From 70ec1f7de703c9677cedfe89aef1fde255b724a0 Mon Sep 17 00:00:00 2001
From: Han Yin <han.yin@arm.com>
Date: Fri, 27 Jun 2025 11:58:29 -0700
Subject: [PATCH] di: add a stub TierDetection; provide both actual impl and
 stub in AppModule

---
 .../java/com/example/llama/di/AppModule.kt    | 11 +++++++++++
 .../example/llama/engine/StubTierDetection.kt | 19 +++++++++++++++++++
 .../llama/viewmodel/SettingsViewModel.kt      |  6 ++++++
 3 files changed, 36 insertions(+)
 create mode 100644 examples/llama.android/app/src/main/java/com/example/llama/engine/StubTierDetection.kt

diff --git a/examples/llama.android/app/src/main/java/com/example/llama/di/AppModule.kt b/examples/llama.android/app/src/main/java/com/example/llama/di/AppModule.kt
index 658096617e..ff53da9d62 100644
--- a/examples/llama.android/app/src/main/java/com/example/llama/di/AppModule.kt
+++ b/examples/llama.android/app/src/main/java/com/example/llama/di/AppModule.kt
@@ -3,6 +3,7 @@ package com.example.llama.di
 import android.content.Context
 import android.llama.cpp.InferenceEngine
 import android.llama.cpp.KleidiLlama
+import android.llama.cpp.TierDetection
 import android.llama.cpp.gguf.GgufMetadataReader
 import com.example.llama.data.local.AppDatabase
 import com.example.llama.data.remote.HuggingFaceApiService
@@ -18,6 +19,7 @@ import com.example.llama.engine.InferenceService
 import com.example.llama.engine.InferenceServiceImpl
 import com.example.llama.engine.ModelLoadingService
 import com.example.llama.engine.StubInferenceEngine
+import com.example.llama.engine.StubTierDetection
 import com.example.llama.monitoring.PerformanceMonitor
 import dagger.Binds
 import dagger.Module
@@ -71,6 +73,15 @@ internal abstract class AppModule {
             }
         }
 
+        @Provides
+        fun provideTierDetection(@ApplicationContext context: Context): TierDetection {
+            return if (USE_STUB_ENGINE) {
+                StubTierDetection
+            } else {
+                KleidiLlama.getTierDetection(context)
+            }
+        }
+
         @Provides
         fun providePerformanceMonitor(@ApplicationContext context: Context) = PerformanceMonitor(context)
 
diff --git a/examples/llama.android/app/src/main/java/com/example/llama/engine/StubTierDetection.kt b/examples/llama.android/app/src/main/java/com/example/llama/engine/StubTierDetection.kt
new file mode 100644
index 0000000000..b120ad2c41
--- /dev/null
+++ b/examples/llama.android/app/src/main/java/com/example/llama/engine/StubTierDetection.kt
@@ -0,0 +1,19 @@
+package com.example.llama.engine
+
+import android.llama.cpp.LLamaTier
+import android.llama.cpp.TierDetection
+import android.util.Log
+
+/**
+ * A stub [TierDetection] for agile development & testing
+ */
+object StubTierDetection : TierDetection {
+    private val tag = StubTierDetection::class.java.simpleName
+
+    override val detectedTier: LLamaTier?
+        get() = LLamaTier.T2
+
+    override fun clearCache() {
+        Log.d(tag, "Cache cleared")
+    }
+}
diff --git a/examples/llama.android/app/src/main/java/com/example/llama/viewmodel/SettingsViewModel.kt b/examples/llama.android/app/src/main/java/com/example/llama/viewmodel/SettingsViewModel.kt
index 42011d5162..7105d57c80 100644
--- a/examples/llama.android/app/src/main/java/com/example/llama/viewmodel/SettingsViewModel.kt
+++ b/examples/llama.android/app/src/main/java/com/example/llama/viewmodel/SettingsViewModel.kt
@@ -1,5 +1,7 @@
 package com.example.llama.viewmodel
 
+import android.llama.cpp.LLamaTier
+import android.llama.cpp.TierDetection
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import com.example.llama.data.preferences.UserPreferences
@@ -26,6 +28,7 @@ class SettingsViewModel @Inject constructor(
     private val userPreferences: UserPreferences,
     private val performanceMonitor: PerformanceMonitor,
     private val modelRepository: ModelRepository,
+    private val tierDetection: TierDetection,
 ) : ViewModel() {
 
     // Storage usage metrics
@@ -57,6 +60,9 @@ class SettingsViewModel @Inject constructor(
     private val _themeMode = MutableStateFlow(UserPreferences.THEME_MODE_AUTO)
     val themeMode: StateFlow<Int> = _themeMode.asStateFlow()
 
+    val detectedTier: LLamaTier?
+        get() = tierDetection.detectedTier
+
     init {
         viewModelScope.launch {
             // Load user preferences