// The sweep-report kind: a cited report that is not yet a video.
//
// It has no decisions, no build and no rich read, which is exactly why it is
// here on day one: it is the cheapest possible proof that adding a kind costs a
// registry entry and nothing else.
import { readdir, readFile, stat } from "node:fs/promises";
import path from "node:path";

const stat0 = (p) => stat(p).then((s) => s, () => null);

const SWEEP_RE = /(^|[-_])sweep([-_]report)?\.md$|^sweep-report\.md$/i;

export async function sweepSignature(dir) {
  const st = await stat0(dir);
  return String(Math.round(st?.mtimeMs ?? 0));
}

export async function summariseSweep(ctx) {
  const { dir, name } = ctx;
  const names = await readdir(dir).catch(() => []);
  const reportName = names.find((n) => SWEEP_RE.test(n));
  const file = reportName ? path.join(dir, reportName) : null;
  const [text, st] = await Promise.all([
    file ? readFile(file, "utf8").catch(() => null) : null,
    file ? stat0(file) : null,
  ]);

  // A citation in these reports is a markdown link carrying a `?v=` moment.
  // Counting them is the one number worth putting on the card: it is how much
  // work a manifest would be.
  const citations = text ? (text.match(/\]\([^)]*[?&]v=/g) ?? []).length : 0;
  const title = text?.match(/^#\s+(.+)$/m)?.[1]?.trim() ?? name;

  const facts = [];
  if (citations) facts.push(`${citations} citation${citations === 1 ? "" : "s"}`);
  facts.push("no manifest");

  return {
    title,
    subtitle: "a report, not yet a video",
    state: "draft",
    newestMtimeMs: st?.mtimeMs ?? 0,
    facts,
    flags: [],
    posterRel: null,
    haystack: [ctx.id, title, reportName].filter(Boolean).join(" ").toLowerCase(),
    reportName,
  };
}