From 4c3a0f407566cd5b48435c0d2c1662415c961db3 Mon Sep 17 00:00:00 2001
From: Alyssa <alyssa.burlton@gmail.com>
Date: Wed, 18 Sep 2024 22:54:48 +0100
Subject: [PATCH] fix formatting, more intelligible file size stuff

---
 core/src/main/kotlin/utils/MathsUtil.kt     | 21 +++++++++++++--------
 core/src/test/kotlin/utils/MathsUtilTest.kt |  2 ++
 2 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/core/src/main/kotlin/utils/MathsUtil.kt b/core/src/main/kotlin/utils/MathsUtil.kt
index a440200..a5ed961 100644
--- a/core/src/main/kotlin/utils/MathsUtil.kt
+++ b/core/src/main/kotlin/utils/MathsUtil.kt
@@ -1,4 +1,4 @@
-import kotlin.math.log2
+import kotlin.math.log
 import kotlin.math.pow
 
 fun getPercentage(count: Number, total: Number, digits: Int = 1) =
@@ -20,10 +20,15 @@ private fun round(number: Double, decimalPlaces: Int): Double {
     return rounded / powerOfTen
 }
 
-fun Long.formatAsFileSize(): String = log2(coerceAtLeast(1).toDouble()).toInt().div(10).let {
-    val precision = when (it) {
-        0 -> 0; else -> 1;
-    }
-    val prefix = arrayOf("", "K", "M", "G", "T", "P", "E", "Z", "Y")
-    String.format("%.${precision}f ${prefix[it]}B", toDouble() / 2.0.pow(it * 10.0))
-}
\ No newline at end of file
+fun Long.formatAsFileSize(): String {
+    if (this == 0L) return "0 B"
+
+    val magnitudeIndex = log(toDouble(), 1024.0).toInt()
+    val precision = if (magnitudeIndex == 0) 0 else 1
+    val units = listOf("B", "KB", "MB", "GB", "TB")
+
+    return String.format(
+        "%.${precision}f ${units[magnitudeIndex]}",
+        toDouble() / 1024.0.pow(magnitudeIndex)
+    )
+}
diff --git a/core/src/test/kotlin/utils/MathsUtilTest.kt b/core/src/test/kotlin/utils/MathsUtilTest.kt
index 83d8714..01443d6 100644
--- a/core/src/test/kotlin/utils/MathsUtilTest.kt
+++ b/core/src/test/kotlin/utils/MathsUtilTest.kt
@@ -40,9 +40,11 @@ class MathsUtilTest : AbstractTest() {
 
     @Test
     fun `Format as file size`() {
+        0L.formatAsFileSize() shouldBe "0 B"
         568L.formatAsFileSize() shouldBe "568 B"
         1024L.formatAsFileSize() shouldBe "1.0 KB"
         34304L.formatAsFileSize() shouldBe "33.5 KB"
         5242880L.formatAsFileSize() shouldBe "5.0 MB"
+        107374182400L.formatAsFileSize() shouldBe "100.0 GB"
     }
 }