refactor: replace Gson to kotlin serialization

app/build.gradle.kts

@@ -1,6 +1,7 @@
 plugins {
     id("com.android.application")
-    id("kotlin-android")
+    kotlin("android")
+    kotlin("plugin.serialization") version "1.8.0"
 }
 
 repositories {
@@ -17,7 +18,7 @@ android {
         minSdk = 21
         targetSdk = 33
         compileSdk = 33
-        versionCode = 140
+        versionCode = 141
         versionName = "1.6.0"
         setProperty("archivesBaseName", "$applicationId-v$versionName")
     }
@@ -44,5 +45,5 @@ dependencies {
     implementation(fileTree(mapOf("dir" to "libs", "include" to listOf("*.jar"))))
     implementation("androidx.recyclerview:recyclerview:1.3.2")
     implementation("androidx.preference:preference-ktx:1.2.1")
-    implementation("com.google.code.gson:gson:2.10.1")
+    implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.6.0")
 }

app/src/main/java/juniojsv/minimum/features/applications/ApplicationsAdapter.kt

@@ -12,12 +12,12 @@ import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.LifecycleOwner
 import androidx.recyclerview.widget.GridLayoutManager
 import androidx.recyclerview.widget.RecyclerView
-import com.google.gson.Gson
 import juniojsv.minimum.BuildConfig
 import juniojsv.minimum.databinding.ApplicationGridVariantBinding
 import juniojsv.minimum.databinding.ApplicationListVariantBinding
 import juniojsv.minimum.models.Application
 import juniojsv.minimum.models.ApplicationsGroup
+import juniojsv.minimum.utils.UUIDSerializer
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Deferred
 import kotlinx.coroutines.Dispatchers
@@ -28,12 +28,20 @@ import kotlinx.coroutines.coroutineScope
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.suspendCancellableCoroutine
 import kotlinx.coroutines.withContext
+import kotlinx.serialization.Serializable
+import kotlinx.serialization.encodeToString
+import kotlinx.serialization.json.Json
 import java.util.UUID
 import kotlin.coroutines.CoroutineContext
 import kotlin.coroutines.resume
 
-private data class ApplicationState(val isPinned: Boolean, val group: UUID?)
+@Serializable
+private data class ApplicationState(
+    val isPinned: Boolean,
+    @Serializable(with = UUIDSerializer::class) val group: UUID?
+)
 
+@Serializable
 private data class ApplicationsAdapterState(
     val groups: List<ApplicationsGroup>,
     val applications: Map<String, ApplicationState>
@@ -48,7 +56,6 @@ class ApplicationsAdapter(
     ApplicationsEventsBroadcastReceiver.Callbacks, DefaultLifecycleObserver, CoroutineScope {
     private val events = ApplicationsEventsBroadcastReceiver(lifecycle, this)
     val controller = ApplicationsAdapterController(this)
-    private val gson = Gson()
     private val lastPersistedState = async {
         suspendCancellableCoroutine {
             try {
@@ -57,7 +64,7 @@ class ApplicationsAdapter(
                 val json = reader.readText()
                 reader.close()
                 file.close()
-                it.resume(gson.fromJson(json, ApplicationsAdapterState::class.java))
+                it.resume(Json.decodeFromString<ApplicationsAdapterState>(json))
             } catch (e: Throwable) {
                 it.resume(null)
             }
@@ -95,7 +102,7 @@ class ApplicationsAdapter(
                 }
             )
             val file = context.openFileOutput(STATE_FILE_NAME, Context.MODE_PRIVATE)
-            file.write(gson.toJson(state).toByteArray())
+            file.write(Json.encodeToString(state).toByteArray())
             file.close()
         }
     }

app/src/main/java/juniojsv/minimum/models/Application.kt

@@ -1,17 +1,16 @@
 package juniojsv.minimum.models
 
 import android.content.Intent
-import com.google.gson.annotations.SerializedName
 import java.util.UUID
 
 data class Application(
-    @SerializedName("application_label") override val label: String,
+    override val label: String,
     val packageName: String,
     val launchIntent: Intent,
     val isNew: Boolean = false,
     val isPinned: Boolean = false,
     val group: UUID? = null,
-    @SerializedName("application_id") override val id: UUID = UUID.randomUUID()
-) : ApplicationBase(label, id) {
+    override val id: UUID = UUID.randomUUID()
+) : ApplicationBase() {
     override val priority: Int = if (isPinned) 1 else 0
 }

app/src/main/java/juniojsv/minimum/models/ApplicationBase.kt

@@ -2,11 +2,11 @@ package juniojsv.minimum.models
 
 import java.util.UUID
 
-sealed class ApplicationBase(
-    open val label: String,
-    open val id: UUID
-) :
+sealed class ApplicationBase :
     Comparable<ApplicationBase> {
+    abstract val label: String
+    abstract val id: UUID
+
     /**
      * Sorting priority
      */

app/src/main/java/juniojsv/minimum/models/ApplicationsGroup.kt

@@ -1,16 +1,18 @@
 package juniojsv.minimum.models
 
-import com.google.gson.annotations.SerializedName
+import juniojsv.minimum.utils.UUIDSerializer
+import kotlinx.serialization.Serializable
 import java.util.UUID
 
 /**
  * @param mergeWith is the id of target [ApplicationsGroup] to move all items of this group
  */
+@Serializable
 data class ApplicationsGroup(
-    @SerializedName("group_label") override val label: String,
-    @SerializedName("group_id") override val id: UUID = UUID.randomUUID(),
+    override val label: String,
+    @Serializable(with = UUIDSerializer::class) override val id: UUID = UUID.randomUUID(),
     val isPinned: Boolean,
-    val mergeWith: UUID? = null
-) : ApplicationBase(label, id) {
+    @Serializable(with = UUIDSerializer::class) val mergeWith: UUID? = null
+) : ApplicationBase() {
     override val priority: Int = if (isPinned) 1 else 0
 }

app/src/main/java/juniojsv/minimum/utils/UUIDSerializer.kt

@@ -0,0 +1,20 @@
+package juniojsv.minimum.utils
+
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.descriptors.PrimitiveKind
+import kotlinx.serialization.descriptors.PrimitiveSerialDescriptor
+import kotlinx.serialization.encoding.Decoder
+import kotlinx.serialization.encoding.Encoder
+import java.util.UUID
+
+object UUIDSerializer : KSerializer<UUID> {
+    override val descriptor = PrimitiveSerialDescriptor("UUID", PrimitiveKind.STRING)
+
+    override fun deserialize(decoder: Decoder): UUID {
+        return UUID.fromString(decoder.decodeString())
+    }
+
+    override fun serialize(encoder: Encoder, value: UUID) {
+        encoder.encodeString(value.toString())
+    }
+}