fix(whatsapp): address code review findings from Codex and manual review

P1 fixes:
- Parse Unix epoch timestamps with Time.zone.at instead of Time.zone.parse
  which silently fell back to Time.current for all GoWA webhook messages
- Halt execution in resolve_device_id when inbox validation fails, preventing
  NoMethodError on non-WhatsApp channels

P2 fixes:
- Fall back to ID-based query in messages_after when reference message is
  deleted, preserving incremental cursor semantics (upstream behavior)
- Merge duplicate 'video'/'video_note' branches in case statement
- Replace update_column with update in inbox callback to run validations

Author: milesibastos

app/controllers/api/v1/accounts/whatsapp_web/devices_controller.rb

@@ -113,18 +113,21 @@ def resolve_device_id
     @inbox = Current.account.inboxes.find_by(id: params[:id])
 
     if @inbox
-      validate_whatsapp_web_inbox
+      return validate_whatsapp_web_inbox unless valid_whatsapp_web_inbox?
+
       @device_id = @inbox.channel.provider_config['device_id']
     else
       # Pre-inbox setup: params[:id] is the device_id directly
       @device_id = params[:id]
     end
   end
 
-  def validate_whatsapp_web_inbox
+  def valid_whatsapp_web_inbox?
     channel = @inbox.channel
-    return if channel.is_a?(Channel::Whatsapp) && channel.provider == Channel::Whatsapp::WHATSAPP_WEB_PROVIDER
+    channel.is_a?(Channel::Whatsapp) && channel.provider == Channel::Whatsapp::WHATSAPP_WEB_PROVIDER
+  end
 
+  def validate_whatsapp_web_inbox
     render json: {
       success: false,
       error: 'Inbox is not a WhatsApp Web channel'

app/finders/message_finder.rb

@@ -36,7 +36,8 @@ def messages_after(after_id)
     # Find the created_at of the reference message to paginate correctly
     # This handles history-synced messages that have higher IDs but older timestamps
     reference_message = @conversation.messages.find_by(id: after_id)
-    return messages.reorder('created_at asc').limit(100) unless reference_message
+    # Fall back to ID-based query if reference message was deleted (original upstream behavior)
+    return messages.reorder('created_at asc').where('id > ?', after_id).limit(100) unless reference_message
 
     messages.reorder('created_at asc')
             .where('created_at > ? OR (created_at = ? AND id > ?)',

app/models/inbox.rb

@@ -245,7 +245,7 @@ def delete_round_robin_agents
   def enable_lock_to_single_conversation_for_whatsapp_web
     return unless channel.is_a?(Channel::Whatsapp) && channel.whatsapp_web?
 
-    update_column(:lock_to_single_conversation, true)
+    update(lock_to_single_conversation: true)
   end
 
   def check_channel_type?

app/services/whatsapp/incoming_message_whatsapp_web_service.rb

@@ -720,7 +720,12 @@ def merge_chat_info_preserving_name(enriched_chat, chat_info)
   def parse_timestamp(timestamp_str)
     return Time.current if timestamp_str.blank?
 
-    Time.zone.parse(timestamp_str)
+    # GoWA sends Unix epoch seconds (e.g. "1712345678")
+    if timestamp_str.to_s.match?(/\A\d+\z/)
+      Time.zone.at(timestamp_str.to_i)
+    else
+      Time.zone.parse(timestamp_str)
+    end
   rescue ArgumentError
     Time.current
   end
@@ -1091,11 +1096,10 @@ def add_history_media_to_payload(payload, message, chat)
 
     case media_type.downcase
     when 'image' then payload[:image] = media_obj
-    when 'video' then payload[:video] = media_obj
+    when 'video', 'video_note' then payload[:video] = media_obj
     when 'audio' then payload[:audio] = media_obj
     when 'document' then payload[:document] = media_obj
     when 'sticker' then payload[:sticker] = media_obj
-    when 'video_note' then payload[:video] = media_obj # PTV messages are video
     end
   end