// BidaAngMamamayan feed read path — the public edition.
//
// No profiles, no learning, no LLM. The ranking is deliberate and
// deterministic: stories that NAME Sen. Bam lead; within each tier, freshness
// decides. This is a tribute site, not a taste engine — the "taste" is baked
// in by the crawler's relevance gate.
import { getCollections } from "./db.js";
import { normalizeCategory, sectionName, CATEGORY_LABELS, CATEGORIES } from "./categories.js";

export { sectionName };

const POOL_HOURS = 24 * 14; // the site's memory window for the edition

// Simple, stable score: named-BAM beats context, fresh beats old, image
// presence nudges a card up (a photoless tribute edition looks broken).
function rank(s, nowMs) {
  let score = 0;
  if (s.named) score += 1000;
  if (s.image) score += 50;
  const ageH = (nowMs - new Date(s.published || s.discoveredAt || 0).getTime()) / 3600e3;
  if (Number.isFinite(ageH)) score += Math.max(0, 100 - ageH); // 0..100, decaying
  return score;
}

function shape(s) {
  return {
    url: s.url,
    title: s.title,
    summary: s.summary,
    image: s.image || null,
    source: s.source,
    category: normalizeCategory(s.category),
    desk: s.desk || null,
    published: s.published,
    discoveredAt: s.discoveredAt,
    named: !!s.named,
    fallback: !!s.fallback,
    score: 0,
    feedKind: s.feedKind || "native",
  };
}

export async function getFeed({ limit = 60 } = {}) {
  const { stories } = await getCollections();
  const now = new Date();
  const rows = await stories
    .find({
      discoveredAt: { $gte: new Date(now.getTime() - POOL_HOURS * 3600e3) },
      desk: { $ne: "system" },
    })
    .sort({ discoveredAt: -1 })
    .limit(1000)
    .toArray();

  const nowMs = now.getTime();
  const items = rows
    .map((s) => {
      const it = shape(s);
      it.score = rank(s, nowMs);
      return it;
    })
    .sort((a, b) => b.score - a.score || new Date(b.published || b.discoveredAt || 0) - new Date(a.published || a.discoveredAt || 0))
    .slice(0, limit);

  return {
    items,
    generatedAt: now,
    mode: "public",
    ranked: true,
    // masthead counts
    named: rows.filter((s) => s.named).length,
    total: rows.length,
  };
}

// One (or a few) headline(s) per desk, straight from the pool — the front
// page's desk grid is built from this, exactly as forthena's was. Zero LLM.
export async function deskHeadlines() {
  try {
    const { stories } = await getCollections();
    const nowMs = Date.now();
    const rows = await stories
      .find({
        discoveredAt: { $gte: new Date(nowMs - POOL_HOURS * 3600e3) },
        desk: { $ne: "system" },
      })
      .limit(2000)
      .toArray();
    const per = new Map();
    const count = new Map();
    for (const s of rows) {
      const cat = normalizeCategory(s.category);
      count.set(cat, (count.get(cat) || 0) + 1);
      const it = shape(s);
      it.score = rank(s, nowMs);
      const arr = per.get(cat) || [];
      arr.push(it);
      per.set(cat, arr);
    }
    return CATEGORIES
      .map((c) => {
        const arr = (per.get(c.key) || []).sort((a, b) => b.score - a.score);
        if (!arr.length) return null;
        return { key: c.key, label: sectionName(c.key), blurb: c.blurb || "", count: count.get(c.key) || arr.length, stories: arr.slice(0, 12) };
      })
      .filter(Boolean);
  } catch (e) {
    console.warn("[bama] desk headlines unavailable:", String((e && e.message) || e).slice(0, 140));
    return [];
  }
}

// Masthead line: how much of the wire the desk has scoured lately.
export async function editionStats() {
  try {
    const { stories } = await getCollections();
    const [total, last24] = await Promise.all([
      stories.countDocuments({ discoveredAt: { $gte: new Date(Date.now() - 14 * 86400e3) } }),
      stories.countDocuments({ discoveredAt: { $gte: new Date(Date.now() - 24 * 3600e3) } }),
    ]);
    const board = await (await getCollections()).board.countDocuments({});
    return { stories: total, today: last24, boardPosts: board };
  } catch {
    return { stories: 0, today: 0, boardPosts: 0 };
  }
}