From e08e3e995b6dd65163534128f0815413159189e5 Mon Sep 17 00:00:00 2001
From: Konstantin Serov <konstantin.p.serov@gmail.com>
Date: Sat, 20 Aug 2022 19:24:19 +0700
Subject: [PATCH] Fixed
 https://github.com/caseyryan/flutter_multi_formatter/issues/87

---
 CHANGELOG.md                                 |  2 ++
 example/lib/pages/money_format_page.dart     |  1 +
 lib/flutter_multi_formatter.dart             |  2 +-
 lib/formatters/currency_input_formatter.dart |  9 +++++---
 lib/formatters/formatter_utils.dart          | 22 +++++++++++---------
 pubspec.yaml                                 |  2 +-
 6 files changed, 23 insertions(+), 15 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 46d591c..01b2d60 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,5 @@
+## [2.6.1]
+- Fixed currency input formatter empty value error https://github.com/caseyryan/flutter_multi_formatter/issues/87
 ## [2.6.0]
 - Made it possible to enter a leading plus https://github.com/caseyryan/flutter_multi_formatter/issues/85
 - Fixed https://github.com/caseyryan/flutter_multi_formatter/issues/80
diff --git a/example/lib/pages/money_format_page.dart b/example/lib/pages/money_format_page.dart
index a268089..8e8bf09 100644
--- a/example/lib/pages/money_format_page.dart
+++ b/example/lib/pages/money_format_page.dart
@@ -106,6 +106,7 @@ class _MoneyFormatPageState extends State<MoneyFormatPage> {
                   inputFormatters: [
                     CurrencyInputFormatter(
                       trailingSymbol: CurrencySymbols.EURO_SIGN,
+                      mantissaLength: 0,
                     )
                   ],
                 ),
diff --git a/lib/flutter_multi_formatter.dart b/lib/flutter_multi_formatter.dart
index a524d45..83b710e 100644
--- a/lib/flutter_multi_formatter.dart
+++ b/lib/flutter_multi_formatter.dart
@@ -41,4 +41,4 @@ export 'formatters/pos_input_formatter.dart';
 export 'utils/bitcoin_validator/bitcoin_validator.dart';
 export 'utils/bitcoin_validator/bitcoin_wallet_details.dart';
 export 'utils/enum_utils.dart';
-export 'utils/unfocuser.dart';
+export 'utils/unfocuser.dart';
\ No newline at end of file
diff --git a/lib/formatters/currency_input_formatter.dart b/lib/formatters/currency_input_formatter.dart
index c24e9ee..8e2f786 100644
--- a/lib/formatters/currency_input_formatter.dart
+++ b/lib/formatters/currency_input_formatter.dart
@@ -103,8 +103,8 @@ class CurrencyInputFormatter extends TextInputFormatter {
   ) {
     final trailingLength = _getTrailingLength();
     final leadingLength = _getLeadingLength();
-    final oldCaretIndex = oldValue.selection.start;
-    final newCaretIndex = newValue.selection.start;
+    final oldCaretIndex = max(oldValue.selection.start, oldValue.selection.end);
+    final newCaretIndex = max(newValue.selection.start, newValue.selection.end);
     var newText = newValue.text;
 
     final newAsNumeric = toNumericString(
@@ -124,7 +124,7 @@ class CurrencyInputFormatter extends TextInputFormatter {
         shorterString: newText,
         longerString: oldText,
       )) {
-        // print('RETURN 2 ${oldValue.text}');
+        // print('RETURN 2 ${oldValue.text},  $oldCaretIndex');
         return oldValue.copyWith(
           selection: TextSelection.collapsed(
             offset: oldCaretIndex - 1,
@@ -335,6 +335,9 @@ class CurrencyInputFormatter extends TextInputFormatter {
     required String oldText,
     required int oldCaretOffset,
   }) {
+    if (mantissaLength < 1) {
+      return 0;
+    }
     final mantissaIndex = oldText.lastIndexOf(
       _mantissaSeparatorRegexp,
     );
diff --git a/lib/formatters/formatter_utils.dart b/lib/formatters/formatter_utils.dart
index 7082af7..0e2b122 100644
--- a/lib/formatters/formatter_utils.dart
+++ b/lib/formatters/formatter_utils.dart
@@ -71,7 +71,6 @@ String toNumericString(
   }
   try {
     if (allowPeriod) {
-      // return double.parse(result).toString();
       return _toDoubleString(
         result,
         allowPeriod: true,
@@ -142,8 +141,15 @@ String _toDoubleString(
     } else if (temp[0] == period) {
       temp.insert(0, zero);
     }
+  } else {
+    while (temp.length > 1) {
+      if (temp.first == zero) {
+        temp.removeAt(0);
+      } else {
+        break;
+      }
+    }
   }
-
   return temp.join();
 }
 
@@ -251,8 +257,7 @@ String toCurrencyString(
     if (isNegative) {
       var containsMinus = parsed.toString().contains('-');
       if (!containsMinus) {
-        value =
-            '-${parsed.toStringAsFixed(mantissaLength).replaceFirst('0.', '.')}';
+        value = '-${parsed.toStringAsFixed(mantissaLength).replaceFirst('0.', '.')}';
       } else {
         value = '${parsed.toStringAsFixed(mantissaLength)}';
       }
@@ -317,9 +322,8 @@ String toCurrencyString(
     }
   }
 
-  mantissa = noShortening
-      ? _postProcessMantissa(mantissaList.join(''), mantissaLength)
-      : '';
+  mantissa =
+      noShortening ? _postProcessMantissa(mantissaList.join(''), mantissaLength) : '';
   var maxIndex = split.length - 1;
   if (mantissaSeparatorIndex > 0 && noShortening) {
     maxIndex = mantissaSeparatorIndex - 1;
@@ -337,9 +341,7 @@ String toCurrencyString(
       } else {
         if (value.length >= minShorteningLength) {
           if (!isDigit(split[i])) digitCounter = 1;
-          if (digitCounter % 3 == 1 &&
-              digitCounter > 1 &&
-              i > (isNegative ? 1 : 0)) {
+          if (digitCounter % 3 == 1 && digitCounter > 1 && i > (isNegative ? 1 : 0)) {
             list.add(tSeparator);
           }
         }
diff --git a/pubspec.yaml b/pubspec.yaml
index 5a5083a..12f2c1d 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,6 @@
 name: flutter_multi_formatter
 description: A package of formatters for international phone numbers, credit / debit cards and a masked formatter
-version: 2.6.0
+version: 2.6.1
 homepage: https://github.com/caseyryan/flutter_multi_formatter
 
 environment: