wasp: manager: Byte-swap the theme encoding

Currently the theme is explicitly little endian. This does match the
underlying hardware but makes it needlessly difficult to hand edit
themes. Switch the default theme and theming tools over to big endian
form and add comments to the default theme to support hand editing.

We also expand the ASCII characters in the default them with hex codes.
This is the final step needed to make hand edited themes trivial to work
with.

Signed-off-by: Daniel Thompson <daniel@redfelineninja.org.uk>

tools/themer.py

@@ -25,7 +25,7 @@ class DefaultTheme():
     def serialize(self) -> bytes:
         """Serializes the theme for use in wasp-os"""
         def split_bytes(x: int) -> Tuple[int, int]:
-            return (x & 0xFF, (x >> 8) & 0xFF)
+            return ((x >> 8) & 0xFF, x & 0xFF)
         theme_bytes = bytes([
             *split_bytes(self.BLE_COLOR),
             *split_bytes(self.SCROLL_INDICATOR_COLOR),

wasp/wasp.py

@@ -117,7 +117,17 @@ class Manager():
         self.musicstate = {}
         self.musicinfo = {}
 
-        self._theme = b'\xef{\xef{\xef{<\xe7\xef{\xb6\xb5\xb6\xbd\xff\xff\xff9'
+        self._theme = (
+                b'\x7b\xef'     # ble
+                b'\x7b\xef'     # scroll-indicator
+                b'\x7b\xef'     # battery
+                b'\xe7\x3c'     # status-clock
+                b'\x7b\xef'     # notify-icon
+                b'\xb5\xb6'     # accent-mid
+                b'\xbd\xb6'     # accent-lo
+                b'\xff\xff'     # accent-hi
+                b'\x39\xff'     # slider-default
+        )
 
         self.blank_after = 15
 
@@ -539,6 +549,6 @@ class Manager():
         if theme_part not in theme_parts:
             raise IndexError('Theme part {} does not exist'.format(theme_part))
         idx = theme_parts.index(theme_part) * 2
-        return self._theme[idx] | (self._theme[idx+1] << 8)
+        return (self._theme[idx] << 8) | self._theme[idx+1]
 
 system = Manager()