Move from Gson to Kotlin Serialization for definitions

19 files changed, 153 insertions, 262 deletions

diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/cards/Requirements.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/cards/Requirements.kt
index b78a5057..1d03aa76 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/cards/Requirements.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/cards/Requirements.kt
@@ -1,11 +1,13 @@
 package org.luxons.sevenwonders.engine.cards
 
+import kotlinx.serialization.Serializable
 import org.luxons.sevenwonders.engine.Player
 import org.luxons.sevenwonders.engine.boards.Board
 import org.luxons.sevenwonders.engine.resources.*
 import org.luxons.sevenwonders.model.resources.ResourceTransactions
 import org.luxons.sevenwonders.model.resources.bestPrice
 
+@Serializable
 data class Requirements internal constructor(
     val gold: Int = 0,
     val resources: Resources = emptyResources(),
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/GameDefinition.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/GameDefinition.kt
index 07c101e6..64d6be3b 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/GameDefinition.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/GameDefinition.kt
@@ -1,34 +1,20 @@
 package org.luxons.sevenwonders.engine.data
 
-import com.github.salomonbrys.kotson.typeToken
-import com.google.gson.Gson
-import com.google.gson.GsonBuilder
+import kotlinx.serialization.Serializable
+import kotlinx.serialization.decodeFromString
+import kotlinx.serialization.json.Json
 import org.luxons.sevenwonders.engine.Game
 import org.luxons.sevenwonders.engine.boards.Board
 import org.luxons.sevenwonders.engine.data.definitions.DecksDefinition
 import org.luxons.sevenwonders.engine.data.definitions.WonderDefinition
-import org.luxons.sevenwonders.engine.data.serializers.NumericEffectSerializer
-import org.luxons.sevenwonders.engine.data.serializers.ProductionIncreaseSerializer
-import org.luxons.sevenwonders.engine.data.serializers.ProductionSerializer
-import org.luxons.sevenwonders.engine.data.serializers.ResourceTypeSerializer
-import org.luxons.sevenwonders.engine.data.serializers.ResourceTypesSerializer
-import org.luxons.sevenwonders.engine.data.serializers.ResourcesSerializer
-import org.luxons.sevenwonders.engine.data.serializers.ScienceProgressSerializer
-import org.luxons.sevenwonders.engine.effects.GoldIncrease
-import org.luxons.sevenwonders.engine.effects.MilitaryReinforcements
-import org.luxons.sevenwonders.engine.effects.ProductionIncrease
-import org.luxons.sevenwonders.engine.effects.RawPointsIncrease
-import org.luxons.sevenwonders.engine.effects.ScienceProgress
-import org.luxons.sevenwonders.engine.resources.Production
-import org.luxons.sevenwonders.engine.resources.Resources
 import org.luxons.sevenwonders.model.Age
 import org.luxons.sevenwonders.model.Settings
-import org.luxons.sevenwonders.model.resources.ResourceType
 import org.luxons.sevenwonders.model.wonders.AssignedWonder
 import org.luxons.sevenwonders.model.wonders.PreGameWonder
 
 internal const val LAST_AGE: Age = 3
 
+@Serializable
 internal data class GlobalRules(
     val minPlayers: Int,
     val maxPlayers: Int,
@@ -63,36 +49,18 @@ class GameDefinition internal constructor(
     companion object {
 
         fun load(): GameDefinition {
-            val gson: Gson = createGson()
-            val rules = loadJson("global_rules.json", GlobalRules::class.java, gson)
-            val wonders = loadJson("wonders.json", Array<WonderDefinition>::class.java, gson)
-            val decksDefinition = loadJson("cards.json", DecksDefinition::class.java, gson)
+            val rules = loadJson<GlobalRules>("global_rules.json")
+            val wonders = loadJson<Array<WonderDefinition>>("wonders.json")
+            val decksDefinition = loadJson<DecksDefinition>("cards.json")
             return GameDefinition(rules, wonders.toList(), decksDefinition)
         }
     }
 }
 
-private fun <T> loadJson(filename: String, clazz: Class<T>, gson: Gson): T {
+private inline fun <reified T> loadJson(filename: String): T {
     val packageAsPath = GameDefinition::class.java.`package`.name.replace('.', '/')
     val resourcePath = "/$packageAsPath/$filename"
     val resource = GameDefinition::class.java.getResource(resourcePath)
     val json = resource.readText()
-    return gson.fromJson(json, clazz)
+    return Json.decodeFromString(json)
 }
-
-private fun createGson(): Gson {
-    return GsonBuilder().disableHtmlEscaping()
-        .registerTypeAdapter<Resources>(ResourcesSerializer())
-        .registerTypeAdapter<ResourceType>(ResourceTypeSerializer())
-        .registerTypeAdapter<List<ResourceType>>(ResourceTypesSerializer())
-        .registerTypeAdapter<Production>(ProductionSerializer())
-        .registerTypeAdapter<ProductionIncrease>(ProductionIncreaseSerializer())
-        .registerTypeAdapter<MilitaryReinforcements>(NumericEffectSerializer())
-        .registerTypeAdapter<RawPointsIncrease>(NumericEffectSerializer())
-        .registerTypeAdapter<GoldIncrease>(NumericEffectSerializer())
-        .registerTypeAdapter<ScienceProgress>(ScienceProgressSerializer())
-        .create()
-}
-
-private inline fun <reified T : Any> GsonBuilder.registerTypeAdapter(typeAdapter: Any): GsonBuilder =
-    this.registerTypeAdapter(typeToken<T>(), typeAdapter)
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/CardDefinition.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/CardDefinition.kt
index cc42641a..0b9fbb7d 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/CardDefinition.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/CardDefinition.kt
@@ -1,21 +1,23 @@
 package org.luxons.sevenwonders.engine.data.definitions
 
+import kotlinx.serialization.Serializable
 import org.luxons.sevenwonders.engine.cards.Card
 import org.luxons.sevenwonders.engine.cards.Requirements
 import org.luxons.sevenwonders.model.cards.CardBack
 import org.luxons.sevenwonders.model.cards.Color
 
+@Serializable
 internal class CardDefinition(
     private val name: String,
     private val color: Color,
-    private val requirements: Requirements?,
     private val effect: EffectsDefinition,
-    private val chainParent: String?,
-    private val chainChildren: List<String>?,
+    private val requirements: Requirements? = null,
+    private val chainParent: String? = null,
+    private val chainChildren: List<String>? = null,
+    private val countPerNbPlayer: Map<Int, Int>? = null,
     private val image: String,
-    private val countPerNbPlayer: Map<Int, Int>,
 ) {
-    fun create(back: CardBack, nbPlayers: Int): List<Card> = List(countPerNbPlayer[nbPlayers] ?: 0) { create(back) }
+    fun create(back: CardBack, nbPlayers: Int): List<Card> = List(countPerNbPlayer!![nbPlayers] ?: 0) { create(back) }
 
     fun create(back: CardBack): Card {
         val reqs = requirements ?: Requirements()
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/DecksDefinition.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/DecksDefinition.kt
index f3dc42f4..ed2b1214 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/DecksDefinition.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/DecksDefinition.kt
@@ -1,17 +1,20 @@
 package org.luxons.sevenwonders.engine.data.definitions
 
+import kotlinx.serialization.Serializable
 import org.luxons.sevenwonders.engine.cards.Card
 import org.luxons.sevenwonders.engine.cards.Decks
 import org.luxons.sevenwonders.model.cards.CardBack
 import kotlin.random.Random
 
+@Serializable
 internal class DeckDefinition(
     val cards: List<CardDefinition>,
     val backImage: String,
 ) {
-    fun create(nbPlayers: Int): List<Card> = cards.flatMap { it.create(CardBack(backImage), nbPlayers) }
+    fun prepareFor(nbPlayers: Int): List<Card> = cards.flatMap { it.create(CardBack(backImage), nbPlayers) }
 }
 
+@Serializable
 internal class DecksDefinition(
     private val age1: DeckDefinition,
     private val age2: DeckDefinition,
@@ -20,9 +23,9 @@ internal class DecksDefinition(
 ) {
     fun prepareDecks(nbPlayers: Int, random: Random) = Decks(
         mapOf(
-            1 to age1.create(nbPlayers).shuffled(random),
-            2 to age2.create(nbPlayers).shuffled(random),
-            3 to (age3.create(nbPlayers) + pickGuildCards(nbPlayers, random)).shuffled(random),
+            1 to age1.prepareFor(nbPlayers).shuffled(random),
+            2 to age2.prepareFor(nbPlayers).shuffled(random),
+            3 to (age3.prepareFor(nbPlayers) + pickGuildCards(nbPlayers, random)).shuffled(random),
         ),
     )
 
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/EffectsDefinition.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/EffectsDefinition.kt
index 86829eca..efd92c90 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/EffectsDefinition.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/EffectsDefinition.kt
@@ -1,5 +1,6 @@
 package org.luxons.sevenwonders.engine.data.definitions
 
+import kotlinx.serialization.Serializable
 import org.luxons.sevenwonders.engine.effects.BonusPerBoardElement
 import org.luxons.sevenwonders.engine.effects.Discount
 import org.luxons.sevenwonders.engine.effects.Effect
@@ -11,24 +12,25 @@ import org.luxons.sevenwonders.engine.effects.ScienceProgress
 import org.luxons.sevenwonders.engine.effects.SpecialAbility
 import org.luxons.sevenwonders.engine.effects.SpecialAbilityActivation
 
+@Serializable
 internal class EffectsDefinition(
-    private val gold: GoldIncrease? = null,
-    private val military: MilitaryReinforcements? = null,
+    private val gold: Int? = null,
+    private val military: Int? = null,
     private val science: ScienceProgress? = null,
     private val discount: Discount? = null,
     private val perBoardElement: BonusPerBoardElement? = null,
     private val production: ProductionIncrease? = null,
-    private val points: RawPointsIncrease? = null,
+    private val points: Int? = null,
     private val action: SpecialAbility? = null,
 ) {
     fun create(): List<Effect> = mutableListOf<Effect>().apply {
-        gold?.let { add(it) }
-        military?.let { add(it) }
+        gold?.let { add(GoldIncrease(it)) }
+        military?.let { add(MilitaryReinforcements(it)) }
         science?.let { add(it) }
         discount?.let { add(it) }
         perBoardElement?.let { add(it) }
         production?.let { add(it) }
-        points?.let { add(it) }
+        points?.let { add(RawPointsIncrease(it)) }
         action?.let { add(SpecialAbilityActivation(it)) }
     }
 }
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/WonderDefinition.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/WonderDefinition.kt
index 2a59f6dc..3d9956bc 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/WonderDefinition.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/definitions/WonderDefinition.kt
@@ -1,12 +1,15 @@
 package org.luxons.sevenwonders.engine.data.definitions
 
+import kotlinx.serialization.Serializable
 import org.luxons.sevenwonders.engine.cards.Requirements
+import org.luxons.sevenwonders.engine.data.serializers.ResourceTypeSerializer
 import org.luxons.sevenwonders.engine.wonders.Wonder
 import org.luxons.sevenwonders.engine.wonders.WonderStage
 import org.luxons.sevenwonders.model.resources.ResourceType
 import org.luxons.sevenwonders.model.wonders.WonderName
 import org.luxons.sevenwonders.model.wonders.WonderSide
 
+@Serializable
 internal class WonderDefinition(
     val name: WonderName,
     val sides: Map<WonderSide, WonderSideDefinition>,
@@ -14,7 +17,9 @@ internal class WonderDefinition(
     fun create(wonderSide: WonderSide): Wonder = sides[wonderSide]!!.createWonder(name)
 }
 
+@Serializable
 internal class WonderSideDefinition(
+    @Serializable(with = ResourceTypeSerializer::class)
     private val initialResource: ResourceType,
     private val stages: List<WonderStageDefinition>,
     val image: String,
@@ -22,6 +27,7 @@ internal class WonderSideDefinition(
     fun createWonder(name: String): Wonder = Wonder(name, initialResource, stages.map { it.create() }, image)
 }
 
+@Serializable
 internal class WonderStageDefinition(
     private val requirements: Requirements,
     private val effects: EffectsDefinition,
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/NumericEffectSerializer.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/NumericEffectSerializer.kt
deleted file mode 100644
index a149e8a0..00000000
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/NumericEffectSerializer.kt
+++ /dev/null
@@ -1,38 +0,0 @@
-package org.luxons.sevenwonders.engine.data.serializers
-
-import com.google.gson.JsonDeserializationContext
-import com.google.gson.JsonDeserializer
-import com.google.gson.JsonElement
-import com.google.gson.JsonParseException
-import com.google.gson.JsonPrimitive
-import com.google.gson.JsonSerializationContext
-import com.google.gson.JsonSerializer
-import org.luxons.sevenwonders.engine.effects.Effect
-import org.luxons.sevenwonders.engine.effects.GoldIncrease
-import org.luxons.sevenwonders.engine.effects.MilitaryReinforcements
-import org.luxons.sevenwonders.engine.effects.RawPointsIncrease
-import java.lang.reflect.Type
-
-internal class NumericEffectSerializer : JsonSerializer<Effect>, JsonDeserializer<Effect> {
-
-    override fun serialize(effect: Effect, typeOfSrc: Type, context: JsonSerializationContext): JsonElement {
-        val value: Int = when (effect) {
-            is MilitaryReinforcements -> effect.count
-            is GoldIncrease -> effect.amount
-            is RawPointsIncrease -> effect.points
-            else -> throw IllegalArgumentException("Unknown numeric effect " + effect.javaClass.name)
-        }
-        return JsonPrimitive(value)
-    }
-
-    @Throws(JsonParseException::class)
-    override fun deserialize(json: JsonElement, typeOfT: Type, context: JsonDeserializationContext): Effect {
-        val value = json.asInt
-        return when (typeOfT) {
-            MilitaryReinforcements::class.java -> MilitaryReinforcements(value)
-            GoldIncrease::class.java -> GoldIncrease(value)
-            RawPointsIncrease::class.java -> RawPointsIncrease(value)
-            else -> throw IllegalArgumentException("Unknown numeric effet " + typeOfT.typeName)
-        }
-    }
-}
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ProductionIncreaseSerializer.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ProductionIncreaseSerializer.kt
deleted file mode 100644
index dc340578..00000000
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ProductionIncreaseSerializer.kt
+++ /dev/null
@@ -1,47 +0,0 @@
-package org.luxons.sevenwonders.engine.data.serializers
-
-import com.google.gson.JsonDeserializationContext
-import com.google.gson.JsonDeserializer
-import com.google.gson.JsonElement
-import com.google.gson.JsonParseException
-import com.google.gson.JsonPrimitive
-import com.google.gson.JsonSerializationContext
-import com.google.gson.JsonSerializer
-import org.luxons.sevenwonders.engine.effects.ProductionIncrease
-import org.luxons.sevenwonders.engine.resources.Production
-import java.lang.reflect.Type
-
-internal class ProductionIncreaseSerializer : JsonSerializer<ProductionIncrease>, JsonDeserializer<ProductionIncrease> {
-
-    override fun serialize(
-        productionIncrease: ProductionIncrease,
-        typeOfSrc: Type,
-        context: JsonSerializationContext,
-    ): JsonElement {
-        val production = productionIncrease.production
-        val json = context.serialize(production)
-        return if (!json.isJsonNull && !productionIncrease.isSellable) JsonPrimitive("(${json.asString})") else json
-    }
-
-    @Throws(JsonParseException::class)
-    override fun deserialize(
-        json: JsonElement,
-        typeOfT: Type,
-        context: JsonDeserializationContext,
-    ): ProductionIncrease {
-        var prodJson = json
-
-        var resourcesStr = prodJson.asString
-        val isSellable = !resourcesStr.startsWith("(")
-        if (!isSellable) {
-            resourcesStr = unwrapBrackets(resourcesStr)
-            prodJson = JsonPrimitive(resourcesStr)
-        }
-        val production = context.deserialize<Production>(prodJson, Production::class.java)
-        return ProductionIncrease(production, isSellable)
-    }
-
-    private fun unwrapBrackets(str: String): String {
-        return str.substring(1, str.length - 1)
-    }
-}
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ProductionSerializer.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ProductionSerializer.kt
index c98f20a8..48efaedb 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ProductionSerializer.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ProductionSerializer.kt
@@ -1,53 +1,47 @@
 package org.luxons.sevenwonders.engine.data.serializers
 
-import com.google.gson.JsonDeserializationContext
-import com.google.gson.JsonDeserializer
-import com.google.gson.JsonElement
-import com.google.gson.JsonNull
-import com.google.gson.JsonParseException
-import com.google.gson.JsonSerializationContext
-import com.google.gson.JsonSerializer
+import kotlinx.serialization.ExperimentalSerializationApi
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.descriptors.PrimitiveKind
+import kotlinx.serialization.descriptors.PrimitiveSerialDescriptor
+import kotlinx.serialization.descriptors.SerialDescriptor
+import kotlinx.serialization.encoding.Decoder
+import kotlinx.serialization.encoding.Encoder
 import org.luxons.sevenwonders.engine.resources.Production
-import org.luxons.sevenwonders.engine.resources.Resources
 import org.luxons.sevenwonders.model.resources.ResourceType
-import java.lang.reflect.Type
 
-internal class ProductionSerializer : JsonSerializer<Production>, JsonDeserializer<Production> {
+internal object ProductionSerializer : KSerializer<Production> {
 
-    override fun serialize(production: Production, typeOfSrc: Type, context: JsonSerializationContext): JsonElement {
-        val fixedResources = production.getFixedResources()
-        val choices = production.getAlternativeResources()
-        return when {
-            fixedResources.isEmpty() -> serializeAsChoice(choices, context)
-            choices.isEmpty() -> serializeAsResources(fixedResources, context)
+    override val descriptor: SerialDescriptor = PrimitiveSerialDescriptor("Production", PrimitiveKind.STRING)
+
+    @OptIn(ExperimentalSerializationApi::class)
+    override fun serialize(encoder: Encoder, value: Production) {
+        val fixedResources = value.getFixedResources()
+        val choices = value.getAlternativeResources()
+        when {
+            fixedResources.isEmpty() -> choices.toChoiceString()?.let { encoder.encodeString(it) } ?: encoder.encodeNull()
+            choices.isEmpty() -> encoder.encodeSerializableValue(ResourcesSerializer, fixedResources)
             else -> throw IllegalArgumentException("Cannot serialize a production with mixed fixed resources and choices")
         }
     }
 
-    private fun serializeAsChoice(choices: List<Set<ResourceType>>, context: JsonSerializationContext): JsonElement {
-        if (choices.isEmpty()) {
-            return JsonNull.INSTANCE
+    private fun List<Set<ResourceType>>.toChoiceString(): String? {
+        if (isEmpty()) {
+            return null
         }
-        if (choices.size > 1) {
+        if (size > 1) {
             throw IllegalArgumentException("Cannot serialize a production with more than one choice")
         }
-        val str = choices[0].map { it.symbol }.joinToString("/")
-        return context.serialize(str)
-    }
-
-    private fun serializeAsResources(fixedResources: Resources, context: JsonSerializationContext): JsonElement {
-        return context.serialize(fixedResources)
+        return this[0].map { it.symbol }.joinToString("/")
     }
 
-    @Throws(JsonParseException::class)
-    override fun deserialize(json: JsonElement, typeOfT: Type, context: JsonDeserializationContext): Production {
-        val resourcesStr = json.asString
+    override fun deserialize(decoder: Decoder): Production {
+        val resourcesStr = decoder.decodeString()
         val production = Production()
         if (resourcesStr.contains("/")) {
             production.addChoice(*createChoice(resourcesStr))
         } else {
-            val fixedResources = context.deserialize<Resources>(json, Resources::class.java)
-            production.addAll(fixedResources)
+            production.addAll(ResourcesSerializer.deserializeString(resourcesStr))
         }
         return production
     }
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ResourceTypeSerializer.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ResourceTypeSerializer.kt
index b308fd24..ccbb9560 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ResourceTypeSerializer.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ResourceTypeSerializer.kt
@@ -1,26 +1,20 @@
 package org.luxons.sevenwonders.engine.data.serializers
 
-import com.google.gson.JsonDeserializationContext
-import com.google.gson.JsonDeserializer
-import com.google.gson.JsonElement
-import com.google.gson.JsonParseException
-import com.google.gson.JsonPrimitive
-import com.google.gson.JsonSerializationContext
-import com.google.gson.JsonSerializer
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.descriptors.PrimitiveKind
+import kotlinx.serialization.descriptors.PrimitiveSerialDescriptor
+import kotlinx.serialization.descriptors.SerialDescriptor
+import kotlinx.serialization.encoding.Decoder
+import kotlinx.serialization.encoding.Encoder
 import org.luxons.sevenwonders.model.resources.ResourceType
-import java.lang.reflect.Type
 
-internal class ResourceTypeSerializer : JsonSerializer<ResourceType>, JsonDeserializer<ResourceType> {
+internal object ResourceTypeSerializer : KSerializer<ResourceType> {
 
-    override fun serialize(type: ResourceType, typeOfSrc: Type, context: JsonSerializationContext): JsonElement =
-        JsonPrimitive(type.symbol)
+    override val descriptor: SerialDescriptor = PrimitiveSerialDescriptor("ResourceType", PrimitiveKind.STRING)
 
-    @Throws(JsonParseException::class)
-    override fun deserialize(json: JsonElement, typeOfT: Type, context: JsonDeserializationContext): ResourceType {
-        val str = json.asString
-        if (str.isEmpty()) {
-            throw IllegalArgumentException("Empty string is not a valid resource level")
-        }
-        return ResourceType.fromSymbol(str[0])
+    override fun serialize(encoder: Encoder, value: ResourceType) {
+        encoder.encodeString(value.symbol.toString())
     }
+
+    override fun deserialize(decoder: Decoder): ResourceType = ResourceType.fromSymbol(decoder.decodeString())
 }
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ResourceTypesSerializer.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ResourceTypesSerializer.kt
index ebbee8fd..8bd35f52 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ResourceTypesSerializer.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ResourceTypesSerializer.kt
@@ -1,30 +1,21 @@
 package org.luxons.sevenwonders.engine.data.serializers
 
-import com.google.gson.JsonDeserializationContext
-import com.google.gson.JsonDeserializer
-import com.google.gson.JsonElement
-import com.google.gson.JsonParseException
-import com.google.gson.JsonPrimitive
-import com.google.gson.JsonSerializationContext
-import com.google.gson.JsonSerializer
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.descriptors.PrimitiveKind
+import kotlinx.serialization.descriptors.PrimitiveSerialDescriptor
+import kotlinx.serialization.descriptors.SerialDescriptor
+import kotlinx.serialization.encoding.Decoder
+import kotlinx.serialization.encoding.Encoder
 import org.luxons.sevenwonders.model.resources.ResourceType
-import java.lang.reflect.Type
 
-internal class ResourceTypesSerializer : JsonSerializer<List<ResourceType>>, JsonDeserializer<List<ResourceType>> {
+internal object ResourceTypesSerializer : KSerializer<List<ResourceType>> {
 
-    override fun serialize(
-        resources: List<ResourceType>,
-        typeOfSrc: Type,
-        context: JsonSerializationContext,
-    ): JsonElement {
-        val s = resources.map { it.symbol }.joinToString("")
-        return JsonPrimitive(s)
+    override val descriptor: SerialDescriptor = PrimitiveSerialDescriptor("ResourceTypeList", PrimitiveKind.STRING)
+
+    override fun serialize(encoder: Encoder, value: List<ResourceType>) {
+        encoder.encodeString(value.map { it.symbol }.joinToString(""))
     }
 
-    @Throws(JsonParseException::class)
-    override fun deserialize(
-        json: JsonElement,
-        typeOfT: Type,
-        context: JsonDeserializationContext,
-    ): List<ResourceType> = json.asString.map { ResourceType.fromSymbol(it) }
+    override fun deserialize(decoder: Decoder): List<ResourceType> =
+        decoder.decodeString().map { ResourceType.fromSymbol(it) }
 }
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ResourcesSerializer.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ResourcesSerializer.kt
index 4226411d..cf31c380 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ResourcesSerializer.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ResourcesSerializer.kt
@@ -1,26 +1,27 @@
 package org.luxons.sevenwonders.engine.data.serializers
 
-import com.google.gson.JsonDeserializationContext
-import com.google.gson.JsonDeserializer
-import com.google.gson.JsonElement
-import com.google.gson.JsonNull
-import com.google.gson.JsonParseException
-import com.google.gson.JsonPrimitive
-import com.google.gson.JsonSerializationContext
-import com.google.gson.JsonSerializer
+import kotlinx.serialization.ExperimentalSerializationApi
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.descriptors.PrimitiveKind
+import kotlinx.serialization.descriptors.PrimitiveSerialDescriptor
+import kotlinx.serialization.descriptors.SerialDescriptor
+import kotlinx.serialization.encoding.Decoder
+import kotlinx.serialization.encoding.Encoder
 import org.luxons.sevenwonders.engine.resources.Resources
 import org.luxons.sevenwonders.engine.resources.toResources
 import org.luxons.sevenwonders.model.resources.ResourceType
-import java.lang.reflect.Type
 
-internal class ResourcesSerializer : JsonSerializer<Resources>, JsonDeserializer<Resources> {
+internal object ResourcesSerializer : KSerializer<Resources> {
 
-    override fun serialize(resources: Resources, typeOfSrc: Type, context: JsonSerializationContext): JsonElement {
-        val s = resources.toList().map { it.symbol }.joinToString("")
-        return if (s.isEmpty()) JsonNull.INSTANCE else JsonPrimitive(s)
+    override val descriptor: SerialDescriptor = PrimitiveSerialDescriptor("Resources", PrimitiveKind.STRING)
+
+    @OptIn(ExperimentalSerializationApi::class)
+    override fun serialize(encoder: Encoder, value: Resources) {
+        val s = value.toList().map { it.symbol }.joinToString("")
+        if (s.isEmpty()) encoder.encodeNull() else encoder.encodeString(s)
     }
 
-    @Throws(JsonParseException::class)
-    override fun deserialize(json: JsonElement, typeOfT: Type, context: JsonDeserializationContext): Resources =
-        json.asString.map { ResourceType.fromSymbol(it) to 1 }.toResources()
+    override fun deserialize(decoder: Decoder): Resources = deserializeString(decoder.decodeString())
+
+    fun deserializeString(symbols: String): Resources = symbols.map { ResourceType.fromSymbol(it) to 1 }.toResources()
 }
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ScienceProgressSerializer.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ScienceProgressSerializer.kt
index 1193c94b..b4493c70 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ScienceProgressSerializer.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/data/serializers/ScienceProgressSerializer.kt
@@ -1,55 +1,48 @@
 package org.luxons.sevenwonders.engine.data.serializers
 
-import com.google.gson.JsonDeserializationContext
-import com.google.gson.JsonDeserializer
-import com.google.gson.JsonElement
-import com.google.gson.JsonNull
-import com.google.gson.JsonParseException
-import com.google.gson.JsonPrimitive
-import com.google.gson.JsonSerializationContext
-import com.google.gson.JsonSerializer
+import kotlinx.serialization.ExperimentalSerializationApi
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.descriptors.PrimitiveKind
+import kotlinx.serialization.descriptors.PrimitiveSerialDescriptor
+import kotlinx.serialization.descriptors.SerialDescriptor
+import kotlinx.serialization.encoding.Decoder
+import kotlinx.serialization.encoding.Encoder
+import kotlinx.serialization.serializer
 import org.luxons.sevenwonders.engine.boards.Science
 import org.luxons.sevenwonders.engine.boards.ScienceType
 import org.luxons.sevenwonders.engine.effects.ScienceProgress
-import java.lang.reflect.Type
 
-internal class ScienceProgressSerializer : JsonSerializer<ScienceProgress>, JsonDeserializer<ScienceProgress> {
+internal object ScienceProgressSerializer : KSerializer<ScienceProgress> {
 
-    override fun serialize(
-        scienceProgress: ScienceProgress,
-        typeOfSrc: Type,
-        context: JsonSerializationContext,
-    ): JsonElement {
-        val science = scienceProgress.science
+    override val descriptor: SerialDescriptor = PrimitiveSerialDescriptor("ScienceProgress", PrimitiveKind.STRING)
 
-        if (science.size() > 1) {
+    @OptIn(ExperimentalSerializationApi::class)
+    override fun serialize(encoder: Encoder, value: ScienceProgress) {
+        if (value.science.size() > 1) {
             throw UnsupportedOperationException("Cannot serialize science containing more than one element")
         }
-
+        if (value.science.jokers == 1) {
+            encoder.encodeString("any")
+            return
+        }
         for (type in ScienceType.values()) {
-            val quantity = science.getQuantity(type)
+            val quantity = value.science.getQuantity(type)
             if (quantity == 1) {
-                return context.serialize(type)
+                encoder.encodeSerializableValue(serializer(), type)
+                return
             }
         }
-
-        return if (science.jokers == 1) JsonPrimitive("any") else JsonNull.INSTANCE
+        encoder.encodeNull()
     }
 
-    @Throws(JsonParseException::class)
-    override fun deserialize(json: JsonElement, typeOfT: Type, context: JsonDeserializationContext): ScienceProgress {
-        val s = json.asString
+    override fun deserialize(decoder: Decoder): ScienceProgress {
+        val s = decoder.decodeString()
         val science = Science()
         if ("any" == s) {
             science.addJoker(1)
         } else {
-            science.add(deserializeScienceType(json, context), 1)
+            science.add(ScienceType.valueOf(s), 1)
         }
         return ScienceProgress(science)
     }
-
-    private fun deserializeScienceType(json: JsonElement, context: JsonDeserializationContext): ScienceType {
-        return context.deserialize<ScienceType>(json, ScienceType::class.java)
-            ?: throw IllegalArgumentException("Invalid science level " + json.asString)
-    }
 }
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/BonusPerBoardElement.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/BonusPerBoardElement.kt
index 41dbd937..6f1cee51 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/BonusPerBoardElement.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/BonusPerBoardElement.kt
@@ -1,5 +1,6 @@
 package org.luxons.sevenwonders.engine.effects
 
+import kotlinx.serialization.Serializable
 import org.luxons.sevenwonders.engine.Player
 import org.luxons.sevenwonders.engine.boards.Board
 import org.luxons.sevenwonders.model.boards.RelativeBoardPosition
@@ -11,6 +12,7 @@ enum class BoardElementType {
     DEFEAT_TOKEN,
 }
 
+@Serializable
 internal data class BonusPerBoardElement(
     val boards: List<RelativeBoardPosition>,
     val type: BoardElementType,
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/Discount.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/Discount.kt
index 83a45e28..f74f79c8 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/Discount.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/Discount.kt
@@ -1,10 +1,14 @@
 package org.luxons.sevenwonders.engine.effects
 
+import kotlinx.serialization.Serializable
 import org.luxons.sevenwonders.engine.boards.Board
+import org.luxons.sevenwonders.engine.data.serializers.ResourceTypesSerializer
 import org.luxons.sevenwonders.model.resources.Provider
 import org.luxons.sevenwonders.model.resources.ResourceType
 
+@Serializable
 internal data class Discount(
+    @Serializable(with = ResourceTypesSerializer::class)
     val resourceTypes: List<ResourceType> = emptyList(),
     val providers: List<Provider> = emptyList(),
     val discountedPrice: Int = 1,
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/ProductionIncrease.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/ProductionIncrease.kt
index 6458ad20..006d7516 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/ProductionIncrease.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/ProductionIncrease.kt
@@ -1,14 +1,19 @@
 package org.luxons.sevenwonders.engine.effects
 
+import kotlinx.serialization.Serializable
 import org.luxons.sevenwonders.engine.boards.Board
 import org.luxons.sevenwonders.engine.resources.Production
 
-internal data class ProductionIncrease(val production: Production, val isSellable: Boolean) : InstantOwnBoardEffect() {
+@Serializable
+internal data class ProductionIncrease(
+    val resources: Production,
+    val isSellable: Boolean
+) : InstantOwnBoardEffect() {
 
     public override fun applyTo(board: Board) {
-        board.production.addAll(production)
+        board.production.addAll(resources)
         if (isSellable) {
-            board.publicProduction.addAll(production)
+            board.publicProduction.addAll(resources)
         }
     }
 }
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/ScienceProgress.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/ScienceProgress.kt
index 4ea8626f..50a670bb 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/ScienceProgress.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/effects/ScienceProgress.kt
@@ -1,8 +1,11 @@
 package org.luxons.sevenwonders.engine.effects
 
+import kotlinx.serialization.Serializable
 import org.luxons.sevenwonders.engine.boards.Board
 import org.luxons.sevenwonders.engine.boards.Science
+import org.luxons.sevenwonders.engine.data.serializers.ScienceProgressSerializer
 
+@Serializable(with = ScienceProgressSerializer::class)
 internal class ScienceProgress(val science: Science) : InstantOwnBoardEffect() {
 
     public override fun applyTo(board: Board) = board.science.addAll(science)
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/resources/Production.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/resources/Production.kt
index 3eb59bd5..ad11faab 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/resources/Production.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/resources/Production.kt
@@ -1,8 +1,11 @@
 package org.luxons.sevenwonders.engine.resources
 
+import kotlinx.serialization.Serializable
+import org.luxons.sevenwonders.engine.data.serializers.ProductionSerializer
 import org.luxons.sevenwonders.model.resources.ResourceType
 import java.util.EnumSet
 
+@Serializable(with = ProductionSerializer::class)
 data class Production internal constructor(
     private val fixedResources: MutableResources = mutableResourcesOf(),
     // cannot be a Set because the same choices can be there multiple times
diff --git a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/resources/Resources.kt b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/resources/Resources.kt
index b2dfc964..53556a3d 100644
--- a/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/resources/Resources.kt
+++ b/sw-engine/src/main/kotlin/org/luxons/sevenwonders/engine/resources/Resources.kt
@@ -1,5 +1,7 @@
 package org.luxons.sevenwonders.engine.resources
 
+import kotlinx.serialization.Serializable
+import org.luxons.sevenwonders.engine.data.serializers.ResourcesSerializer
 import org.luxons.sevenwonders.model.resources.ResourceType
 
 fun emptyResources(): Resources = MutableResources()
@@ -34,6 +36,7 @@ internal fun Map<ResourceType, Int>.toMutableResources(): MutableResources = Mut
 
 internal fun Resources.toMutableResources(): MutableResources = quantities.toMutableResources()
 
+@Serializable(with = ResourcesSerializer::class)
 interface Resources {
 
     val quantities: Map<ResourceType, Int>