SMP join button: robust clipboard copy with fallback for insecure contexts

src/app/components/apps.tsx

@@ -360,7 +360,7 @@ function SmpApp() {
     motd: null,
     icon: null,
   });
-  const [copied, setCopied] = useState(false);
+  const [copyState, setCopyState] = useState<"idle" | "ok" | "fail">("idle");
 
   useEffect(() => {
     let alive = true;
@@ -389,13 +389,36 @@ function SmpApp() {
   const pending = info.status === "pending";
 
   const copyAddress = async () => {
+    let ok = false;
+    // The async Clipboard API only exists in secure contexts (https / localhost)
+    // and can still reject (no focus, denied permission).
     try {
-      await navigator.clipboard.writeText(address);
-      setCopied(true);
-      window.setTimeout(() => setCopied(false), 1600);
+      if (navigator.clipboard?.writeText) {
+        await navigator.clipboard.writeText(address);
+        ok = true;
+      }
     } catch {
-      /* clipboard unavailable - the address is shown below anyway */
+      ok = false;
     }
+    // Fallback that works in insecure contexts (e.g. LAN over http).
+    if (!ok) {
+      try {
+        const ta = document.createElement("textarea");
+        ta.value = address;
+        ta.setAttribute("readonly", "");
+        ta.style.position = "fixed";
+        ta.style.top = "-1000px";
+        ta.style.opacity = "0";
+        document.body.appendChild(ta);
+        ta.select();
+        ok = document.execCommand("copy");
+        document.body.removeChild(ta);
+      } catch {
+        ok = false;
+      }
+    }
+    setCopyState(ok ? "ok" : "fail");
+    window.setTimeout(() => setCopyState("idle"), 1800);
   };
 
   return (
@@ -445,7 +468,7 @@ function SmpApp() {
 
       <div className="smp-actions">
         <button type="button" className="smp-btn smp-btn-green" onClick={copyAddress}>
-          {copied ? "Address Copied!" : "Join Server"}
+          {copyState === "ok" ? "Address Copied!" : copyState === "fail" ? "Copy failed" : "Join Server"}
         </button>
         <a
           className="smp-btn"
@@ -458,9 +481,11 @@ function SmpApp() {
       </div>
 
       <p className="smp-hint">
-        {copied
+        {copyState === "ok"
           ? "Paste it in Minecraft → Multiplayer → Add Server."
-          : "Join Server copies the address. Add it in Minecraft → Multiplayer → Add Server."}
+          : copyState === "fail"
+            ? `Copy manually: ${address}`
+            : "Join Server copies the address. Add it in Minecraft → Multiplayer → Add Server."}
       </p>
     </div>
   );