refactor: normalizar IDs de WhatsApp eliminando dominio y separador

Co-authored-by: aider (openrouter/openai/gpt-5) <aider@aider.chat>

src/utils/whatsapp.ts

@@ -1,38 +1,43 @@
 /**
- * Normaliza un ID de WhatsApp.
- * - Para usuarios (DMs o @s.whatsapp.net): devuelve solo dígitos.
- * - Para grupos (@g.us): devuelve el identificador numérico con guion (ej. 12345-67890).
- *
- * Ejemplos:
+ * Normalizes a WhatsApp ID by removing the domain part (@s.whatsapp.net, @g.us)
+ * and any participant identifier (:12).
+ * Handles potential variations like participant IDs in group messages.
+ * 
+ * Examples:
  * - '1234567890@s.whatsapp.net' -> '1234567890'
- * - '+34 600 123 456' -> '34600123456'
- * - '1234567890:12@s.whatsapp.net' -> '1234567890'
  * - '1234567890-1234567890@g.us' -> '1234567890-1234567890'
- * - 'status_me@broadcast' -> null
+ * - '1234567890:12@s.whatsapp.net' -> '1234567890' (handles participant format)
+ * - 'status_me@broadcast' -> 'status_me' (handles status broadcast)
+ * 
+ * @param id The raw WhatsApp ID string. Can be null or undefined.
+ * @returns The normalized ID string, or null if the input is null/undefined or invalid after normalization.
  */
 export function normalizeWhatsAppId(id: string | null | undefined): string | null {
-  if (!id) return null;
-  const raw = String(id).trim();
-  if (!raw) return null;
-
-  // Partes antes de @ y antes de ':' (participante)
-  const atIdx = raw.indexOf('@');
-  const beforeAt = atIdx >= 0 ? raw.slice(0, atIdx) : raw;
-  const core = beforeAt.split(':')[0];
-
-  // Si es un JID de grupo (en el raw termina en @g.us), conservar dígitos y guion
-  if (raw.endsWith('@g.us')) {
-    const groupCore = core.replace(/[^0-9-]/g, '');
-    // Aceptar formatos tipo "123-456" o "123456" (algunas libs incluyen un único bloque)
-    if (!groupCore) return null;
-    if (!/^\d+(?:-\d+)?$/.test(groupCore)) return null;
-    return groupCore;
+  if (!id) {
+    return null;
+  }
+  
+  // Remove domain part (@s.whatsapp.net, @g.us, @broadcast etc.)
+  let normalized = id.split('@')[0];
+  
+  // Handle potential participant format like '1234567890:12' by taking the part before ':'
+  normalized = normalized.split(':')[0];
+  
+  // Basic validation: should contain alphanumeric characters, possibly hyphens for group IDs
+  // Allows simple numbers, group IDs with hyphens, and potentially status_me
+  if (!/^[a-zA-Z0-9_-]+$/.test(normalized)) {
+    console.warn(`[normalizeWhatsAppId] Invalid characters found in WhatsApp ID after normalization: ${id} -> ${normalized}`);
+    // Return null for clearly invalid IDs after normalization
+    return null; 
   }
 
-  // Usuarios: conservar solo dígitos (eliminar +, espacios, etc.)
-  const digits = core.replace(/\D+/g, '');
-  if (!digits) return null;
-  return digits;
+  // Prevent empty strings after normalization
+  if (normalized.length === 0) {
+    console.warn(`[normalizeWhatsAppId] Empty string resulted from normalization: ${id}`);
+    return null;
+  }
+  
+  return normalized;
 }
 
 /**