fix(whatsapp): prevent merged lid conversations from returning

server/src/index.js

@@ -33,6 +33,7 @@ import { isTimestampOlderThan, webhookEventClaimDecision } from './reliability.j
 import {
   canonicalWhatsAppJid,
   isWeakWhatsAppDisplayName,
+  resolvedWhatsAppJid,
   reusableWhatsAppConversations,
   whatsappConversationActivityAt,
   whatsappCustomerStableId,
@@ -3231,7 +3232,9 @@ async function upsertWhatsAppMessage(tenantId, channel, rawMessage, options = {}
   if (!rawJid || !rawMessage.id) return null
   const aliasCacheKey = `${channel.gatewayAccountId}:${rawJid}`
   const cachedJid = whatsappCanonicalJidCache.get(aliasCacheKey)
-  const preliminaryJid = cachedJid || rawJid
+  const rawCanonicalJid = canonicalWhatsAppJid(rawJid)
+  const hasCanonicalAlias = Boolean(cachedJid && cachedJid !== rawCanonicalJid)
+  const preliminaryJid = hasCanonicalAlias ? cachedJid : rawCanonicalJid
   const rawConversationId = `${channel.id}:${rawJid}`
   const preliminaryConversationId = `${channel.id}:${preliminaryJid}`
   const preliminaryCustomer = await resolveWhatsAppCustomer(
@@ -3242,7 +3245,7 @@ async function upsertWhatsAppMessage(tenantId, channel, rawMessage, options = {}
   )
   const needsIdentity = Boolean(
     options.identity
-    || (rawJid.endsWith('@lid') && !cachedJid)
+    || (rawJid.endsWith('@lid') && !hasCanonicalAlias)
     || !preliminaryCustomer
     || isWeakWhatsAppDisplayName(preliminaryCustomer?.name, rawJid),
   )
@@ -3256,8 +3259,15 @@ async function upsertWhatsAppMessage(tenantId, channel, rawMessage, options = {}
         avatarUrl: preliminaryCustomer.avatarUrl,
         chatType: preliminaryCustomer.whatsappChatType,
       })
-  const jid = cachedJid || canonicalWhatsAppJid(rawJid, identity || {})
-  whatsappCanonicalJidCache.set(aliasCacheKey, jid)
+  const jid = resolvedWhatsAppJid(rawJid, identity || {}, cachedJid)
+  // A LID is a temporary alias, not a stable customer identity. Never cache an
+  // unresolved LID as canonical; otherwise a later sync can recreate a merged
+  // duplicate conversation even after the gateway learns its phone JID.
+  if (jid !== rawCanonicalJid || !rawJid.endsWith('@lid')) {
+    whatsappCanonicalJidCache.set(aliasCacheKey, jid)
+  } else {
+    whatsappCanonicalJidCache.delete(aliasCacheKey)
+  }
   const conversationId = `${channel.id}:${jid}`
   if (
     await getResource(tenantId, 'conversation-tombstones', conversationId)
@@ -3478,6 +3488,11 @@ async function mergeLegacyWhatsAppConversations(tenantId, channel, jid, aliasJid
       await deleteResource(tenantId, `messages:${source.id}`, message.id)
     }
     await deleteResource(tenantId, 'conversations', source.id)
+    broadcast(tenantId, {
+      type: 'conversation.deleted',
+      conversationId: source.id,
+      mergedIntoConversationId: targetId,
+    })
   }
   await patchResource(tenantId, 'conversations', targetId, {
     customerId,

server/src/whatsapp-identity.js

@@ -13,6 +13,15 @@ export function canonicalWhatsAppJid(jid, identity = {}) {
   return phone ? `${phone}@s.whatsapp.net` : raw
 }
 
+export function resolvedWhatsAppJid(jid, identity = {}, cachedJid = '') {
+  const fallback = canonicalWhatsAppJid(jid)
+  const resolved = canonicalWhatsAppJid(jid, identity)
+  if (resolved && resolved !== fallback) return resolved
+
+  const cached = canonicalWhatsAppJid(cachedJid)
+  return cached && cached !== fallback ? cached : fallback
+}
+
 export function whatsappCustomerStableId(jid) {
   const normalized = canonicalWhatsAppJid(jid)
   const hash = crypto.createHash('sha256').update(normalized).digest('hex').slice(0, 24)