ADFA-4747: Fix Add-import code action not appearing on unresolved references

idetooltips/src/main/java/com/itsaky/androidide/idetooltips/TooltipTag.kt

@@ -79,6 +79,7 @@ object TooltipTag {
 	const val EDITOR_CODE_ACTIONS_GEN_TO_STRING_DIALOG = "editor.codeactions.gentostring.dialog"
 	const val EDITOR_CODE_ACTIONS_UNUSED_IMPORTS = "editor.codeactions.unusedimports"
 	const val EDITOR_CODE_ACTIONS_ORGANIZE_IMPORTS = "editor.codeactions.organizeimports"
+	const val EDITOR_CODE_ACTIONS_KT_FIX_IMPORTS = "editor.codeactions.kotlin.fiximports"
 
 	const val EXIT_TO_MAIN = "exit.to.main"
 

lsp/kotlin/src/main/java/com/itsaky/androidide/lsp/kotlin/actions/AddImportAction.kt

@@ -4,12 +4,10 @@ import com.itsaky.androidide.actions.ActionData
 import com.itsaky.androidide.actions.has
 import com.itsaky.androidide.actions.markInvisible
 import com.itsaky.androidide.actions.newDialogBuilder
-import com.itsaky.androidide.actions.require
 import com.itsaky.androidide.actions.requireFile
 import com.itsaky.androidide.idetooltips.TooltipTag
 import com.itsaky.androidide.lsp.kotlin.compiler.index.findSymbolBySimpleName
 import com.itsaky.androidide.lsp.kotlin.diagnostic.DiagnosticAction
-import com.itsaky.androidide.lsp.kotlin.diagnostic.KotlinDiagnosticExtra
 import com.itsaky.androidide.lsp.kotlin.utils.insertImport
 import com.itsaky.androidide.lsp.models.CodeActionItem
 import com.itsaky.androidide.lsp.models.CodeActionKind
@@ -18,22 +16,18 @@ import com.itsaky.androidide.lsp.models.DiagnosticItem
 import com.itsaky.androidide.lsp.models.DocumentChange
 import com.itsaky.androidide.lsp.models.TextEdit
 import com.itsaky.androidide.resources.R
+import com.itsaky.androidide.utils.flashError
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 import org.appdevforall.codeonthego.indexing.jvm.JvmSymbol
-import org.slf4j.LoggerFactory
 
 class AddImportAction : BaseKotlinCodeAction() {
 	override var titleTextRes: Int = R.string.action_import_classes
-	override var tooltipTag: String = TooltipTag.EDITOR_CODE_ACTIONS_FIX_IMPORTS
+	override var tooltipTag: String = TooltipTag.EDITOR_CODE_ACTIONS_KT_FIX_IMPORTS
 
 	override val id: String = "ide.editor.lsp.kt.diagnostics.addImport"
 	override var label: String = ""
 
-	companion object {
-		private val logger = LoggerFactory.getLogger(AddImportAction::class.java)
-	}
-
 	override fun prepare(data: ActionData) {
 		super.prepare(data)
 
@@ -42,37 +36,23 @@ class AddImportAction : BaseKotlinCodeAction() {
 			return
 		}
 
-		val extra = data.require<DiagnosticItem>().extra as? KotlinDiagnosticExtra
-		if (extra == null) {
-			markInvisible()
-			return
-		}
-
-		val action = extra.action
-		if (action !is DiagnosticAction.ResolveReference) {
-			markInvisible()
-			return
-		}
-
-		val env = extra.compilationEnv
-		val hasImportableSymbols =
-			env.ktSymbolIndex
-				.findSymbolBySimpleName(action.referenceName, limit = 0)
-				.any { it.kind.isClassifier }
-
-		if (!hasImportableSymbols) {
+		// Optimistic visibility: decide from the in-memory unresolved-reference marker only. The
+		// importable-classifier resolution runs in the background execAction; doing it here would be
+		// main-thread SQLite I/O, because fillMenu() calls prepare() synchronously on the UI thread.
+		val resolveReferenceActionDiagnostic =
+			data.findDiagnosticExtra<DiagnosticAction.ResolveReference>()
+		if (resolveReferenceActionDiagnostic == null) {
 			markInvisible()
 			return
 		}
 	}
 
 	override suspend fun execAction(data: ActionData): Map<JvmSymbol, List<TextEdit>> {
-		val (env, action) =
-			data.require<DiagnosticItem>().extra as? KotlinDiagnosticExtra
+		val (_, extra) =
+			data.findDiagnosticExtra<DiagnosticAction.ResolveReference>()
 				?: return emptyMap()
 
-		if (action !is DiagnosticAction.ResolveReference) return emptyMap()
-
+		val (env, action) = extra
 		val file = data.requireFile()
 		val nioPath = file.toPath()
 		val ktFile =
@@ -104,6 +84,7 @@ class AddImportAction : BaseKotlinCodeAction() {
 
 		if (result.isEmpty()) {
 			logger.warn("No classifiers to import.")
+			flashError(R.string.msg_no_imports_found)
 			return
 		}
 

lsp/kotlin/src/main/java/com/itsaky/androidide/lsp/kotlin/actions/BaseKotlinCodeAction.kt

@@ -13,6 +13,11 @@ import com.itsaky.androidide.actions.requireContext
 import com.itsaky.androidide.actions.requireFile
 import com.itsaky.androidide.lsp.api.ILanguageClient
 import com.itsaky.androidide.lsp.kotlin.KotlinLanguageServer
+import com.itsaky.androidide.lsp.kotlin.diagnostic.DiagnosticAction
+import com.itsaky.androidide.lsp.kotlin.diagnostic.KotlinDiagnosticExtra
+import com.itsaky.androidide.lsp.kotlin.diagnostic.asAction
+import com.itsaky.androidide.lsp.models.DiagnosticItem
+import com.itsaky.androidide.lsp.models.DiagnosticsInSelection
 import com.itsaky.androidide.utils.DocumentUtils
 import org.slf4j.Logger
 import org.slf4j.LoggerFactory
@@ -58,4 +63,26 @@ abstract class BaseKotlinCodeAction : EditorActionItem {
 		get() =
 			get<KotlinLanguageServer>()
 				?.client
+
+	internal inline fun <reified T : DiagnosticAction> DiagnosticItem.ktExtra(): KotlinDiagnosticExtra<T>? =
+		(extra as? KotlinDiagnosticExtra<*>)?.asAction<T>()
+
+	/**
+	 * Find the first [DiagnosticItem] in the current selection matching the given [predicate].
+	 * Prefers [DiagnosticsInSelection] (any matching diagnostic in the selected area); falls back
+	 * to the at-selection-start [DiagnosticItem] when no container is present.
+	 */
+	protected inline fun ActionData.findFirstDiagnosticItem(predicate: (DiagnosticItem) -> Boolean): DiagnosticItem? =
+		get<DiagnosticsInSelection>()
+			?.let { return it.diagnostics.firstOrNull(predicate) }
+			?: get<DiagnosticItem>()?.takeIf(predicate)
+
+	/**
+	 * Find the first in-selection [DiagnosticItem] whose extra carries a [T] action, paired with the
+	 * typed [KotlinDiagnosticExtra]. Carries the type evidence through so callers don't re-extract.
+	 */
+	internal inline fun <reified T : DiagnosticAction> ActionData.findDiagnosticExtra(): Pair<DiagnosticItem, KotlinDiagnosticExtra<T>>? {
+		val item = findFirstDiagnosticItem { it.ktExtra<T>() != null } ?: return null
+		return item to item.ktExtra<T>()!!
+	}
 }

lsp/kotlin/src/main/java/com/itsaky/androidide/lsp/kotlin/actions/ImplementMembersAction.kt

@@ -26,7 +26,6 @@ import org.jetbrains.kotlin.com.intellij.openapi.util.TextRange
 import org.jetbrains.kotlin.com.intellij.psi.util.PsiTreeUtil
 import org.jetbrains.kotlin.psi.KtClassOrObject
 import org.jetbrains.kotlin.psi.KtFile
-import org.slf4j.LoggerFactory
 import java.nio.file.Path
 
 class ImplementMembersAction : BaseKotlinCodeAction() {
@@ -35,10 +34,6 @@ class ImplementMembersAction : BaseKotlinCodeAction() {
 	override val id: String = "ide.editor.lsp.kt.implementMembers"
 	override var label: String = ""
 
-	companion object {
-		private val logger = LoggerFactory.getLogger(ImplementMembersAction::class.java)
-	}
-
 	// Intentionally no prepare() visibility gate: the action is visible on any Kotlin file (BaseKotlinCodeAction
 	// only checks the file type) and simply produces no edit when the enclosing class/object has nothing to
 	// implement. Deciding that up front needs a K2 analysis session, which is too costly for prepare() (UI

lsp/kotlin/src/main/java/com/itsaky/androidide/lsp/kotlin/actions/NullSafetyAction.kt

@@ -1,25 +1,22 @@
 package com.itsaky.androidide.lsp.kotlin.actions
 
 import com.itsaky.androidide.actions.ActionData
-import com.itsaky.androidide.actions.get
 import com.itsaky.androidide.actions.markInvisible
 import com.itsaky.androidide.actions.newDialogBuilder
 import com.itsaky.androidide.actions.requireContext
 import com.itsaky.androidide.actions.requireFile
 import com.itsaky.androidide.lsp.kotlin.compiler.read
 import com.itsaky.androidide.lsp.kotlin.diagnostic.DiagnosticAction
-import com.itsaky.androidide.lsp.kotlin.diagnostic.KotlinDiagnosticExtra
 import com.itsaky.androidide.lsp.kotlin.utils.NullSafetyKind
 import com.itsaky.androidide.lsp.kotlin.utils.NullSafetyVariant
 import com.itsaky.androidide.lsp.kotlin.utils.findNullableMemberAccess
 import com.itsaky.androidide.lsp.kotlin.utils.nullSafetyVariants
 import com.itsaky.androidide.lsp.models.CodeActionItem
 import com.itsaky.androidide.lsp.models.CodeActionKind
 import com.itsaky.androidide.lsp.models.Command
-import com.itsaky.androidide.lsp.models.DiagnosticItem
-import com.itsaky.androidide.lsp.models.DiagnosticsInSelection
 import com.itsaky.androidide.lsp.models.DocumentChange
 import com.itsaky.androidide.resources.R
+import kotlinx.coroutines.CancellationException
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 
@@ -38,32 +35,23 @@ class NullSafetyAction : BaseKotlinCodeAction() {
 	override val id: String = "ide.editor.lsp.kt.diagnostics.nullSafety"
 	override var label: String = ""
 
-	/**
-	 * The first null-safety-fixable diagnostic in the selection. Prefers [DiagnosticsInSelection]
-	 * (any matching diagnostic in the selected region); falls back to the at-selection-start
-	 * [DiagnosticItem] when no container is present.
-	 */
-	private fun ActionData.nullSafetyDiagnostic(): DiagnosticItem? {
-		val predicate = { d: DiagnosticItem ->
-			(d.extra as? KotlinDiagnosticExtra)?.action == DiagnosticAction.NullSafetyFix
-		}
-		get<DiagnosticsInSelection>()?.let { return it.diagnostics.firstOrNull(predicate) }
-		return get<DiagnosticItem>()?.takeIf(predicate)
-	}
-
 	override fun prepare(data: ActionData) {
 		super.prepare(data)
 
-		if (!visible || data.nullSafetyDiagnostic() == null) {
+		val nullSafetyFixDiagnostic =
+			data.findDiagnosticExtra<DiagnosticAction.NullSafetyFix>()
+
+		if (!visible || nullSafetyFixDiagnostic == null) {
 			markInvisible()
 			return
 		}
 	}
 
 	override suspend fun execAction(data: ActionData): List<NullSafetyVariant> =
 		runCatching {
-			val diagnostic = data.nullSafetyDiagnostic() ?: return emptyList()
-			val extra = diagnostic.extra as? KotlinDiagnosticExtra ?: return emptyList()
+			val (diagnostic, extra) =
+				data.findDiagnosticExtra<DiagnosticAction.NullSafetyFix>()
+					?: return emptyList()
 
 			val nioPath = data.requireFile().toPath()
 
@@ -85,6 +73,7 @@ class NullSafetyAction : BaseKotlinCodeAction() {
 				nullSafetyVariants(qe)
 			}
 		}.getOrElse { e ->
+			if (e is CancellationException) throw e
 			logger.warn("Failed to compute null-safety fixes", e)
 			emptyList()
 		}

lsp/kotlin/src/main/java/com/itsaky/androidide/lsp/kotlin/compiler/index/KtSymbolIndex.kt

@@ -336,8 +336,16 @@ internal fun KtSymbolIndex.filesForPackage(packageFqn: String) = fileIndex.getFi
 
 internal fun KtSymbolIndex.subpackageNames(packageFqn: String) = fileIndex.getSubpackageNames(packageFqn)
 
+/**
+ * Returns source- and library-index symbols whose simple name equals [name].
+ *
+ * [limit] `<= 0` means unbounded, honoring the same convention as
+ * [org.appdevforall.codeonthego.indexing.api.ReadableIndex.query] ("If IndexQuery.limit is 0, all
+ * matches are emitted"). A plain `take(limit)` would turn the common `limit = 0` call into
+ * `take(0)`, silently yielding no results.
+ */
 internal fun KtSymbolIndex.findSymbolBySimpleName(
 	name: String,
 	limit: Int,
 ) = (sourceIndex.findBySimpleName(name, 0) + libraryIndex.findBySimpleName(name, 0))
-	.take(limit)
+	.let { if (limit <= 0) it else it.take(limit) }

lsp/kotlin/src/main/java/com/itsaky/androidide/lsp/kotlin/diagnostic/KotlinDiagnosticProvider.kt

@@ -23,11 +23,15 @@ import java.nio.file.Path
 
 private val logger = LoggerFactory.getLogger("KotlinDiagnosticProvider")
 
-internal data class KotlinDiagnosticExtra(
+internal data class KotlinDiagnosticExtra<out ActionT : DiagnosticAction>(
 	val compilationEnv: CompilationEnvironment,
-	val action: DiagnosticAction,
+	val action: ActionT,
 )
 
+@Suppress("UNCHECKED_CAST")
+internal inline fun <reified T : DiagnosticAction> KotlinDiagnosticExtra<*>?.asAction(): KotlinDiagnosticExtra<T>? =
+	if (this?.action is T) this as KotlinDiagnosticExtra<T> else null
+
 internal sealed interface DiagnosticAction {
 	data object None : DiagnosticAction
 
@@ -98,9 +102,19 @@ private fun doAnalyze(
 							// the KaLifetimeOwner diagnostic escape (see KotlinDiagnosticExtra).
 							val action =
 								when (diagnostic) {
-									is KaFirDiagnostic.UnresolvedReference -> DiagnosticAction.ResolveReference(diagnostic.reference)
-									is KaFirDiagnostic.UnsafeCall -> DiagnosticAction.NullSafetyFix
-									else -> DiagnosticAction.None
+									is KaFirDiagnostic.UnresolvedReference -> {
+										DiagnosticAction.ResolveReference(
+											diagnostic.reference,
+										)
+									}
+
+									is KaFirDiagnostic.UnsafeCall -> {
+										DiagnosticAction.NullSafetyFix
+									}
+
+									else -> {
+										DiagnosticAction.None
+									}
 								}
 
 							add(