Add `kotlinx.serialization-json` dependencies

app/build.gradle

@@ -4,6 +4,7 @@ plugins {
     id 'kotlin-kapt'
     id 'dagger.hilt.android.plugin'
     id 'idea'
+    id 'org.jetbrains.kotlin.plugin.serialization' version "$kotlin_version"
 }
 
 idea.module {
@@ -108,7 +109,7 @@ android {
 
 dependencies {
     /* Google  */
-    implementation "androidx.core:core-ktx:1.7.0"
+    implementation 'androidx.core:core-ktx:1.7.0'
     implementation 'androidx.appcompat:appcompat:1.4.1'
     implementation 'androidx.constraintlayout:constraintlayout:2.1.3'
     implementation 'androidx.preference:preference-ktx:1.2.0'
@@ -123,7 +124,8 @@ dependencies {
     implementation 'com.google.android.flexbox:flexbox:3.0.0'
 
     /* Kotlin */
-    implementation("org.jetbrains.kotlin:kotlin-reflect:1.6.20")
+    implementation "org.jetbrains.kotlin:kotlin-reflect:$kotlin_version"
+    implementation "org.jetbrains.kotlinx:kotlinx-serialization-json:$serialization_version"
 
     /* JetBrains */
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"

app/proguard-rules.pro

@@ -6,3 +6,31 @@
 -keep class emu.skyline.** { *; }
 # Keep kotlin classes so that kotlin reflection works
 -keep class kotlin.** {*;}
+
+# https://github.com/Kotlin/kotlinx.serialization#android
+# Keep `Companion` object fields of serializable classes.
+# This avoids serializer lookup through `getDeclaredClasses` as done for named companion objects.
+-if @kotlinx.serialization.Serializable class **
+-keepclassmembers class <1> {
+    static <1>$Companion Companion;
+}
+
+# Keep `serializer()` on companion objects (both default and named) of serializable classes.
+-if @kotlinx.serialization.Serializable class ** {
+    static **$* *;
+}
+-keepclassmembers class <2>$<3> {
+    kotlinx.serialization.KSerializer serializer(...);
+}
+
+# Keep `INSTANCE.serializer()` of serializable objects.
+-if @kotlinx.serialization.Serializable class ** {
+    public static ** INSTANCE;
+}
+-keepclassmembers class <1> {
+    public static <1> INSTANCE;
+    kotlinx.serialization.KSerializer serializer(...);
+}
+
+# @Serializable and @Polymorphic are used at runtime for polymorphic serialization.
+-keepattributes RuntimeVisibleAnnotations,AnnotationDefault

build.gradle

@@ -3,6 +3,7 @@
 buildscript {
     ext {
         kotlin_version = '1.6.21'
+        serialization_version = '1.3.3'
         lifecycle_version = '2.4.1'
         hilt_version = '2.41'
     }