import { getDbPool } from '../../server/src/db/pool.js';
import { createScriptLogger } from './postal-logging.js';

async function logPostalAreaCounts() {
  const pool = getDbPool();
  const result = await pool.query<{ country_code: string; area_count: string }>(`
    select country_code, count(*)::text as area_count
    from public.postal_areas
    group by country_code
    order by country_code asc
  `);

  return result.rows;
}

async function buildNeighborsForCountry(countryCode: 'US' | 'CA') {
  const pool = getDbPool();
  const logger = createScriptLogger(`postal-neighbors:${countryCode.toLowerCase()}`);

  const sourceCountResult = await pool.query<{ area_count: string }>(
    `select count(*)::text as area_count from public.postal_areas where country_code = $1`,
    [countryCode],
  );

  const areaCount = sourceCountResult.rows[0]?.area_count ?? '0';
  logger.info(`Starting neighbor build for ${countryCode} with ${areaCount} postal areas.`);

  await pool.query(
    `
      insert into public.postal_area_neighbors (postal_area_id, neighbor_postal_area_id)
      select source.id, neighbor.id
      from public.postal_areas source
      join public.postal_areas neighbor
        on source.country_code = neighbor.country_code
       and source.id <> neighbor.id
       and ST_Touches(source.geom, neighbor.geom)
      where source.country_code = $1
    `,
    [countryCode],
  );

  const neighborCountResult = await pool.query<{ neighbor_count: string }>(
    `
      select count(*)::text as neighbor_count
      from public.postal_area_neighbors link
      join public.postal_areas area on area.id = link.postal_area_id
      where area.country_code = $1
    `,
    [countryCode],
  );

  logger.info(`Completed neighbor build for ${countryCode}. Built ${neighborCountResult.rows[0]?.neighbor_count ?? '0'} adjacency links.`);
}

async function run() {
  const logger = createScriptLogger('postal-neighbors');
  const pool = getDbPool();
  const client = await pool.connect();

  try {
    logger.info('Gathering postal area counts before neighbor build.');
    const counts = await logPostalAreaCounts();
    counts.forEach((row) => logger.info(`Found ${row.area_count} postal areas for ${row.country_code}.`));

    await client.query('begin');
    logger.info('Clearing existing postal adjacency links.');
    await client.query('truncate table public.postal_area_neighbors');
    await client.query('commit');

    await buildNeighborsForCountry('US');
    await buildNeighborsForCountry('CA');

    const summary = await pool.query<{ count: string }>('select count(*)::text as count from public.postal_area_neighbors');
    logger.info(`Finished building postal neighbors. Total adjacency links: ${summary.rows[0]?.count ?? '0'}.`);
  } catch (error) {
    await client.query('rollback');
    logger.error('Neighbor build failed.');
    throw error;
  } finally {
    client.release();
    await pool.end();
  }
}

await run();