From d58c83fbd8947323a4c2d5df579a41b82497686e Mon Sep 17 00:00:00 2001
From: Alex Ling <hkalexling@gmail.com>
Date: Fri, 27 Mar 2020 04:45:03 +0000
Subject: [PATCH] Use BigInt when sorting filenames (#22)

---
 spec/util_spec.cr | 8 ++++++++
 src/util.cr       | 4 +++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/spec/util_spec.cr b/spec/util_spec.cr
index b2f2c2c..47e26d6 100644
--- a/spec/util_spec.cr
+++ b/spec/util_spec.cr
@@ -25,4 +25,12 @@ describe "compare_alphanumerically" do
 			compare_alphanumerically a, b
 		}.should eq ary
 	end
+
+	# https://github.com/hkalexling/Mango/issues/22
+	it "handles numbers larger than Int32" do
+		ary = ["14410155591588.jpg", "21410155591588.png", "104410155591588.jpg"]
+		ary.reverse.sort {|a, b|
+			compare_alphanumerically a, b
+		}.should eq ary
+	end
 end
diff --git a/src/util.cr b/src/util.cr
index 2370c40..ca7b08d 100644
--- a/src/util.cr
+++ b/src/util.cr
@@ -1,3 +1,5 @@
+require "big"
+
 IMGS_PER_PAGE = 5
 
 macro layout(name)
@@ -56,7 +58,7 @@ def compare_alphanumerically(c, d)
 		return -1 if a.nil?
 		return 1 if b.nil?
 		if is_numeric(a) && is_numeric(b)
-			compare = a.to_i <=> b.to_i
+			compare = a.to_big_i <=> b.to_big_i
 			return compare if compare != 0
 		else
 			compare = a <=> b