Introduce StateManager class for persisting state to EEPROM.

examples/Gravity/save_state.cpp

@@ -0,0 +1,85 @@
+// File: save_state.cpp
+
+#include <EEPROM.h>
+#include "save_state.h"
+#include "app_state.h" // Includes AppState and Channel definitions
+
+bool StateManager::initialize(AppState& app) {
+    if (isDataValid()) {
+        EepromData loadedState;
+        EEPROM.get(sizeof(Metadata), loadedState);
+        
+        // Restore main app state
+        app.selected_param = loadedState.selected_param;
+        app.selected_channel = loadedState.selected_channel;
+        app.selected_source = static_cast<Source>(loadedState.selected_source);
+        
+        // --- NEW: Loop through and restore each channel's state ---
+        for (int i = 0; i < OUTPUT_COUNT; i++) {
+            auto& ch = app.channel[i]; // Get a reference to the channel object
+            const auto& saved_ch_state = loadedState.channel_data[i]; // Get a const reference to the saved data
+
+            ch.setClockMod(saved_ch_state.base_clock_mod_index);
+            ch.setProbability(saved_ch_state.base_probability);
+            ch.setDutyCycle(saved_ch_state.base_duty_cycle);
+            ch.setOffset(saved_ch_state.base_offset);
+            ch.setCvSource(static_cast<CvSource>(saved_ch_state.cv_source));
+            ch.setCvDestination(static_cast<CvDestination>(saved_ch_state.cv_destination));
+        }
+        
+        return true;
+    } else {
+        writeMetadata();
+        save(app); // Save the initial default state
+        return false;
+    }
+}
+
+void StateManager::save(const AppState& app) {
+    EepromData stateToSave;
+    
+    // Populate main app state
+    stateToSave.selected_param = app.selected_param;
+    stateToSave.selected_channel = app.selected_channel;
+    stateToSave.selected_source = static_cast<byte>(app.selected_source);
+
+    // --- NEW: Loop through and populate each channel's state ---
+    for (int i = 0; i < OUTPUT_COUNT; i++) {
+        const auto& ch = app.channel[i]; // Get a const reference to the channel object
+        auto& saved_ch_state = stateToSave.channel_data[i]; // Get a reference to the struct we're saving to
+
+        // Use the getters with 'withCvMod = false' to get the base values
+        saved_ch_state.base_clock_mod_index = ch.getClockModIndex(false);
+        saved_ch_state.base_probability = ch.getProbability(false);
+        saved_ch_state.base_duty_cycle = ch.getDutyCycle(false);
+        saved_ch_state.base_offset = ch.getOffset(false);
+        saved_ch_state.cv_source = static_cast<byte>(ch.getCvSource());
+        saved_ch_state.cv_destination = static_cast<byte>(ch.getCvDestination());
+    }
+
+    // Write the entire state struct to EEPROM
+    EEPROM.put(sizeof(Metadata), stateToSave);
+}
+
+void StateManager::reset(AppState& app) {
+    AppState defaultState;
+    app = defaultState;
+    writeMetadata();
+    save(app);
+}
+
+// isDataValid() and writeMetadata() remain unchanged
+bool StateManager::isDataValid() {
+    Metadata storedMeta;
+    EEPROM.get(0, storedMeta);
+    bool nameMatch = (strcmp(storedMeta.sketchName, CURRENT_SKETCH_NAME) == 0);
+    bool versionMatch = (storedMeta.version == CURRENT_SKETCH_VERSION);
+    return nameMatch && versionMatch;
+}
+
+void StateManager::writeMetadata() {
+    Metadata currentMeta;
+    strcpy(currentMeta.sketchName, CURRENT_SKETCH_NAME);
+    currentMeta.version = CURRENT_SKETCH_VERSION;
+    EEPROM.put(0, currentMeta);
+}