Create a promise wrapper for C++ and port existing uses

Currently, to use a promise from C++ we either have to use an ASM block
(which does not work well with dynamic linking) or declare exports in
the EMSCRIPTEN_BINDINGS block, which is cumbersome and cannot be chained.
This solution makes it easy to use js promises by introducing the
WebPromiseManager which dispatches callbacks to appropriate callers when
available.
This is a preliminary patch for FileSystem support, which will heavily
use async APIs.

Task-number: QTBUG-99611
Change-Id: I368a8f173027eaa883a9ca18d0ea6a3e99b86071
Reviewed-by: Morten Johan Sørvig <morten.sorvig@qt.io>

1 files changed, 11 insertions, 98 deletions

diff --git a/src/plugins/platforms/wasm/qwasmclipboard.cpp b/src/plugins/platforms/wasm/qwasmclipboard.cpp
index 88043ba092..99f3e61155 100644
--- a/src/plugins/platforms/wasm/qwasmclipboard.cpp
+++ b/src/plugins/platforms/wasm/qwasmclipboard.cpp
@@ -19,83 +19,6 @@
 QT_BEGIN_NAMESPACE
 using namespace emscripten;
 
-static void pasteClipboardData(emscripten::val format, emscripten::val dataPtr)
-{
-    QString formatString = QWasmString::toQString(format);
-    QByteArray dataArray = QByteArray::fromStdString(dataPtr.as<std::string>());
-
-    QMimeData *mMimeData = new QMimeData;
-    mMimeData->setData(formatString, dataArray);
-
-    QWasmClipboard::qWasmClipboardPaste(mMimeData);
-//    QWasmIntegration::get()->getWasmClipboard()->isPaste = false;
-}
-
-static void qClipboardPasteResolve(emscripten::val blob)
-{
-    // read Blob here
-
-    auto fileReader = std::make_shared<qstdweb::FileReader>();
-    auto _blob = qstdweb::Blob(blob);
-    QString formatString = QString::fromStdString(_blob.type());
-
-    fileReader->readAsArrayBuffer(_blob);
-    char *chunkBuffer = nullptr;
-    qstdweb::ArrayBuffer result = fileReader->result();
-    qstdweb::Uint8Array(result).copyTo(chunkBuffer);
-    QMimeData *mMimeData = new QMimeData;
-    mMimeData->setData(formatString, chunkBuffer);
-    QWasmClipboard::qWasmClipboardPaste(mMimeData);
-}
-
-static void qClipboardPromiseResolve(emscripten::val clipboardItems)
-{
-    int itemsCount = clipboardItems["length"].as<int>();
-
-    for (int i = 0; i < itemsCount; i++) {
-        int typesCount = clipboardItems[i]["types"]["length"].as<int>(); // ClipboardItem
-
-        std::string mimeFormat = clipboardItems[i]["types"][0].as<std::string>();
-
-        if (mimeFormat.find(std::string("text")) != std::string::npos) {
-            // simple val object, no further processing
-
-            val navigator = val::global("navigator");
-            val textPromise = navigator["clipboard"].call<val>("readText");
-            val readTextResolve = val::global("Module")["qtClipboardTextPromiseResolve"];
-            textPromise.call<val>("then", readTextResolve);
-
-        } else {
-            //  binary types require additional processing
-            for (int j = 0; j < typesCount; j++) {
-                val pasteResolve = emscripten::val::module_property("qtClipboardPasteResolve");
-                val pasteException = emscripten::val::module_property("qtClipboardPromiseException");
-
-                // get the blob
-                clipboardItems[i]
-                        .call<val>("getType", clipboardItems[i]["types"][j])
-                        .call<val>("then", pasteResolve)
-                        .call<val>("catch", pasteException);
-            }
-        }
-    }
-}
-
-static void qClipboardCopyPromiseResolve(emscripten::val something)
-{
-    Q_UNUSED(something)
-    qWarning() << "copy succeeeded";
-}
-
-
-static emscripten::val qClipboardPromiseException(emscripten::val something)
-{
-    qWarning() << "clipboard error"
-               << QString::fromStdString(something["name"].as<std::string>())
-            << QString::fromStdString(something["message"].as<std::string>());
-    return something;
-}
-
 static void commonCopyEvent(val event)
 {
     QMimeData *_mimes = QWasmIntegration::get()->getWasmClipboard()->mimeData(QClipboard::Clipboard);
@@ -215,24 +138,10 @@ static void qClipboardPasteTo(val dataTransfer)
     QWasmIntegration::get()->getWasmClipboard()->m_isListener = false;
 }
 
-static void qClipboardTextPromiseResolve(emscripten::val clipdata)
-{
-    pasteClipboardData(emscripten::val("text/plain"), clipdata);
-}
-
 EMSCRIPTEN_BINDINGS(qtClipboardModule) {
-    function("qtPasteClipboardData", &pasteClipboardData);
-
-    function("qtClipboardTextPromiseResolve", &qClipboardTextPromiseResolve);
-    function("qtClipboardPromiseResolve", &qClipboardPromiseResolve);
-
-    function("qtClipboardCopyPromiseResolve", &qClipboardCopyPromiseResolve);
-    function("qtClipboardPromiseException", &qClipboardPromiseException);
-
     function("qtClipboardCutTo", &qClipboardCutTo);
     function("qtClipboardCopyTo", &qClipboardCopyTo);
     function("qtClipboardPasteTo", &qClipboardPasteTo);
-    function("qtClipboardPasteResolve", &qClipboardPasteResolve);
 }
 
 QWasmClipboard::QWasmClipboard() :
@@ -419,14 +328,18 @@ void QWasmClipboard::writeToClipboardApi()
         // break;
     }
 
-    val copyResolve = emscripten::val::module_property("qtClipboardCopyPromiseResolve");
-    val copyException = emscripten::val::module_property("qtClipboardPromiseException");
-
     val navigator = val::global("navigator");
-    navigator["clipboard"]
-            .call<val>("write", clipboardWriteArray)
-            .call<val>("then", copyResolve)
-            .call<val>("catch", copyException);
+
+    qstdweb::Promise::make(
+        navigator["clipboard"], "write",
+        {
+            .catchFunc = [](emscripten::val error) {
+                qWarning() << "clipboard error"
+                    << QString::fromStdString(error["name"].as<std::string>())
+                    << QString::fromStdString(error["message"].as<std::string>());
+            }
+        },
+        clipboardWriteArray);
 }
 
 void QWasmClipboard::writeToClipboard(const QMimeData *data)