import { decryptField, encryptField, panLookup } from '../src/services/fieldCrypto.js';

/**
 * Widen bank columns and encrypt values already stored in plaintext.
 * @param {import('knex').Knex} knex
 */
export async function up(knex) {
  await knex.schema.alterTable('applications', (table) => {
    table.string('pan', 255).nullable().alter();
    table.string('account_number', 255).nullable().alter();
  });

  const hasLookup = await knex.schema.hasColumn('applications', 'pan_lookup');

  if (!hasLookup) {
    await knex.schema.alterTable('applications', (table) => {
      table.string('pan_lookup', 64).nullable().index();
    });
  }

  const rows = await knex('applications').select('id', 'pan', 'account_number', 'pan_lookup');

  for (const row of rows) {
    /** @type {Record<string, string | null>} */
    const updates = {};

    if (row.pan && !String(row.pan).startsWith('enc:v1:')) {
      updates.pan_lookup = panLookup(String(row.pan));
      updates.pan = encryptField(String(row.pan));
    }

    if (row.account_number && !String(row.account_number).startsWith('enc:v1:')) {
      updates.account_number = encryptField(String(row.account_number));
    }

    if (Object.keys(updates).length > 0) {
      await knex('applications').where({ id: row.id }).update(updates);
    }
  }
}

/**
 * @param {import('knex').Knex} knex
 */
export async function down(knex) {
  const rows = await knex('applications').select('id', 'pan', 'account_number');

  for (const row of rows) {
    /** @type {Record<string, string | null>} */
    const updates = {};

    if (row.pan && String(row.pan).startsWith('enc:v1:')) {
      updates.pan = decryptField(row.pan);
    }

    if (row.account_number && String(row.account_number).startsWith('enc:v1:')) {
      updates.account_number = decryptField(row.account_number);
    }

    if (Object.keys(updates).length > 0) {
      await knex('applications').where({ id: row.id }).update(updates);
    }
  }

  await knex.schema.alterTable('applications', (table) => {
    table.dropColumn('pan_lookup');
    table.string('pan', 10).nullable().alter();
    table.string('account_number', 18).nullable().alter();
  });
}