add settings struct

ch32v-insert-coin/src/main.rs

@@ -24,6 +24,42 @@ use hal::println;
 
 use qingke::riscv;
 
+enum Level {
+    Off,
+    Low,
+    Medium,
+    High,
+    Maximum,
+}
+
+impl Level {
+    pub fn next(&mut self) {
+        *self = match self {
+            Self::Off => Self::Low,
+            Self::Low => Self::Medium,
+            Self::Medium => Self::High,
+            Self::High => Self::Maximum,
+            Self::Maximum => Self::Off,
+        };
+    }
+}
+
+struct Settings {
+    brightness: Level,
+    volume: Level,
+    button_sound_index: u8,
+}
+
+impl Default for Settings {
+    fn default() -> Self {
+        Self {
+            brightness: Level::Medium,
+            volume: Level::Medium,
+            button_sound_index: 0,
+        }
+    }
+}
+
 struct DebouncedGPIO<'a> {
     input: Input<'a>,
     // value of the GPIO