/**
 * Scrape job — fetches 2026 operating hours for all parks from the Six Flags API.
 *
 * Prerequisite: run `npm run discover` first to populate API IDs.
 *
 * Run once and leave it:
 *   npm run scrape
 *
 * Skips park+month combos scraped within the last week. Re-run to resume after interruption.
 * To force a full re-scrape:
 *   npm run scrape:force
 *
 * Rate limiting: backs off automatically (30s → 60s → 120s per retry).
 * After exhausting retries, skips that park+month and continues.
 */

import { openDb, upsertDay, getApiId, isMonthScraped } from "../lib/db";
import { PARKS } from "../lib/parks";
import { scrapeMonth, RateLimitError } from "../lib/scrapers/sixflags";

const YEAR = 2026;
const MONTHS = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12];
const DELAY_MS = 1000; // between successful API calls
const FORCE = process.argv.includes("--rescrape");

function monthLabel(m: number) {
  return `${YEAR}-${String(m).padStart(2, "0")}`;
}

function pad(n: number, width: number) {
  return String(n).padStart(width, " ");
}

async function sleep(ms: number) {
  return new Promise<void>((r) => setTimeout(r, ms));
}

async function main() {
  const db = openDb();

  // Separate parks with known API IDs from those needing discovery
  const ready = PARKS.filter((p) => getApiId(db, p.id) !== null);
  const needsDiscovery = PARKS.filter((p) => getApiId(db, p.id) === null);

  if (needsDiscovery.length > 0) {
    console.log(
      `⚠  ${needsDiscovery.length} parks have no API ID — run \`npm run discover\` first:\n` +
        needsDiscovery.map((p) => `     ${p.id}`).join("\n") +
        "\n"
    );
  }

  if (ready.length === 0) {
    console.log("No parks ready to scrape. Run: npm run discover");
    db.close();
    return;
  }

  // Build the full work queue: month × park
  const queue: { month: number; park: (typeof PARKS)[0]; apiId: number }[] = [];
  for (const month of MONTHS) {
    for (const park of ready) {
      if (!FORCE && isMonthScraped(db, park.id, YEAR, month)) continue;
      queue.push({ month, park, apiId: getApiId(db, park.id)! });
    }
  }

  const total = MONTHS.length * ready.length;
  const skip = total - queue.length;
  console.log(
    `Scraping ${YEAR} — ${ready.length} parks × 12 months = ${total} total\n` +
      `Skipping ${skip} already-scraped. ${queue.length} to fetch.\n`
  );

  if (queue.length === 0) {
    console.log("Nothing to do. To force a full re-scrape: npm run scrape:force");
    db.close();
    return;
  }

  let done = 0;
  let errors = 0;

  for (const { month, park, apiId } of queue) {
    const counter = `[${pad(done + 1, queue.length.toString().length)}/${queue.length}]`;
    process.stdout.write(`${counter} ${park.shortName.padEnd(22)} ${monthLabel(month)} ... `);

    try {
      const days = await scrapeMonth(apiId, YEAR, month);
      const insertAll = db.transaction(() => {
        for (const d of days) upsertDay(db, park.id, d.date, d.isOpen, d.hoursLabel);
      });
      insertAll();

      const openCount = days.filter((d) => d.isOpen).length;
      console.log(`${openCount}/${days.length} open`);
      done++;

      if (done < queue.length) await sleep(DELAY_MS);
    } catch (err) {
      if (err instanceof RateLimitError) {
        console.log(`RATE LIMITED — skipping (re-run to retry)`);
      } else {
        console.log(`ERROR: ${err instanceof Error ? err.message : err}`);
      }
      errors++;
    }
  }

  const summary = [
    `\n── Summary ─────────────────────────────`,
    `   Fetched : ${done}`,
    `   Skipped : ${skip}`,
    `   Errors  : ${errors}`,
    `   Total   : ${total}`,
  ];
  if (errors > 0) summary.push(`\nRe-run to retry failed months.`);
  console.log(summary.join("\n"));

  db.close();
}

main().catch((err) => {
  console.error("Fatal:", err);
  process.exit(1);
});