Migrate catalog app to Kotlin Multiplatform

catalog/build.gradle.kts

@@ -1,14 +1,21 @@
+import org.jetbrains.kotlin.gradle.ExperimentalWasmDsl
+import org.jetbrains.kotlin.gradle.targets.js.webpack.KotlinWebpackConfig
+
 plugins {
-  alias(libs.plugins.android.application)
-  alias(libs.plugins.kotlin.android)
+  id("org.jetbrains.kotlin.multiplatform")
+  id("com.android.application")
+  id("org.jetbrains.kotlin.plugin.compose")
+  id("org.jetbrains.compose")
+  id("org.jetbrains.kotlin.plugin.serialization")
   alias(libs.plugins.androidx.navigation.safeargs)
 }
 
-configureRuler()
+// configureRuler()
 
 android {
   namespace = "com.google.android.fhir.catalog"
   compileSdk = Sdk.COMPILE_SDK
+
   defaultConfig {
     applicationId = Releases.Catalog.applicationId
     minSdk = Sdk.MIN_SDK
@@ -17,47 +24,86 @@ android {
     versionName = Releases.Catalog.versionName
     testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
   }
-
-  buildFeatures { viewBinding = true }
-
   buildTypes {
     release {
       isMinifyEnabled = true
       proguardFiles(getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro")
     }
   }
   compileOptions {
-    // Flag to enable support for the new language APIs
-    // See https://developer.android.com/studio/write/java8-support
-    isCoreLibraryDesugaringEnabled = true
+    sourceCompatibility = JavaVersion.VERSION_11
+    targetCompatibility = JavaVersion.VERSION_11
   }
-
   packaging {
     resources.excludes.addAll(
       listOf("META-INF/ASL2.0", "META-INF/ASL-2.0.txt", "META-INF/LGPL-3.0.txt"),
     )
   }
-  kotlin { jvmToolchain(11) }
 }
 
-dependencies {
-  androidTestImplementation(libs.androidx.test.espresso.core)
-  androidTestImplementation(libs.androidx.test.ext.junit)
-
-  coreLibraryDesugaring(libs.desugar.jdk.libs)
-
-  implementation(libs.androidx.appcompat)
-  implementation(libs.androidx.constraintlayout)
-  implementation(libs.androidx.core)
-  implementation(libs.androidx.fragment)
-  implementation(libs.androidx.navigation.fragment)
-  implementation(libs.androidx.navigation.ui)
-  implementation(libs.kotlin.stdlib)
-  implementation(libs.material)
-  implementation(project(path = ":contrib:barcode"))
-  implementation(project(path = ":contrib:locationwidget"))
-  implementation(project(path = ":datacapture"))
-  implementation(project(path = ":engine"))
-
-  testImplementation(libs.junit)
+kotlin {
+  androidTarget {
+    compilerOptions { jvmTarget.set(org.jetbrains.kotlin.gradle.dsl.JvmTarget.JVM_11) }
+  }
+
+  jvm("desktop")
+
+  @OptIn(ExperimentalWasmDsl::class)
+  wasmJs {
+    browser {
+      val rootProjectDir = rootProject.projectDir.path
+      commonWebpackConfig {
+        devServer =
+          (devServer ?: KotlinWebpackConfig.DevServer()).copy(
+            static = (devServer?.static ?: mutableListOf()).apply { add(rootProjectDir) },
+          )
+      }
+    }
+    binaries.executable()
+  }
+
+  listOf(
+      iosX64(),
+      iosArm64(),
+      iosSimulatorArm64(),
+    )
+    .forEach { iosTarget ->
+      iosTarget.binaries.framework {
+        baseName = "CatalogKit"
+        isStatic = true
+      }
+    }
+
+  sourceSets {
+    androidMain.dependencies {
+      implementation(libs.androidx.appcompat)
+      implementation(libs.androidx.constraintlayout)
+      implementation(libs.androidx.core)
+      implementation(libs.androidx.fragment)
+      implementation(libs.material)
+      // TODO restore after these libraries are migrated to Kotlin Multiplatform
+      //      implementation(project(":engine"))
+      //      implementation(project(":contrib:barcode"))
+      //      implementation(project(":contrib:locationwidget"))
+    }
+    commonMain.dependencies {
+      implementation(compose.runtime)
+      implementation(compose.foundation)
+      implementation(compose.material3)
+      implementation(compose.ui)
+      implementation(compose.components.resources)
+      implementation(compose.components.uiToolingPreview)
+      implementation(libs.androidx.lifecycle.viewmodel.compose)
+      implementation(libs.androidx.lifecycle.runtime.compose)
+      implementation(libs.material.icons.extended)
+      implementation(libs.kermit)
+      implementation(libs.kotlin.fhir)
+      implementation(libs.kotlinx.serialization.json)
+      implementation(libs.kotlinx.coroutines.core)
+      implementation(libs.navigation.compose)
+      implementation(project(":datacapture-kmp"))
+    }
+
+    val desktopMain by getting { dependencies { implementation(compose.desktop.currentOs) } }
+  }
 }

catalog/src/main/java/com/google/android/fhir/catalog/DemoQuestionnaireViewModel.kt → catalog/src/androidMain/kotlin/com/google/android/fhir/catalog/CatalogApplication.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2022-2023 Google LLC
+ * Copyright 2022-2026 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,15 +17,11 @@
 package com.google.android.fhir.catalog
 
 import android.app.Application
-import androidx.lifecycle.AndroidViewModel
-import androidx.lifecycle.SavedStateHandle
-import ca.uhn.fhir.context.FhirContext
-import ca.uhn.fhir.context.FhirVersionEnum
-import org.hl7.fhir.r4.model.QuestionnaireResponse
 
-class DemoQuestionnaireViewModel(application: Application, private val state: SavedStateHandle) :
-  AndroidViewModel(application) {
+class CatalogApplication : Application() {
 
-  fun getQuestionnaireResponseJson(response: QuestionnaireResponse) =
-    FhirContext.forCached(FhirVersionEnum.R4).newJsonParser().encodeResourceToString(response)
+  override fun onCreate() {
+    super.onCreate()
+    // TODO Restore QueryResolver for DataCaptureConfigu once FHIR Engine is migrated to KMP
+  }
 }

catalog/src/androidMain/kotlin/com/google/android/fhir/catalog/MainActivity.kt

@@ -0,0 +1,28 @@
+/*
+ * Copyright 2021-2026 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.android.fhir.catalog
+
+import android.os.Bundle
+import androidx.activity.ComponentActivity
+import androidx.activity.compose.setContent
+
+class MainActivity : ComponentActivity() {
+  override fun onCreate(savedInstanceState: Bundle?) {
+    super.onCreate(savedInstanceState)
+    setContent { App() }
+  }
+}

catalog/src/main/res/mipmap-anydpi-v26/ic_card_file_box_round.xml → catalog/src/androidMain/res/mipmap-anydpi-v26/ic_card_file_box_round.xml

@@ -1,5 +1,9 @@
 <?xml version="1.0" encoding="utf-8" ?>
-<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+<adaptive-icon
+    xmlns:tools="http://schemas.android.com/tools"
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    tools:ignore="MonochromeLauncherIcon"
+>
     <background android:drawable="@color/ic_card_file_box_background" />
     <foreground android:drawable="@mipmap/ic_card_file_box_foreground" />
 </adaptive-icon>

catalog/src/main/res/values-night/colors.xml → catalog/src/androidMain/res/values-night/colors.xml

@@ -15,6 +15,38 @@
  limitations under the License.
 -->
 <resources>
+    <color name="primary_blue_80">#A8C7FA</color>
+    <color name="ic_card_file_box_background">#3B5CFF</color>
+    <color name="onPrimary_blue_20">#062E6F</color>
+    <color name="primaryContainer_blue_30">#0842A0</color>
+    <color name="onPrimaryContainer_blue_90">#D3E3FD</color>
+
+    <color name="secondary_blue_80">#7FCFFF</color>
+    <color name="onSecondary_blue_20">#003355</color>
+    <color name="secondaryContainer_blue_30">#004A77</color>
+    <color name="onSecondaryContainer_blue_90">#C2E7FF</color>
+
+    <color name="tertiary_green_80">#91D5A3</color>
+    <color name="onTertiary_green_20">#0A3818</color>
+    <color name="tertiaryContainer_green_30">#0F5223</color>
+    <color name="onTertiaryContainer_green_90">#C4EED0</color>
+
+    <color name="error_red_80">#F2B8B5</color>
+    <color name="errorContainer_red_20">#601410</color>
+    <color name="onError_red_30">#8C1D18</color>
+    <color name="onErrorContainer_red_90">#F9DEDC</color>
+
+    <color name="background_neutral_10">#1F1F1F</color>
+    <color name="onBackground_neutral_90">#E3E3E3</color>
+
+    <color name="surface_neutral_10">#1F1F1F</color>
+    <color name="onSurface_neutral_90">#E3E3E3</color>
+
+    <color name="surfaceVariant_neutral_variant_30">#444746</color>
+    <color name="onSurfaceVariant_neutral_variant_80">#C4C7C5</color>
+
+    <color name="outline_neutral_variant_60">#8E918F</color>
+
     <color name="custom_style_primary_100">#000000</color>
     <color name="custom_style_primary_200">#0C0A20</color>
     <color name="custom_style_primary_300">#201441</color>

catalog/src/main/res/values-night/themes.xml → catalog/src/androidMain/res/values-night/themes.xml

@@ -1,18 +1,3 @@
-<!--
- Copyright 2020 Google LLC
-
- Licensed under the Apache License, Version 2.0 (the "License");
- you may not use this file except in compliance with the License.
- You may obtain a copy of the License at
-
-      http://www.apache.org/licenses/LICENSE-2.0
-
- Unless required by applicable law or agreed to in writing, software
- distributed under the License is distributed on an "AS IS" BASIS,
- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- See the License for the specific language governing permissions and
- limitations under the License.
--->
 <resources xmlns:tools="http://schemas.android.com/tools">
     <!-- Base application theme. -->
     <style