"""Statuts du NAS via le moniteur maison `nas_monitor` (`GET /api/status`).

Expose : occupation des disques de données (`/mnt/*`), santé des conteneurs Docker,
et l'état du port forwardé entre gluetun (VPN) et qBittorrent.
"""
from __future__ import annotations

from dataclasses import dataclass, field

import httpx

from config import config


@dataclass
class NasDisk:
    label: str
    percent: float
    free_gb: float

    @property
    def free_human(self) -> str:
        if self.free_gb >= 1024:
            return f"{self.free_gb / 1024:.1f}".replace(".", ",") + " To"
        return f"{self.free_gb:.0f} Go"


@dataclass
class NasStatus:
    ok: bool
    error: str | None = None
    disks: list[NasDisk] = field(default_factory=list)
    docker_running: int = 0
    docker_total: int = 0
    docker_unhealthy: int = 0
    vpn_port: int | None = None
    vpn_ok: bool = False


def _disk_label(mount: str) -> str:
    """`/mnt/disk1` -> `Disque 1`, sinon le dernier segment capitalisé."""
    base = mount.rstrip("/").split("/")[-1]
    if base.startswith("disk"):
        return "Disque " + base[len("disk"):]
    return base.capitalize() or mount


def _as_int(value: object) -> int | None:
    try:
        return int(value)  # type: ignore[arg-type]
    except (TypeError, ValueError):
        return None


async def fetch_status() -> NasStatus:
    if not config.nas_url:
        return NasStatus(ok=False, error="NAS désactivé")

    try:
        async with httpx.AsyncClient(timeout=15) as client:
            resp = await client.get(config.nas_url)
        if resp.status_code != 200:
            return NasStatus(ok=False, error=f"HTTP {resp.status_code}")
        data = resp.json()
    except httpx.HTTPError:
        return NasStatus(ok=False, error="injoignable")

    metrics = (data.get("host") or {}).get("metrics") or {}
    disks: list[NasDisk] = []
    for disk in metrics.get("disks") or []:
        mount = str(disk.get("mount", ""))
        if not mount.startswith("/mnt"):  # on ne garde que les disques de données
            continue
        disks.append(NasDisk(
            label=_disk_label(mount),
            percent=float(disk.get("percent", 0) or 0),
            free_gb=float(disk.get("free_gb", 0) or 0),
        ))

    summary = (data.get("docker") or {}).get("summary") or {}

    # Port VPN : OK quand le port forwardé par gluetun == port d'écoute qBittorrent.
    qb = data.get("qbittorrent") or {}
    listen = _as_int((qb.get("prefs") or {}).get("listen_port"))
    fwd = _as_int(qb.get("forwarded_port_file"))
    vpn_ok = listen is not None and fwd is not None and listen == fwd

    return NasStatus(
        ok=True,
        disks=disks,
        docker_running=int(summary.get("running", 0) or 0),
        docker_total=int(summary.get("total", 0) or 0),
        docker_unhealthy=int(summary.get("unhealthy", 0) or 0),
        vpn_port=fwd if fwd is not None else listen,
        vpn_ok=vpn_ok,
    )