[IJ Plugin] Play nice with IDEs without Kotlin/Gradle (#6358)

* Fix missing Kotlin classes when running inspections in IDEs without the Kotlin plugin

* Mark the Gradle plugin as optional, and move all components specific to Apollo Kotlin to the Kotlin plugin dependency file.

* Remove duplicate action

intellij-plugin/src/main/kotlin/com/apollographql/ijplugin/project/ApolloProjectManagerListener.kt

@@ -9,6 +9,8 @@ import com.apollographql.ijplugin.settings.ProjectSettingsService
 import com.apollographql.ijplugin.studio.fieldinsights.FieldInsightsService
 import com.apollographql.ijplugin.studio.sandbox.SandboxService
 import com.apollographql.ijplugin.telemetry.TelemetryService
+import com.apollographql.ijplugin.util.isGradlePluginPresent
+import com.apollographql.ijplugin.util.isKotlinPluginPresent
 import com.apollographql.ijplugin.util.isLspAvailable
 import com.apollographql.ijplugin.util.logd
 import com.intellij.openapi.components.service
@@ -23,15 +25,18 @@ internal class ApolloProjectManagerListener : ProjectManagerListener {
 
     // Initialize all services on project open.
     // But wait for 'smart mode' to do it.
+    // Most of these services can't operate without the Kotlin and Gradle plugins (e.g. in RustRover).
     DumbService.getInstance(project).runWhenSmart {
       logd("apolloVersion=" + project.apolloProjectService.apolloVersion)
-      project.service<ApolloCodegenService>()
-      project.service<GraphQLConfigService>()
-      project.service<GradleToolingModelService>()
-      project.service<ProjectSettingsService>()
-      project.service<SandboxService>()
-      project.service<FieldInsightsService>()
-      project.service<TelemetryService>()
+      if (isKotlinPluginPresent && isGradlePluginPresent) {
+        project.service<ApolloCodegenService>()
+        project.service<GraphQLConfigService>()
+        project.service<GradleToolingModelService>()
+        project.service<ProjectSettingsService>()
+        project.service<SandboxService>()
+        project.service<FieldInsightsService>()
+        project.service<TelemetryService>()
+      }
       if (isLspAvailable) {
         project.service<ApolloLspProjectService>()
         application.service<ApolloLspAppService>()

intellij-plugin/src/main/kotlin/com/apollographql/ijplugin/settings/SettingsComponent.kt

@@ -3,6 +3,8 @@ package com.apollographql.ijplugin.settings
 import com.apollographql.ijplugin.ApolloBundle
 import com.apollographql.ijplugin.project.apolloProjectService
 import com.apollographql.ijplugin.settings.studio.ApiKeyDialog
+import com.apollographql.ijplugin.util.isGradlePluginPresent
+import com.apollographql.ijplugin.util.isKotlinPluginPresent
 import com.intellij.openapi.observable.properties.PropertyGraph
 import com.intellij.openapi.project.Project
 import com.intellij.ui.AddEditRemovePanel
@@ -32,21 +34,22 @@ class SettingsComponent(private val project: Project) {
   private var addEditRemovePanel: AddEditRemovePanel<ApolloKotlinServiceConfiguration>? = null
 
   val panel: JPanel = panel {
+    // Some options are irrelevant without the Kotlin or Gradle plugins (e.g. in RustRover).
     group(ApolloBundle.message("settings.codegen.title")) {
       row {
         chkAutomaticCodegenTriggering = checkBox(ApolloBundle.message("settings.codegen.automaticCodegenTriggering.text"))
             .comment(ApolloBundle.message("settings.codegen.automaticCodegenTriggering.comment"))
             .bindSelected(automaticCodegenTriggeringProperty)
             .component
       }
-    }
+    }.visible(isKotlinPluginPresent && isGradlePluginPresent)
     group(ApolloBundle.message("settings.graphqlPlugin.title")) {
       row {
         checkBox(ApolloBundle.message("settings.graphqlPlugin.contributeConfigurationToGraphqlPlugin.text"))
             .comment(ApolloBundle.message("settings.graphqlPlugin.contributeConfigurationToGraphqlPlugin.comment"))
             .bindSelected(contributeConfigurationToGraphqlPluginProperty)
       }
-    }
+    }.visible(isKotlinPluginPresent && isGradlePluginPresent)
     group(ApolloBundle.message("settings.studio.title")) {
       if (!project.apolloProjectService.apolloVersion.isAtLeastV4) {
         row { label(ApolloBundle.message("settings.studio.apiKeys.needV4.message")) }
@@ -98,7 +101,7 @@ class SettingsComponent(private val project: Project) {
               .comment(ApolloBundle.message("settings.studio.apiKeys.comment"))
         }
       }
-    }
+    }.visible(isKotlinPluginPresent && isGradlePluginPresent)
 
     group(ApolloBundle.message("settings.telemetry.telemetryEnabled.title")) {
       row {

intellij-plugin/src/main/kotlin/com/apollographql/ijplugin/util/Environment.kt

@@ -7,3 +7,5 @@ val isAndroidPluginPresent = runCatching { Class.forName("com.android.ddmlib.And
 val isJavaPluginPresent = runCatching { Class.forName("com.intellij.psi.PsiJavaFile") }.isSuccess
 
 val isKotlinPluginPresent = runCatching { Class.forName("org.jetbrains.kotlin.psi.KtFile") }.isSuccess
+
+val isGradlePluginPresent = runCatching { Class.forName("org.jetbrains.plugins.gradle.util.GradleConstants") }.isSuccess

intellij-plugin/src/main/resources/META-INF/com.apollographql.ijplugin-gradle.xml

@@ -0,0 +1,9 @@
+<idea-plugin>
+  <!-- Add here declarations that only work in presence of the Gradle plugin -->
+
+  <extensions defaultExtensionNs="com.intellij">
+    <!-- Listen to Gradle sync -->
+    <externalSystemTaskNotificationListener implementation="com.apollographql.ijplugin.gradle.GradleListener" />
+
+  </extensions>
+</idea-plugin>