#!/usr/bin/env node
/**
 * One-shot backfill for Ticket.creatorId on Discord-originated tickets.
 *
 * Modal-created tickets (`discord-${ts}-${userId}`): tail segment is the user ID — extract it.
 * Context-menu tickets (`discord-msg-${ts}-${msgId}`): tail segment is the *message* ID, not the
 * user ID. Set creatorId = null and let runtime code fall through to the default-name path.
 * Recovering these would require a Discord API fetch per message, which is unreliable for
 * already-deleted ticket channels.
 *
 * Idempotent: skips tickets that already have creatorId set.
 *
 * Usage:
 *   node scripts/backfill-creatorId.js          # dry-run, prints summary only
 *   node scripts/backfill-creatorId.js --apply  # writes
 */

require('dotenv').config();
const { connectMongoDB, closeMongoDB, mongoose } = require('../db-connection');

const APPLY = process.argv.includes('--apply');
const MODAL_RE = /^discord-\d+-(\d{17,20})$/;

async function main() {
  if (!process.env.MONGODB_URI) {
    console.error('MONGODB_URI not set');
    process.exit(1);
  }
  await connectMongoDB(process.env.MONGODB_URI);

  const Ticket = mongoose.model('Ticket');

  const candidates = await Ticket.find({
    gmailThreadId: /^discord-/,
    creatorId: { $in: [null, undefined, ''] }
  }).select('gmailThreadId creatorId').lean();

  let modalHits = 0;
  let msgSkipped = 0;
  let unknown = 0;
  const ops = [];

  for (const t of candidates) {
    const id = t.gmailThreadId;
    const modalMatch = id.match(MODAL_RE);
    if (modalMatch) {
      modalHits++;
      ops.push({
        updateOne: {
          filter: { _id: t._id },
          update: { $set: { creatorId: modalMatch[1] } }
        }
      });
      continue;
    }
    if (id.startsWith('discord-msg-')) {
      msgSkipped++;
      continue;
    }
    unknown++;
  }

  console.log(`Scanned ${candidates.length} Discord-originated tickets without creatorId.`);
  console.log(`  Modal-pattern recoverable: ${modalHits}`);
  console.log(`  Context-menu (unrecoverable, leaving null): ${msgSkipped}`);
  console.log(`  Unknown shape: ${unknown}`);

  if (!APPLY) {
    console.log('\nDry-run only. Re-run with --apply to write changes.');
    await closeMongoDB();
    return;
  }

  if (ops.length === 0) {
    console.log('Nothing to write.');
    await closeMongoDB();
    return;
  }

  const res = await Ticket.bulkWrite(ops, { ordered: false });
  console.log(`Wrote ${res.modifiedCount} updates.`);
  await closeMongoDB();
}

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