Added basic theming engine.

This theming engine uses a bytestring (but supports anything indexable,
as long as the index results are a byte long),
stored as `wasp.system._theme`.
It has a default value, which should not change anything about the way this looks currently.

The theme can be set via `wasp.system.set_theme`,
but this should *ONLY* be used in `main.py`.
`wasp.system.set_theme` will return True if it was successful,
or False if the theme is of an old format.
Using an old format theme will *not* crash the watch,
but will use the default theme instead.

To theme this, one has to use tools/themer.py (use flag -h for complete explanation)
to generate a bytestring that's added in main.py (see diff).

The bytestring is then loaded into 'wasp.system._theme'.
Theme values can be looked up by apps by using `wasp.system.theme("theme-key")`.
Theme keys appear in the function body of `wasp.system.theme()`.

I've took the liberty of converting existing apps to use this method,
and it seems to work well.

A test theme is provided in `tools/test_theme.py`

Signed-off-by: kozova1 <mug66kk@gmail.com>

1 files changed, 28 insertions, 1 deletions

diff --git a/wasp/wasp.py b/wasp/wasp.py
index 7cf2883..4837e12 100644
--- a/wasp/wasp.py
+++ b/wasp/wasp.py
@@ -14,7 +14,6 @@
     wasp.watch is an import of :py:mod:`watch` and is simply provided as a
     shortcut (and to reduce memory by keeping it out of other namespaces).
 """
-
 import gc
 import machine
 import micropython
@@ -118,6 +117,8 @@ class Manager():
         self.musicstate = {}
         self.musicinfo = {}
 
+        self._theme = b'\xef{\xef{\xef{<\xe7\xef{\xb6\xb5\xb6\xbd\xff\xff\xff9'
+
         self.blank_after = 15
 
         self._alarms = []
@@ -514,4 +515,30 @@ class Manager():
 
         self._scheduling = enable
 
+    def set_theme(self, new_theme) -> bool:
+        """Sets the system theme.
+
+        Accepts anything that supports indexing,
+        and has a len() equivalent to the default theme."""
+        if len(self._theme) != len(new_theme):
+            return False
+        self._theme = new_theme
+        return True
+
+    def theme(self, theme_part: str) -> int:
+        """Returns the relevant part of theme. For more see ../tools/themer.py"""
+        theme_parts = ("ble",
+                       "scroll-indicator",
+                       "battery-charging",
+                       "status-clock",
+                       "notify-icon",
+                       "accent-mid",
+                       "accent-lo",
+                       "accent-hi",
+                       "slider-default")
+        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)
+
 system = Manager()