clipboard

additional/dom-env.js

@@ -441,6 +441,33 @@ function domStopFrameLoop() {
 }
 
 // ─── Clipboard ────────────────────────────────────────────────────────
+//
+// Read path is necessarily a latched buffer: navigator.clipboard.readText
+// is async (Promise) but the C++ Clipboard::GetText signature is
+// synchronous to match the Wayland / Win32 backends. Two feeders keep
+// the cache fresh:
+//
+//   1. A capture-phase `paste` listener on `window` reads
+//      event.clipboardData.getData('text/plain') synchronously — this
+//      covers the standard Ctrl+V flow, where the paste event fires
+//      in the same task as the C++ key handler that will call GetText.
+//   2. Each GetText call also kicks off a navigator.clipboard.readText
+//      in the background. The promise resolves in a later task; the
+//      first call usually still returns the latched paste value (or
+//      nullopt), subsequent calls see the readText result.
+
+let __clipboardCache = null;
+
+window.addEventListener("paste", (event) => {
+    try {
+        const t = event.clipboardData &&
+                  event.clipboardData.getData("text/plain");
+        if (typeof t === "string") __clipboardCache = t;
+    } catch (err) {
+        // Some browsers reject clipboardData access inside non-input
+        // targets; the async readText fallback still has a chance.
+    }
+}, true);
 
 function clipboardSetText(strPtr, strLen) {
     try {
@@ -452,6 +479,19 @@ function clipboardSetText(strPtr, strLen) {
     }
 }
 
+function clipboardGetText() {
+    // Best-effort async refresh. Permission/focus rejections are
+    // expected in non-activated contexts — swallow them so we don't
+    // spam the console on every paste check.
+    if (navigator.clipboard && navigator.clipboard.readText) {
+        navigator.clipboard.readText()
+            .then((t) => { if (typeof t === "string") __clipboardCache = t; })
+            .catch(() => {});
+    }
+    if (__clipboardCache === null) return 0;
+    return __writeUtf8(__clipboardCache);
+}
+
 // ─── History / routing ────────────────────────────────────────────────
 
 function pushState(dataPtr, dataLen, titlePtr, titleLen, urlPtr, urlLen) {
@@ -547,7 +587,7 @@ Object.assign(window.crafter_webbuild_env, {
     domStartFrameLoop, domStopFrameLoop,
 
     // Clipboard
-    clipboardSetText,
+    clipboardSetText, clipboardGetText,
 
     // History
     pushState, addPopStateListener, removePopStateListener, getPathName,