[Android] Fix the filename "natural" sort when file names have prepending 0

[Nicolas Pomepuy]

vlc-android | branch: master | Nicolas Pomepuy <nicolas at videolabs.io> | Wed Sep 21 07:38:18 2022 +0200| [8ece1989eed9fafde6465382895c6d3cac361a31] | committer: Duncan McNamara

Fix the filename "natural" sort when file names have prepending 0

> https://code.videolan.org/videolan/vlc-android/commit/8ece1989eed9fafde6465382895c6d3cac361a31
---

 .../vlc-android/src/org/videolan/vlc/util/Kextensions.kt    | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/application/vlc-android/src/org/videolan/vlc/util/Kextensions.kt b/application/vlc-android/src/org/videolan/vlc/util/Kextensions.kt
index 6f08794aa..605150f8d 100644
--- a/application/vlc-android/src/org/videolan/vlc/util/Kextensions.kt
+++ b/application/vlc-android/src/org/videolan/vlc/util/Kextensions.kt
@@ -392,7 +392,11 @@ fun <T> Flow<T>.launchWhenStarted(scope: LifecycleCoroutineScope): Job = scope.l
 fun String?.sanitizeStringForAlphaCompare(nbOfDigits: Int): String? {
     if (this == null) return null
     if (first().isDigit()) return buildString {
-        for (i in 0 until (nbOfDigits - (getStartingNumber()?.numberOfDigits() ?: 0))) {
+        var numberOfPrependingZeros =0
+        for (c in this at sanitizeStringForAlphaCompare) {
+            if (c.isDigit() && c.digitToInt() == 0) numberOfPrependingZeros++ else break
+        }
+        for (i in 0 until (nbOfDigits - numberOfPrependingZeros - (getStartingNumber()?.numberOfDigits() ?: 0))) {
             append("0")
         }
         append(this at sanitizeStringForAlphaCompare)
@@ -419,9 +423,10 @@ fun String.getStartingNumber(): Int? {
     return try {
         buildString {
             for (c in this at getStartingNumber)
-                if (c.isDigit())
-                    append(c)
-                else break
+                //we exclude starting "0" to prevent bad sorts
+                if (c.isDigit()) {
+                    if (!(this.isEmpty() && c.digitToInt() == 0)) append(c)
+                } else break
         }.toInt()
     } catch (e: NumberFormatException) {
         null