/**
 * One-off data migration: fix group-stage match times stored as local-wall-time-as-UTC.
 *
 * Before the schedule-form fix, the admin's local wall-clock time (PDT, UTC-7) was
 * stored as if it were UTC, so every `group_stage_matches.scheduled_at` is 7 hours
 * behind the true UTC instant. This shifts them +7 hours.
 *
 * Scope: ONLY `group_stage_matches.scheduled_at` (where not null). Playoff games
 * (`playoff_match_games.scheduled_at`) were saved correctly and are left untouched.
 *
 * NOT idempotent — running with --apply twice double-shifts. Defaults to a dry-run;
 * pass --apply to write.
 *
 * Usage (loads .env via dotenv-cli):
 *   npx dotenv -- node scripts/fix-group-match-times-utc.mjs            # preview
 *   npx dotenv -- node scripts/fix-group-match-times-utc.mjs --apply    # apply
 */

import postgres from "postgres";

const SHIFT = "7 hours"; // PDT (UTC-7) wall-clock stored as UTC -> true UTC
const apply = process.argv.includes("--apply");

const DATABASE_URL = process.env.DATABASE_DIRECT_URL || process.env.DATABASE_URL;
if (!DATABASE_URL) {
  console.error("ERROR: DATABASE_DIRECT_URL (or DATABASE_URL) is required");
  process.exit(1);
}

const sql = postgres(DATABASE_URL, { max: 1, onnotice: () => {} });

try {
  const [{ count }] = await sql`
    SELECT COUNT(*)::int AS count
    FROM group_stage_matches
    WHERE scheduled_at IS NOT NULL
  `;
  console.log(`Group-stage matches with a scheduled time: ${count}`);

  if (count === 0) {
    console.log("Nothing to do.");
    await sql.end();
    process.exit(0);
  }

  const samples = await sql`
    SELECT id,
           scheduled_at AS before,
           scheduled_at + ${sql.unsafe(`interval '${SHIFT}'`)} AS after
    FROM group_stage_matches
    WHERE scheduled_at IS NOT NULL
    ORDER BY scheduled_at
    LIMIT 10
  `;
  console.log(`\nSample before -> after (+${SHIFT}):`);
  for (const r of samples) {
    console.log(`  ${r.id}: ${r.before.toISOString()} -> ${r.after.toISOString()}`);
  }

  if (!apply) {
    console.log(`\nDRY RUN — no changes written. Re-run with --apply to shift ${count} row(s) +${SHIFT}.`);
    await sql.end();
    process.exit(0);
  }

  const result = await sql`
    UPDATE group_stage_matches
    SET scheduled_at = scheduled_at + ${sql.unsafe(`interval '${SHIFT}'`)}
    WHERE scheduled_at IS NOT NULL
  `;
  console.log(`\nApplied: shifted ${result.count} row(s) +${SHIFT}.`);
  await sql.end();
  process.exit(0);
} catch (err) {
  console.error("Migration failed:", err);
  await sql.end().catch(() => {});
  process.exit(1);
}