// Pulls usable articles from duriin into article_queue continuously
// Usable = has content, has embedding, has event assignment

async function runQueueFeeder(archiveDb, intelligenceDb, config) {
  const batchSize = config.workers?.queueFeederBatchSize ?? 100;
  const loopDelay = config.workers?.queueFeederLoopDelayMs ?? 3000;

  const getCursor = intelligenceDb.prepare(
    "SELECT value FROM cursors WHERE key = 'queue_feeder'"
  );
  const setCursor = intelligenceDb.prepare(
    "INSERT OR REPLACE INTO cursors (key, value) VALUES ('queue_feeder', ?)"
  );

  const insertQueued = intelligenceDb.prepare(`
    INSERT OR IGNORE INTO article_queue (article_id, status, created_at)
    VALUES (?, 'pending', CURRENT_TIMESTAMP)
  `);

  while (true) {
    try {
      const cursorRow = getCursor.get();
      const cursor = cursorRow ? cursorRow.value : 0;

      const articles = archiveDb.prepare(`
        SELECT id FROM articles
        WHERE id > ?
          AND content IS NOT NULL
          AND content != ''
          AND has_embedding = 1
          AND event_id IS NOT NULL
        ORDER BY id ASC
        LIMIT ?
      `).all(cursor, batchSize);

      if (articles.length === 0) {
        await sleep(loopDelay);
        continue;
      }

      let newCursor = cursor;
      let inserted = 0;

      for (const a of articles) {
        const info = insertQueued.run(a.id);
        if (info.changes > 0) inserted++;
        if (a.id > newCursor) newCursor = a.id;
      }

      setCursor.run(newCursor);

      if (inserted > 0) {
        console.log(`[feeder] queued ${inserted} articles, cursor now ${newCursor}`);
      }

    } catch (err) {
      console.error("[feeder] error:", err.message);
      await sleep(loopDelay);
    }
  }
}

function sleep(ms) {
  return new Promise(r => setTimeout(r, ms));
}

module.exports = { runQueueFeeder };