From 49c7ccb0cb0078ad07f4f0533f758cd2a7bddee9 Mon Sep 17 00:00:00 2001
From: Lim Chee Aun <cheeaun@gmail.com>
Date: Sat, 7 Sep 2024 17:08:30 +0800
Subject: [PATCH] Handle WEB_DOMAIN for login

Turns out .well-known routes are CORS-enabled
---
 src/locales/en.po   | 22 +++++++++++-----------
 src/pages/login.jsx | 25 ++++++++++++++++++++++++-
 2 files changed, 35 insertions(+), 12 deletions(-)

diff --git a/src/locales/en.po b/src/locales/en.po
index 9b9155f22..088c2d759 100644
--- a/src/locales/en.po
+++ b/src/locales/en.po
@@ -1345,7 +1345,7 @@ msgid "Accounts…"
 msgstr ""
 
 #: src/components/nav-menu.jsx:363
-#: src/pages/login.jsx:166
+#: src/pages/login.jsx:189
 #: src/pages/status.jsx:792
 #: src/pages/welcome.jsx:64
 msgid "Log in"
@@ -1740,7 +1740,7 @@ msgstr ""
 #: src/components/shortcuts-settings.jsx:75
 #: src/components/shortcuts-settings.jsx:84
 #: src/components/shortcuts-settings.jsx:122
-#: src/pages/login.jsx:170
+#: src/pages/login.jsx:193
 msgid "Instance"
 msgstr ""
 
@@ -2368,7 +2368,7 @@ msgstr "Login required."
 
 #: src/compose.jsx:90
 #: src/pages/http-route.jsx:91
-#: src/pages/login.jsx:247
+#: src/pages/login.jsx:270
 msgid "Go home"
 msgstr ""
 
@@ -3052,32 +3052,32 @@ msgstr ""
 msgid "No lists yet."
 msgstr ""
 
-#: src/pages/login.jsx:86
-#: src/pages/login.jsx:99
+#: src/pages/login.jsx:109
+#: src/pages/login.jsx:122
 msgid "Failed to register application"
 msgstr "Failed to register application"
 
-#: src/pages/login.jsx:185
+#: src/pages/login.jsx:208
 msgid "instance domain"
 msgstr "instance domain"
 
-#: src/pages/login.jsx:209
+#: src/pages/login.jsx:232
 msgid "e.g. “mastodon.social”"
 msgstr ""
 
-#: src/pages/login.jsx:220
+#: src/pages/login.jsx:243
 msgid "Failed to log in. Please try again or try another instance."
 msgstr ""
 
-#: src/pages/login.jsx:232
+#: src/pages/login.jsx:255
 msgid "Continue with {selectedInstanceText}"
 msgstr ""
 
-#: src/pages/login.jsx:233
+#: src/pages/login.jsx:256
 msgid "Continue"
 msgstr ""
 
-#: src/pages/login.jsx:241
+#: src/pages/login.jsx:264
 msgid "Don't have an account? Create one!"
 msgstr ""
 
diff --git a/src/pages/login.jsx b/src/pages/login.jsx
index f0a85b42b..32b25e6f8 100644
--- a/src/pages/login.jsx
+++ b/src/pages/login.jsx
@@ -58,9 +58,32 @@ function Login() {
 
   const submitInstance = (instanceURL) => {
     if (!instanceURL) return;
-    store.local.set('instanceURL', instanceURL);
 
     (async () => {
+      // WEB_DOMAIN vs LOCAL_DOMAIN negotiation time
+      // https://docs.joinmastodon.org/admin/config/#web_domain
+      try {
+        const res = await fetch(`https://${instanceURL}/.well-known/host-meta`); // returns XML
+        const text = await res.text();
+        // Parse XML
+        const parser = new DOMParser();
+        const xmlDoc = parser.parseFromString(text, 'text/xml');
+        // Get Link[template]
+        const link = xmlDoc.getElementsByTagName('Link')[0];
+        const template = link.getAttribute('template');
+        const url = URL.parse(template);
+        const { host } = url; // host includes the port
+        if (instanceURL !== host) {
+          console.log(`💫 ${instanceURL} -> ${host}`);
+          instanceURL = host;
+        }
+      } catch (e) {
+        // Silently fail
+        console.error(e);
+      }
+
+      store.local.set('instanceURL', instanceURL);
+
       setUIState('loading');
       try {
         const { client_id, client_secret, vapid_key } =