Save current output mode to nvs

src/drivers/include/nvs.hpp

@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <stdint.h>
 #include <optional>
 
 #include "esp_err.h"
@@ -24,6 +25,13 @@ class NvsStorage {
   auto PreferredBluetoothDevice() -> std::optional<bluetooth::mac_addr_t>;
   auto PreferredBluetoothDevice(std::optional<bluetooth::mac_addr_t>) -> void;
 
+  enum class Output : uint8_t {
+    kHeadphones = 0,
+    kBluetooth = 1,
+  };
+  auto OutputMode() -> Output;
+  auto OutputMode(Output) -> void;
+
   explicit NvsStorage(nvs_handle_t);
   ~NvsStorage();
 

src/drivers/nvs.cpp

@@ -22,6 +22,7 @@ static constexpr uint8_t kSchemaVersion = 1;
 
 static constexpr char kKeyVersion[] = "ver";
 static constexpr char kKeyBluetooth[] = "bt";
+static constexpr char kKeyOutput[] = "out";
 
 auto NvsStorage::Open() -> NvsStorage* {
   esp_err_t err = nvs_flash_init();
@@ -81,6 +82,7 @@ auto NvsStorage::PreferredBluetoothDevice()
   }
   return out;
 }
+
 auto NvsStorage::PreferredBluetoothDevice(
     std::optional<bluetooth::mac_addr_t> addr) -> void {
   if (!addr) {
@@ -92,4 +94,21 @@ auto NvsStorage::PreferredBluetoothDevice(
   nvs_commit(handle_);
 }
 
+auto NvsStorage::OutputMode() -> Output {
+  uint8_t out = 0;
+  nvs_get_u8(handle_, kKeyOutput, &out);
+  switch (out) {
+    case static_cast<uint8_t>(Output::kBluetooth):
+      return Output::kHeadphones;
+    case static_cast<uint8_t>(Output::kHeadphones):
+    default:
+      return Output::kHeadphones;
+  }
+}
+
+auto NvsStorage::OutputMode(Output out) -> void {
+  nvs_set_u8(handle_, kKeyOutput, static_cast<uint8_t>(out));
+  nvs_commit(handle_);
+}
+
 }  // namespace drivers