Keep the ambient colour when the light turns on

The MCU resets the colour to Cycle on every turn-on. Remember the chosen colour
across restarts and send it again just after the MCU reports the light on.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

CLAUDE.md

@@ -67,6 +67,7 @@ From Tuya's definition for a sibling product (tuya-local issue #3821). See the R
 - Sound 0 is silent. In Sound + Light mode, the light still came on and no sound played.
 - Alarm sounds, identified by ear: 1 birds chirping, 2 beach (water and birds), 3 galaxy twinkles, 4 piano and birds, 5 happy harp or high piano, 6 old mechanical alarm clock, 7 old digital alarm clock. Names are in `alarm_block.yaml`. Sunset's sounds 1 to 4 haven't been checked, so they keep their numbers.
 - Radio Volume and station writes are ignored with the radio off. With it on, both work, and the station stays selected after turning it off.
+- Every Ambient Light turn-on makes the MCU reset DP132 to Cycle (0), even if a colour was set while off. Since v1.0.5 the firmware remembers the chosen colour (kept across restarts) and sends it again 400 ms after the MCU reports the light on. Colour changes the MCU reports more than 1.5 s after turn-on count as user choices.
 - Keep `default_transition_length` at 0. A transition sends about 50 MCU writes a second.
 - LibreTiny before v1.14.0 can hang after a software restart or OTA until powered off for about 30 seconds (LibreTiny issue #396). The config pins v1.14.0. Drop the pin once ESPHome defaults to it or newer.
 - "Last Restart Reason" reports Power-On even after software restarts.

server-example.yaml

@@ -7,6 +7,6 @@ substitutions:
 packages:
   lamp:
     url: https://mangavalk.com/mangavalk/esphome-wake-up-light-ii.git
-    ref: v1.0.4
+    ref: v1.0.5
     files: [wake-up-light-ii.yaml]
     refresh: 1d

wake-up-light-ii.yaml

@@ -22,7 +22,7 @@ external_components:
   - source:
       type: git
       url: https://mangavalk.com/mangavalk/esphome-wake-up-light-ii.git
-      ref: v1.0.4
+      ref: v1.0.5
     components: [uart]
     refresh: 1d
 
@@ -136,6 +136,23 @@ globals:
     restore_value: no
     initial_value: '0'
 
+  # Ambient colour (DP132). The MCU resets it to Cycle (0) whenever the ambient
+  # light turns on, so the chosen colour is kept here and sent again.
+  - id: ambient_color_saved
+    type: uint8_t
+    restore_value: yes
+    initial_value: '0'
+
+  - id: ambient_color_now
+    type: uint8_t
+    restore_value: no
+    initial_value: '0'
+
+  - id: ambient_on_ms
+    type: uint32_t
+    restore_value: no
+    initial_value: '0'
+
   # When the MCU last sent its once-a-minute clock report.
   - id: last_mcu_report
     type: uint32_t
@@ -301,6 +318,24 @@ tuya:
             id(alarm_raw_valid) = true;
             id(publish_alarm_summaries).execute();
 
+    # DP129: ambient light. On every turn-on the MCU resets DP132 to Cycle.
+    - sensor_datapoint: 129
+      datapoint_type: bool
+      then:
+        - lambda: |-
+            if (!x) return;
+            id(ambient_on_ms) = millis();
+            id(restore_ambient_color).execute();
+
+    # DP132: ambient colour. A change reported while the light has been on for a
+    # moment came from the user (lamp buttons or here), so remember it.
+    - sensor_datapoint: 132
+      datapoint_type: enum
+      then:
+        - lambda: |-
+            id(ambient_color_now) = x;
+            if (millis() - id(ambient_on_ms) > 1500) id(ambient_color_saved) = x;
+
     # DP128: sunset settings, 10 bytes, per Tuya's data model:
     # [0] switch (unused) [1] mode: 0=sound, 1=sound+light, 2=radio, 3=radio+light
     # [2] sound 1..4 [3] sound volume 1..16 [4] sound duration 10..120
@@ -400,6 +435,15 @@ script:
                 call.set_transition_length(0);
                 call.perform();
 
+  - id: restore_ambient_color
+    mode: restart
+    then:
+      - delay: 400ms
+      - lambda: |-
+          if (id(ambient_color_saved) == 0) return;
+          ESP_LOGI("ambient", "Restoring ambient colour %u", (unsigned) id(ambient_color_saved));
+          id(tuya_mcu).set_enum_datapoint_value(132, id(ambient_color_saved));
+
   - id: radio_step
     mode: queued
     parameters:
@@ -682,19 +726,32 @@ select:
       sorting_group_id: group_snooze
       sorting_weight: 3
 
-  - platform: tuya
+  - platform: template
     id: ambient_color
     name: "Ambient Color"
-    enum_datapoint: 132
     options:
-      0: "Cycle"
-      1: "Red"
-      2: "Orange"
-      3: "Yellow"
-      4: "Green"
-      5: "Cyan"
-      6: "Blue"
-      7: "Purple"
+      - "Cycle"
+      - "Red"
+      - "Orange"
+      - "Yellow"
+      - "Green"
+      - "Cyan"
+      - "Blue"
+      - "Purple"
+    update_interval: 1s
+    lambda: |-
+      static const char *const names[8] = {"Cycle", "Red", "Orange", "Yellow", "Green", "Cyan", "Blue", "Purple"};
+      if (id(ambient_color_now) > 7) return {};
+      return std::string(names[id(ambient_color_now)]);
+    set_action:
+      - lambda: |-
+          static const char *const names[8] = {"Cycle", "Red", "Orange", "Yellow", "Green", "Cyan", "Blue", "Purple"};
+          for (uint8_t i = 0; i < 8; i++) {
+            if (x == names[i]) {
+              id(ambient_color_saved) = i;
+              id(tuya_mcu).set_enum_datapoint_value(132, i);
+            }
+          }
     web_server:
       sorting_group_id: group_light
       sorting_weight: 3