------------------------------------------

def _enrich_from_mqtt(servers: List[Dict[str, Any]]) -> None:
    """Merge live CPU/RAM data from MQTT ``<prefix>/system`` topics.

    The Unraid MQTT Agent plugin publishes JSON payloads to topics like
    ``unraid-daddelolymp/system`` or ``Adriahub/system`` every ~15 s.
    These contain live ``cpu_usage_percent``, ``ram_usage_percent``, etc.
    that the GraphQL API does not expose.
    """

    store = mqtt_service.store

    for srv in servers:
        name = srv.get("name", "")
        if not name:
            continue

        # Try common topic patterns
        system_data: Dict[str, Any] | None = None
        for pattern in (
            f"{name}/system",                          # "Adriahub/system"
            f"unraid-{name.lower()}/system",           # "unraid-daddelolymp/system"
            f"unraid-{name}/system",                   # "unraid-Daddelolymp/system"
        ):
            msg = store.get(pattern)
            if msg is not None and isinstance(msg.payload, dict):
                system_data = msg.payload
                break

        if not system_data:
            continue

        # --- CPU ---
        cpu_pct = system_data.get("cpu_usage_percent")
        if cpu_pct is not None:
            srv["cpu"]["usage_pct"] = round(float(cpu_pct), 1)

        cpu_model = system_data.get("cpu_model")
        if cpu_model:
            srv["cpu"]["brand"] = cpu_model

        cpu_temp = system_data.get("cpu_temp_celsius")
        if cpu_temp is not None:
            srv["cpu"]["temp_c"] = cpu_temp

        cores = system_data.get("cpu_cores")
        if cores:
            srv["cpu"]["cores"] = cores

        threads = system_data.get("cpu_threads")
        if threads:
            srv["cpu"]["threads"] = threads

        # --- RAM ---
        ram_pct = system_data.get("ram_usage_percent")
        if ram_pct is not None:
            srv["ram"]["pct"] = round(float(ram_pct), 1)

        ram_total = system_data.get("ram_total_bytes")
        if ram_total:
            srv["ram"]["total_gb"] = round(ram_total / (1024 ** 3), 1)

        ram_used = system_data.get("ram_used_bytes")
        if ram_used:
            srv["ram"]["used_gb"] = round(ram_used / (1024 ** 3), 1)

        # --- Uptime ---
        uptime_secs = system_data.get("uptime_seconds")
        if uptime_secs:
            days = uptime_secs // 86400
            hours = (uptime_secs % 86400) // 3600
            srv["uptime"] = f"{days}d {hours}h"

        srv["online"] = True

        logger.debug(
            "[UNRAID] %s: MQTT enriched — CPU %.1f%% %.0f°C, RAM %.1f%%",
            name,
            srv["cpu"].get("usage_pct", 0),
            srv["cpu"].get("temp_c", 0) or 0,
            srv["ram"].get("pct", 0),
        )


@router.get("/servers")
async def get_servers() -> Dict[str, Any]:
    """Return status information for all configured Unraid servers.

    Response shape::

        {
            "servers": [ ... server dicts ... ]
        }
    """

    # --- cache hit? -----------------------------------------------------------
    cached = await cache.get(CACHE_KEY)
    if cached is not None:
        # Always overlay fresh MQTT data even on cache hits
        _enrich_from_mqtt(cached.get("servers", []))
        return cached

    # --- cache miss -----------------------------------------------------------
    server_configs: List[ServerConfig] = [
        ServerConfig(
            name=srv.name,
            host=srv.host,
            api_key=srv.api_key,
            port=srv.port,
        )
        for srv in get_settings().unraid_servers
    ]

    servers_data: List[Dict[str, Any]] = []
    try:
        servers_data = await fetch_all_servers(server_configs)
    except Exception as exc:
        logger.exception("Failed to fetch Unraid server data")
        return {
            "servers": [],
            "error": True,
            "message": str(exc),
        }

    # Overlay live MQTT system metrics
    _enrich_from_mqtt(servers_data)

    payload: Dict[str, Any] = {
        "servers": servers_data,
    }

    await cache.set(CACHE_KEY, payload, get_settings().unraid_cache_ttl)
    return payload