Merged QuickLook.Common from submodule

https://github.com/QL-Win/QuickLook.Common/commit/529d07b56577b88329481cdac8f2a6a175b6c21a

QuickLook.Common/ExtensionMethods/FileExtensions.cs

@@ -0,0 +1,47 @@
+// Copyright © 2017-2026 QL-Win Contributors
+//
+// This file is part of QuickLook program.
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+using System;
+
+namespace QuickLook.Common.ExtensionMethods;
+
+public static class FileExtensions
+{
+    public static string ToPrettySize(this long value, int decimalPlaces = 0)
+    {
+        const long OneKb = 1024L;
+        const long OneMb = OneKb * 1024L;
+        const long OneGb = OneMb * 1024L;
+        const long OneTb = OneGb * 1024L;
+
+        var asTb = Math.Round((double)value / OneTb, decimalPlaces);
+        var asGb = Math.Round((double)value / OneGb, decimalPlaces);
+        var asMb = Math.Round((double)value / OneMb, decimalPlaces);
+        var asKb = Math.Round((double)value / OneKb, decimalPlaces);
+        var chosenValue = asTb > 1
+            ? $"{asTb} TB"
+            : asGb > 1
+                ? $"{asGb} GB"
+                : asMb > 1
+                    ? $"{asMb} MB"
+                    : asKb > 1
+                        ? $"{asKb} KB"
+                        : $"{Math.Round((double)value, decimalPlaces)} bytes";
+
+        return chosenValue;
+    }
+}