// Pure helpers the dashboard and /browse share. NO `node:` import: the state
// strip is rendered on the server but its labels are also what the e2e suite
// compares against /browse's header, and one helper is how the two pages are
// kept from disagreeing by a plural.
import { PROJECT_STATES, type ProjectState } from "./project-types";

/** The header /browse prints and the dashboard's Projects panel repeats. */
export const projectsNote = (total: number, blocking: number, open: number) =>
  `${total} projects · ${blocking} blocking · ${open} open`;

export type StateRow = {
  kind: string;
  label: string;
  total: number;
  /** Every state, in PROJECT_STATES order, zero included -- the strip is proportional. */
  segments: { state: ProjectState; n: number; href: string }[];
};

/** One row per kind: how many projects sit in each of the six states. */
export function stateRows(
  kinds: { id: string; label: string }[],
  projects: { kind: string; state: ProjectState }[],
): StateRow[] {
  return kinds.map((k) => {
    const mine = projects.filter((p) => p.kind === k.id);
    return {
      kind: k.id,
      label: k.label,
      total: mine.length,
      segments: PROJECT_STATES.map((state) => ({
        state,
        n: mine.filter((p) => p.state === state).length,
        href: `/browse?kind=${encodeURIComponent(k.id)}&state=${state}`,
      })),
    };
  });
}

/** Thirty days: the age past which a recorded availability check is "old". */
export const SOURCES_STALE_DAYS = 30;

/**
 * The Sources panel's three buckets, from each report project's summary
 * attributes (report.mjs writes `sources-checked-at`, `sources-dead`,
 * `cue-gaps`). Never checked / checked too long ago / something wrong.
 */
export function sourceBuckets<T extends { id: string; attrs?: Record<string, string> }>(
  projects: T[],
  now = Date.now(),
): { never: T[]; old: T[]; bad: T[] } {
  const never: T[] = [];
  const old: T[] = [];
  const bad: T[] = [];
  for (const p of projects) {
    const a = p.attrs ?? {};
    // Only kinds that report sources at all -- a song has no `sources` attr.
    if (!("sources" in a)) continue;
    if (Number(a.sources) === 0) continue;
    const at = Number(a["sources-checked-at"] ?? 0);
    if (!at) never.push(p);
    else if (now - at > SOURCES_STALE_DAYS * 86_400_000) old.push(p);
    if (Number(a["sources-dead"] ?? 0) > 0 || Number(a["sources-missing"] ?? 0) > 0 || Number(a["cue-gaps"] ?? 0) > 0) {
      bad.push(p);
    }
  }
  return { never, old, bad };
}

export function fmtGB(bytes: number | null): string {
  if (bytes == null) return "–";
  const gb = bytes / 1e9;
  return gb >= 100 ? `${gb.toFixed(0)} GB` : `${gb.toFixed(1)} GB`;
}