import postgres from "postgres";
import { db } from "../db/manager";
import { config } from "../lib/config";
import { getSecret } from "../lib/k8s";
import { getSpacesUsage } from "./spaces";

async function collectSizes() {
  const customers = await db`SELECT slug, spaces_key FROM customers WHERE status = 'provisioned'`;
  if (customers.length === 0) return;

  for (const customer of customers) {
    const { slug } = customer;
    try {
      // DB size
      let dbSizeBytes: number | null = null;
      try {
        const sql = postgres(config.doadminDbUrl.replace(/\/([^/?]+)(\?|$)/, `/${slug}$2`), { max: 1 });
        try {
          const [row] = await sql<[{ bytes: string }]>`SELECT pg_database_size(${slug}::text)::text AS bytes`;
          dbSizeBytes = Number(row.bytes);
        } finally {
          await sql.end();
        }
      } catch {}

      // Spaces size
      let spacesSizeBytes: number | null = null;
      let spacesObjectCount: number | null = null;
      if (customer.spaces_key) {
        try {
          const namespace = `customer-${slug}`;
          const secrets = await getSecret(namespace, "lunarfront-secrets");
          const result = await getSpacesUsage(
            customer.spaces_key,
            secrets["spaces-secret"],
            config.spacesBucket,
            config.spacesRegion,
            `${slug}/`,
          );
          spacesSizeBytes = result.sizeBytes;
          spacesObjectCount = result.objectCount;
        } catch {}
      }

      // Upsert today's snapshot (one row per day per customer)
      await db`
        INSERT INTO customer_size_snapshots (slug, recorded_at, db_size_bytes, spaces_size_bytes, spaces_object_count)
        VALUES (${slug}, CURRENT_DATE, ${dbSizeBytes}, ${spacesSizeBytes}, ${spacesObjectCount})
        ON CONFLICT (slug, recorded_at) DO UPDATE SET
          db_size_bytes = EXCLUDED.db_size_bytes,
          spaces_size_bytes = EXCLUDED.spaces_size_bytes,
          spaces_object_count = EXCLUDED.spaces_object_count
      `;
    } catch (err) {
      console.error(`[sizeCollector] failed for ${slug}:`, err);
    }
  }
}

function msUntilNext12h(): number {
  const now = new Date();
  const next = new Date(now);
  const h = now.getUTCHours();
  // next run at 00:00 or 12:00 UTC, whichever is sooner
  if (h < 12) {
    next.setUTCHours(12, 0, 0, 0);
  } else {
    next.setUTCDate(next.getUTCDate() + 1);
    next.setUTCHours(0, 0, 0, 0);
  }
  return next.getTime() - now.getTime();
}

export function startSizeCollector(log: { info: (msg: string) => void }) {
  // Run immediately on startup
  collectSizes().then(() => log.info("Initial size snapshot collected")).catch(() => {});

  // Then schedule for 00:00 and 12:00 UTC
  function scheduleNext() {
    const delay = msUntilNext12h();
    setTimeout(() => {
      collectSizes().then(() => log.info("Size snapshot collected")).catch(() => {});
      scheduleNext();
    }, delay);
  }
  scheduleNext();
}