Feature: Introduce ModelRepository and ModelsManagementViewModel; update AppModule

examples/llama.android/app/src/main/java/com/example/llama/revamp/data/repository/ModelRepository.kt

@@ -0,0 +1,51 @@
+package com.example.llama.revamp.data.repository
+
+import android.content.Context
+import android.net.Uri
+import com.example.llama.revamp.data.model.ModelInfo
+import dagger.hilt.android.qualifiers.ApplicationContext
+import javax.inject.Inject
+import javax.inject.Singleton
+
+interface ModelRepository {
+    suspend fun getModels(): List<ModelInfo>
+    suspend fun deleteModel(modelId: String)
+    suspend fun deleteModels(modelIds: Collection<String>)
+    suspend fun importModel(uri: Uri): ModelInfo
+    suspend fun getStorageMetrics(): StorageMetrics
+}
+
+@Singleton
+class ModelRepositoryImpl @Inject constructor(
+    @ApplicationContext private val context: Context,
+    // TODO-han.yin: Add model DAO
+) : ModelRepository {
+
+    override suspend fun getModels(): List<ModelInfo> {
+        // In a real implementation, this would load from database
+        return ModelInfo.getSampleModels()
+    }
+
+    override suspend fun deleteModel(modelId: String) {
+        // Stub - would delete from filesystem and database
+    }
+
+    override suspend fun deleteModels(modelIds: Collection<String>) {
+        // Stub - would delete from filesystem and database
+    }
+
+    override suspend fun importModel(uri: Uri): ModelInfo {
+        // Stub - would copy file and extract metadata
+        return ModelInfo.getSampleModels().first()
+    }
+
+    override suspend fun getStorageMetrics(): StorageMetrics {
+        // Stub - would calculate from actual storage
+        return StorageMetrics(14.6f, 32.0f)
+    }
+}
+
+data class StorageMetrics(
+    val usedGB: Float,
+    val totalGB: Float
+)

examples/llama.android/app/src/main/java/com/example/llama/revamp/di/AppModule.kt

@@ -2,8 +2,11 @@ package com.example.llama.revamp.di
 
 import android.content.Context
 import com.example.llama.revamp.data.local.AppDatabase
+import com.example.llama.revamp.data.repository.ModelRepository
+import com.example.llama.revamp.data.repository.ModelRepositoryImpl
 import com.example.llama.revamp.engine.InferenceEngine
 import com.example.llama.revamp.monitoring.PerformanceMonitor
+import dagger.Binds
 import dagger.Module
 import dagger.Provides
 import dagger.hilt.InstallIn
@@ -13,8 +16,12 @@ import javax.inject.Singleton
 
 @Module
 @InstallIn(SingletonComponent::class)
-object AppModule {
+abstract class AppModule {
 
+    @Binds
+    abstract fun bindsModelsRepository(impl: ModelRepositoryImpl): ModelRepository
+
+    companion object {
         @Provides
         @Singleton
         fun provideInferenceEngine() = InferenceEngine()
@@ -28,4 +35,5 @@ object AppModule {
 
         @Provides
         fun providesSystemPromptDao(appDatabase: AppDatabase) = appDatabase.systemPromptDao()
+    }
 }

examples/llama.android/app/src/main/java/com/example/llama/revamp/viewmodel/ModelsManagementViewModel.kt

@@ -0,0 +1,119 @@
+package com.example.llama.revamp.viewmodel
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import com.example.llama.revamp.data.model.ModelInfo
+import com.example.llama.revamp.data.repository.ModelRepository
+import com.example.llama.revamp.data.repository.StorageMetrics
+import dagger.hilt.android.lifecycle.HiltViewModel
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.launch
+import javax.inject.Inject
+
+@HiltViewModel
+class ModelsManagementViewModel @Inject constructor(
+    private val modelRepository: ModelRepository
+) : ViewModel() {
+
+    // Sort order state
+    private val _sortOrder = MutableStateFlow(ModelSortOrder.NAME_ASC)
+    val sortOrder: StateFlow<ModelSortOrder> = _sortOrder.asStateFlow()
+
+    // Available models
+    private val _availableModels = MutableStateFlow<List<ModelInfo>>(emptyList())
+    val availableModels: StateFlow<List<ModelInfo>> = _availableModels.asStateFlow()
+
+    // Storage metrics
+    private val _storageMetrics = MutableStateFlow(StorageMetrics(0f, 0f))
+    val storageMetrics: StateFlow<StorageMetrics> = _storageMetrics.asStateFlow()
+
+    init {
+        // Initial data load
+        viewModelScope.launch {
+            loadModels()
+            loadStorageMetrics()
+        }
+
+        // Observe sort order changes and apply sorting
+        viewModelScope.launch {
+            sortOrder.collect { order -> sortModels(order) }
+        }
+    }
+
+    private fun loadModels() {
+        // TODO-han.yin: Stub for now. Would load from the repository
+        _availableModels.value = ModelInfo.getSampleModels()
+        sortModels(_sortOrder.value)
+    }
+
+    private fun loadStorageMetrics() {
+        // TODO-han.yin: Stub for now. Would load from storage
+        _storageMetrics.value = StorageMetrics(14.6f, 32.0f)
+    }
+
+    private fun sortModels(order: ModelSortOrder) {
+        val sorted = when (order) {
+            ModelSortOrder.NAME_ASC -> _availableModels.value.sortedBy { it.name }
+            ModelSortOrder.NAME_DESC -> _availableModels.value.sortedByDescending { it.name }
+            ModelSortOrder.SIZE_ASC -> _availableModels.value.sortedBy { it.sizeInBytes }
+            ModelSortOrder.SIZE_DESC -> _availableModels.value.sortedByDescending { it.sizeInBytes }
+            ModelSortOrder.LAST_USED -> _availableModels.value.sortedByDescending { it.lastUsed ?: 0 }
+        }
+        _availableModels.value = sorted
+    }
+
+    fun setSortOrder(order: ModelSortOrder) {
+        _sortOrder.value = order
+    }
+
+    fun viewModelDetails(modelId: String) {
+        // TODO-han.yin: Stub for now. Would navigate to model details screen or show dialog
+    }
+
+    fun deleteModel(modelId: String) {
+        // Remove model from list
+        _availableModels.value = _availableModels.value.filter { it.id != modelId }
+
+        viewModelScope.launch {
+            // TODO-han.yin: Stub for now this would delete from storage
+            modelRepository.deleteModel(modelId)
+            updateStorageMetrics()
+        }
+    }
+
+    fun deleteModels(models: Map<String, ModelInfo>) {
+        val modelIds = models.keys
+        _availableModels.value = _availableModels.value.filter { !modelIds.contains(it.id) }
+
+        viewModelScope.launch {
+            modelRepository.deleteModels(modelIds)
+            updateStorageMetrics()
+        }
+    }
+
+    fun importLocalModel() {
+        // TODO-han.yin: Stub for now. Would open file picker and import model
+    }
+
+    private fun updateStorageMetrics() {
+        // Recalculate storage metrics after model changes
+        // TODO-han.yin: Stub for now. Would query actual storage
+        val totalSize = _availableModels.value.sumOf { it.sizeInBytes }
+        _storageMetrics.value = StorageMetrics(
+            (totalSize / 1_000_000_000.0).toFloat(),
+            32.0f
+        )
+    }
+}
+
+enum class ModelSortOrder {
+    NAME_ASC,
+    NAME_DESC,
+    SIZE_ASC,
+    SIZE_DESC,
+    LAST_USED
+}
+
+