refactor(driver): simplify and harden espnow message handlers

src/main.py

@@ -14,18 +14,13 @@ presets = Presets(settings["led_pin"], settings["num_leds"])
 presets.load(settings)
 presets.b = settings.get("brightness", 255)
 # Use the default preset name from settings (set via controller or defaults)
-default_preset = settings.get("default")
-if (
-    isinstance(default_preset, str)
-    and default_preset
-    and default_preset in presets.presets
-):
+default_preset = settings.get("default", "")
+if default_preset and default_preset in presets.presets:
     presets.select(default_preset)
     print(f"Selected startup preset: {default_preset}")
 
 wdt = WDT(timeout=10000)
 wdt.feed()
-last_brightness_save = 0
 
 sta_if = network.WLAN(network.STA_IF)
 sta_if.active(True)
@@ -35,87 +30,95 @@ e = ESPNow()
 e.active(True)
 
 
+def as_dict(value):
+    return value if isinstance(value, dict) else {}
+
+
+def as_list(value):
+    return value if isinstance(value, list) else []
+
+
+def receive_data(receiver):
+    """Read one ESPNow message and decode JSON dict payload."""
+    try:
+        host, msg = receiver.recv()
+        data = json.loads(msg)
+        print(msg)
+        data = as_dict(data)
+        if data.get("v", "") != "1":
+            return None
+        return data
+    except (ValueError, TypeError):
+        return None
+
+
+def apply_brightness(data):
+    """Apply and persist global brightness from payload."""
+    try:
+        presets.b = max(0, min(255, int(data["b"])))
+        settings["brightness"] = presets.b
+    except (TypeError, ValueError):
+        pass
+
+
+def apply_presets(data):
+    """Create/update preset definitions from payload."""
+    presets_map = as_dict(data.get("presets"))
+    for id, preset_data in presets_map.items():
+        preset_data = as_dict(preset_data)
+        if not preset_data:
+            continue
+        color_key = "c" if "c" in preset_data else ("colors" if "colors" in preset_data else None)
+        if color_key is not None:
+            try:
+                preset_data[color_key] = convert_and_reorder_colors(
+                    preset_data[color_key], settings
+                )
+            except (TypeError, ValueError, KeyError):
+                continue
+        presets.edit(id, preset_data)
+        print(f"Edited preset {id}: {preset_data.get('name', '')}")
+
+
+def apply_select(data):
+    """Select preset for this device when addressed."""
+    select_map = as_dict(data.get("select"))
+    device_name = settings["name"]
+
+    # Case-sensitive: select key must match device name exactly.
+    select_list = as_list(select_map.get(device_name))
+    if not select_list:
+        return
+    preset_name = select_list[0]
+    step = select_list[1] if len(select_list) > 1 else None
+    if isinstance(preset_name, str):
+        presets.select(preset_name, step=step)
+
+
+def apply_default(data):
+    targets = as_list(data.get("targets"))
+    default_name = data.get("default", "")
+    if (
+        settings["name"] in targets
+        and isinstance(default_name, str)
+        and default_name in presets.presets
+    ):
+        settings["default"] = default_name
+
+
 while True:
     wdt.feed()
     presets.tick()
     if e.any():
-        try:
-            host, msg = e.recv()
-            data = json.loads(msg)
-            print(msg)
-        except (ValueError, TypeError):
+        if (data := receive_data(e)) is None:
             continue
-        if not isinstance(data, dict):
-            continue
-        # Only handle messages with the expected version.
-        if data.get("v") != "1":
-            continue
-        # print(data)
-        # Global brightness (0–255) for this device
         if "b" in data:
-            try:
-                presets.b = max(0, min(255, int(data["b"])))
-                settings["brightness"] = presets.b
-                now = utime.ticks_ms()
-                if utime.ticks_diff(now, last_brightness_save) >= 500:
-                    settings.save()
-                    last_brightness_save = now
-            except (TypeError, ValueError):
-                pass
-        if isinstance(data.get("presets"), dict):
-            for id, preset_data in data["presets"].items():
-                if not isinstance(preset_data, dict):
-                    continue
-                # Convert hex color strings to RGB tuples and reorder based on device colour order.
-                color_key = "c" if "c" in preset_data else ("colors" if "colors" in preset_data else None)
-                if color_key is not None:
-                    try:
-                        preset_data[color_key] = convert_and_reorder_colors(
-                            preset_data[color_key], settings
-                        )
-                    except (TypeError, ValueError):
-                        continue
-                presets.edit(id, preset_data)
-                print(f"Edited preset {id}: {preset_data.get('name', '')}")
-        if isinstance(data.get("select"), dict) and settings.get("name") in data["select"]:
-            select_list = data["select"][settings.get("name")]
-            # Select value is always a list: ["preset_name"] or ["preset_name", step]
-            if isinstance(select_list, list) and select_list:
-                preset_name = select_list[0]
-                step = select_list[1] if len(select_list) > 1 else None
-                if isinstance(preset_name, str):
-                    presets.select(preset_name, step=step)
+            apply_brightness(data)
+        if "presets" in data:
+            apply_presets(data)
+        if "select" in data:
+            apply_select(data)
         if "default" in data:
-            default_name = data["default"]
-            this_device_name = settings.get("name")
-            this_device_name_norm = (
-                this_device_name.strip().lower()
-                if isinstance(this_device_name, str)
-                else None
-            )
-            should_apply_default = True
-            if "targets" in data:
-                # When targets are present, default must only apply to named targets.
-                should_apply_default = False
-                targets = data.get("targets")
-                if isinstance(targets, list) and this_device_name_norm:
-                    normalized_targets = [
-                        target.strip().lower()
-                        for target in targets
-                        if isinstance(target, str) and target.strip()
-                    ]
-                    should_apply_default = this_device_name_norm in normalized_targets
-                if not should_apply_default:
-                    print("Ignored default: device not in targets")
-            if (
-                should_apply_default
-                and
-                isinstance(default_name, str)
-                and default_name
-                and default_name in presets.presets
-            ):
-                settings["default"] = default_name
-                print(f"Set startup preset to: {default_name}")
-                settings.save()
-        if "save" in data:
+            apply_default(data)
+        if "save" in data and ("presets" in data or "default" in data):
             presets.save()