From dbd9221931ddffa0f205398cb54af046d9759d5a Mon Sep 17 00:00:00 2001
From: Alexander Borsuk <me@alex.bio>
Date: Fri, 5 May 2023 00:49:32 +0200
Subject: [PATCH] Fixed improperly encoded windows-1251 names when sharing
 bookmarks in vk

Signed-off-by: Alexander Borsuk <me@alex.bio>
---
 src/ge0.ts | 26 +++++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/src/ge0.ts b/src/ge0.ts
index 2bc313b..c227494 100644
--- a/src/ge0.ts
+++ b/src/ge0.ts
@@ -9,10 +9,34 @@ function replaceInTemplate(template: string, data: Record<string, any>) {
   return template.replace(pattern, (_, token) => data[token] || '');
 }
 
+function fromWindows1251(percentEncoded: string) {
+  const decoder = new TextDecoder('windows-1251', { fatal: true, ignoreBOM: false });
+  // https://stackoverflow.com/a/69769015
+  return percentEncoded.replace(
+    /(?:%[0-9A-F]{2})+/g,
+    // @ts-expect-error JS allows typed arrays from string arrays, but TS doesn't know that.
+    (s) => decoder.decode(Uint8Array.from(s.replaceAll('%', ',0x').slice(1).split(','))),
+  );
+}
+
 function normalizeNameAndTitle(name: string | undefined): [string, string] {
   let title = 'Organic Maps';
   if (name) {
-    name = decodeURIComponent(name.replace(/\+|_/g, ' '));
+    name = name.replace(/\+|_/g, ' '); // Convert underscores back to spaces.
+    try {
+      name = decodeURIComponent(name);
+    } catch (ex: any) {
+      try {
+        // There are some cases when coordinates are correct, but the name is not encoded properly, for example:
+        // %DF%F0%EA%EE%E2%F1%EA%EE%E5_%F3%F7%E0%F1%F2%EA%EE%E2%EE%E5_%EB%E5%F1%ED%E8%F7%E5%F1%F2%E2%EE
+        // %C8%EB%EE%E2%E0%E9%F1%EA%EE%E5_%F3%F7%E0%F1%F2%EA%EE%E2%EE%E5_%EB%E5%F1%ED%E8%F7%E5%F1%F2%E2%EE
+        // Looks like vk.com incorrectly uses Windows-1251 to encode some shared links when querying previews.
+        name = fromWindows1251(name);
+      } catch (ex: any) {
+        name = '😃';
+      }
+    }
+
     name = name.replace("'", '&rsquo;'); // To embed in popup.
     title = name + ' | ' + title;
   } else {