fix(ui): enforce save semantics for default and preset chunks

src/controllers/preset.py

@@ -171,9 +171,13 @@ async def send_presets(request, session):
     if not sender:
         return json.dumps({"error": "Transport not configured"}), 503, {'Content-Type': 'application/json'}
 
-    async def send_chunk(chunk_presets):
-        # Include save flag so the led-driver can persist when desired.
-        msg = build_message(presets=chunk_presets, save=save_flag, default=default_id)
+    async def send_chunk(chunk_presets, is_last):
+        # Save/default should only be sent with the final presets chunk.
+        msg = build_message(
+            presets=chunk_presets,
+            save=save_flag and is_last,
+            default=default_id if is_last else None,
+        )
         await sender.send(msg, addr=destination_mac)
 
     MAX_BYTES = 240
@@ -195,7 +199,7 @@ async def send_presets(request, session):
             last_msg = test_msg
         else:
             try:
-                await send_chunk(batch)
+                await send_chunk(batch, False)
             except Exception:
                 return json.dumps({"error": "Send failed"}), 503, {'Content-Type': 'application/json'}
             await asyncio.sleep(send_delay_s)
@@ -205,7 +209,7 @@ async def send_presets(request, session):
 
     if batch:
         try:
-            await send_chunk(batch)
+            await send_chunk(batch, True)
         except Exception:
             return json.dumps({"error": "Send failed"}), 503, {'Content-Type': 'application/json'}
         await asyncio.sleep(send_delay_s)

src/static/presets.js

@@ -132,7 +132,7 @@ const sendEspnowMessage = (obj) => {
 
 // Send a select message for a preset to all device names in the current tab.
 // Uses the preset ID as the select key.
-const sendSelectForCurrentTabDevices = (presetId, sectionEl, saveToDevice = true) => {
+const sendSelectForCurrentTabDevices = (presetId, sectionEl) => {
   const section = sectionEl || document.querySelector('.presets-section[data-tab-id]');
   if (!section || !presetId) {
     return;
@@ -155,9 +155,6 @@ const sendSelectForCurrentTabDevices = (presetId, sectionEl, saveToDevice = true
     v: '1',
     select,
   };
-  if (saveToDevice) {
-    message.save = true;
-  }
 
   sendEspnowMessage(message);
 };
@@ -1325,9 +1322,8 @@ document.addEventListener('DOMContentLoaded', () => {
 
 // Build ESPNow messages for a single preset.
 // Send order:
-// 1) preset payload (without save)
-// 2) optional select for device names
-// 3) optional save command
+// 1) preset payload (optionally with save)
+// 2) optional select for device names (never with save)
 // saveToDevice defaults to true.
 const sendPresetViaEspNow = async (presetId, preset, deviceNames, saveToDevice = true, setDefault = false) => {
   try {
@@ -1394,11 +1390,13 @@ const sendDefaultPreset = (presetId, deviceNames) => {
     return;
   }
   // Default should only set startup preset, not trigger live selection.
+  // Save is attached to default messages.
   // When device names are provided, scope the default update to those devices.
   const targets = Array.isArray(deviceNames)
     ? deviceNames.map((n) => (n || '').trim()).filter((n) => n.length > 0)
     : [];
   const message = { v: '1', default: presetId };
+  message.save = true;
   if (targets.length > 0) {
     message.targets = targets;
   }

src/static/tabs.js

@@ -354,7 +354,7 @@ async function loadTabContent(tabId) {
                 brightnessSendTimeout = setTimeout(() => {
                     if (typeof window.sendEspnowRaw === 'function') {
                         try {
-                            window.sendEspnowRaw({ v: '1', b: val });
+                            window.sendEspnowRaw({ v: '1', b: val, save: true });
                         } catch (err) {
                             console.error('Failed to send brightness via ESPNow:', err);
                         }