#!/usr/bin/env node
/**
 * Cross-checks the intake form's two field tables. `npm run check:intake`.
 *
 * WHY THERE ARE TWO TABLES AT ALL, because the obvious reaction to this script
 * is to delete one of them and share an import. `docs/05-backend-spec.md`:
 * *"Client-side validation is a convenience. **The Lambda re-validates
 * everything.**"* A server that validates against a list the client shipped it
 * is not validating — it is asking the caller what the rules are. And the Lambda
 * is a separately deployed zip that cannot import from `src/` anyway.
 *
 * So the duplication is architectural, and what makes it safe is this check
 * rather than a shared module: the two tables must agree on every field NAME, on
 * which fields are REQUIRED, on every length CAP, and on every closed OPTION
 * SET. If they disagree, the form offers something the handler rejects, or the
 * handler accepts something the form never shows — and the first is a lost
 * inquiry that looks like a bug in the browser.
 *
 * This is the one place in the repo where a duplicated fact is deliberate, and
 * `AGENTS.md`'s standing rule about duplicated facts is why it needs a mechanism
 * on top of a comment.
 *
 * Both files are read directly — Node strips the types out of the `.ts` — so
 * this script holds no third copy of the list.
 */
import { INTAKE_FIELDS, HONEYPOT_FIELD } from '../src/data/intake.ts';
import {
  FIELDS as SERVER_FIELDS,
  HONEYPOT,
} from '../backend/intake/fields.mjs';

/**
 * BOTH TABLES ARE IMPORTED, NOT PARSED. The first version of this script read
 * `handler.mjs` as text, sliced out the `const FIELDS = [ … ]` literal, munged
 * quotes and commas into JSON, and guarded the result with a regex meant to
 * refuse anything executable.
 *
 * **That guard rejected the table on the word `process`, which is a FIELD NAME.**
 * A guard that fires on the data it exists to protect is worse than no guard,
 * and the munging underneath it would have broken on the first apostrophe or
 * URL in a label. The fix was not a better regex: the server's table moved into
 * `backend/intake/fields.mjs`, which has no module-scope side effects and can
 * simply be imported. The independence that matters is that the SERVER's table
 * lives with the server and the handler trusts nothing from `src/` — not that a
 * check script refuses to load it.
 */

const problems = [];
const server = SERVER_FIELDS;

const clientNames = INTAKE_FIELDS.map((f) => f.name);
const serverNames = server.map((f) => f.name);

for (const name of clientNames) {
  if (!serverNames.includes(name)) {
    problems.push(
      `"${name}" is on the form but the handler does not accept it — the ` +
        'inquirer would fill it and it would be silently dropped.',
    );
  }
}
for (const name of serverNames) {
  if (!clientNames.includes(name)) {
    problems.push(
      `"${name}" is validated by the handler but is not on the form.`,
    );
  }
}
if (HONEYPOT !== HONEYPOT_FIELD) {
  problems.push(
    `honeypot name differs: form "${HONEYPOT_FIELD}", handler "${HONEYPOT}". ` +
      'A bot fills the field the form renders; the handler checks the one it ' +
      'knows about, so a mismatch disables the honeypot silently.',
  );
}
if (serverNames.includes(HONEYPOT_FIELD)) {
  problems.push(
    `the honeypot "${HONEYPOT_FIELD}" is in the handler's FIELDS table; it must ` +
      'be checked separately, or a bot filling it would just fail validation ' +
      'instead of being sent to the success page.',
  );
}

for (const clientField of INTAKE_FIELDS) {
  const serverField = server.find((f) => f.name === clientField.name);
  if (!serverField) continue;

  if (Boolean(clientField.required) !== Boolean(serverField.required)) {
    problems.push(
      `"${clientField.name}": form required=${Boolean(clientField.required)}, ` +
        `handler required=${Boolean(serverField.required)}. A field the form ` +
        'marks optional and the handler requires is a rejection the inquirer ' +
        'cannot see the reason for.',
    );
  }

  /* LABELS TOO, since 2026-08-31. The handler now renders `f.label` into the
     confirmation email the inquirer keeps, so a label that drifts from the
     form's own wording means the receipt describes fields by names the form
     never showed. One more comparison; the duplication stays mechanical. */
  if (clientField.label !== serverField.label) {
    problems.push(
      `"${clientField.name}": labels differ.\n` +
        `        form:    ${JSON.stringify(clientField.label)}\n` +
        `        handler: ${JSON.stringify(serverField.label ?? null)}\n` +
        '        The handler renders its label into the confirmation email.',
    );
  }

  if ((clientField.max ?? null) !== (serverField.max ?? null)) {
    problems.push(
      `"${clientField.name}": form max=${clientField.max ?? 'none'}, ` +
        `handler max=${serverField.max ?? 'none'}. The form's maxlength stops ` +
        'typing; a lower cap in the handler rejects a submission that looked fine.',
    );
  }

  const clientOptions = clientField.options ? [...clientField.options] : null;
  const serverOptions = serverField.options ? [...serverField.options] : null;
  if (JSON.stringify(clientOptions) !== JSON.stringify(serverOptions)) {
    problems.push(
      `"${clientField.name}": option sets differ.\n` +
        `        form:    ${JSON.stringify(clientOptions)}\n` +
        `        handler: ${JSON.stringify(serverOptions)}`,
    );
  }
}

console.log(
  `check:intake — ${clientNames.length} form fields, ${serverNames.length} ` +
    'handler fields, compared on name, label, requiredness, cap and option set.',
);
if (problems.length > 0) {
  console.error(`\nINTAKE TABLE MISMATCH — ${problems.length}:`);
  for (const p of problems) console.error(`  - ${p}`);
  console.error(
    '\ndocs/05: the handler re-validates everything. The two tables are ' +
      'independent on purpose; they still have to agree.',
  );
  process.exit(1);
}
console.log('OK — the form and the handler agree.');