From 6fb61a85bb9504a5f2fed774884f9bea7aceb123 Mon Sep 17 00:00:00 2001
From: Adam Wonak <adam.wonak@gmail.com>
Date: Sun, 20 Jul 2025 10:39:44 -0700
Subject: [PATCH] When loading EEPROM, if the metadata is not valid, erase all
 EEPROM.

---
 firmware/Gravity/save_state.cpp | 12 +++++++++++-
 firmware/Gravity/save_state.h   |  6 ++++--
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/firmware/Gravity/save_state.cpp b/firmware/Gravity/save_state.cpp
index 052779b..16ef342 100644
--- a/firmware/Gravity/save_state.cpp
+++ b/firmware/Gravity/save_state.cpp
@@ -26,7 +26,8 @@ bool StateManager::initialize(AppState& app) {
         return loadData(app, MAX_SAVE_SLOTS);
     } else {
         // EEPROM does not contain save data for this firmware & version.
-        // Initialize eeprom and save default patter to all save slots.
+        // Erase EEPROM and initialize state. Save default pattern to all save slots.
+        factoryReset();
         reset(app);
         _saveMetadata();
         // MAX_SAVE_SLOTS slot is reserved for transient state.
@@ -82,6 +83,15 @@ void StateManager::markDirty() {
     _lastChangeTime = millis();
 }
 
+// Erases all data in the EEPROM by writing 0 to every address.
+void StateManager::factoryReset() {
+    noInterrupts();
+    for (unsigned int i = 0 ; i < EEPROM.length() ; i++) {
+        EEPROM.write(i, 0);
+    }
+    interrupts();
+}
+
 bool StateManager::_isDataValid() {
     Metadata load_meta;
     EEPROM.get(0, load_meta);
diff --git a/firmware/Gravity/save_state.h b/firmware/Gravity/save_state.h
index 354253a..29ae845 100644
--- a/firmware/Gravity/save_state.h
+++ b/firmware/Gravity/save_state.h
@@ -19,8 +19,8 @@
 struct AppState;
 
 // Define the constants for the current firmware.
-const char SKETCH_NAME[] = "Gravity";
-const byte SKETCH_VERSION = 7;
+const char SKETCH_NAME[] = "AltGravity";
+const byte SKETCH_VERSION = 1;
 
 // Number of available save slots.
 const byte MAX_SAVE_SLOTS = 10;
@@ -52,6 +52,8 @@ class StateManager {
     void update(const AppState& app);
     // Indicate that state has changed and we should save.
     void markDirty();
+    // Erase all data stored in the EEPROM.
+    void factoryReset();
 
     // This struct holds the data that identifies the firmware version.
     struct Metadata {