enable support for incognito keyboard

- issue: #22

Signed-off-by: Keshav Priyadarshi <git@keshav.space>

lib/data/preference_and_config.dart

@@ -1,12 +1,13 @@
 // Package imports:
 import 'package:shared_preferences/shared_preferences.dart';
 
-class AppSecurePreferencesStorage {
+class PreferencesStorage {
   static SharedPreferences? _preferences;
 
   static const _keyPassPhraseHash = 'passphrasehash';
   static const _keyAllowUndecryptLoginFlag = 'undecryptLoginFlag';
   static const _keyIsThemeDark = 'isthemedark';
+  static const _keyKeyboardIncognito = 'keyboardIcognito';
 
   static Future init() async =>
       _preferences = await SharedPreferences.getInstance();
@@ -19,18 +20,21 @@ class AppSecurePreferencesStorage {
   static Future setAllowUndecryptLoginFlag(bool flag) async =>
       await _preferences?.setBool(_keyAllowUndecryptLoginFlag, flag);
   static bool getAllowUndecryptLoginFlag() {
-    bool? localFlag = _preferences?.getBool(_keyAllowUndecryptLoginFlag);
-    localFlag ??= true;
-    return localFlag;
+    return _preferences?.getBool(_keyAllowUndecryptLoginFlag) ?? true;
   }
 
   static Future setIsThemeDark(bool flag) async =>
       await _preferences?.setBool(_keyIsThemeDark, flag);
 
   static bool getIsThemeDark() {
-    bool? localFlag = _preferences?.getBool(_keyIsThemeDark);
-    localFlag ??= true;
-    return localFlag;
+    return _preferences?.getBool(_keyIsThemeDark) ?? true;
+  }
+
+  static Future<void> setKeyboardIncognito(bool flag) async =>
+      await _preferences?.setBool(_keyKeyboardIncognito, flag);
+
+  static bool getKeyboardIncognito() {
+    return _preferences?.getBool(_keyKeyboardIncognito) ?? true;
   }
 }
 
@@ -44,7 +48,7 @@ class PhraseHandler {
 
 class UnDecryptedLoginControl {
   static getAllowLogUnDecrypted() =>
-      AppSecurePreferencesStorage.getAllowUndecryptLoginFlag();
+      PreferencesStorage.getAllowUndecryptLoginFlag();
 
   static bool noDecryptionFlag = false;
   static setNoDecryptionFlag(bool flag) => noDecryptionFlag = flag;

lib/dialogs/change_passphrase.dart

@@ -124,7 +124,7 @@ class _ChangePassphraseDialogState extends State<ChangePassphraseDialog> {
       },
       validator: (passphrase) {
         return sha256.convert(utf8.encode(passphrase!)).toString() !=
-                AppSecurePreferencesStorage.getPassPhraseHash()
+                PreferencesStorage.getPassPhraseHash()
             ? validationErrorMsg
             : null;
       },
@@ -272,7 +272,7 @@ class _ChangePassphraseDialogState extends State<ChangePassphraseDialog> {
 
     // Update SHA256 signature of passphrase
     if (form.validate()) {
-      AppSecurePreferencesStorage.setPassPhraseHash(
+      PreferencesStorage.setPassPhraseHash(
         sha256
             .convert(utf8.encode(_newConfirmPassphraseController.text))
             .toString(),

lib/dialogs/toggle_undecrypt_flag.dart

@@ -17,8 +17,8 @@ class ToggleUndecryptionFlag extends StatefulWidget {
 
 class _ToggleUndecryptionFlagState extends State<ToggleUndecryptionFlag> {
   List<bool> _isSelected = [
-    AppSecurePreferencesStorage.getAllowUndecryptLoginFlag(),
-    !AppSecurePreferencesStorage.getAllowUndecryptLoginFlag()
+    PreferencesStorage.getAllowUndecryptLoginFlag(),
+    !PreferencesStorage.getAllowUndecryptLoginFlag()
   ];
 
   @override
@@ -121,10 +121,10 @@ Once ON, You'll need to choose the second option on the login screen to see your
         //color: Colors.black,
         color: Colors.grey,
         fillColor: Colors.lightBlue.shade900,
-        borderColor: AppSecurePreferencesStorage.getIsThemeDark()
+        borderColor: PreferencesStorage.getIsThemeDark()
             ? NordColors.snowStorm.darkest
             : Colors.grey.withOpacity(0.8),
-        selectedBorderColor: AppSecurePreferencesStorage.getIsThemeDark()
+        selectedBorderColor: PreferencesStorage.getIsThemeDark()
             ? NordColors.snowStorm.darkest
             : Colors.grey.withOpacity(0.8),
         borderRadius: BorderRadius.circular(5),
@@ -163,8 +163,7 @@ Once ON, You'll need to choose the second option on the login screen to see your
         this._isSelected[0] = false;
         this._isSelected[1] = true;
       }
-      AppSecurePreferencesStorage.setAllowUndecryptLoginFlag(
-          this._isSelected[0]);
+      PreferencesStorage.setAllowUndecryptLoginFlag(this._isSelected[0]);
     });
   }
 }

lib/main.dart

@@ -17,7 +17,7 @@ Future main() async {
     DeviceOrientation.portraitUp,
     DeviceOrientation.portraitDown,
   ]);
-  await AppSecurePreferencesStorage.init();
+  await PreferencesStorage.init();
   runApp(SafeNotesApp());
 }
 
@@ -36,7 +36,7 @@ class SafeNotesApp extends StatelessWidget {
           theme: AppThemes.lightTheme,
           darkTheme: AppThemes.darkTheme,
 
-          home: AppSecurePreferencesStorage.getPassPhraseHash() != null
+          home: PreferencesStorage.getPassPhraseHash() != null
               ? EncryptionPhraseLoginPage()
               : SetEncryptionPhrasePage(),
         );

lib/models/app_theme.dart

@@ -8,14 +8,13 @@ import 'package:flutter_nord_theme/flutter_nord_theme.dart';
 import 'package:safenotes/data/preference_and_config.dart';
 
 class ThemeProvider extends ChangeNotifier {
-  ThemeMode themeMode = AppSecurePreferencesStorage.getIsThemeDark()
-      ? ThemeMode.dark
-      : ThemeMode.light;
+  ThemeMode themeMode =
+      PreferencesStorage.getIsThemeDark() ? ThemeMode.dark : ThemeMode.light;
 
   bool get isDarkMode => themeMode == ThemeMode.dark;
   void toggleTheme(bool isOn) {
     themeMode = isOn ? ThemeMode.dark : ThemeMode.light;
-    AppSecurePreferencesStorage.setIsThemeDark(isOn);
+    PreferencesStorage.setIsThemeDark(isOn);
     notifyListeners();
   }
 }

lib/models/file_handler.dart

@@ -25,8 +25,7 @@ class FileHandler {
     String fileName = AppInfo.getExportFileName();
     final bool isExportEncrypted =
         ExportEncryptionControl.getIsExportEncrypted();
-    final String passHash =
-        AppSecurePreferencesStorage.getPassPhraseHash().toString();
+    final String passHash = PreferencesStorage.getPassPhraseHash().toString();
 
     String preFixToRecord = '{ "records" : ';
     String postFixToRecord = ', "recordHandlerHash" : ' +
@@ -77,7 +76,7 @@ class FileHandler {
 
   Future<String?> selectFileAndDoImport(BuildContext context) async {
     String? dataFromFileAsString = await getFileAsString();
-    String? currentPassHash = AppSecurePreferencesStorage.getPassPhraseHash();
+    String? currentPassHash = PreferencesStorage.getPassPhraseHash();
 
     if (dataFromFileAsString == null) {
       return "File not picked!";

lib/views/add_edit_note.dart

@@ -6,9 +6,12 @@ import 'package:flutter_keyboard_size/flutter_keyboard_size.dart';
 
 // Project imports:
 import 'package:safenotes/data/database_handler.dart';
+import 'package:safenotes/data/preference_and_config.dart';
 import 'package:safenotes/models/safenote.dart';
 import 'package:safenotes/widgets/note_widget.dart';
 
+import 'package:flutter_nord_theme/flutter_nord_theme.dart';
+
 class AddEditNotePage extends StatefulWidget {
   final SafeNote? note;
 
@@ -63,16 +66,25 @@ class _AddEditNotePageState extends State<AddEditNotePage> {
 
   Widget buildButton() {
     final isFormValid = title.isNotEmpty && description.isNotEmpty;
+    final double buttonFontSize = 17.0;
+    final String buttonText = 'Save';
 
     return Padding(
       padding: EdgeInsets.symmetric(vertical: 8, horizontal: 12),
       child: ElevatedButton(
         style: ElevatedButton.styleFrom(
-          //onPrimary: Colors.white,
-          backgroundColor: isFormValid ? null : Colors.grey.shade700,
+          backgroundColor: isFormValid
+              ? (PreferencesStorage.getIsThemeDark()
+                  ? null
+                  : NordColors.polarNight.darkest)
+              : Colors.grey.shade700,
         ),
         onPressed: addOrUpdateNote,
-        child: Text('Save'),
+        child: Text(
+          buttonText,
+          style:
+              TextStyle(fontSize: buttonFontSize, fontWeight: FontWeight.bold),
+        ),
       ),
     );
   }

lib/views/home.dart

@@ -309,7 +309,7 @@ class _NotesPageState extends State<NotesPage> {
   }
 
   Widget _divide({required double topPadding}) {
-    final bool isDarkTheme = AppSecurePreferencesStorage.getIsThemeDark();
+    final bool isDarkTheme = PreferencesStorage.getIsThemeDark();
 
     return Padding(
       padding: EdgeInsets.only(top: topPadding),

lib/views/login_views/login.dart

@@ -110,7 +110,7 @@ class _EncryptionPhraseLoginPageState extends State<EncryptionPhraseLoginPage> {
   String? _passphraseValidator(String? passphrase) {
     final wrongPhraseMsg = 'Wrong encryption Phrase!';
     return sha256.convert(utf8.encode(passphrase!)).toString() !=
-            AppSecurePreferencesStorage.getPassPhraseHash()
+            PreferencesStorage.getPassPhraseHash()
         ? wrongPhraseMsg
         : null;
   }
@@ -147,7 +147,7 @@ class _EncryptionPhraseLoginPageState extends State<EncryptionPhraseLoginPage> {
     if (form.validate()) {
       final phrase = passPhraseController.text;
       if (sha256.convert(utf8.encode(phrase)).toString() ==
-          AppSecurePreferencesStorage.getPassPhraseHash()) {
+          PreferencesStorage.getPassPhraseHash()) {
         _snackBarMessage(context, 'Decrypting your notes!');
 
         PhraseHandler.initPass(phrase);

lib/views/login_views/set_passphrase.dart

@@ -201,7 +201,7 @@ class _SetEncryptionPhrasePageState extends State<SetEncryptionPhrasePage> {
         _snackBarMessage(context, 'Encryption Phrase Set!');
 
         // Setting hash for PassPhrase in share prefrences
-        AppSecurePreferencesStorage.setPassPhraseHash(
+        PreferencesStorage.setPassPhraseHash(
             sha256.convert(utf8.encode(enteredPassphrase)).toString());
         PhraseHandler.initPass(enteredPassphrase);
         UnDecryptedLoginControl.setNoDecryptionFlag(false);

lib/widgets/note_widget.dart

@@ -1,6 +1,9 @@
 // Flutter imports:
 import 'package:flutter/material.dart';
 
+// Project imports:
+import 'package:safenotes/data/preference_and_config.dart';
+
 class NoteFormWidget extends StatelessWidget {
   final String? title;
   final String? description;
@@ -40,8 +43,11 @@ class NoteFormWidget extends StatelessWidget {
     final double fontSize = 24.0;
     final int maxLinesToShowAtTimeTitle = 2;
     final String titleHint = 'Title';
+    //Disable IMEPL if keyboard incognito mode is true
+    final bool enableIMEPLFlag = !PreferencesStorage.getKeyboardIncognito();
 
     return TextFormField(
+      enableIMEPersonalizedLearning: enableIMEPLFlag,
       maxLines: maxLinesToShowAtTimeTitle,
       initialValue: this.title,
       enableInteractiveSelection: true,
@@ -71,20 +77,15 @@ class NoteFormWidget extends StatelessWidget {
   }
 
   Widget buildDescription(BuildContext context) {
-    final double height = MediaQuery.of(context).size.height;
-    final EdgeInsets padding = MediaQuery.of(context).padding;
-    final double keyboard = MediaQuery.of(context).viewInsets.bottom;
-    final double topFixed = 200.0;
-    final double effectiveHeighOfDevice =
-        height - padding.top - padding.bottom - topFixed - keyboard;
-
-    final double adaptiveScreenFactorForDescription = 25.0;
+    // maxLine is used in resizing description field on keyboard activation or dismissal
     final int maxLinesToShowAtTimeDescription =
-        (effectiveHeighOfDevice / adaptiveScreenFactorForDescription).round();
+        computeMaxLine(context: context, fontHeight: 30.0);
     final double fontSize = 18.0;
     final String hintDescription = 'Type something...';
+    final bool enableIMEPLFlag = !PreferencesStorage.getKeyboardIncognito();
 
     return TextFormField(
+      enableIMEPersonalizedLearning: enableIMEPLFlag,
       maxLines: maxLinesToShowAtTimeDescription,
       initialValue: this.description,
       enableInteractiveSelection: true,
@@ -111,4 +112,33 @@ class NoteFormWidget extends StatelessWidget {
         ? descriptionCantBeEmptyMsg
         : null;
   }
+
+  int computeMaxLine(
+      {required BuildContext context, required double fontHeight}) {
+    final double totalHeight = MediaQuery.of(context).size.height;
+    final EdgeInsets paddingInsets = MediaQuery.of(context).padding;
+    final double keyboard = MediaQuery.of(context).viewInsets.bottom;
+    final double padding = paddingInsets.top + paddingInsets.bottom;
+
+    double totalHeightRatio = (totalHeight - padding) / 100;
+    double fontHeightRatio = fontHeight / 100;
+    double theXfactor = totalHeightRatio / 3.2;
+    /*
+    When Keyboard is on screen:-
+    Theoretical Ratios for top:description:keyboard 
+    theoreticalTitleNTopHeightRatio = x; 
+    theoreticalDescriptinHeightRatio = x*1.2; 
+    theoreticalKeyboardHeightRatio = x;
+    x + x*1.2 + x = totalHeightRatio (i.e total height of screen)
+    
+    From above:
+    if keyboard is on-screen:
+      theoreticalDescriptinHeightRatio = x*1.2
+    if keyboard not on screen:
+      theoreticalDescriptinHeightRatio = x*2.2 (keyboard space is taken by description)
+    */
+    double descriptionRatio = theXfactor * 2.2;
+    if (keyboard > 1) descriptionRatio = theXfactor * 1.2;
+    return (descriptionRatio / fontHeightRatio).round();
+  }
 }

lib/widgets/search_widget.dart

@@ -1,6 +1,9 @@
 // Flutter imports:
 import 'package:flutter/material.dart';
 
+// Project imports:
+import 'package:safenotes/data/preference_and_config.dart';
+
 class SearchWidget extends StatefulWidget {
   final String text;
   final ValueChanged<String> onChanged;
@@ -26,6 +29,7 @@ class _SearchWidgetState extends State<SearchWidget> {
     final styleHint = TextStyle(color: Colors.black54);
     final style = widget.text.isEmpty ? styleHint : styleActive;
     final searchBoxRadius = 7.0;
+    final bool enableIMEPLFlag = !PreferencesStorage.getKeyboardIncognito();
 
     return Container(
       height: 42,
@@ -37,6 +41,7 @@ class _SearchWidgetState extends State<SearchWidget> {
       ),
       padding: const EdgeInsets.symmetric(horizontal: 8),
       child: TextField(
+        enableIMEPersonalizedLearning: enableIMEPLFlag,
         controller: controller,
         enableInteractiveSelection: true,
         //autofocus: true,