'use strict';

const mongoose = require('mongoose');
const debug = require('debug')('agm:migrateAddresses');
const { DBConnection } = require('../helpers/db/connect.js'); // Database connection function
const models = require('../model/index.js'); // Load models
const utils = require('../helpers/utils.js');

// Parse command line arguments
const args = process.argv.slice(2);
const isDryRun = args.includes('--dry-run');

if (isDryRun) {
  debug('Running in DRY-RUN mode - no changes will be made');
}

// Initialize database connection
const workerDB = new DBConnection('Address Migration Worker');

async function migrateAddresses() {
  debug('Starting address migration...');

  // Fetch customers with the old `billAddress` field and empty addresses array
  const customers = await models.Customer.find({ 
    billAddress: { $exists: true },
    $or: [
      { addresses: { $exists: false } },
      { addresses: { $size: 0 } }
    ]
  }).lean();

  if (utils.isEmptyArray(customers)) {
    debug('No customers found with the old `billAddress` field and empty addresses array.');
    return;
  }

  debug(`Found ${customers.length} customers to migrate.`);

  for (const customer of customers) {
    try {
      if (customer.billAddress) {
        // Convert the single-line `billAddress` to the new `addresses` array format
        const newAddress = {
          ...customer.billAddress, // Assuming `billAddress` has fields matching the new AddressSchema
          isBilling: true // Mark as the current billing address
        };

        if (isDryRun) {
          debug(`[DRY-RUN] Would migrate customer ID: ${customer._id}, username: ${customer.username}`);
          debug(`[DRY-RUN] New address would be:`, JSON.stringify(newAddress, null, 2));
        } else {
          // Update the customer document
          await models.Customer.updateOne(
            { _id: customer._id },
            {
              $set: { addresses: [newAddress] }, // Add the new `addresses` array
              $unset: { billAddress: '' } // Remove the old `billAddress` field
            }
          );
          debug(`Migrated addresses for customer ID: ${customer._id}, username: ${customer.username}`);
        }
      }
    } catch (error) {
      debug(`Error migrating addresses for customer ID:  ${customer._id}, username: ${customer.username}`, error);
    }
  }

  if (isDryRun) {
    debug('Address migration DRY-RUN completed. No changes were made.');
  } else {
    debug('Address migration completed.');
  }
}

// Initialize the database connection and start migration
workerDB.initialize({
  setupExitHandlers: false,
  onReady: async () => {
    try {
      await migrateAddresses();
      process.exit(0);
    } catch (error) {
      debug('Migration failed:', error);
      process.exit(1);
    }
  }
});