From 5276f2ba6fa72e0fb8fb2f4be9fc578416488836 Mon Sep 17 00:00:00 2001
From: celogeek <65178+celogeek@users.noreply.github.com>
Date: Tue, 11 Apr 2023 17:35:14 +0200
Subject: [PATCH] improve fmt part, using consistant size

---
 internal/epub/core.go | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/internal/epub/core.go b/internal/epub/core.go
index b6d7b1c..da0ff2c 100644
--- a/internal/epub/core.go
+++ b/internal/epub/core.go
@@ -247,7 +247,9 @@ func (e *ePub) Write() error {
 		ext := filepath.Ext(e.Output)
 		suffix := ""
 		if totalParts > 1 {
-			suffix = fmt.Sprintf(" Part %02d of %02d", i+1, totalParts)
+			fmtLen := len(fmt.Sprint(totalParts))
+			fmtPart := fmt.Sprintf(" Part %%0%dd of %%0%dd", fmtLen, fmtLen)
+			suffix = fmt.Sprintf(fmtPart, i+1, totalParts)
 		}
 
 		path := fmt.Sprintf("%s%s%s", e.Output[0:len(e.Output)-len(ext)], suffix, ext)