import type { NodeRecord } from "@/lib/types";

// Free disk on the node's host (node-26#41). A full disk stopped node-002
// recording for 17 days while every surface still showed it Online, so low
// space is flagged wherever a node is shown.

export type DiskLevel = "ok" | "low" | "critical";

export interface DiskState {
  level: DiskLevel;
  freePct: number;
  label: string; // e.g. "43.2 GB free of 98 GB (44%)"
}

const LOW_PCT = 15;
const CRITICAL_PCT = 5;
const CRITICAL_BYTES = 2 * 1024 ** 3; // a 2 GB floor regardless of disk size

function gb(bytes: number): string {
  const v = bytes / 1024 ** 3;
  return `${v >= 10 ? v.toFixed(0) : v.toFixed(1)} GB`;
}

/** null when the node has never reported (older node software). */
export function diskState(node: Pick<NodeRecord, "disk_free_bytes" | "disk_total_bytes">): DiskState | null {
  const free = node.disk_free_bytes;
  const total = node.disk_total_bytes;
  if (free == null || !total) return null;
  const freePct = Math.max(0, Math.min(100, (free / total) * 100));
  const level: DiskLevel =
    freePct < CRITICAL_PCT || free < CRITICAL_BYTES ? "critical" : freePct < LOW_PCT ? "low" : "ok";
  return { level, freePct, label: `${gb(free)} free of ${gb(total)} (${Math.round(freePct)}%)` };
}

export const DISK_TEXT_CLASS: Record<DiskLevel, string> = {
  ok: "text-ink-2",
  low: "text-sev-moderate",
  critical: "text-sev-major",
};