feat: Add password dialog for enabling biometric authentication in ProfileScreen

app/src/main/java/com/rosetta/messenger/ui/settings/ProfileScreen.kt

@@ -161,6 +161,9 @@ fun ProfileScreen(
     // Biometric state
     var biometricAvailable by remember { mutableStateOf<BiometricAvailability>(BiometricAvailability.NotAvailable("Checking...")) }
     var isBiometricEnabled by remember { mutableStateOf(false) }
+    var showPasswordDialog by remember { mutableStateOf(false) }
+    var passwordInput by remember { mutableStateOf("") }
+    var passwordError by remember { mutableStateOf<String?>(null) }
     
     // Check biometric availability
     LaunchedEffect(Unit) {
@@ -430,9 +433,9 @@ fun ProfileScreen(
                     TelegramBiometricItem(
                         isEnabled = isBiometricEnabled,
                         onToggle = {
-                            scope.launch {
+                            if (isBiometricEnabled) {
-                                if (isBiometricEnabled) {
+                                // Disable biometric
-                                    // Disable biometric
+                                scope.launch {
                                     biometricPrefs.disableBiometric()
                                     biometricPrefs.removeEncryptedPassword(accountPublicKey)
                                     isBiometricEnabled = false
@@ -441,16 +444,12 @@ fun ProfileScreen(
                                         "Biometric authentication disabled",
                                         android.widget.Toast.LENGTH_SHORT
                                     ).show()
-                                } else {
-                                    // Enable biometric
-                                    biometricPrefs.enableBiometric()
-                                    isBiometricEnabled = true
-                                    android.widget.Toast.makeText(
-                                        context,
-                                        "Biometric authentication enabled. Your password will be securely saved on next unlock.",
-                                        android.widget.Toast.LENGTH_LONG
-                                    ).show()
                                 }
+                            } else {
+                                // Enable biometric - show password dialog first
+                                passwordInput = ""
+                                passwordError = null
+                                showPasswordDialog = true
                             }
                         },
                         isDarkTheme = isDarkTheme
@@ -504,6 +503,100 @@ fun ProfileScreen(
             avatarRepository = avatarRepository
         )
     }
+    
+    // Password dialog for biometric setup
+    if (showPasswordDialog && activity != null) {
+        AlertDialog(
+            onDismissRequest = {
+                showPasswordDialog = false
+                passwordInput = ""
+                passwordError = null
+            },
+            title = { Text("Enable Biometric Authentication") },
+            text = {
+                Column {
+                    Text("Enter your password to securely save it for biometric unlock:")
+                    Spacer(modifier = Modifier.height(16.dp))
+                    OutlinedTextField(
+                        value = passwordInput,
+                        onValueChange = {
+                            passwordInput = it
+                            passwordError = null
+                        },
+                        label = { Text("Password") },
+                        singleLine = true,
+                        visualTransformation = androidx.compose.ui.text.input.PasswordVisualTransformation(),
+                        isError = passwordError != null,
+                        modifier = Modifier.fillMaxWidth()
+                    )
+                    if (passwordError != null) {
+                        Spacer(modifier = Modifier.height(4.dp))
+                        Text(
+                            text = passwordError!!,
+                            color = Color.Red,
+                            fontSize = 12.sp
+                        )
+                    }
+                }
+            },
+            confirmButton = {
+                TextButton(
+                    onClick = {
+                        if (passwordInput.isEmpty()) {
+                            passwordError = "Password cannot be empty"
+                            return@TextButton
+                        }
+                        
+                        // Try to encrypt the password with biometric
+                        biometricManager.encryptPassword(
+                            activity = activity,
+                            password = passwordInput,
+                            onSuccess = { encryptedPassword ->
+                                scope.launch {
+                                    // Save encrypted password
+                                    biometricPrefs.saveEncryptedPassword(accountPublicKey, encryptedPassword)
+                                    // Enable biometric
+                                    biometricPrefs.enableBiometric()
+                                    isBiometricEnabled = true
+                                    
+                                    showPasswordDialog = false
+                                    passwordInput = ""
+                                    passwordError = null
+                                    
+                                    android.widget.Toast.makeText(
+                                        context,
+                                        "Biometric authentication enabled successfully",
+                                        android.widget.Toast.LENGTH_SHORT
+                                    ).show()
+                                }
+                            },
+                            onError = { error ->
+                                passwordError = error
+                            },
+                            onCancel = {
+                                showPasswordDialog = false
+                                passwordInput = ""
+                                passwordError = null
+                            }
+                        )
+                    }
+                ) {
+                    Text("Enable")
+                }
+            },
+            dismissButton = {
+                TextButton(
+                    onClick = {
+                        showPasswordDialog = false
+                        passwordInput = ""
+                        passwordError = null
+                    }
+                ) {
+                    Text("Cancel")
+                }
+            }
+        )
+    }
 }
 
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