fix: smtp timeout

src/Effect.Email.js

@@ -1,4 +1,35 @@
-import { checkEmail } from 'qed-mail'
+import { checkSyntax, checkMX, checkSMTP } from 'qed-mail'
+
+const DEFAULT_RESULT = {
+  reachable: false,
+
+  syntax: { valid: false },
+  mx: { valid: false },
+  smtp: { valid: false },
+};
+
+/** @type {(_: string) => Promise<import('qed-mail/src/types.js').Result>} */
+async function checkEmail(email) {
+  const result = { email, ...DEFAULT_RESULT };
+
+  const syntax = checkSyntax(email);
+  if (!syntax.valid) {
+    return { ...result, syntax };
+  }
+
+  const mx = await checkMX(syntax.domain || '');
+  if (!mx.valid || !mx.mxRecords) {
+    return { ...result, syntax, mx };
+  }
+
+  const records = mx.mxRecords.sort((a, b) => a.priority - b.priority);
+  const smtp = await checkSMTP(email, records[0].exchange, 500);
+  if (!smtp.valid) {
+    return { ...result, syntax, mx, smtp };
+  }
+
+  return { ...result, reachable: true, syntax, mx, smtp };
+}
 
 /** @type {(_: string) => () => Promise<import('qed-mail/src/types.js').Result>} */
 export const checkEmailImpl = s => () => checkEmail(s)