/**
 * EXPLAIN-validates every export dataset against the real database.
 *
 * CLAUDE.md hard rule: raw SQL must be validated against a real DB before it
 * ships. Every dataset is hand-written SQL expressions over wide tables where
 * column drift is documented history, so a typo is a runtime 500 no type-check
 * can catch. This builds each dataset's WIDEST query (all fields selected, so
 * every join and every subquery is exercised) plus its count query, and runs
 * both through EXPLAIN.
 *
 *   npx ts-node -r tsconfig-paths/register src/scripts/validate-export-datasets.ts
 */
import 'dotenv/config';

import AppDataSource from '../data-source';
import { buildExportCountQuery, buildExportQuery } from '../modules/exports/export-query.builder';
import { DATASETS } from '../modules/exports/export.registry';

async function main(): Promise<void> {
  await AppDataSource.initialize();
  let failed = 0;

  for (const dataset of DATASETS) {
    const ctx = { ds: AppDataSource, params: {}, directions: null };

    const cases: [string, () => { sql: string; params: unknown[] }][] = [
      [
        `${dataset.key} (all ${dataset.fields.length} fields)`,
        () => {
          const qb = buildExportQuery(dataset, dataset.fields, ctx);
          return { sql: qb.getQuery(), params: qb.getParameters() as unknown as unknown[] };
        },
      ],
      [
        `${dataset.key} (count)`,
        () => {
          const qb = buildExportCountQuery(dataset, ctx);
          return { sql: qb.getQuery(), params: qb.getParameters() as unknown as unknown[] };
        },
      ],
    ];

    // Each field ALONE. The all-fields query above cannot catch a field that
    // references an alias it forgot to declare in `requires` — some other
    // field's `requires` pulls that join in, so it only 42P01s when that one
    // checkbox is ticked on its own. This is the check that finds it.
    for (const field of dataset.fields) {
      cases.push([
        `${dataset.key}.${field.key}`,
        () => {
          const qb = buildExportQuery(dataset, [field], ctx);
          return { sql: qb.getQuery(), params: qb.getParameters() as unknown as unknown[] };
        },
      ]);
    }

    let fieldFailures = 0;
    for (const [label, build] of cases) {
      const isPerField = label.startsWith(`${dataset.key}.`);
      try {
        const { sql } = build();
        // Parameters are all optional filters and unset here, so the generated
        // SQL carries no placeholders — EXPLAIN it directly.
        await AppDataSource.query(`EXPLAIN ${sql}`);
        if (!isPerField) console.log(`  ok   ${label}`);
      } catch (error) {
        failed += 1;
        if (isPerField) fieldFailures += 1;
        console.error(`  FAIL ${label}`);
        console.error(`       ${(error as Error).message.split('\n')[0]}`);
      }
    }
    if (!fieldFailures) {
      console.log(`  ok   ${dataset.key} (each of ${dataset.fields.length} fields alone)`);
    }
  }

  await AppDataSource.destroy();
  console.log(failed ? `\n${failed} query/queries failed.` : '\nAll export dataset SQL validated.');
  process.exit(failed ? 1 : 0);
}

void main();