From 6a08e16c23083b815e075410bb4d1a599da1be0d Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Sat, 19 Mar 2022 16:12:19 +0100
Subject: [PATCH 01/14] Done on Android

---
 .../kotlin/dev/gitlive/firebase/_decoders.kt  |  9 ++++---
 .../kotlin/dev/gitlive/firebase/_encoders.kt  | 24 +++++++++++--------
 2 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
index 2b31cece7..92357dda8 100644
--- a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -7,17 +7,20 @@ package dev.gitlive.firebase
 import kotlinx.serialization.encoding.CompositeDecoder
 import kotlinx.serialization.KSerializer
 import kotlinx.serialization.SerializationException
+import kotlinx.serialization.descriptors.PolymorphicKind
 import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
 
-actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decodeDouble: (value: Any?) -> Double?): CompositeDecoder = when(descriptor.kind as StructureKind) {
-        StructureKind.CLASS, StructureKind.OBJECT -> (value as Map<*, *>).let { map ->
+actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decodeDouble: (value: Any?) -> Double?): CompositeDecoder =
+    when(descriptor.kind) {
+        StructureKind.CLASS, StructureKind.OBJECT, PolymorphicKind.SEALED -> (value as Map<*, *>).let { map ->
             FirebaseClassDecoder(decodeDouble, map.size, { map.containsKey(it) }) { desc, index -> map[desc.getElementName(index)] }
         }
-        StructureKind.LIST -> (value as List<*>).let {
+        StructureKind.LIST, PolymorphicKind.SEALED-> (value as List<*>).let {
             FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index] }
         }
         StructureKind.MAP -> (value as Map<*, *>).entries.toList().let {
             FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index/2].run { if(index % 2 == 0) key else value }  }
         }
+        else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
     }
\ No newline at end of file
diff --git a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
index 84576846e..9ce7d8fbb 100644
--- a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
+++ b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
@@ -4,18 +4,22 @@
 
 package dev.gitlive.firebase
 
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.descriptors.PolymorphicKind
 import kotlinx.serialization.encoding.CompositeEncoder
 import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
 import kotlin.collections.set
 
-actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): CompositeEncoder = when(descriptor.kind as StructureKind) {
-    StructureKind.LIST -> mutableListOf<Any?>()
-        .also { value = it }
-        .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it.add(index, value) } }
-    StructureKind.MAP -> mutableListOf<Any?>()
-        .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity, { value = it.chunked(2).associate { (k, v) -> k to v } }) { _, _, value -> it.add(value) } }
-    StructureKind.CLASS,  StructureKind.OBJECT -> mutableMapOf<Any?, Any?>()
-        .also { value = it }
-        .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it[descriptor.getElementName(index)] = value } }
-}
\ No newline at end of file
+actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): CompositeEncoder =
+    when(descriptor.kind) {
+        StructureKind.LIST -> mutableListOf<Any?>()
+            .also { value = it }
+            .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it.add(index, value) } }
+        StructureKind.MAP -> mutableListOf<Any?>()
+            .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity, { value = it.chunked(2).associate { (k, v) -> k to v } }) { _, _, value -> it.add(value) } }
+        StructureKind.CLASS,  StructureKind.OBJECT, PolymorphicKind.SEALED -> mutableMapOf<Any?, Any?>()
+            .also { value = it }
+            .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it[descriptor.getElementName(index)] = value } }
+        else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
+    }
\ No newline at end of file

From 37bf8ca9705894d98fb7efebfa45376b57072119 Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Sun, 20 Mar 2022 17:41:52 +0100
Subject: [PATCH 02/14] Added on iOS and js

---
 .../src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt | 1 -
 .../src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt     | 5 +++--
 .../src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt     | 5 +++--
 .../src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt      | 3 ++-
 .../src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt      | 5 +++--
 5 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
index 9ce7d8fbb..e59feca82 100644
--- a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
+++ b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
@@ -4,7 +4,6 @@
 
 package dev.gitlive.firebase
 
-import kotlinx.serialization.KSerializer
 import kotlinx.serialization.descriptors.PolymorphicKind
 import kotlinx.serialization.encoding.CompositeEncoder
 import kotlinx.serialization.descriptors.SerialDescriptor
diff --git a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt
index 05ffad2cd..8da58a48f 100644
--- a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -7,11 +7,12 @@ package dev.gitlive.firebase
 import kotlinx.serialization.encoding.CompositeDecoder
 import kotlinx.serialization.KSerializer
 import kotlinx.serialization.SerializationException
+import kotlinx.serialization.descriptors.PolymorphicKind
 import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
 
-actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decodeDouble: (value: Any?) -> Double?): CompositeDecoder = when(descriptor.kind as StructureKind) {
-    StructureKind.CLASS, StructureKind.OBJECT -> (value as Map<*, *>).let { map ->
+actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decodeDouble: (value: Any?) -> Double?): CompositeDecoder = when(descriptor.kind) {
+    StructureKind.CLASS, StructureKind.OBJECT, PolymorphicKind.SEALED -> (value as Map<*, *>).let { map ->
         FirebaseClassDecoder(decodeDouble, map.size, { map.containsKey(it) }) { desc, index -> map[desc.getElementName(index)] }
     }
     StructureKind.LIST -> (value as List<*>).let {
diff --git a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt
index 84576846e..52e6c82dd 100644
--- a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt
+++ b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt
@@ -4,18 +4,19 @@
 
 package dev.gitlive.firebase
 
+import kotlinx.serialization.descriptors.PolymorphicKind
 import kotlinx.serialization.encoding.CompositeEncoder
 import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
 import kotlin.collections.set
 
-actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): CompositeEncoder = when(descriptor.kind as StructureKind) {
+actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): CompositeEncoder = when(descriptor.kind) {
     StructureKind.LIST -> mutableListOf<Any?>()
         .also { value = it }
         .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it.add(index, value) } }
     StructureKind.MAP -> mutableListOf<Any?>()
         .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity, { value = it.chunked(2).associate { (k, v) -> k to v } }) { _, _, value -> it.add(value) } }
-    StructureKind.CLASS,  StructureKind.OBJECT -> mutableMapOf<Any?, Any?>()
+    StructureKind.CLASS,  StructureKind.OBJECT, PolymorphicKind.SEALED -> mutableMapOf<Any?, Any?>()
         .also { value = it }
         .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it[descriptor.getElementName(index)] = value } }
 }
\ No newline at end of file
diff --git a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt
index 4e0d0b226..496f8670e 100644
--- a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -7,13 +7,14 @@ package dev.gitlive.firebase
 import kotlinx.serialization.encoding.CompositeDecoder
 import kotlinx.serialization.KSerializer
 import kotlinx.serialization.SerializationException
+import kotlinx.serialization.descriptors.PolymorphicKind
 import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
 import kotlin.js.Json
 
 @Suppress("UNCHECKED_CAST_TO_EXTERNAL_INTERFACE")
 actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decodeDouble: (value: Any?) -> Double?): CompositeDecoder = when(descriptor.kind as StructureKind) {
-    StructureKind.CLASS, StructureKind.OBJECT -> (value as Json).let { json ->
+    StructureKind.CLASS, StructureKind.OBJECT, PolymorphicKind.SEALED -> (value as Json).let { json ->
         FirebaseClassDecoder(decodeDouble, js("Object").keys(value).length as Int, { json[it] != undefined }) {
                 desc, index -> json[desc.getElementName(index)]
         }
diff --git a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt
index 5a7ce7a0f..cfa8e7ff0 100644
--- a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt
+++ b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt
@@ -4,12 +4,13 @@
 
 package dev.gitlive.firebase
 
+import kotlinx.serialization.descriptors.PolymorphicKind
 import kotlinx.serialization.encoding.CompositeEncoder
 import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
 import kotlin.js.json
 
-actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): CompositeEncoder = when(descriptor.kind as StructureKind) {
+actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): CompositeEncoder = when(descriptor.kind) {
     StructureKind.LIST -> Array<Any?>(descriptor.elementsCount) { null }
         .also { value = it }
         .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it[index] = value } }
@@ -19,7 +20,7 @@ actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): Compo
         value = map
         FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> if(index % 2 == 0) lastKey = value as String else map[lastKey] = value }
     }
-    StructureKind.CLASS,  StructureKind.OBJECT -> json()
+    StructureKind.CLASS,  StructureKind.OBJECT, PolymorphicKind.SEALED -> json()
         .also { value = it }
         .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it[descriptor.getElementName(index)] = value } }
 }

From 983702f4e629a13453097d9b914aec8b623c28e6 Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Sun, 20 Mar 2022 17:45:43 +0100
Subject: [PATCH 03/14] Add else branches

---
 .../src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt       | 1 +
 .../src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt       | 1 +
 .../src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt        | 3 ++-
 .../src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt        | 1 +
 4 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt
index 8da58a48f..949d9ce8f 100644
--- a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -21,4 +21,5 @@ actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decode
     StructureKind.MAP -> (value as Map<*, *>).entries.toList().let {
         FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index/2].run { if(index % 2 == 0) key else value }  }
     }
+    else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
 }
\ No newline at end of file
diff --git a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt
index 52e6c82dd..0070916c8 100644
--- a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt
+++ b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt
@@ -19,4 +19,5 @@ actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): Compo
     StructureKind.CLASS,  StructureKind.OBJECT, PolymorphicKind.SEALED -> mutableMapOf<Any?, Any?>()
         .also { value = it }
         .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it[descriptor.getElementName(index)] = value } }
+    else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
 }
\ No newline at end of file
diff --git a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt
index 496f8670e..484096833 100644
--- a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -13,7 +13,7 @@ import kotlinx.serialization.descriptors.StructureKind
 import kotlin.js.Json
 
 @Suppress("UNCHECKED_CAST_TO_EXTERNAL_INTERFACE")
-actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decodeDouble: (value: Any?) -> Double?): CompositeDecoder = when(descriptor.kind as StructureKind) {
+actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decodeDouble: (value: Any?) -> Double?): CompositeDecoder = when(descriptor.kind) {
     StructureKind.CLASS, StructureKind.OBJECT, PolymorphicKind.SEALED -> (value as Json).let { json ->
         FirebaseClassDecoder(decodeDouble, js("Object").keys(value).length as Int, { json[it] != undefined }) {
                 desc, index -> json[desc.getElementName(index)]
@@ -25,4 +25,5 @@ actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decode
     StructureKind.MAP -> (js("Object").entries(value) as Array<Array<Any>>).let {
         FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index/2].run { if(index % 2 == 0) get(0) else get(1) } }
     }
+    else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
 }
diff --git a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt
index cfa8e7ff0..a803e39c7 100644
--- a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt
+++ b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt
@@ -23,5 +23,6 @@ actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): Compo
     StructureKind.CLASS,  StructureKind.OBJECT, PolymorphicKind.SEALED -> json()
         .also { value = it }
         .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it[descriptor.getElementName(index)] = value } }
+    else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
 }
 

From 5d6edd56d8be20131e5b7a647cc2ce22c2650073 Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Sun, 20 Mar 2022 17:46:31 +0100
Subject: [PATCH 04/14] Keep format

---
 .../kotlin/dev/gitlive/firebase/_decoders.kt  | 25 +++++++++----------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
index 92357dda8..ea8656fef 100644
--- a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -11,16 +11,15 @@ import kotlinx.serialization.descriptors.PolymorphicKind
 import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
 
-actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decodeDouble: (value: Any?) -> Double?): CompositeDecoder =
-    when(descriptor.kind) {
-        StructureKind.CLASS, StructureKind.OBJECT, PolymorphicKind.SEALED -> (value as Map<*, *>).let { map ->
-            FirebaseClassDecoder(decodeDouble, map.size, { map.containsKey(it) }) { desc, index -> map[desc.getElementName(index)] }
-        }
-        StructureKind.LIST, PolymorphicKind.SEALED-> (value as List<*>).let {
-            FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index] }
-        }
-        StructureKind.MAP -> (value as Map<*, *>).entries.toList().let {
-            FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index/2].run { if(index % 2 == 0) key else value }  }
-        }
-        else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
-    }
\ No newline at end of file
+actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decodeDouble: (value: Any?) -> Double?): CompositeDecoder = when(descriptor.kind) {
+    StructureKind.CLASS, StructureKind.OBJECT, PolymorphicKind.SEALED -> (value as Map<*, *>).let { map ->
+        FirebaseClassDecoder(decodeDouble, map.size, { map.containsKey(it) }) { desc, index -> map[desc.getElementName(index)] }
+    }
+    StructureKind.LIST, PolymorphicKind.SEALED-> (value as List<*>).let {
+        FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index] }
+    }
+    StructureKind.MAP -> (value as Map<*, *>).entries.toList().let {
+        FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index/2].run { if(index % 2 == 0) key else value }  }
+    }
+    else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
+}
\ No newline at end of file

From de286d56b4cef57dc75fced3374b06346078b1fb Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Sun, 20 Mar 2022 17:47:58 +0100
Subject: [PATCH 05/14] Format

---
 .../kotlin/dev/gitlive/firebase/_decoders.kt  | 22 +++++++++----------
 .../kotlin/dev/gitlive/firebase/_encoders.kt  |  3 +--
 2 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
index ea8656fef..588cef0de 100644
--- a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -12,14 +12,14 @@ import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
 
 actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decodeDouble: (value: Any?) -> Double?): CompositeDecoder = when(descriptor.kind) {
-    StructureKind.CLASS, StructureKind.OBJECT, PolymorphicKind.SEALED -> (value as Map<*, *>).let { map ->
-        FirebaseClassDecoder(decodeDouble, map.size, { map.containsKey(it) }) { desc, index -> map[desc.getElementName(index)] }
-    }
-    StructureKind.LIST, PolymorphicKind.SEALED-> (value as List<*>).let {
-        FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index] }
-    }
-    StructureKind.MAP -> (value as Map<*, *>).entries.toList().let {
-        FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index/2].run { if(index % 2 == 0) key else value }  }
-    }
-    else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
-}
\ No newline at end of file
+        StructureKind.CLASS, StructureKind.OBJECT, PolymorphicKind.SEALED -> (value as Map<*, *>).let { map ->
+            FirebaseClassDecoder(decodeDouble, map.size, { map.containsKey(it) }) { desc, index -> map[desc.getElementName(index)] }
+        }
+        StructureKind.LIST, PolymorphicKind.SEALED-> (value as List<*>).let {
+            FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index] }
+        }
+        StructureKind.MAP -> (value as Map<*, *>).entries.toList().let {
+            FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index/2].run { if(index % 2 == 0) key else value }  }
+        }
+        else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
+    }
\ No newline at end of file
diff --git a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
index e59feca82..5761b5a13 100644
--- a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
+++ b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
@@ -10,8 +10,7 @@ import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
 import kotlin.collections.set
 
-actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): CompositeEncoder =
-    when(descriptor.kind) {
+actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): CompositeEncoder = when(descriptor.kind) {
         StructureKind.LIST -> mutableListOf<Any?>()
             .also { value = it }
             .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it.add(index, value) } }

From 5e88cc275612fbb7724d5b84eb9689f5d0207656 Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Sun, 20 Mar 2022 17:49:10 +0100
Subject: [PATCH 06/14] Format

---
 .../kotlin/dev/gitlive/firebase/_decoders.kt  |  2 +-
 .../kotlin/dev/gitlive/firebase/_encoders.kt  | 20 +++++++++----------
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
index 588cef0de..d8d2643b4 100644
--- a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -15,7 +15,7 @@ actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decode
         StructureKind.CLASS, StructureKind.OBJECT, PolymorphicKind.SEALED -> (value as Map<*, *>).let { map ->
             FirebaseClassDecoder(decodeDouble, map.size, { map.containsKey(it) }) { desc, index -> map[desc.getElementName(index)] }
         }
-        StructureKind.LIST, PolymorphicKind.SEALED-> (value as List<*>).let {
+        StructureKind.LIST -> (value as List<*>).let {
             FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index] }
         }
         StructureKind.MAP -> (value as Map<*, *>).entries.toList().let {
diff --git a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
index 5761b5a13..0070916c8 100644
--- a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
+++ b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
@@ -11,13 +11,13 @@ import kotlinx.serialization.descriptors.StructureKind
 import kotlin.collections.set
 
 actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): CompositeEncoder = when(descriptor.kind) {
-        StructureKind.LIST -> mutableListOf<Any?>()
-            .also { value = it }
-            .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it.add(index, value) } }
-        StructureKind.MAP -> mutableListOf<Any?>()
-            .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity, { value = it.chunked(2).associate { (k, v) -> k to v } }) { _, _, value -> it.add(value) } }
-        StructureKind.CLASS,  StructureKind.OBJECT, PolymorphicKind.SEALED -> mutableMapOf<Any?, Any?>()
-            .also { value = it }
-            .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it[descriptor.getElementName(index)] = value } }
-        else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
-    }
\ No newline at end of file
+    StructureKind.LIST -> mutableListOf<Any?>()
+        .also { value = it }
+        .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it.add(index, value) } }
+    StructureKind.MAP -> mutableListOf<Any?>()
+        .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity, { value = it.chunked(2).associate { (k, v) -> k to v } }) { _, _, value -> it.add(value) } }
+    StructureKind.CLASS,  StructureKind.OBJECT, PolymorphicKind.SEALED -> mutableMapOf<Any?, Any?>()
+        .also { value = it }
+        .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it[descriptor.getElementName(index)] = value } }
+    else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
+}
\ No newline at end of file

From 2bb2f07057d550a44333fe74fe887b7d721db1ff Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Mon, 21 Mar 2022 13:27:32 +0100
Subject: [PATCH 07/14] Add testing

---
 .../kotlin/dev/gitlive/firebase/_decoders.kt  |  2 --
 .../dev/gitlive/firebase/EncodersTest.kt      | 21 +++++++++++++++++++
 .../kotlin/dev/gitlive/firebase/_decoders.kt  |  2 --
 .../kotlin/dev/gitlive/firebase/_decoders.kt  |  2 --
 4 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
index d8d2643b4..cabb99e49 100644
--- a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -5,8 +5,6 @@
 package dev.gitlive.firebase
 
 import kotlinx.serialization.encoding.CompositeDecoder
-import kotlinx.serialization.KSerializer
-import kotlinx.serialization.SerializationException
 import kotlinx.serialization.descriptors.PolymorphicKind
 import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
diff --git a/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt b/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt
index 2d5741835..09baee17a 100644
--- a/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt
+++ b/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt
@@ -4,6 +4,7 @@
 
 package dev.gitlive.firebase
 
+import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.builtins.ListSerializer
 import kotlin.test.Test
@@ -17,6 +18,13 @@ expect fun nativeAssertEquals(expected: Any?, actual: Any?): Unit
 @Serializable
 data class TestData(val map: Map<String, String>, val bool: Boolean = false, val nullableBool: Boolean? = null)
 
+@Serializable
+sealed class TestSealed {
+    @Serializable
+    @SerialName("child")
+    data class ChildClass(val map: Map<String, String>, val bool: Boolean = false): TestSealed()
+}
+
 class EncodersTest {
     @Test
     fun encodeMap() {
@@ -37,6 +45,13 @@ class EncodersTest {
         nativeAssertEquals(nativeMapOf("map" to nativeMapOf("key" to "value"), "bool" to true, "nullableBool" to true), encoded)
     }
 
+    @Test
+    fun encodeSealedClass() {
+        val encoded = encode<TestSealed>(TestSealed.serializer(), TestSealed.ChildClass(mapOf("key" to "value"), true), shouldEncodeElementDefault = true)
+        println(encoded.toString())
+        nativeAssertEquals(nativeMapOf("type" to "child", "value" to nativeMapOf("map" to nativeMapOf("key" to "value"), "bool" to true)), encoded)
+    }
+
     @Test
     fun decodeObject() {
         val decoded = decode<TestData>(TestData.serializer(), nativeMapOf("map" to nativeMapOf("key" to "value")))
@@ -54,4 +69,10 @@ class EncodersTest {
         val decoded = decode(TestData.serializer(), nativeMapOf("map" to mapOf("key" to "value"), "nullableBool" to null))
         assertNull(decoded.nullableBool)
     }
+
+    @Test
+    fun decodeSealedClass() {
+        val decoded = decode(TestSealed.serializer(), nativeMapOf("type" to "child", "value" to nativeMapOf("map" to nativeMapOf("key" to "value"), "bool" to true)))
+        assertEquals(TestSealed.ChildClass(mapOf("key" to "value"), true), decoded)
+    }
 }
\ No newline at end of file
diff --git a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt
index 949d9ce8f..9d3ca29c5 100644
--- a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -5,8 +5,6 @@
 package dev.gitlive.firebase
 
 import kotlinx.serialization.encoding.CompositeDecoder
-import kotlinx.serialization.KSerializer
-import kotlinx.serialization.SerializationException
 import kotlinx.serialization.descriptors.PolymorphicKind
 import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
diff --git a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt
index 484096833..166aef84e 100644
--- a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -5,8 +5,6 @@
 package dev.gitlive.firebase
 
 import kotlinx.serialization.encoding.CompositeDecoder
-import kotlinx.serialization.KSerializer
-import kotlinx.serialization.SerializationException
 import kotlinx.serialization.descriptors.PolymorphicKind
 import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind

From 6f690662e0820b44da0d6fbbe664d60731571b80 Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Mon, 21 Mar 2022 16:14:29 +0100
Subject: [PATCH 08/14] Remove logging

---
 .../src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt   | 1 -
 1 file changed, 1 deletion(-)

diff --git a/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt b/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt
index 09baee17a..944cc6d26 100644
--- a/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt
+++ b/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt
@@ -48,7 +48,6 @@ class EncodersTest {
     @Test
     fun encodeSealedClass() {
         val encoded = encode<TestSealed>(TestSealed.serializer(), TestSealed.ChildClass(mapOf("key" to "value"), true), shouldEncodeElementDefault = true)
-        println(encoded.toString())
         nativeAssertEquals(nativeMapOf("type" to "child", "value" to nativeMapOf("map" to nativeMapOf("key" to "value"), "bool" to true)), encoded)
     }
 

From 7a6d8154820bee29cb7b70550d2dca988a945adb Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Thu, 24 Mar 2022 14:30:23 +0100
Subject: [PATCH 09/14] Add polymorphic serialization

---
 .../kotlin/dev/gitlive/firebase/_decoders.kt  |  5 +-
 .../kotlin/dev/gitlive/firebase/_encoders.kt  | 13 +--
 .../firebase/FirebaseClassDiscriminator.kt    |  7 ++
 .../dev/gitlive/firebase/Polymorphic.kt       | 87 +++++++++++++++++++
 .../kotlin/dev/gitlive/firebase/decoders.kt   | 10 ++-
 .../kotlin/dev/gitlive/firebase/encoders.kt   | 28 ++++--
 .../dev/gitlive/firebase/EncodersTest.kt      |  5 +-
 .../kotlin/dev/gitlive/firebase/_decoders.kt  |  5 +-
 .../kotlin/dev/gitlive/firebase/_encoders.kt  |  9 +-
 .../kotlin/dev/gitlive/firebase/_decoders.kt  |  4 +
 .../kotlin/dev/gitlive/firebase/_encoders.kt  | 11 ++-
 11 files changed, 163 insertions(+), 21 deletions(-)
 create mode 100644 firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/FirebaseClassDiscriminator.kt
 create mode 100644 firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/Polymorphic.kt

diff --git a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
index cabb99e49..4516eabbe 100644
--- a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -20,4 +20,7 @@ actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decode
             FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index/2].run { if(index % 2 == 0) key else value }  }
         }
         else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
-    }
\ No newline at end of file
+    }
+
+actual fun getPolymorphicType(value: Any?, discriminator: String): String =
+    (value as Map<*,*>)[discriminator] as String
\ No newline at end of file
diff --git a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
index 0070916c8..928936d38 100644
--- a/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
+++ b/firebase-common/src/androidMain/kotlin/dev/gitlive/firebase/_encoders.kt
@@ -4,20 +4,23 @@
 
 package dev.gitlive.firebase
 
-import kotlinx.serialization.descriptors.PolymorphicKind
-import kotlinx.serialization.encoding.CompositeEncoder
 import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
 import kotlin.collections.set
 
-actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): CompositeEncoder = when(descriptor.kind) {
+actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): FirebaseCompositeEncoder = when(descriptor.kind) {
     StructureKind.LIST -> mutableListOf<Any?>()
         .also { value = it }
         .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it.add(index, value) } }
     StructureKind.MAP -> mutableListOf<Any?>()
         .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity, { value = it.chunked(2).associate { (k, v) -> k to v } }) { _, _, value -> it.add(value) } }
-    StructureKind.CLASS,  StructureKind.OBJECT, PolymorphicKind.SEALED -> mutableMapOf<Any?, Any?>()
+    StructureKind.CLASS,  StructureKind.OBJECT -> mutableMapOf<Any?, Any?>()
         .also { value = it }
-        .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it[descriptor.getElementName(index)] = value } }
+        .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity,
+            setPolymorphicType = { discriminator, type ->
+                it[discriminator] = type
+            },
+            set = { _, index, value -> it[descriptor.getElementName(index)] = value }
+        ) }
     else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
 }
\ No newline at end of file
diff --git a/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/FirebaseClassDiscriminator.kt b/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/FirebaseClassDiscriminator.kt
new file mode 100644
index 000000000..2ed4bafa1
--- /dev/null
+++ b/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/FirebaseClassDiscriminator.kt
@@ -0,0 +1,7 @@
+package dev.gitlive.firebase
+
+import kotlinx.serialization.InheritableSerialInfo
+
+@InheritableSerialInfo
+@Target(AnnotationTarget.CLASS)
+annotation class FirebaseClassDiscriminator(val discriminator: String)
\ No newline at end of file
diff --git a/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/Polymorphic.kt b/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/Polymorphic.kt
new file mode 100644
index 000000000..e6955ddb4
--- /dev/null
+++ b/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/Polymorphic.kt
@@ -0,0 +1,87 @@
+package dev.gitlive.firebase
+
+import kotlinx.serialization.DeserializationStrategy
+import kotlinx.serialization.SerializationStrategy
+import kotlinx.serialization.descriptors.SerialDescriptor
+import kotlinx.serialization.encoding.CompositeDecoder
+import kotlinx.serialization.findPolymorphicSerializer
+import kotlinx.serialization.internal.AbstractPolymorphicSerializer
+
+
+@Suppress("UNCHECKED_CAST")
+internal fun <T> FirebaseEncoder.encodePolymorphically(
+    serializer: SerializationStrategy<T>,
+    value: T,
+    ifPolymorphic: (String) -> Unit
+) {
+    if (serializer !is AbstractPolymorphicSerializer<*>) {
+        serializer.serialize(this, value)
+        return
+    }
+    val casted = serializer as AbstractPolymorphicSerializer<Any>
+    val baseClassDiscriminator = serializer.descriptor.classDiscriminator()
+    val actualSerializer = casted.findPolymorphicSerializer(this, value as Any)
+//    validateIfSealed(casted, actualSerializer, baseClassDiscriminator)
+//    checkKind(actualSerializer.descriptor.kind)
+    ifPolymorphic(baseClassDiscriminator)
+    actualSerializer.serialize(this, value)
+}
+
+
+
+@Suppress("UNCHECKED_CAST")
+internal fun <T> FirebaseDecoder.decodeSerializableValuePolymorphic(
+    value: Any?,
+    decodeDouble: (value: Any?) -> Double?,
+    deserializer: DeserializationStrategy<T>,
+): T {
+    if (deserializer !is AbstractPolymorphicSerializer<*>) {
+        return deserializer.deserialize(this)
+    }
+
+    val casted = deserializer as AbstractPolymorphicSerializer<Any>
+    val discriminator = deserializer.descriptor.classDiscriminator()
+    val type = getPolymorphicType(value, discriminator)
+    val actualDeserializer = casted.findPolymorphicSerializerOrNull(
+        structureDecoder(deserializer.descriptor, decodeDouble),
+        type
+    ) as DeserializationStrategy<T>
+    return actualDeserializer.deserialize(this)
+}
+
+
+//private fun validateIfSealed(
+//    serializer: SerializationStrategy<*>,
+//    actualSerializer: SerializationStrategy<Any>,
+//    classDiscriminator: String
+//) {
+//    if (serializer !is SealedClassSerializer<*>) return
+//    @Suppress("DEPRECATION_ERROR")
+//    if (classDiscriminator in actualSerializer.descriptor.jsonCachedSerialNames()) {
+//        val baseName = serializer.descriptor.serialName
+//        val actualName = actualSerializer.descriptor.serialName
+//        error(
+//            "Sealed class '$actualName' cannot be serialized as base class '$baseName' because" +
+//                    " it has property name that conflicts with class discriminator '$classDiscriminator'. " +
+//                    "You can either change class discriminator with FirebaseClassDiscriminator annotation or " +
+//                    "rename property with @SerialName annotation"
+//        )
+//    }
+//}
+
+//internal fun checkKind(kind: SerialKind) {
+//    if (kind is SerialKind.ENUM) error("Enums cannot be serialized polymorphically with 'type' parameter. You can use 'JsonBuilder.useArrayPolymorphism' instead")
+//    if (kind is PrimitiveKind) error("Primitives cannot be serialized polymorphically with 'type' parameter. You can use 'JsonBuilder.useArrayPolymorphism' instead")
+//    if (kind is PolymorphicKind) error("Actual serializer for polymorphic cannot be polymorphic itself")
+//}
+
+internal fun SerialDescriptor.classDiscriminator(): String {
+    // Plain loop is faster than allocation of Sequence or ArrayList
+    // We can rely on the fact that only one FirebaseClassDiscriminator is present —
+    // compiler plugin checked that.
+    for (annotation in annotations) {
+        if (annotation is FirebaseClassDiscriminator) return annotation.discriminator
+    }
+    return "type"
+}
+
diff --git a/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/decoders.kt b/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/decoders.kt
index c771d63e1..6be266b56 100644
--- a/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/decoders.kt
+++ b/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/decoders.kt
@@ -25,8 +25,8 @@ fun <T> decode(strategy: DeserializationStrategy<T>, value: Any?, decodeDouble:
     require(value != null || strategy.descriptor.isNullable) { "Value was null for non-nullable type ${strategy.descriptor.serialName}" }
     return FirebaseDecoder(value, decodeDouble).decodeSerializableValue(strategy)
 }
-
 expect fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decodeDouble: (value: Any?) -> Double?): CompositeDecoder
+expect fun getPolymorphicType(value: Any?, discriminator: String): String
 
 class FirebaseDecoder(internal val value: Any?, private val decodeDouble: (value: Any?) -> Double?) : Decoder {
 
@@ -59,8 +59,11 @@ class FirebaseDecoder(internal val value: Any?, private val decodeDouble: (value
 
     override fun decodeNull() = decodeNull(value)
 
-    @ExperimentalSerializationApi
     override fun decodeInline(inlineDescriptor: SerialDescriptor) = FirebaseDecoder(value, decodeDouble)
+
+    override fun <T> decodeSerializableValue(deserializer: DeserializationStrategy<T>): T {
+        return decodeSerializableValuePolymorphic(value, decodeDouble, deserializer)
+    }
 }
 
 class FirebaseClassDecoder(
@@ -80,7 +83,7 @@ class FirebaseClassDecoder(
             ?: DECODE_DONE
 }
 
-open class FirebaseCompositeDecoder constructor(
+open class FirebaseCompositeDecoder(
     private val decodeDouble: (value: Any?) -> Double?,
     private val size: Int,
     private val get: (descriptor: SerialDescriptor, index: Int) -> Any?
@@ -134,6 +137,7 @@ open class FirebaseCompositeDecoder constructor(
     @ExperimentalSerializationApi
     override fun decodeInlineElement(descriptor: SerialDescriptor, index: Int): Decoder =
         FirebaseDecoder(get(descriptor, index), decodeDouble)
+
 }
 
 private fun decodeString(value: Any?) = value.toString()
diff --git a/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/encoders.kt b/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/encoders.kt
index afb637492..7afe032bc 100644
--- a/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/encoders.kt
+++ b/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/encoders.kt
@@ -16,14 +16,23 @@ inline fun <reified T> encode(value: T, shouldEncodeElementDefault: Boolean, pos
     FirebaseEncoder(shouldEncodeElementDefault, positiveInfinity).apply { encodeSerializableValue(it.firebaseSerializer(), it) }.value
 }
 
-expect fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): CompositeEncoder
+expect fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): FirebaseCompositeEncoder
 
 class FirebaseEncoder(internal val shouldEncodeElementDefault: Boolean, positiveInfinity: Any) : TimestampEncoder(positiveInfinity), Encoder {
 
     var value: Any? = null
 
     override val serializersModule = EmptySerializersModule
-    override fun beginStructure(descriptor: SerialDescriptor) = structureEncoder(descriptor)
+    private var polymorphicDiscriminator: String? = null
+
+    override fun beginStructure(descriptor: SerialDescriptor): CompositeEncoder {
+        val encoder = structureEncoder(descriptor)
+        if (polymorphicDiscriminator != null) {
+            encoder.encodePolymorphicClassDiscriminator(polymorphicDiscriminator!!, descriptor.serialName)
+            polymorphicDiscriminator = null
+        }
+        return encoder
+    }
 
     override fun encodeBoolean(value: Boolean) {
         this.value = value
@@ -73,9 +82,14 @@ class FirebaseEncoder(internal val shouldEncodeElementDefault: Boolean, positive
         this.value = value
     }
 
-    @ExperimentalSerializationApi
     override fun encodeInline(inlineDescriptor: SerialDescriptor): Encoder =
         FirebaseEncoder(shouldEncodeElementDefault, positiveInfinity)
+
+    override fun <T> encodeSerializableValue(serializer: SerializationStrategy<T>, value: T) {
+        encodePolymorphically(serializer, value) {
+            polymorphicDiscriminator = it
+        }
+    }
 }
 
 abstract class TimestampEncoder(internal val positiveInfinity: Any) {
@@ -89,7 +103,8 @@ open class FirebaseCompositeEncoder constructor(
     private val shouldEncodeElementDefault: Boolean,
     positiveInfinity: Any,
     private val end: () -> Unit = {},
-    private val set: (descriptor: SerialDescriptor, index: Int, value: Any?) -> Unit
+    private val setPolymorphicType: (String, String) -> Unit = { _, _ -> },
+    private val set: (descriptor: SerialDescriptor, index: Int, value: Any?) -> Unit,
 ): TimestampEncoder(positiveInfinity), CompositeEncoder {
 
     override val serializersModule = EmptySerializersModule
@@ -153,6 +168,9 @@ open class FirebaseCompositeEncoder constructor(
     @ExperimentalSerializationApi
     override fun encodeInlineElement(descriptor: SerialDescriptor, index: Int): Encoder =
         FirebaseEncoder(shouldEncodeElementDefault, positiveInfinity)
-}
 
+    fun encodePolymorphicClassDiscriminator(discriminator: String, type: String) {
+        setPolymorphicType(discriminator, type)
+    }
+}
 
diff --git a/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt b/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt
index 944cc6d26..924564fb5 100644
--- a/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt
+++ b/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt
@@ -7,6 +7,7 @@ package dev.gitlive.firebase
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.builtins.ListSerializer
+import kotlinx.serialization.json.JsonClassDiscriminator
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertNull
@@ -48,7 +49,7 @@ class EncodersTest {
     @Test
     fun encodeSealedClass() {
         val encoded = encode<TestSealed>(TestSealed.serializer(), TestSealed.ChildClass(mapOf("key" to "value"), true), shouldEncodeElementDefault = true)
-        nativeAssertEquals(nativeMapOf("type" to "child", "value" to nativeMapOf("map" to nativeMapOf("key" to "value"), "bool" to true)), encoded)
+        nativeAssertEquals(nativeMapOf("type" to "child", "map" to nativeMapOf("key" to "value"), "bool" to true), encoded)
     }
 
     @Test
@@ -71,7 +72,7 @@ class EncodersTest {
 
     @Test
     fun decodeSealedClass() {
-        val decoded = decode(TestSealed.serializer(), nativeMapOf("type" to "child", "value" to nativeMapOf("map" to nativeMapOf("key" to "value"), "bool" to true)))
+        val decoded = decode(TestSealed.serializer(), nativeMapOf("type" to "child", "map" to nativeMapOf("key" to "value"), "bool" to true))
         assertEquals(TestSealed.ChildClass(mapOf("key" to "value"), true), decoded)
     }
 }
\ No newline at end of file
diff --git a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt
index 9d3ca29c5..5e87c2f9a 100644
--- a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -20,4 +20,7 @@ actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decode
         FirebaseCompositeDecoder(decodeDouble, it.size) { _, index -> it[index/2].run { if(index % 2 == 0) key else value }  }
     }
     else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
-}
\ No newline at end of file
+}
+
+actual fun getPolymorphicType(value: Any?, discriminator: String): String =
+    (value as Map<*,*>)[discriminator] as String
\ No newline at end of file
diff --git a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt
index 0070916c8..e887f1957 100644
--- a/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt
+++ b/firebase-common/src/iosMain/kotlin/dev/gitlive/firebase/_encoders.kt
@@ -10,7 +10,7 @@ import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
 import kotlin.collections.set
 
-actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): CompositeEncoder = when(descriptor.kind) {
+actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): FirebaseCompositeEncoder = when(descriptor.kind) {
     StructureKind.LIST -> mutableListOf<Any?>()
         .also { value = it }
         .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it.add(index, value) } }
@@ -18,6 +18,11 @@ actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): Compo
         .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity, { value = it.chunked(2).associate { (k, v) -> k to v } }) { _, _, value -> it.add(value) } }
     StructureKind.CLASS,  StructureKind.OBJECT, PolymorphicKind.SEALED -> mutableMapOf<Any?, Any?>()
         .also { value = it }
-        .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it[descriptor.getElementName(index)] = value } }
+        .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity,
+            setPolymorphicType = { discriminator, type ->
+                it[discriminator] = type
+            },
+            set = { _, index, value -> it[descriptor.getElementName(index)] = value }
+        ) }
     else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
 }
\ No newline at end of file
diff --git a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt
index 166aef84e..af200fc69 100644
--- a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt
+++ b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_decoders.kt
@@ -25,3 +25,7 @@ actual fun FirebaseDecoder.structureDecoder(descriptor: SerialDescriptor, decode
     }
     else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
 }
+
+@Suppress("UNCHECKED_CAST_TO_EXTERNAL_INTERFACE")
+actual fun getPolymorphicType(value: Any?, discriminator: String): String =
+    (value as Json)[discriminator] as String
diff --git a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt
index a803e39c7..b5f5aeaef 100644
--- a/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt
+++ b/firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/_encoders.kt
@@ -10,7 +10,7 @@ import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.descriptors.StructureKind
 import kotlin.js.json
 
-actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): CompositeEncoder = when(descriptor.kind) {
+actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): FirebaseCompositeEncoder = when(descriptor.kind) {
     StructureKind.LIST -> Array<Any?>(descriptor.elementsCount) { null }
         .also { value = it }
         .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it[index] = value } }
@@ -22,7 +22,14 @@ actual fun FirebaseEncoder.structureEncoder(descriptor: SerialDescriptor): Compo
     }
     StructureKind.CLASS,  StructureKind.OBJECT, PolymorphicKind.SEALED -> json()
         .also { value = it }
-        .let { FirebaseCompositeEncoder(shouldEncodeElementDefault, positiveInfinity) { _, index, value -> it[descriptor.getElementName(index)] = value } }
+        .let { FirebaseCompositeEncoder(
+            shouldEncodeElementDefault,
+            positiveInfinity,
+            setPolymorphicType = { discriminator, type ->
+                it[discriminator] = type
+            },
+            set = { _, index, value -> it[descriptor.getElementName(index)] = value }
+        ) }
     else -> TODO("The firebase-kotlin-sdk does not support $descriptor for serialization yet")
 }
 

From 477a10eff7b79af4a7b2e18dbfe169ab49365d85 Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Thu, 24 Mar 2022 14:52:43 +0100
Subject: [PATCH 10/14] Cleanup

---
 .../dev/gitlive/firebase/Polymorphic.kt       | 32 -------------------
 .../dev/gitlive/firebase/EncodersTest.kt      |  1 -
 2 files changed, 33 deletions(-)

diff --git a/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/Polymorphic.kt b/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/Polymorphic.kt
index e6955ddb4..ace429795 100644
--- a/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/Polymorphic.kt
+++ b/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/Polymorphic.kt
@@ -3,11 +3,9 @@ package dev.gitlive.firebase
 import kotlinx.serialization.DeserializationStrategy
 import kotlinx.serialization.SerializationStrategy
 import kotlinx.serialization.descriptors.SerialDescriptor
-import kotlinx.serialization.encoding.CompositeDecoder
 import kotlinx.serialization.findPolymorphicSerializer
 import kotlinx.serialization.internal.AbstractPolymorphicSerializer
 
-
 @Suppress("UNCHECKED_CAST")
 internal fun <T> FirebaseEncoder.encodePolymorphically(
     serializer: SerializationStrategy<T>,
@@ -21,14 +19,10 @@ internal fun <T> FirebaseEncoder.encodePolymorphically(
     val casted = serializer as AbstractPolymorphicSerializer<Any>
     val baseClassDiscriminator = serializer.descriptor.classDiscriminator()
     val actualSerializer = casted.findPolymorphicSerializer(this, value as Any)
-//    validateIfSealed(casted, actualSerializer, baseClassDiscriminator)
-//    checkKind(actualSerializer.descriptor.kind)
     ifPolymorphic(baseClassDiscriminator)
     actualSerializer.serialize(this, value)
 }
 
-
-
 @Suppress("UNCHECKED_CAST")
 internal fun <T> FirebaseDecoder.decodeSerializableValuePolymorphic(
     value: Any?,
@@ -49,32 +43,6 @@ internal fun <T> FirebaseDecoder.decodeSerializableValuePolymorphic(
     return actualDeserializer.deserialize(this)
 }
 
-
-//private fun validateIfSealed(
-//    serializer: SerializationStrategy<*>,
-//    actualSerializer: SerializationStrategy<Any>,
-//    classDiscriminator: String
-//) {
-//    if (serializer !is SealedClassSerializer<*>) return
-//    @Suppress("DEPRECATION_ERROR")
-//    if (classDiscriminator in actualSerializer.descriptor.jsonCachedSerialNames()) {
-//        val baseName = serializer.descriptor.serialName
-//        val actualName = actualSerializer.descriptor.serialName
-//        error(
-//            "Sealed class '$actualName' cannot be serialized as base class '$baseName' because" +
-//                    " it has property name that conflicts with class discriminator '$classDiscriminator'. " +
-//                    "You can either change class discriminator with FirebaseClassDiscriminator annotation or " +
-//                    "rename property with @SerialName annotation"
-//        )
-//    }
-//}
-
-//internal fun checkKind(kind: SerialKind) {
-//    if (kind is SerialKind.ENUM) error("Enums cannot be serialized polymorphically with 'type' parameter. You can use 'JsonBuilder.useArrayPolymorphism' instead")
-//    if (kind is PrimitiveKind) error("Primitives cannot be serialized polymorphically with 'type' parameter. You can use 'JsonBuilder.useArrayPolymorphism' instead")
-//    if (kind is PolymorphicKind) error("Actual serializer for polymorphic cannot be polymorphic itself")
-//}
-
 internal fun SerialDescriptor.classDiscriminator(): String {
     // Plain loop is faster than allocation of Sequence or ArrayList
     // We can rely on the fact that only one FirebaseClassDiscriminator is present —
diff --git a/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt b/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt
index 924564fb5..d61c1e5d1 100644
--- a/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt
+++ b/firebase-common/src/commonTest/kotlin/dev/gitlive/firebase/EncodersTest.kt
@@ -7,7 +7,6 @@ package dev.gitlive.firebase
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.builtins.ListSerializer
-import kotlinx.serialization.json.JsonClassDiscriminator
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertNull

From ae01585d2c21ec08ee8eee6b0f96613cbac4ca8e Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Thu, 24 Mar 2022 19:43:10 +0100
Subject: [PATCH 11/14] Add polymorphic serialization section to Readme

---
 README.md | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/README.md b/README.md
index 26101e39d..802f01b0c 100644
--- a/README.md
+++ b/README.md
@@ -102,6 +102,12 @@ data class Post(
 
 ```
 
+<h4>Polymorphic serialization (sealed classes)</h4>
+
+This sdk will handle polymorphic serialization automatically if you have a sealed class and its children marked as `Serializable`. It will include a `type` property that will be used to discriminate which child class is the serialized.
+
+You can change this `type` property by using the `@FirebaseClassDiscrminator` annotation in the parent sealed class.
+
 <h3><a href="https://kotlinlang.org/docs/reference/functions.html#default-arguments">Default arguments</a></h3>
 
 To reduce boilerplate, default arguments are used in the places where the Firebase Android SDK employs the builder pattern:

From 2516bebd78ffb305b3aaa9c42b52acbecca548e4 Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Fri, 25 Mar 2022 22:49:44 +0100
Subject: [PATCH 12/14] Add sample of @FirebaseClassDiscriminator usage

---
 README.md | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 802f01b0c..b5b2a490b 100644
--- a/README.md
+++ b/README.md
@@ -106,7 +106,28 @@ data class Post(
 
 This sdk will handle polymorphic serialization automatically if you have a sealed class and its children marked as `Serializable`. It will include a `type` property that will be used to discriminate which child class is the serialized.
 
-You can change this `type` property by using the `@FirebaseClassDiscrminator` annotation in the parent sealed class.
+You can change this `type` property by using the `@FirebaseClassDiscrminator` annotation in the parent sealed class:
+
+```kotlin
+@Serializable
+@FirebaseClassDiscriminator("class")
+sealed class Parent {
+    @Serializable
+    @SerialName("child")
+    data class Child(
+        val property: Boolean
+    ) : Parent
+}
+```
+
+In combination with a `SerialName` specified for the child class, you have full control over the serialized data. In this case it will be:
+
+```json
+{
+  class: "child",
+  property: true
+}
+```
 
 <h3><a href="https://kotlinlang.org/docs/reference/functions.html#default-arguments">Default arguments</a></h3>
 

From a2f6b6854d14543f703dfdf459c647d0c410c4c7 Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Fri, 25 Mar 2022 22:50:57 +0100
Subject: [PATCH 13/14] Fix sample

---
 README.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index b5b2a490b..084fbb39d 100644
--- a/README.md
+++ b/README.md
@@ -124,8 +124,8 @@ In combination with a `SerialName` specified for the child class, you have full
 
 ```json
 {
-  class: "child",
-  property: true
+  "class": "child",
+  "property": true
 }
 ```
 

From a9a20519a587d9a473ad3a1bb9905d04d9013c98 Mon Sep 17 00:00:00 2001
From: Ignacio Ruiz <ignacio.ruizmartin@heetch.com>
Date: Wed, 6 Apr 2022 11:10:09 +0200
Subject: [PATCH 14/14] Add link to kotlinx.serialization

---
 .../src/commonMain/kotlin/dev/gitlive/firebase/Polymorphic.kt | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/Polymorphic.kt b/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/Polymorphic.kt
index ace429795..aceb6002f 100644
--- a/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/Polymorphic.kt
+++ b/firebase-common/src/commonMain/kotlin/dev/gitlive/firebase/Polymorphic.kt
@@ -6,6 +6,10 @@ import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.findPolymorphicSerializer
 import kotlinx.serialization.internal.AbstractPolymorphicSerializer
 
+/*
+ * This code was inspired on polymorphic json serialization of kotlinx.serialization.
+ * See https://github.com/Kotlin/kotlinx.serialization/blob/master/formats/json/commonMain/src/kotlinx/serialization/json/internal/Polymorphic.kt
+ */
 @Suppress("UNCHECKED_CAST")
 internal fun <T> FirebaseEncoder.encodePolymorphically(
     serializer: SerializationStrategy<T>,