Merge remote-tracking branch 'origin/cobaDatabase' into cobaDatabase

# Conflicts:
#	app/src/main/java/com/example/notebook/MainActivity.kt

app/build.gradle.kts

@@ -68,7 +68,7 @@ dependencies {
     debugImplementation(libs.ui.tooling)
     debugImplementation(libs.ui.test.manifest)
 
-    // Room Database - TAMBAHKAN INI SEMUA
+    // Room Database
     val roomVersion = "2.6.1"
     implementation("androidx.room:room-runtime:$roomVersion")
     implementation("androidx.room:room-ktx:$roomVersion")
@@ -80,4 +80,18 @@ dependencies {
     // ViewModel & Lifecycle
     implementation("androidx.lifecycle:lifecycle-viewmodel-compose:2.7.0")
     implementation("androidx.lifecycle:lifecycle-runtime-compose:2.7.0")
+
+    // Retrofit untuk HTTP requests
+    implementation("com.squareup.retrofit2:retrofit:2.9.0")
+    implementation("com.squareup.retrofit2:converter-gson:2.9.0")
+
+    // OkHttp untuk logging
+    implementation("com.squareup.okhttp3:okhttp:4.12.0")
+    implementation("com.squareup.okhttp3:logging-interceptor:4.12.0")
+
+    // Gson
+    implementation("com.google.code.gson:gson:2.10.1")
+
+    // PDF Support
+    implementation("com.tom-roush:pdfbox-android:2.0.27.0")
 }

app/src/main/java/com/example/notebook/MainActivity.kt

@@ -41,18 +41,12 @@ class MainActivity : ComponentActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContent {
-            var isDarkMode by remember { mutableStateOf(false) }
-
-            NotebookTheme(darkTheme = isDarkMode) {
+            NotebookTheme {
                 Surface(
                     modifier = Modifier.fillMaxSize(),
                     color = MaterialTheme.colorScheme.background
                 ) {
-                    NotebookApp(
-                        viewModel = viewModel,
-                        isDarkMode = isDarkMode,
-                        onThemeChange = { isDarkMode = it }
-                    )
+                    NotebookApp(viewModel = viewModel)
                 }
             }
         }
@@ -61,13 +55,10 @@ class MainActivity : ComponentActivity() {
 
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
-fun NotebookApp(
-    viewModel: NotebookViewModel,
-    isDarkMode: Boolean,
-    onThemeChange: (Boolean) -> Unit
-) {
+fun NotebookApp(viewModel: NotebookViewModel) {
     var selectedTabIndex by remember { mutableIntStateOf(0) }
     val tabs = listOf("Studio", "Chat", "Sources")
+    var showGoogleAppsMenu by remember { mutableStateOf(false) }
     var showSettingsMenu by remember { mutableStateOf(false) }
     var showAccountScreen by remember { mutableStateOf(false) }
     var chatInput by remember { mutableStateOf("") }
@@ -96,14 +87,14 @@ fun NotebookApp(
                         IconButton(onClick = { showSettingsMenu = true }) {
                             Icon(Icons.Filled.Settings, contentDescription = "Settings")
                         }
-                        SettingsMenu(
-                            expanded = showSettingsMenu,
-                            onDismiss = { showSettingsMenu = false },
-                            isDarkMode = isDarkMode,
-                            onThemeChange = onThemeChange
-                        )
+                        SettingsMenu(expanded = showSettingsMenu, onDismiss = { showSettingsMenu = false })
+                    }
+                    Box {
+                        IconButton(onClick = { showGoogleAppsMenu = true }) {
+                            Icon(Icons.Filled.Apps, contentDescription = "Google Apps")
+                        }
+                        GoogleAppsMenu(expanded = showGoogleAppsMenu, onDismiss = { showGoogleAppsMenu = false })
                     }
-
                     Box(
                         modifier = Modifier
                             .size(32.dp)
@@ -185,14 +176,14 @@ fun StudioScreen(viewModel: NotebookViewModel) {
     Column(
         modifier = Modifier
             .fillMaxSize()
-            .background(MaterialTheme.colorScheme.background)
+            .background(Color.White)
             .padding(16.dp)
     ) {
         Text(
             "Notebook terbaru",
             style = MaterialTheme.typography.titleLarge,
             fontWeight = FontWeight.Bold,
-            color = MaterialTheme.colorScheme.onBackground
+            color = Color.Black
         )
         Spacer(modifier = Modifier.height(16.dp))
 
@@ -224,9 +215,7 @@ fun NewNotebookCard(onClick: () -> Unit) {
             .height(120.dp)
             .clickable(onClick = onClick),
         shape = RoundedCornerShape(16.dp),
-        colors = CardDefaults.cardColors(
-            containerColor = MaterialTheme.colorScheme.surfaceVariant
-        )
+        colors = CardDefaults.cardColors(containerColor = Color(0xFFF0F4F7))
     ) {
         Column(
             modifier = Modifier.fillMaxSize(),
@@ -237,20 +226,13 @@ fun NewNotebookCard(onClick: () -> Unit) {
                 modifier = Modifier
                     .size(40.dp)
                     .clip(CircleShape)
-                    .background(MaterialTheme.colorScheme.secondaryContainer),
+                    .background(Color(0xFFE1E3E6)),
                 contentAlignment = Alignment.Center
             ) {
-                Icon(
-                    Icons.Default.Add,
-                    contentDescription = "Buat notebook baru",
-                    tint = MaterialTheme.colorScheme.onSecondaryContainer
-                )
+                Icon(Icons.Default.Add, contentDescription = "Buat notebook baru", tint = Color.Black)
             }
             Spacer(modifier = Modifier.height(8.dp))
-            Text(
-                "Buat notebook baru",
-                color = MaterialTheme.colorScheme.onSurfaceVariant
-            )
+            Text("Buat notebook baru", color = Color.Black)
         }
     }
 }
@@ -268,9 +250,7 @@ fun NotebookCard(
             .fillMaxWidth()
             .clickable(onClick = onClick),
         shape = RoundedCornerShape(12.dp),
-        colors = CardDefaults.cardColors(
-            containerColor = MaterialTheme.colorScheme.surface
-        )
+        colors = CardDefaults.cardColors(containerColor = Color(0xFFF8F9FA))
     ) {
         Row(
             modifier = Modifier
@@ -283,13 +263,13 @@ fun NotebookCard(
                 modifier = Modifier
                     .size(48.dp)
                     .clip(RoundedCornerShape(8.dp))
-                    .background(MaterialTheme.colorScheme.primaryContainer),
+                    .background(Color(0xFFE8EAF6)),
                 contentAlignment = Alignment.Center
             ) {
                 Icon(
                     Icons.Default.Description,
                     contentDescription = null,
-                    tint = MaterialTheme.colorScheme.onPrimaryContainer
+                    tint = Color(0xFF5C6BC0)
                 )
             }
 
@@ -302,15 +282,14 @@ fun NotebookCard(
                     style = MaterialTheme.typography.titleMedium,
                     fontWeight = FontWeight.Bold,
                     maxLines = 1,
-                    overflow = TextOverflow.Ellipsis,
-                    color = MaterialTheme.colorScheme.onSurface
+                    overflow = TextOverflow.Ellipsis
                 )
                 Spacer(modifier = Modifier.height(4.dp))
                 Text(
                     text = if (notebook.description.isNotBlank()) notebook.description
                     else "Belum ada deskripsi",
                     style = MaterialTheme.typography.bodySmall,
-                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                    color = Color.Gray,
                     maxLines = 1,
                     overflow = TextOverflow.Ellipsis
                 )
@@ -318,7 +297,7 @@ fun NotebookCard(
                 Text(
                     text = dateFormat.format(Date(notebook.updatedAt)),
                     style = MaterialTheme.typography.bodySmall,
-                    color = MaterialTheme.colorScheme.onSurfaceVariant
+                    color = Color.Gray
                 )
             }
 
@@ -327,7 +306,7 @@ fun NotebookCard(
                 Icon(
                     Icons.Default.Delete,
                     contentDescription = "Hapus",
-                    tint = MaterialTheme.colorScheme.onSurfaceVariant
+                    tint = Color.Gray
                 )
             }
         }
@@ -405,7 +384,7 @@ fun SourcesScreen(viewModel: NotebookViewModel) {
     }
 }
 
-// === MENU COMPONENTS ===
+// === MENU COMPONENTS (Tetap sama) ===
 @Composable
 fun AccountScreen(onDismiss: () -> Unit) {
     Dialog(
@@ -456,40 +435,8 @@ fun AccountScreen(onDismiss: () -> Unit) {
 }
 
 @Composable
-fun SettingsMenu(
-    expanded: Boolean,
-    onDismiss: () -> Unit,
-    isDarkMode: Boolean,
-    onThemeChange: (Boolean) -> Unit
-) {
+fun SettingsMenu(expanded: Boolean, onDismiss: () -> Unit) {
     DropdownMenu(expanded = expanded, onDismissRequest = onDismiss) {
-        // Dark Mode Toggle
-        DropdownMenuItem(
-            text = {
-                Row(
-                    modifier = Modifier.fillMaxWidth(),
-                    horizontalArrangement = Arrangement.SpaceBetween,
-                    verticalAlignment = Alignment.CenterVertically
-                ) {
-                    Row(verticalAlignment = Alignment.CenterVertically) {
-                        Icon(
-                            if (isDarkMode) Icons.Default.DarkMode else Icons.Default.LightMode,
-                            contentDescription = null
-                        )
-                        Spacer(modifier = Modifier.width(12.dp))
-                        Text(if (isDarkMode) "Mode Gelap" else "Mode Terang")
-                    }
-                    Switch(
-                        checked = isDarkMode,
-                        onCheckedChange = onThemeChange
-                    )
-                }
-            },
-            onClick = { onThemeChange(!isDarkMode) }
-        )
-
-        Divider()
-
         DropdownMenuItem(
             text = { Text("NotebookLM Help") },
             onClick = { },
@@ -498,3 +445,20 @@ fun SettingsMenu(
     }
 }
 
+@Composable
+fun GoogleAppsMenu(expanded: Boolean, onDismiss: () -> Unit) {
+    val apps = listOf(
+        "Account" to Icons.Default.AccountCircle,
+        "Gmail" to Icons.Default.Mail,
+        "Drive" to Icons.Default.Cloud
+    )
+    DropdownMenu(expanded = expanded, onDismissRequest = onDismiss) {
+        apps.forEach { (name, icon) ->
+            DropdownMenuItem(
+                text = { Text(name) },
+                onClick = { },
+                leadingIcon = { Icon(icon, contentDescription = name) }
+            )
+        }
+    }
+}

app/src/main/java/com/example/notebook/api/ApiConstants.kt

@@ -0,0 +1,30 @@
+package com.example.notebook.api
+
+/**
+ * Constants untuk Gemini API
+ *
+ * PENTING: Jangan commit API key ke Git!
+ * Untuk production, gunakan BuildConfig atau environment variable
+ */
+object ApiConstants {
+
+    // GANTI INI DENGAN API KEY KAMU
+    const val GEMINI_API_KEY = "AIzaSyCVYFUMcKqCDKN5Z_vNwT2Z4VHgjJ5V7dI"
+
+    // Endpoint Gemini API
+    const val BASE_URL = "https://generativelanguage.googleapis.com/"
+
+    // Model yang digunakan (Flash = gratis & cepat)
+    const val MODEL_NAME = "gemini-2.0-flash"
+
+    // System instruction untuk AI
+    const val SYSTEM_INSTRUCTION = """
+        Kamu adalah asisten AI yang membantu pengguna memahami dokumen mereka.
+        Tugasmu:
+        1. Membuat ringkasan yang jelas dan informatif dari dokumen
+        2. Menjawab pertanyaan pengguna berdasarkan isi dokumen
+        3. Selalu rujuk informasi yang ada di dokumen
+        4. Jika informasi tidak ada di dokumen, katakan dengan jelas
+        5. Gunakan bahasa Indonesia yang mudah dipahami
+    """
+}

app/src/main/java/com/example/notebook/api/GeminiApiService.kt

@@ -0,0 +1,48 @@
+package com.example.notebook.api
+
+import okhttp3.OkHttpClient
+import okhttp3.logging.HttpLoggingInterceptor
+import retrofit2.Response
+import retrofit2.Retrofit
+import retrofit2.converter.gson.GsonConverterFactory
+import retrofit2.http.Body
+import retrofit2.http.POST
+import retrofit2.http.Query
+import java.util.concurrent.TimeUnit
+
+/**
+ * Retrofit interface untuk Gemini API
+ */
+interface GeminiApiService {
+
+    @POST("v1beta/models/gemini-2.0-flash:generateContent")
+    suspend fun generateContent(
+        @Query("key") apiKey: String,
+        @Body request: GeminiRequest
+    ): Response<GeminiResponse>
+
+    companion object {
+        fun create(): GeminiApiService {
+            // Logger untuk debug
+            val logger = HttpLoggingInterceptor().apply {
+                level = HttpLoggingInterceptor.Level.BODY
+            }
+
+            // HTTP Client
+            val client = OkHttpClient.Builder()
+                .addInterceptor(logger)
+                .connectTimeout(60, TimeUnit.SECONDS)
+                .readTimeout(60, TimeUnit.SECONDS)
+                .writeTimeout(60, TimeUnit.SECONDS)
+                .build()
+
+            // Retrofit instance
+            return Retrofit.Builder()
+                .baseUrl(ApiConstants.BASE_URL)
+                .client(client)
+                .addConverterFactory(GsonConverterFactory.create())
+                .build()
+                .create(GeminiApiService::class.java)
+        }
+    }
+}

app/src/main/java/com/example/notebook/api/GeminiModels.kt

@@ -0,0 +1,94 @@
+package com.example.notebook.api
+
+import com.google.gson.annotations.SerializedName
+
+/**
+ * Request model untuk Gemini API
+ */
+data class GeminiRequest(
+    @SerializedName("contents")
+    val contents: List<Content>,
+
+    @SerializedName("generationConfig")
+    val generationConfig: GenerationConfig? = null,
+
+    @SerializedName("systemInstruction")
+    val systemInstruction: SystemInstruction? = null
+)
+
+data class Content(
+    @SerializedName("parts")
+    val parts: List<Part>,
+
+    @SerializedName("role")
+    val role: String = "user"
+)
+
+data class Part(
+    @SerializedName("text")
+    val text: String
+)
+
+data class GenerationConfig(
+    @SerializedName("temperature")
+    val temperature: Double = 0.7,
+
+    @SerializedName("maxOutputTokens")
+    val maxOutputTokens: Int = 2048,
+
+    @SerializedName("topP")
+    val topP: Double = 0.95
+)
+
+data class SystemInstruction(
+    @SerializedName("parts")
+    val parts: List<Part>
+)
+
+/**
+ * Response model dari Gemini API
+ */
+data class GeminiResponse(
+    @SerializedName("candidates")
+    val candidates: List<Candidate>?,
+
+    @SerializedName("error")
+    val error: ApiError? = null
+)
+
+data class Candidate(
+    @SerializedName("content")
+    val content: Content,
+
+    @SerializedName("finishReason")
+    val finishReason: String?,
+
+    @SerializedName("safetyRatings")
+    val safetyRatings: List<SafetyRating>?
+)
+
+data class SafetyRating(
+    @SerializedName("category")
+    val category: String,
+
+    @SerializedName("probability")
+    val probability: String
+)
+
+data class ApiError(
+    @SerializedName("code")
+    val code: Int,
+
+    @SerializedName("message")
+    val message: String,
+
+    @SerializedName("status")
+    val status: String
+)
+
+/**
+ * Helper untuk extract text dari response
+ */
+fun GeminiResponse.getTextResponse(): String? {
+    return candidates?.firstOrNull()?.content?.parts?.firstOrNull()?.text
+}

app/src/main/java/com/example/notebook/api/GeminiRepository.kt

@@ -0,0 +1,112 @@
+package com.example.notebook.api
+
+/**
+ * Repository untuk handle Gemini API calls
+ */
+class GeminiRepository {
+
+    private val apiService = GeminiApiService.create()
+
+    /**
+     * Generate summary dari text
+     */
+    suspend fun generateSummary(text: String): Result<String> {
+        return try {
+            val prompt = """
+                Buatlah ringkasan yang komprehensif dari dokumen berikut dalam bahasa Indonesia.
+                Ringkasan harus:
+                - Mencakup poin-poin utama
+                - Mudah dipahami
+                - Panjang sekitar 3-5 paragraf
+                
+                Dokumen:
+                $text
+            """.trimIndent()
+
+            val request = createRequest(prompt)
+            val response = apiService.generateContent(ApiConstants.GEMINI_API_KEY, request)
+
+            if (response.isSuccessful) {
+                val body = response.body()
+                val textResponse = body?.getTextResponse()
+
+                if (textResponse != null) {
+                    Result.success(textResponse)
+                } else {
+                    Result.failure(Exception("Empty response from API"))
+                }
+            } else {
+                Result.failure(Exception("API Error: ${response.code()} - ${response.message()}"))
+            }
+        } catch (e: Exception) {
+            Result.failure(e)
+        }
+    }
+
+    /**
+     * Chat dengan context dokumen
+     */
+    suspend fun chatWithDocument(
+        userMessage: String,
+        documentContext: String,
+        chatHistory: List<Pair<String, String>> = emptyList()
+    ): Result<String> {
+        return try {
+            // Build context dengan chat history
+            val contextBuilder = StringBuilder()
+            contextBuilder.append("Konteks Dokumen:\n$documentContext\n\n")
+
+            if (chatHistory.isNotEmpty()) {
+                contextBuilder.append("Riwayat Chat:\n")
+                chatHistory.forEach { (user, ai) ->
+                    contextBuilder.append("User: $user\n")
+                    contextBuilder.append("AI: $ai\n\n")
+                }
+            }
+
+            contextBuilder.append("Pertanyaan User: $userMessage\n\n")
+            contextBuilder.append("Jawab berdasarkan dokumen di atas. Jika informasi tidak ada di dokumen, katakan dengan jelas.")
+
+            val request = createRequest(contextBuilder.toString())
+            val response = apiService.generateContent(ApiConstants.GEMINI_API_KEY, request)
+
+            if (response.isSuccessful) {
+                val body = response.body()
+                val textResponse = body?.getTextResponse()
+
+                if (textResponse != null) {
+                    Result.success(textResponse)
+                } else {
+                    Result.failure(Exception("Empty response from API"))
+                }
+            } else {
+                val errorBody = response.errorBody()?.string()
+                Result.failure(Exception("API Error: ${response.code()} - $errorBody"))
+            }
+        } catch (e: Exception) {
+            Result.failure(e)
+        }
+    }
+
+    /**
+     * Create request object dengan system instruction
+     */
+    private fun createRequest(prompt: String): GeminiRequest {
+        return GeminiRequest(
+            contents = listOf(
+                Content(
+                    parts = listOf(Part(prompt)),
+                    role = "user"
+                )
+            ),
+            generationConfig = GenerationConfig(
+                temperature = 0.7,
+                maxOutputTokens = 2048,
+                topP = 0.95
+            ),
+            systemInstruction = SystemInstruction(
+                parts = listOf(Part(ApiConstants.SYSTEM_INSTRUCTION.trimIndent()))
+            )
+        )
+    }
+}

app/src/main/java/com/example/notebook/ui/screen/NotebookDetailScreen.kt

@@ -60,9 +60,19 @@ fun NotebookDetailScreen(
 
     // Load notebook data
     LaunchedEffect(notebookId) {
+        println("🚀 NotebookDetailScreen: LaunchedEffect triggered untuk ID: $notebookId")
         viewModel.selectNotebook(notebookId)
     }
 
+    // Debug log untuk state changes
+    LaunchedEffect(notebook) {
+        println("📝 Notebook state updated: ${notebook?.title ?: "NULL"}")
+    }
+
+    LaunchedEffect(sources) {
+        println("📚 Sources updated: ${sources.size} items")
+    }
+
     Scaffold(
         topBar = {
             TopAppBar(
@@ -104,6 +114,18 @@ fun NotebookDetailScreen(
                                 },
                                 leadingIcon = { Icon(Icons.Default.CloudUpload, null) }
                             )
+                            if (sources.isNotEmpty()) {
+                                Divider()
+                                DropdownMenuItem(
+                                    text = { Text("Generate Summary") },
+                                    onClick = {
+                                        viewModel.generateSummary(notebookId)
+                                        selectedTab = 0 // Switch ke chat tab
+                                        showUploadMenu = false
+                                    },
+                                    leadingIcon = { Icon(Icons.Default.Summarize, null) }
+                                )
+                            }
                         }
                     }
                 }

app/src/main/java/com/example/notebook/utils/FileHelper.kt

@@ -76,11 +76,27 @@ object FileHelper {
     }
 
     /**
-     * Baca text dari file
+     * Baca text dari file (support Text, Markdown, dan PDF)
      */
     fun readTextFromFile(filePath: String): String? {
         return try {
-            File(filePath).readText()
+            val file = File(filePath)
+            val extension = file.extension.lowercase()
+
+            when (extension) {
+                "pdf" -> {
+                    // Extract text dari PDF
+                    PdfHelper.extractTextFromPdf(filePath)
+                }
+                "txt", "md", "markdown" -> {
+                    // Baca text biasa
+                    file.readText()
+                }
+                else -> {
+                    println("⚠️ Format file tidak didukung untuk ekstraksi teks: $extension")
+                    null
+                }
+            }
         } catch (e: Exception) {
             e.printStackTrace()
             null

app/src/main/java/com/example/notebook/utils/PdfHelper.kt

@@ -0,0 +1,93 @@
+package com.example.notebook.utils
+
+import android.content.Context
+import android.net.Uri
+import com.tom_roush.pdfbox.android.PDFBoxResourceLoader
+import com.tom_roush.pdfbox.pdmodel.PDDocument
+import com.tom_roush.pdfbox.text.PDFTextStripper
+import java.io.File
+
+/**
+ * Helper untuk extract text dari PDF
+ */
+object PdfHelper {
+
+    /**
+     * Initialize PDFBox (panggil sekali saat app start)
+     */
+    fun initialize(context: Context) {
+        PDFBoxResourceLoader.init(context)
+    }
+
+    /**
+     * Extract text dari PDF file
+     * Return: Text content atau null jika error
+     */
+    fun extractTextFromPdf(filePath: String): String? {
+        return try {
+            val file = File(filePath)
+            val document = PDDocument.load(file)
+
+            val stripper = PDFTextStripper()
+            val text = stripper.getText(document)
+
+            document.close()
+
+            // Cleanup whitespace
+            text.trim()
+        } catch (e: Exception) {
+            println("❌ Error extract PDF: ${e.message}")
+            e.printStackTrace()
+            null
+        }
+    }
+
+    /**
+     * Extract text dari PDF URI (sebelum disimpan)
+     */
+    fun extractTextFromPdfUri(context: Context, uri: Uri): String? {
+        return try {
+            val inputStream = context.contentResolver.openInputStream(uri)
+            val document = PDDocument.load(inputStream)
+
+            val stripper = PDFTextStripper()
+            val text = stripper.getText(document)
+
+            document.close()
+            inputStream?.close()
+
+            text.trim()
+        } catch (e: Exception) {
+            println("❌ Error extract PDF from URI: ${e.message}")
+            e.printStackTrace()
+            null
+        }
+    }
+
+    /**
+     * Get info PDF (jumlah halaman, dll)
+     */
+    fun getPdfInfo(filePath: String): PdfInfo? {
+        return try {
+            val file = File(filePath)
+            val document = PDDocument.load(file)
+
+            val info = PdfInfo(
+                pageCount = document.numberOfPages,
+                title = document.documentInformation.title ?: "Unknown",
+                author = document.documentInformation.author ?: "Unknown"
+            )
+
+            document.close()
+            info
+        } catch (e: Exception) {
+            null
+        }
+    }
+}
+
+data class PdfInfo(
+    val pageCount: Int,
+    val title: String,
+    val author: String
+)

app/src/main/java/com/example/notebook/viewmodel/NotebookViewModel.kt

@@ -3,6 +3,7 @@ package com.example.notebook.viewmodel
 import android.app.Application
 import androidx.lifecycle.AndroidViewModel
 import androidx.lifecycle.viewModelScope
+import com.example.notebook.api.GeminiRepository
 import com.example.notebook.data.AppDatabase
 import com.example.notebook.data.NotebookEntity
 import com.example.notebook.data.NotebookRepository
@@ -20,6 +21,7 @@ import kotlinx.coroutines.launch
 class NotebookViewModel(application: Application) : AndroidViewModel(application) {
 
     private val repository: NotebookRepository
+    private val geminiRepository = GeminiRepository()
 
     // State untuk list notebooks
     private val _notebooks = MutableStateFlow<List<NotebookEntity>>(emptyList())
@@ -41,6 +43,10 @@ class NotebookViewModel(application: Application) : AndroidViewModel(application
     private val _isLoading = MutableStateFlow(false)
     val isLoading: StateFlow<Boolean> = _isLoading.asStateFlow()
 
+    // State error
+    private val _errorMessage = MutableStateFlow<String?>(null)
+    val errorMessage: StateFlow<String?> = _errorMessage.asStateFlow()
+
     init {
         val database = AppDatabase.getDatabase(application)
         repository = NotebookRepository(database.notebookDao())
@@ -49,9 +55,6 @@ class NotebookViewModel(application: Application) : AndroidViewModel(application
 
     // === NOTEBOOK FUNCTIONS ===
 
-    /**
-     * Load semua notebooks dari database
-     */
     private fun loadNotebooks() {
         viewModelScope.launch {
             repository.getAllNotebooks().collect { notebooks ->
@@ -60,15 +63,11 @@ class NotebookViewModel(application: Application) : AndroidViewModel(application
         }
     }
 
-    /**
-     * Buat notebook baru
-     */
     fun createNotebook(title: String, description: String = "") {
         viewModelScope.launch {
             _isLoading.value = true
             try {
                 val notebookId = repository.createNotebook(title, description)
-                // Otomatis ter-update karena Flow
                 println("✅ Notebook berhasil dibuat dengan ID: $notebookId")
             } catch (e: Exception) {
                 println("❌ Error membuat notebook: ${e.message}")
@@ -78,33 +77,28 @@ class NotebookViewModel(application: Application) : AndroidViewModel(application
         }
     }
 
-    /**
-     * Pilih notebook untuk dibuka
-     */
     fun selectNotebook(notebookId: Int) {
+        println("📂 selectNotebook dipanggil dengan ID: $notebookId")
         viewModelScope.launch {
             repository.getNotebookById(notebookId).collect { notebook ->
+                println("📖 Notebook data: ${notebook?.title ?: "NULL"}")
                 _currentNotebook.value = notebook
                 notebook?.let {
+                    println("📦 Loading sources untuk notebook ID: $notebookId")
                     loadSources(notebookId)
+                    println("💬 Loading chat history untuk notebook ID: $notebookId")
                     loadChatHistory(notebookId)
                 }
             }
         }
     }
 
-    /**
-     * Update notebook
-     */
     fun updateNotebook(notebook: NotebookEntity) {
         viewModelScope.launch {
             repository.updateNotebook(notebook)
         }
     }
 
-    /**
-     * Hapus notebook
-     */
     fun deleteNotebook(notebook: NotebookEntity) {
         viewModelScope.launch {
             repository.deleteNotebook(notebook)
@@ -113,9 +107,6 @@ class NotebookViewModel(application: Application) : AndroidViewModel(application
 
     // === SOURCE FUNCTIONS ===
 
-    /**
-     * Load sources untuk notebook tertentu
-     */
     private fun loadSources(notebookId: Int) {
         viewModelScope.launch {
             repository.getSourcesByNotebook(notebookId).collect { sources ->
@@ -124,9 +115,6 @@ class NotebookViewModel(application: Application) : AndroidViewModel(application
         }
     }
 
-    /**
-     * Tambah source baru
-     */
     fun addSource(
         notebookId: Int,
         fileName: String,
@@ -146,9 +134,6 @@ class NotebookViewModel(application: Application) : AndroidViewModel(application
         }
     }
 
-    /**
-     * Handle file upload dari URI
-     */
     fun uploadFile(context: android.content.Context, uri: android.net.Uri, notebookId: Int) {
         viewModelScope.launch {
             _isLoading.value = true
@@ -171,15 +156,11 @@ class NotebookViewModel(application: Application) : AndroidViewModel(application
         }
     }
 
-    /**
-     * Hapus source
-     */
-    fun deleteSource(source: com.example.notebook.data.SourceEntity) {
+    fun deleteSource(source: SourceEntity) {
         viewModelScope.launch {
             _isLoading.value = true
             try {
                 repository.deleteSource(source)
-                // Hapus file fisik juga
                 com.example.notebook.utils.FileHelper.deleteFile(source.filePath)
                 println("✅ Source berhasil dihapus: ${source.fileName}")
             } catch (e: Exception) {
@@ -192,9 +173,6 @@ class NotebookViewModel(application: Application) : AndroidViewModel(application
 
     // === CHAT FUNCTIONS ===
 
-    /**
-     * Load chat history
-     */
     private fun loadChatHistory(notebookId: Int) {
         viewModelScope.launch {
             repository.getChatHistory(notebookId).collect { messages ->
@@ -203,36 +181,126 @@ class NotebookViewModel(application: Application) : AndroidViewModel(application
         }
     }
 
-    /**
-     * Kirim pesan user
-     */
     fun sendUserMessage(notebookId: Int, message: String) {
         viewModelScope.launch {
+            _isLoading.value = true
+            try {
                 repository.sendMessage(notebookId, message, isUserMessage = true)
-            // TODO: Panggil Gemini API di sini
-            // Sementara kirim dummy AI response
-            simulateAIResponse(notebookId, message)
+
+                val documentContext = buildDocumentContext()
+
+                if (documentContext.isEmpty()) {
+                    val reply = "Maaf, belum ada dokumen yang diupload. Silakan upload dokumen terlebih dahulu untuk bisa bertanya."
+                    repository.sendMessage(notebookId, reply, isUserMessage = false)
+                } else {
+                    val chatHistory = _chatMessages.value
+                        .takeLast(10)
+                        .filter { it.isUserMessage }
+                        .mapNotNull { userMsg ->
+                            val aiMsg = _chatMessages.value.find {
+                                !it.isUserMessage && it.timestamp > userMsg.timestamp
                             }
+                            if (aiMsg != null) {
+                                Pair(userMsg.message, aiMsg.message)
+                            } else null
                         }
 
-    /**
-     * Simulasi AI response (sementara sebelum Gemini API)
-     */
-    private fun simulateAIResponse(notebookId: Int, userMessage: String) {
-        viewModelScope.launch {
-            // Delay simulasi "AI thinking"
-            kotlinx.coroutines.delay(1000)
-            val aiResponse = "Ini adalah response sementara untuk: \"$userMessage\""
+                    val result = geminiRepository.chatWithDocument(
+                        userMessage = message,
+                        documentContext = documentContext,
+                        chatHistory = chatHistory
+                    )
+
+                    result.fold(
+                        onSuccess = { aiResponse ->
                             repository.sendMessage(notebookId, aiResponse, isUserMessage = false)
+                            println("✅ AI response berhasil: ${aiResponse.take(50)}...")
+                        },
+                        onFailure = { error ->
+                            val errorMsg = "Maaf, terjadi error: ${error.message}"
+                            repository.sendMessage(notebookId, errorMsg, isUserMessage = false)
+                            println("❌ Error dari Gemini: ${error.message}")
+                            _errorMessage.value = error.message
+                        }
+                    )
+                }
+            } catch (e: Exception) {
+                println("❌ Error mengirim pesan: ${e.message}")
+                _errorMessage.value = e.message
+            } finally {
+                _isLoading.value = false
+            }
         }
     }
 
-    /**
-     * Clear chat history
-     */
     fun clearChatHistory(notebookId: Int) {
         viewModelScope.launch {
             repository.clearChatHistory(notebookId)
         }
     }
+
+    // === GEMINI FUNCTIONS ===
+
+    private fun buildDocumentContext(): String {
+        val context = StringBuilder()
+
+        _sources.value.forEach { source ->
+            when (source.fileType) {
+                "Text", "Markdown" -> {
+                    val content = com.example.notebook.utils.FileHelper.readTextFromFile(source.filePath)
+                    if (content != null) {
+                        context.append("=== ${source.fileName} ===\n")
+                        context.append(content)
+                        context.append("\n\n")
+                    }
+                }
+                else -> {
+                    context.append("=== ${source.fileName} ===\n")
+                    context.append("[File type ${source.fileType} - content extraction not yet supported]\n\n")
+                }
+            }
+        }
+
+        return context.toString()
+    }
+
+    fun generateSummary(notebookId: Int) {
+        viewModelScope.launch {
+            _isLoading.value = true
+            try {
+                val documentContext = buildDocumentContext()
+
+                if (documentContext.isEmpty()) {
+                    _errorMessage.value = "Tidak ada dokumen untuk diringkas"
+                    return@launch
+                }
+
+                val result = geminiRepository.generateSummary(documentContext)
+
+                result.fold(
+                    onSuccess = { summary ->
+                        repository.sendMessage(
+                            notebookId,
+                            "📝 Ringkasan Dokumen:\n\n$summary",
+                            isUserMessage = false
+                        )
+                        println("✅ Summary berhasil: ${summary.take(100)}...")
+                    },
+                    onFailure = { error ->
+                        _errorMessage.value = "Error generate summary: ${error.message}"
+                        println("❌ Error generate summary: ${error.message}")
+                    }
+                )
+            } catch (e: Exception) {
+                _errorMessage.value = e.message
+                println("❌ Error: ${e.message}")
+            } finally {
+                _isLoading.value = false
+            }
+        }
+    }
+
+    fun clearError() {
+        _errorMessage.value = null
+    }
 }