From d61f2b7ab0715c63f6bb534e6e72f89cd04c6994 Mon Sep 17 00:00:00 2001
From: David Montero Crespo <davidmonterocrespo24@gmail.com>
Date: Mon, 23 Mar 2026 15:06:49 -0300
Subject: [PATCH] feat: update SEO handling by dynamically setting canonical
 links and exclude auth pages from sitemap

---
 frontend/index.html          |  2 +-
 frontend/public/sitemap.xml  | 14 +-------------
 frontend/src/utils/useSEO.ts | 19 +++++++++++++++++--
 3 files changed, 19 insertions(+), 16 deletions(-)

diff --git a/frontend/index.html b/frontend/index.html
index 780f896..ed3b343 100644
--- a/frontend/index.html
+++ b/frontend/index.html
@@ -13,7 +13,7 @@
     <meta name="keywords" content="arduino emulator, arduino simulator, arduino simulator free, avr8 emulator, avr simulator, atmega328p simulator, atmega2560 simulator, attiny85 simulator, arduino uno simulator, arduino mega simulator, arduino nano simulator, rp2040 emulator, raspberry pi pico simulator, esp32 emulator, esp32 simulator, esp32-c3 simulator, esp32-s3 emulator, risc-v simulator, ch32v003, raspberry pi 3 emulator, wokwi alternative, arduino ide browser, arduino online, electronics simulator, velxio" />
     <meta name="author" content="David Montero Crespo" />
     <meta name="robots" content="index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1" />
-    <link rel="canonical" href="https://velxio.dev/" />
+    <!-- canonical is set dynamically per-route by the useSEO hook -->
 
     <!-- Google Search Console verification — replace token after verifying in Search Console -->
     <!-- <meta name="google-site-verification" content="REPLACE_WITH_YOUR_VERIFICATION_TOKEN" /> -->
diff --git a/frontend/public/sitemap.xml b/frontend/public/sitemap.xml
index e899f2b..6b6229f 100644
--- a/frontend/public/sitemap.xml
+++ b/frontend/public/sitemap.xml
@@ -129,18 +129,6 @@
     <priority>0.85</priority>
   </url>
 
-  <url>
-    <loc>https://velxio.dev/login</loc>
-    <lastmod>2026-03-06</lastmod>
-    <changefreq>yearly</changefreq>
-    <priority>0.3</priority>
-  </url>
-
-  <url>
-    <loc>https://velxio.dev/register</loc>
-    <lastmod>2026-03-06</lastmod>
-    <changefreq>yearly</changefreq>
-    <priority>0.3</priority>
-  </url>
+  <!-- Auth pages intentionally excluded from sitemap (not for indexing) -->
 
 </urlset>
diff --git a/frontend/src/utils/useSEO.ts b/frontend/src/utils/useSEO.ts
index 8492e2f..88ffea1 100644
--- a/frontend/src/utils/useSEO.ts
+++ b/frontend/src/utils/useSEO.ts
@@ -47,6 +47,17 @@ export function useSEO({ title, description, url, ogImage, jsonLd }: SEOMeta) {
     const origTwDesc    = get(twDescEl);
     const origCanonical = canonicalEl?.getAttribute('href') ?? '';
 
+    // If no <link rel="canonical"> exists yet, create one so each SPA route
+    // gets its own canonical (avoids all routes appearing to point back to /).
+    let createdCanonical = false;
+    let activeCanonical: HTMLLinkElement | null = canonicalEl as HTMLLinkElement | null;
+    if (!activeCanonical) {
+      activeCanonical = document.createElement('link') as HTMLLinkElement;
+      activeCanonical.rel = 'canonical';
+      document.head.appendChild(activeCanonical);
+      createdCanonical = true;
+    }
+
     // Apply
     document.title = title;
     set(descEl, description);
@@ -56,7 +67,7 @@ export function useSEO({ title, description, url, ogImage, jsonLd }: SEOMeta) {
     if (ogImage) set(ogImgEl, ogImage);
     set(twTitleEl, title);
     set(twDescEl, description);
-    canonicalEl?.setAttribute('href', url);
+    activeCanonical.setAttribute('href', url);
 
     // Inject JSON-LD once (module-level constants don't change)
     if (jsonLd && !scriptRef.current) {
@@ -77,7 +88,11 @@ export function useSEO({ title, description, url, ogImage, jsonLd }: SEOMeta) {
       if (ogImage) set(ogImgEl, origOgImg);
       set(twTitleEl, origTwTitle);
       set(twDescEl, origTwDesc);
-      canonicalEl?.setAttribute('href', origCanonical);
+      if (createdCanonical && activeCanonical && document.head.contains(activeCanonical)) {
+        document.head.removeChild(activeCanonical);
+      } else {
+        activeCanonical?.setAttribute('href', origCanonical);
+      }
       if (scriptRef.current) {
         document.head.removeChild(scriptRef.current);
         scriptRef.current = null;