From 493124b485bfa44bacbcadfd6469bb2683465a2c Mon Sep 17 00:00:00 2001
From: Konstantin Ullrich <konstantinullrich12@gmail.com>
Date: Tue, 25 Feb 2025 13:22:02 +0100
Subject: [PATCH] feat: Improve compatibility for japanese strings

---
 CHANGELOG.md                         |  6 +++++-
 lib/src/mnemonics/polyseed_lang.dart | 12 +++++++++---
 lib/src/polyseed.dart                | 17 +++++++++++------
 pubspec.yaml                         |  2 +-
 test/polyseed_test.dart              | 19 +++++++++++++++++++
 5 files changed, 45 insertions(+), 11 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 925c12a..bb4bdce 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,8 @@
-## 0.0.5
+## 0.0.7
+
+- Improve compatibility with japanese strings using U+0020 separators
+
+## 0.0.6
 
 - Make getters less strict
 - Support up-to-date dependencies
diff --git a/lib/src/mnemonics/polyseed_lang.dart b/lib/src/mnemonics/polyseed_lang.dart
index 92491d7..a9751c1 100644
--- a/lib/src/mnemonics/polyseed_lang.dart
+++ b/lib/src/mnemonics/polyseed_lang.dart
@@ -60,13 +60,15 @@ class PolyseedLang {
 
   /// Get the [PolyseedLang] by it's english name eg. "Chinese (Simplified)"
   static PolyseedLang getByEnglishName(String englishName) =>
-      languages.firstWhere((e) => e.nameEnglish.toLowerCase() == englishName.toLowerCase());
+      languages.firstWhere(
+          (e) => e.nameEnglish.toLowerCase() == englishName.toLowerCase());
 
   /// Get the [PolyseedLang] using the words of [phrase]
   static PolyseedLang getByPhrase(String phrase) {
     for (var language in languages) {
       phrase = language.hasAccents ? unorm.nfkd(phrase) : phrase;
-      final phraseWords = phrase.split(language.separator);
+      final phraseWords =
+          language.normalizeSeparator(phrase).split(language.separator);
       if (language.words.containsAll(phraseWords)) {
         return language;
       }
@@ -85,7 +87,7 @@ class PolyseedLang {
   }
 
   /// Decode a valid seed [phrase] into it's coefficients
-  List<int> decodePhrase(String phrase) => phrase
+  List<int> decodePhrase(String phrase) => normalizeSeparator(phrase)
       .split(separator)
       .map((e) => words.indexOf(hasAccents ? unorm.nfkd(e) : e))
       .toList();
@@ -93,4 +95,8 @@ class PolyseedLang {
   /// Encode a seed [coefficients] into a valid seed phrase
   String encodePhrase(List<int> coefficients) =>
       coefficients.map((e) => words[e]).join(separator);
+
+  /// Replace space with the expected [separator] to improve compatibility
+  String normalizeSeparator(String phrase) =>
+      separator != '\u0020' ? phrase.replaceAll("\u0020", separator) : phrase;
 }
diff --git a/lib/src/polyseed.dart b/lib/src/polyseed.dart
index 9a09690..bb6c5f3 100644
--- a/lib/src/polyseed.dart
+++ b/lib/src/polyseed.dart
@@ -21,11 +21,15 @@ class Polyseed {
   late PolyseedData _data;
 
   /// Check if a seed is a valid Polyseed
-  static bool isValidSeed(String phrase) {
-    if (!PolyseedLang.isValidPhrase(phrase)) return false;
-    final lang = PolyseedLang.getByPhrase(phrase);
-
-    return phrase.split(lang.separator).length == numberOfWords;
+  static bool isValidSeed(String phrase, [PolyseedLang? lang]) {
+    if (lang != null && !PolyseedLang.isValidPhrase(phrase)) return false;
+    final polyseedLang = lang ?? PolyseedLang.getByPhrase(phrase);
+
+    return polyseedLang
+        .normalizeSeparator(phrase)
+        .split(polyseedLang.separator)
+        .length ==
+        numberOfWords;
   }
 
   /// Create a random [Polyseed]
@@ -66,9 +70,10 @@ class Polyseed {
   Polyseed.decode(String str, PolyseedLang lang, PolyseedCoin coin) {
     assert(coin.index < GFPoly.size);
 
-    final words = str.split(lang.separator);
+    final words = lang.normalizeSeparator(str).split(lang.separator);
     final poly = GFPoly();
 
+    
     // split into words
     if (words.length != numberOfWords) {
       throw WordNumberException();
diff --git a/pubspec.yaml b/pubspec.yaml
index 03d6f07..2fa0a44 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,6 @@
 name: polyseed
 description: A pure dart implementation of the 16-word seed scheme for monero
-version: 0.0.6
+version: 0.0.7
 homepage: https://cakelabs.com
 repository: https://github.com/cake-tech/polyseed_dart
 issue_tracker: https://github.com/cake-tech/polyseed_dart/issues
diff --git a/test/polyseed_test.dart b/test/polyseed_test.dart
index a9e4142..d1abcf0 100644
--- a/test/polyseed_test.dart
+++ b/test/polyseed_test.dart
@@ -2,6 +2,7 @@ import 'dart:convert';
 
 import 'package:polyseed/polyseed.dart';
 import 'package:polyseed/src/mnemonics/es_lang.dart';
+import 'package:polyseed/src/mnemonics/jp_lang.dart';
 import 'package:test/test.dart';
 
 void main() {
@@ -118,6 +119,24 @@ void main() {
         expect(legacySeed,
             "remedio haz ébano lobo orden celda pezuña regreso ardilla estar acelga fallo punto nación hada quitar ancla obeso piedra pausa helio fuente joroba pista quitar");
       });
+
+      test('Edge Case: Japanese seed with normal space separator', () {
+        final seed =
+            "せつぶん いせい てはい けんか たてる ねんきん くたびれる いよく やたい あいこくしん ちきゅう きたえる せたけ あひる かのう げつれい";
+
+        final detectedLang = PolyseedLang.getByPhrase(seed);
+        expect(detectedLang, jpLang);
+
+        final isValidSeed = Polyseed.isValidSeed(seed);
+        expect(isValidSeed, true);
+
+        final key = Polyseed.decode(seed, jpLang, coin)
+            .generateKey(coin, 32)
+            .toHexString();
+
+        expect(key,
+            "340593b3fd0b2670b4727b6a9b64f3f817e2b97fcb26ea3ae8467234eb857f95");
+      });
     });
   });
 }