Unicode to English literals

README.md

@@ -224,6 +224,24 @@ print(NepaliMoment.fromAD(DateTime.parse('2019-06-02T18:22:14'),
 // १३ दिन पहिले
 ```
 
+### English literals to Unicode
+Converts English literal (Roman Literals) into Nepali Unicode.
+```dart 
+      print(
+        NepaliUnicode.convert(
+          "sayau' thu''gaa fUlakaa haamii, euTai maalaa nepaalii",
+        ),
+      );
+// सयौं थुँगा फूलका हामी, एउटै माला नेपाली
+```
+
+### Unicode to English iterals
+Converts Nepali Unicode into English literals.
+```dart
+print(NepaliUnicode.convert("सयौं थुँगा फूलका हामी, एउटै माला नेपाली"));
+// sayau' thu''gaa fUlakaa haamii, euTai maalaa nepaalii 
+```
+
 
 ## Example
 Find more detailed example [here](https://github.com/sarbagyastha/nepali_utils/tree/master/example/main.dart).

example/main.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:nepali_utils/nepali_utils.dart';
+import 'package:nepali_utils/src/unicode_to_english.dart';
 
 void main(List<String> arguments) {
   heading('Nepali Date Time');
@@ -74,6 +75,9 @@ void main(List<String> arguments) {
       "sayau' thu''gaa fUlakaa haamii, euTai maalaa nepaalii"));
   print(NepaliUnicode.convert(
       'saarwabhauma bhai failiekaa, mecii-mahaakaalii\n'));
+  heading('Unicode to English');
+  print(UnicodeToEnglish.convert('सयौं थुँगा फूलका हामी, एउटै माला नेपाली'));
+  print(UnicodeToEnglish.convert('सार्वभौम भै फैलिएका, मेची-महाकाली\n'));
 }
 
 void heading(String text) {

lib/src/unicode_to_english.dart

@@ -0,0 +1,124 @@
+// Copyright 2020 Sarbagya Dhaubanjar. All rights reserved.
+// Use of this source code is governed by a MIT license that can be
+// found in the LICENSE file.
+
+/// Converts Nepali Unicode (Devnagari Literals) into English(Roman) literals.
+class UnicodeToEnglish {
+  /// Converts specifies [text] into english literals.
+  ///
+  /// if live is true, texts will convert in live manner.
+  /// i.e. as you go on typing
+  /// Default for live is false.
+  static String convert(String text, {bool live = false}) {
+    final characters = text.split('');
+    final convertedString = <String>[];
+    for (var i = 0; i < characters.length; i++) {
+      if (i < characters.length - 1 && characters[i + 1] == '\u094D') {
+        var character = _unicodeMap[characters[i]].toString();
+        character = character.substring(0, character.length - 1);
+        convertedString.add(character);
+      } else if (characters[i] != '\u094D') {
+        convertedString.add(
+          _unicodeMap[characters[i]] ?? characters[i],
+        );
+      }
+    }
+    for (var i = 0; i < convertedString.length; i++) {
+      // if the converted string contains symbols
+      if (_symbolMap[convertedString[i]] != null) {
+        var preecedingCharacter = convertedString[i - 1].toString();
+        print('$preecedingCharacter ${preecedingCharacter.endsWith('a')}');
+        //  eg. tha + ु (u) = thu
+        if (preecedingCharacter.endsWith('a')) {
+          preecedingCharacter =
+              preecedingCharacter.substring(0, preecedingCharacter.length - 1);
+          convertedString[i - 1] = preecedingCharacter;
+        }
+
+        convertedString[i] = _symbolMap[convertedString[i]] ?? '';
+      }
+    }
+    return convertedString.join('');
+  }
+}
+
+const Map<String, String> _unicodeMap = {
+  //ka - gya
+  '\u0915': 'ka',
+  '\u0916': 'kha',
+  '\u0917': 'ga',
+  '\u0918': 'gha',
+  '\u0919': 'ng',
+  '\u091A': 'ca',
+  '\u091B': 'cha',
+  '\u091C': 'ja',
+  '\u091D': 'jha',
+  '\u091E': 'ya',
+  '\u091F': 'Ta',
+  '\u0920': 'Tha',
+  '\u0921': 'Da',
+  '\u0922': 'Dha',
+  '\u0923': 'na',
+  '\u0924': 'ta',
+  '\u0925': 'tha',
+  '\u0926': 'da',
+  '\u0927': 'dha',
+  '\u0928': 'na',
+  '\u092A': 'pa',
+  '\u092B': 'fa',
+  '\u092C': 'ba',
+  '\u092D': 'bha',
+  '\u092E': 'ma',
+  '\u092F': 'ya',
+  '\u0930': 'ra',
+  '\u0932': 'la',
+  '\u0935': 'wa',
+  '\u0936': 'sha',
+  '\u0937': 'sha',
+  '\u0938': 'sa',
+  '\u0939': 'ha',
+  '\u0915\u094D\u0937': 'xa',
+  '\u0924\u094D\u0930': 'tra',
+  '\u091C\u094D\u091E': 'gya',
+  // a - ahm
+  '\u0905': 'a',
+  '\u0906': 'aa',
+  '\u0907': 'i',
+  '\u0908': 'ii',
+  '\u0909': 'u',
+  '\u090A': 'oo',
+  '\u090F': 'e',
+  '\u0910': 'ai',
+  '\u0913': 'o',
+  '\u0914': 'au',
+  '\u0935\u0902': 'am',
+  '\u0935\u0903': 'ah',
+
+  //numbers
+  '\u0966': '0',
+  '\u0967': '1',
+  '\u0968': '2',
+  '\u0969': '3',
+  '\u096a': '4',
+  '\u096b': '5',
+  '\u096c': '6',
+  '\u096d': '7',
+  '\u096e': '8',
+  '\u096f': '9',
+  //symbols
+  '%2c': ',',
+};
+const Map<String, String> _symbolMap = {
+  '\u093E': 'aa',
+  '\u093F': 'i',
+  '\u0940': 'ii',
+  '\u0941': 'u',
+  '\u0942': 'U',
+  '\u0947': 'e',
+  '\u0948': 'ai',
+  '\u094B': 'o',
+  '\u094C': 'au',
+
+  '\u0901': "''", //chandrabindu
+  '\u0902': "'", //shreebindu
+};

test/nepali_number_format_test.dart

@@ -1,4 +1,5 @@
 import 'package:nepali_utils/nepali_utils.dart';
+import 'package:nepali_utils/src/unicode_to_english.dart';
 import 'package:test/test.dart';
 
 void main() {
@@ -164,6 +165,25 @@ void main() {
       ),
     );
   });
+  group('text converter ', () {
+    final englishText =
+        "ka baaTa kachuwaa kha kharaayo\nkharaayoko sing' chaina kataa haraayo";
+    final nepaliText = 'क बाट कछुवा ख खरायो\nखरायोको सिङं छैन कता हरायो';
+    test(
+      'conversion of english to nepali unicode',
+      () => expect(
+        NepaliUnicode.convert('$englishText'),
+        '$nepaliText',
+      ),
+    );
+    test(
+      'conversion of nepali to english unicode',
+      () => expect(
+        UnicodeToEnglish.convert('$nepaliText'),
+        '$englishText',
+      ),
+    );
+  });
 }
 
 String _format(number) => NepaliNumberFormat().format(number);