From 0a26e42b6f271bad2a95330d4de24334b5ce69c6 Mon Sep 17 00:00:00 2001
From: Jaidyn Ann <10477760+JadedCtrl@users.noreply.github.com>
Date: Tue, 28 May 2024 23:12:36 -0500
Subject: [PATCH] Fix URL-encoding issue with port-numbers

:80 and :443 would be redundantly added to HTTP
and HTTPS URLs, respectively.
---
 src/mirror-img.lisp | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/src/mirror-img.lisp b/src/mirror-img.lisp
index 587453c..52b7544 100644
--- a/src/mirror-img.lisp
+++ b/src/mirror-img.lisp
@@ -151,10 +151,10 @@ already set)."
 “https://invalid.tld/dad alive.jpg” → “https://invalid.tld/dad%20alive.jpg”"
  (let ((uri (quri:uri uri)))
    (format nil "~@[~A://~]~A~@[:~A~]~A"
-            (quri:uri-scheme uri)
-            (quri:uri-host uri)
-            (quri:uri-port uri)
-            (url-encode-path (quri:uri-path uri)))))
+           (quri:uri-scheme uri)
+           (quri:uri-host uri)
+           (uri-explicit-port uri)
+           (url-encode-path (quri:uri-path uri)))))
 
 ;; string → string
 (defun url-encode-path (path)
@@ -166,3 +166,15 @@ already set)."
       (lambda (a b)
         (format nil "~A/~A" a b))
       (mapcar #'quri:url-encode path-parts))))
+
+;; quri-uri → number
+(defun uri-explicit-port (uri)
+  "Given a HTTP/HTTPS URI, return a port-number if it isn’t implied by the protocol.
+That is, 443 is implied by HTTPS, so nil is returned; but 998 wouldn’t be implied."
+  (let ((scheme (quri:uri-scheme uri))
+        (port (quri:uri-port uri)))
+    (unless (or (and (equal scheme "https")
+                     (eq port 443))
+                (and (equal scheme "http")
+                     (eq port 80)))
+      port)))