import { ContactCard } from '../interfaces/whatsapp-engine.interface';

/**
 * Build a VERSION:3.0 vCard for a contact-card send, shared by both engine adapters.
 *
 * CR/LF are stripped from the name and number so a crafted value (e.g. `name = "Alice\r\nEMAIL:..."`)
 * cannot inject extra vCard lines/fields, and the `waid` is reduced to digits. The number is used once
 * in the TEL value as-is (after the CR/LF strip) rather than being unconditionally `+`-prefixed.
 */
export function buildVCard(contact: ContactCard): string {
  const clean = (s: string): string => s.replace(/[\r\n]+/g, ' ');
  // Escape the vCard structural characters in a text value (RFC 6350 §3.4). Backslash MUST be escaped
  // first so the backslashes we add for ; and , are not themselves doubled. NOTE: the source literals
  // are double-backslashed on purpose — `'\\;'` is a literal backslash+semicolon, whereas `'\;'` would
  // be a JS no-op (the unknown escape collapses to just `;`).
  const esc = (s: string): string => s.replace(/\\/g, '\\\\').replace(/;/g, '\\;').replace(/,/g, '\\,');
  const name = clean(contact.name);
  const number = clean(contact.number);
  const waid = number.replace(/\D/g, '');
  return [
    'BEGIN:VCARD',
    'VERSION:3.0',
    `FN:${esc(name)}`,
    `TEL;type=CELL;type=VOICE;waid=${waid}:${number}`,
    'END:VCARD',
  ].join('\n');
}