feat: Implement message encryption in database to enhance security

app/src/main/java/com/rosetta/messenger/ui/chats/ChatViewModel.kt

@@ -978,18 +978,23 @@ class ChatViewModel(application: Application) : AndroidViewModel(application) {
     
     /**
      * Сохранить диалог в базу данных
+     * 🔒 lastMessage шифруется для безопасного хранения
      */
     private suspend fun saveDialog(lastMessage: String, timestamp: Long) {
         val account = myPublicKey ?: return
         val opponent = opponentKey ?: return
+        val privateKey = myPrivateKey ?: return
         
         try {
-            ProtocolManager.addLog("💾 Saving dialog: ${lastMessage.take(20)}...")
+            // 🔒 Шифруем lastMessage перед сохранением
+            val encryptedLastMessage = CryptoManager.encryptWithPassword(lastMessage, privateKey)
+            
+            ProtocolManager.addLog("💾 Saving dialog: ${lastMessage.take(20)}... (encrypted)")
             val existingDialog = dialogDao.getDialog(account, opponent)
             
             if (existingDialog != null) {
                 // Обновляем последнее сообщение
-                dialogDao.updateLastMessage(account, opponent, lastMessage, timestamp)
+                dialogDao.updateLastMessage(account, opponent, encryptedLastMessage, timestamp)
                 ProtocolManager.addLog("✅ Dialog updated (existing)")
             } else {
                 // Создаём новый диалог
@@ -998,7 +1003,7 @@ class ChatViewModel(application: Application) : AndroidViewModel(application) {
                     opponentKey = opponent,
                     opponentTitle = opponentTitle,
                     opponentUsername = opponentUsername,
-                    lastMessage = lastMessage,
+                    lastMessage = encryptedLastMessage,
                     lastMessageTimestamp = timestamp
                 ))
                 ProtocolManager.addLog("✅ Dialog created (new)")
@@ -1014,13 +1019,17 @@ class ChatViewModel(application: Application) : AndroidViewModel(application) {
      */
     private suspend fun updateDialog(opponentKey: String, lastMessage: String, timestamp: Long, incrementUnread: Boolean) {
         val account = myPublicKey ?: return
+        val privateKey = myPrivateKey ?: return
         
         try {
+            // 🔒 Шифруем lastMessage для диалога
+            val encryptedLastMessage = CryptoManager.encryptWithPassword(lastMessage, privateKey)
+            
             val existingDialog = dialogDao.getDialog(account, opponentKey)
             
             if (existingDialog != null) {
                 // Обновляем последнее сообщение
-                dialogDao.updateLastMessage(account, opponentKey, lastMessage, timestamp)
+                dialogDao.updateLastMessage(account, opponentKey, encryptedLastMessage, timestamp)
                 
                 // Инкрементируем непрочитанные если нужно
                 if (incrementUnread) {
@@ -1035,7 +1044,7 @@ class ChatViewModel(application: Application) : AndroidViewModel(application) {
                     opponentKey = opponentKey,
                     opponentTitle = opponentTitle,
                     opponentUsername = opponentUsername,
-                    lastMessage = lastMessage,
+                    lastMessage = encryptedLastMessage,  // 🔒 Зашифрованный
                     lastMessageTimestamp = timestamp,
                     unreadCount = if (incrementUnread) 1 else 0
                 ))
@@ -1066,7 +1075,7 @@ class ChatViewModel(application: Application) : AndroidViewModel(application) {
     ) {
         val account = myPublicKey ?: return
         val opponent = opponentPublicKey ?: opponentKey ?: return
-        val privateKey = this.privateKey ?: return
+        val privateKey = myPrivateKey ?: return
         
         try {
             val dialogKey = getDialogKey(account, opponent)

app/src/main/java/com/rosetta/messenger/ui/chats/ChatsListScreen.kt

@@ -30,7 +30,7 @@ import androidx.compose.ui.unit.sp
 import com.airbnb.lottie.compose.*
 import com.rosetta.messenger.R
 import com.rosetta.messenger.data.RecentSearchesManager
-import com.rosetta.messenger.database.DialogEntity
+import com.rosetta.messenger.database.RosettaDatabase
 import com.rosetta.messenger.network.ProtocolManager
 import com.rosetta.messenger.network.ProtocolState
 import com.rosetta.messenger.ui.components.AppleEmojiText
@@ -126,6 +126,7 @@ fun ChatsListScreen(
         accountName: String,
         accountPhone: String,
         accountPublicKey: String,
+        accountPrivateKey: String = "",
         privateKeyHash: String = "",
         onToggleTheme: () -> Unit,
         onProfileClick: () -> Unit,
@@ -182,9 +183,9 @@ fun ChatsListScreen(
     val dialogsList by chatsViewModel.dialogs.collectAsState()
 
     // Load dialogs when account is available
-    LaunchedEffect(accountPublicKey) {
-        if (accountPublicKey.isNotEmpty()) {
-            chatsViewModel.setAccount(accountPublicKey)
+    LaunchedEffect(accountPublicKey, accountPrivateKey) {
+        if (accountPublicKey.isNotEmpty() && accountPrivateKey.isNotEmpty()) {
+            chatsViewModel.setAccount(accountPublicKey, accountPrivateKey)
             // Устанавливаем аккаунт для RecentSearchesManager
             RecentSearchesManager.setAccount(accountPublicKey)
         }
@@ -783,7 +784,7 @@ fun DrawerMenuItem(
 
 /** Элемент диалога из базы данных - ОПТИМИЗИРОВАННЫЙ */
 @Composable
-fun DialogItem(dialog: DialogEntity, isDarkTheme: Boolean, onClick: () -> Unit) {
+fun DialogItem(dialog: DialogUiModel, isDarkTheme: Boolean, onClick: () -> Unit) {
     // 🔥 ОПТИМИЗАЦИЯ: Кешируем цвета и строки
     val textColor = remember(isDarkTheme) { if (isDarkTheme) Color.White else Color.Black }
     val secondaryTextColor = remember(isDarkTheme) { if (isDarkTheme) Color(0xFF8E8E93) else Color(0xFF666666) }

app/src/main/java/com/rosetta/messenger/ui/chats/ChatsListViewModel.kt

@@ -3,6 +3,7 @@ package com.rosetta.messenger.ui.chats
 import android.app.Application
 import androidx.lifecycle.AndroidViewModel
 import androidx.lifecycle.viewModelScope
+import com.rosetta.messenger.crypto.CryptoManager
 import com.rosetta.messenger.database.DialogEntity
 import com.rosetta.messenger.database.RosettaDatabase
 import com.rosetta.messenger.network.ProtocolManager
@@ -10,9 +11,26 @@ import com.rosetta.messenger.network.SearchUser
 import kotlinx.coroutines.flow.*
 import kotlinx.coroutines.launch
 
+/**
+ * UI модель диалога с расшифрованным lastMessage
+ */
+data class DialogUiModel(
+    val id: Long,
+    val account: String,
+    val opponentKey: String,
+    val opponentTitle: String,
+    val opponentUsername: String,
+    val lastMessage: String,  // 🔓 Расшифрованный текст
+    val lastMessageTimestamp: Long,
+    val unreadCount: Int,
+    val isOnline: Int,
+    val lastSeen: Long,
+    val verified: Int
+)
+
 /**
  * ViewModel для списка чатов
- * Загружает диалоги из базы данных
+ * Загружает диалоги из базы данных и расшифровывает lastMessage
  */
 class ChatsListViewModel(application: Application) : AndroidViewModel(application) {
     
@@ -20,10 +38,11 @@ class ChatsListViewModel(application: Application) : AndroidViewModel(applicatio
     private val dialogDao = database.dialogDao()
     
     private var currentAccount: String = ""
+    private var currentPrivateKey: String? = null
     
-    // Список диалогов из базы
-    private val _dialogs = MutableStateFlow<List<DialogEntity>>(emptyList())
-    val dialogs: StateFlow<List<DialogEntity>> = _dialogs.asStateFlow()
+    // Список диалогов с расшифрованными сообщениями
+    private val _dialogs = MutableStateFlow<List<DialogUiModel>>(emptyList())
+    val dialogs: StateFlow<List<DialogUiModel>> = _dialogs.asStateFlow()
     
     // Загрузка
     private val _isLoading = MutableStateFlow(false)
@@ -32,15 +51,44 @@ class ChatsListViewModel(application: Application) : AndroidViewModel(applicatio
     /**
      * Установить текущий аккаунт и загрузить диалоги
      */
-    fun setAccount(publicKey: String) {
+    fun setAccount(publicKey: String, privateKey: String) {
         if (currentAccount == publicKey) return
         currentAccount = publicKey
+        currentPrivateKey = privateKey
         
         viewModelScope.launch {
             dialogDao.getDialogsFlow(publicKey)
                 .collect { dialogsList ->
-                    _dialogs.value = dialogsList
-                    ProtocolManager.addLog("📋 Dialogs loaded: ${dialogsList.size}")
+                    // 🔓 Расшифровываем lastMessage для каждого диалога
+                    val decryptedDialogs = dialogsList.map { dialog ->
+                        val decryptedLastMessage = try {
+                            if (privateKey.isNotEmpty() && dialog.lastMessage.isNotEmpty()) {
+                                CryptoManager.decryptWithPassword(dialog.lastMessage, privateKey)
+                                    ?: dialog.lastMessage
+                            } else {
+                                dialog.lastMessage
+                            }
+                        } catch (e: Exception) {
+                            dialog.lastMessage  // Fallback на зашифрованный текст
+                        }
+                        
+                        DialogUiModel(
+                            id = dialog.id,
+                            account = dialog.account,
+                            opponentKey = dialog.opponentKey,
+                            opponentTitle = dialog.opponentTitle,
+                            opponentUsername = dialog.opponentUsername,
+                            lastMessage = decryptedLastMessage,
+                            lastMessageTimestamp = dialog.lastMessageTimestamp,
+                            unreadCount = dialog.unreadCount,
+                            isOnline = dialog.isOnline,
+                            lastSeen = dialog.lastSeen,
+                            verified = dialog.verified
+                        )
+                    }
+                    
+                    _dialogs.value = decryptedDialogs
+                    ProtocolManager.addLog("📋 Dialogs loaded: ${decryptedDialogs.size} (lastMessages decrypted)")
                 }
         }
     }
@@ -58,12 +106,16 @@ class ChatsListViewModel(application: Application) : AndroidViewModel(applicatio
         isOnline: Int = 0
     ) {
         if (currentAccount.isEmpty()) return
+        val privateKey = currentPrivateKey ?: return
+        
+        // 🔒 Шифруем lastMessage перед сохранением
+        val encryptedLastMessage = CryptoManager.encryptWithPassword(lastMessage, privateKey)
         
         val existingDialog = dialogDao.getDialog(currentAccount, opponentKey)
         
         if (existingDialog != null) {
             // Обновляем
-            dialogDao.updateLastMessage(currentAccount, opponentKey, lastMessage, timestamp)
+            dialogDao.updateLastMessage(currentAccount, opponentKey, encryptedLastMessage, timestamp)
             if (opponentTitle.isNotEmpty()) {
                 dialogDao.updateOpponentInfo(currentAccount, opponentKey, opponentTitle, opponentUsername, verified)
             }
@@ -74,7 +126,7 @@ class ChatsListViewModel(application: Application) : AndroidViewModel(applicatio
                 opponentKey = opponentKey,
                 opponentTitle = opponentTitle,
                 opponentUsername = opponentUsername,
-                lastMessage = lastMessage,
+                lastMessage = encryptedLastMessage,  // 🔒 Зашифрованный
                 lastMessageTimestamp = timestamp,
                 verified = verified,
                 isOnline = isOnline
@@ -83,9 +135,9 @@ class ChatsListViewModel(application: Application) : AndroidViewModel(applicatio
     }
     
     /**
-     * Конвертировать DialogEntity в SearchUser для навигации
+     * Конвертировать DialogUiModel в SearchUser для навигации
      */
-    fun dialogToSearchUser(dialog: DialogEntity): SearchUser {
+    fun dialogToSearchUser(dialog: DialogUiModel): SearchUser {
         return SearchUser(
             title = dialog.opponentTitle,
             username = dialog.opponentUsername,