From f0e5648ad9cbc686956f2b9be60d0f6bdfad0b04 Mon Sep 17 00:00:00 2001
From: Piotr Stachyra <piotr.stachyra@gmail.com>
Date: Fri, 14 Nov 2025 11:13:00 +0100
Subject: [PATCH 1/2] show 0 balance with decimals in classic denomination

---
 app/src/main/java/to/bitkit/models/Currency.kt | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/app/src/main/java/to/bitkit/models/Currency.kt b/app/src/main/java/to/bitkit/models/Currency.kt
index 937d8491bf..ebef4fd36a 100644
--- a/app/src/main/java/to/bitkit/models/Currency.kt
+++ b/app/src/main/java/to/bitkit/models/Currency.kt
@@ -106,12 +106,16 @@ fun Long.formatToModernDisplay(locale: Locale = Locale.getDefault()): String {
 fun ULong.formatToModernDisplay(locale: Locale = Locale.getDefault()): String = toLong().formatToModernDisplay(locale)
 
 fun Long.formatToClassicDisplay(locale: Locale = Locale.getDefault()): String {
-    val sats = this
     val symbols = DecimalFormatSymbols(locale).apply {
         decimalSeparator = DECIMAL_SEPARATOR
     }
-    val formatter = DecimalFormat("###.########", symbols)
-    return formatter.format(sats.asBtc())
+    val pattern = "0.${"0".repeat(CLASSIC_DECIMALS)}"
+    val formatter = DecimalFormat(pattern, symbols).apply {
+        minimumFractionDigits = CLASSIC_DECIMALS
+        maximumFractionDigits = CLASSIC_DECIMALS
+        isGroupingUsed = false
+    }
+    return formatter.format(asBtc())
 }
 
 fun BigDecimal.formatCurrency(decimalPlaces: Int = FIAT_DECIMALS, locale: Locale = Locale.getDefault()): String? {

From 3e7b5f63ef11c9d329f7378f43c2ba1b90afc128 Mon Sep 17 00:00:00 2001
From: Piotr Stachyra <piotr.stachyra@gmail.com>
Date: Fri, 14 Nov 2025 12:01:53 +0100
Subject: [PATCH 2/2] basic unit tests for formatToModernDisplay and
 formatToClassicDisplay

---
 .../java/to/bitkit/models/CurrencyTest.kt     | 40 +++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 app/src/test/java/to/bitkit/models/CurrencyTest.kt

diff --git a/app/src/test/java/to/bitkit/models/CurrencyTest.kt b/app/src/test/java/to/bitkit/models/CurrencyTest.kt
new file mode 100644
index 0000000000..7b9ad33240
--- /dev/null
+++ b/app/src/test/java/to/bitkit/models/CurrencyTest.kt
@@ -0,0 +1,40 @@
+package to.bitkit.models
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+import java.util.Locale
+
+class CurrencyTest {
+
+    @Test
+    fun `formatToModernDisplay uses space grouping`() {
+        val sats = 123_456_789L
+
+        val formatted = sats.formatToModernDisplay(Locale.US)
+
+        assertEquals("123 456 789", formatted)
+    }
+
+    @Test
+    fun `formatToModernDisplay handles zero`() {
+        val formatted = 0L.formatToModernDisplay(Locale.US)
+
+        assertEquals("0", formatted)
+    }
+
+    @Test
+    fun `formatToClassicDisplay always shows eight decimals`() {
+        val formatted = 0L.formatToClassicDisplay(Locale.US)
+
+        assertEquals("0.00000000", formatted)
+    }
+
+    @Test
+    fun `formatToClassicDisplay converts sats to btc`() {
+        val sats = 12_345L // 0.00012345 BTC
+
+        val formatted = sats.formatToClassicDisplay(Locale.US)
+
+        assertEquals("0.00012345", formatted)
+    }
+}