Recover from corrupted config by reinstating the default config

I've seen a few users run into this (mostly before we saved the
config with a different name and then moved it) but I'd like to
have this fallback either way so their game at can start again.

platforms/common/src/main/java/dynamic_fps/impl/config/DynamicFPSConfig.java

@@ -14,7 +14,7 @@ public final class DynamicFPSConfig {
 	@SerializedName("states")
 	private final Map<PowerState, Config> configs;
 
-	DynamicFPSConfig(boolean enabled, int abandonTime, boolean uncapMenuFrameRate, Map<PowerState, Config> configs) {
+	private DynamicFPSConfig(boolean enabled, int abandonTime, boolean uncapMenuFrameRate, Map<PowerState, Config> configs) {
 		this.enabled = enabled;
 		this.idleTime = abandonTime;
 		this.uncapMenuFrameRate = uncapMenuFrameRate;
@@ -28,6 +28,18 @@ public final class DynamicFPSConfig {
 		}
 	}
 
+	public static DynamicFPSConfig createDefault() {
+		DynamicFPSConfig instance =  new DynamicFPSConfig(
+			true,
+			0,
+			false,
+			new EnumMap<>(PowerState.class)
+		);
+
+		instance.save();
+		return instance;
+	}
+
 	public Config get(PowerState state) {
 		if (state == PowerState.FOCUSED) {
 			return Config.ACTIVE;

platforms/common/src/main/java/dynamic_fps/impl/config/Serialization.java

@@ -16,7 +16,7 @@
 import dynamic_fps.impl.GraphicsState;
 import dynamic_fps.impl.PowerState;
 import dynamic_fps.impl.service.Platform;
-import net.minecraft.sounds.SoundSource;
+import dynamic_fps.impl.util.Logging;
 import org.jetbrains.annotations.Nullable;
 
 import java.io.IOException;
@@ -26,7 +26,6 @@
 import java.nio.file.NoSuchFileException;
 import java.nio.file.Path;
 import java.nio.file.StandardCopyOption;
-import java.util.EnumMap;
 import java.util.Locale;
 import java.util.Map;
 
@@ -76,18 +75,18 @@ public static DynamicFPSConfig load() {
 		try {
 			data = Files.readAllBytes(config);
 		} catch (NoSuchFileException e) {
-			DynamicFPSConfig instance = new DynamicFPSConfig(
-				true,
-				0,
-				false,
-				new EnumMap<>(PowerState.class)
-			);
-			instance.save();
-			return instance;
+			return DynamicFPSConfig.createDefault();
 		} catch (IOException e) {
 			throw new RuntimeException("Failed to load Dynamic FPS config.", e);
 		}
 
+		// Sometimes when the config failed to save properly it'll end up being only null bytes.
+		// Since most users don't seem to know how to deal with this we'll just replace the config.
+		if (data[0] == 0) {
+			Logging.getLogger().warn("Dynamic FPS config corrupted! Recreating from defaults ...");
+			return DynamicFPSConfig.createDefault();
+		}
+
 		JsonElement root = new JsonParser().parse(new String(data, StandardCharsets.UTF_8));
 
 		upgradeConfig((JsonObject) root);