/**
 * tests/js/test_field_heuristics.js — run with:
 *   node tests/js/test_field_heuristics.js
 *
 * Pins the field-detection predicates in extension/content/content.js against
 * the ASUS RT-AX88U router login page, which the extension could not detect.
 *
 * The username input there is about as obvious as they come:
 *
 *   <input type="text" id="login_username" name="login_username"
 *          class="form_input" placeholder="Username" autocomplete="off">
 *
 * but "off" was in the NON_CRED_AC deny-list, so _isLikelyUsernameField()
 * returned false at that check and never reached the name/id/placeholder
 * keyword test. `autocomplete="off"` says nothing about whether a field holds a
 * credential — routers and admin panels set it specifically to discourage
 * password managers.
 *
 * SCOPE: this exercises the regex predicates extracted from the real source
 * file, not the DOM traversal in _hasPasswordSibling() (which needs a browser).
 * Those paths are covered by the manual check in the accompanying notes.
 */
'use strict';

const fs = require('fs');
const path = require('path');

const SRC = fs.readFileSync(
  path.join(__dirname, '..', '..', 'extension', 'content', 'content.js'),
  'utf8',
);

let failures = 0;

function check(label, got, want) {
  if (got !== want) {
    failures++;
    console.log(`FAIL  ${label}\n      got=${got} want=${want}`);
  }
}

/** Pull a named regex literal out of the real source rather than copying it. */
function extractRegex(name) {
  const m = SRC.match(new RegExp(`const ${name} =\\s*(/[^\\n]+/[a-z]*);`));
  if (!m) throw new Error(`could not find regex ${name} in content.js`);
  // eslint-disable-next-line no-eval
  return eval(m[1]);
}

const CRED_HINTS = extractRegex('CRED_HINTS');
const NON_CRED_AC = extractRegex('NON_CRED_AC');

// ── The bug: autocomplete="off" must not be a negative signal ───────────────
check('NON_CRED_AC rejects "off"', NON_CRED_AC.test('off'), false);
check('NON_CRED_AC rejects "OFF" (case-insensitive)', NON_CRED_AC.test('OFF'), false);

// Anti-autofill junk values sites use must also fall through to the keywords.
for (const junk of ['nope', 'no', 'false', 'disabled', 'new-user', 'chrome-off']) {
  check(`NON_CRED_AC lets junk value "${junk}" fall through`,
        NON_CRED_AC.test(junk), false);
}

// ── But genuine non-credential tokens must still be rejected ───────────────
for (const token of ['name', 'given-name', 'family-name', 'organization',
                     'street-address', 'country', 'postal-code', 'search',
                     'url', 'bday', 'sex', 'photo', 'language',
                     'new-password', 'current-password', 'one-time-code']) {
  check(`NON_CRED_AC still rejects "${token}"`, NON_CRED_AC.test(token), true);
}

// ── The ASUS field's identifying attributes must read as a credential ───────
const ASUS_USERNAME_ATTRS = ['login_username', 'login_username', 'Username', ''].join(' ');
check('ASUS username attrs match CRED_HINTS',
      CRED_HINTS.test(ASUS_USERNAME_ATTRS), true);

// Other real-world username fields.
for (const attrs of ['user_name', 'j_username', 'email', 'userEmail',
                     'account', 'Login ID', 'mobile', 'tel']) {
  check(`CRED_HINTS matches "${attrs}"`, CRED_HINTS.test(attrs), true);
}

// Fields that must NOT be treated as credential inputs on keywords alone.
for (const attrs of ['q', 'search-query', 'first_name', 'zipcode',
                     'street', 'company', 'comment']) {
  check(`CRED_HINTS does not match "${attrs}"`, CRED_HINTS.test(attrs), false);
}

// ── Submit-control detection for pages with no <form> ──────────────────────
// The ASUS page submits via <div class="button" onclick="preLogin();">, so no
// "submit" event ever fires and the save prompt never appeared.
const clsMatch = SRC.match(
  /return (\/\(\^\|\[\\s_-\]\)\(btn\|button[^\n]+\/)\.test\(cls\);/,
);
if (!clsMatch) {
  failures++;
  console.log('FAIL  could not find the submit-control class regex in content.js');
} else {
  // eslint-disable-next-line no-eval
  const BTN_CLS = eval(clsMatch[1]);
  check('recognises class="button" (ASUS)', BTN_CLS.test('button'), true);
  for (const cls of ['btn', 'btn btn-primary', 'submit', 'login-button',
                     'signin', 'sign-in', 'form_btn button']) {
    check(`recognises class="${cls}"`, BTN_CLS.test(cls), true);
  }
  for (const cls of ['form_input', 'container', 'buttonish', 'rebutton']) {
    check(`ignores class="${cls}"`, BTN_CLS.test(cls), false);
  }
}

// The click and keydown fallbacks must actually be registered.
check('click fallback registered', /addEventListener\(\s*"click"/.test(SRC), true);
check('keydown fallback registered', /addEventListener\(\s*"keydown"/.test(SRC), true);
check('submit listener retained', /addEventListener\(\s*"submit"/.test(SRC), true);

// ── _isTrustworthyOrigin: where credentials may be filled ──────────────────
// Extracted from the real source and evaluated against a stubbed `location`,
// so this exercises the shipped function rather than a copy of its rules.
{
  const fnSrc = SRC.match(
    /function _isTrustworthyOrigin\(\) \{[\s\S]*?\n  \}/,
  );
  if (!fnSrc) {
    failures++;
    console.log('FAIL  could not extract _isTrustworthyOrigin from content.js');
  } else {
    const make = new Function(
      'location',
      `${fnSrc[0]}; return _isTrustworthyOrigin();`,
    );
    const at = (protocol, hostname) => make({ protocol, hostname });

    // HTTPS is always fine.
    check('https is trustworthy', at('https:', 'example.com'), true);

    // Local devices over plain HTTP — routers, NAS, printers. Dropping
    // http://*/* entirely would break exactly these.
    for (const host of ['localhost', '127.0.0.1', '::1', 'router.local',
                        '10.0.0.1', '192.168.1.1', '172.16.5.4', '172.31.0.1',
                        '169.254.1.1', 'nas.lan', 'box.home']) {
      check(`http://${host} is treated as local`, at('http:', host), true);
    }

    // Plaintext on the public internet must warn.
    for (const host of ['example.com', 'bank.co.uk', '8.8.8.8',
                        '172.15.0.1', '172.32.0.1', '11.0.0.1',
                        '192.169.1.1', 'evil-localhost.com',
                        'localhost.evil.com', '127.0.0.1.evil.com']) {
      check(`http://${host} is NOT trusted`, at('http:', host), false);
    }
  }
}

// ── Autologin must not click a control that discards the login ────────────
{
  const m = SRC.match(/var _NEGATIVE_CONTROL = (\/[^\n]+\/[a-z]*);/);
  if (!m) {
    failures++;
    console.log('FAIL  could not find _NEGATIVE_CONTROL in content.js');
  } else {
    // eslint-disable-next-line no-eval
    const NEG = eval(m[1]);
    for (const label of ['Cancel', 'Reset', 'Go back', 'Forgot password?',
                         'Register', 'Sign up', 'Create account']) {
      check(`autologin skips "${label}"`, NEG.test(label), true);
    }
    for (const label of ['Sign In', 'Log in', 'Submit', 'Continue', 'OK']) {
      check(`autologin allows "${label}"`, NEG.test(label), false);
    }
  }
}

// ── Summary (must stay last so every block above is counted) ───────────────
if (failures) {
  console.log(`\n${failures} failure(s)`);
  process.exit(1);
}
console.log('OK: field heuristics assertions passed');