redo event emitter

Author: Saadnajmi

packages/react-native/ReactCommon/react/renderer/components/view/platform/macos/react/renderer/components/view/HostPlatformViewEventEmitter.cpp

@@ -52,7 +52,8 @@ void HostPlatformViewEventEmitter::onKeyUp(const KeyEvent& keyEvent) const {
 
 #pragma mark - Mouse Events
 
-static jsi::Value mouseEventPayload(jsi::Runtime& runtime, const MouseEvent& event) {
+// Returns an Object instead of value as we read and modify it in dragEventPayload.
+static jsi::Object mouseEventPayload(jsi::Runtime& runtime, const MouseEvent& event) {
   auto payload = jsi::Object(runtime);
   payload.setProperty(runtime, "clientX", event.clientX);
   payload.setProperty(runtime, "clientY", event.clientY);
@@ -77,4 +78,74 @@ void HostPlatformViewEventEmitter::onMouseLeave(const MouseEvent& mouseEvent) co
   });
 }
 
+#pragma mark - Drag and Drop Events
+
+static jsi::Value dataTransferPayload(
+    jsi::Runtime& runtime,
+    const std::vector<DataTransferItem>& dataTransferItems) {
+  auto filesArray = jsi::Array(runtime, dataTransferItems.size());
+  auto itemsArray = jsi::Array(runtime, dataTransferItems.size());
+  auto typesArray = jsi::Array(runtime, dataTransferItems.size());
+  int i = 0;
+  for (const auto& transferItem : dataTransferItems) {
+    auto fileObject = jsi::Object(runtime);
+    fileObject.setProperty(runtime, "name", transferItem.name);
+    fileObject.setProperty(runtime, "type", transferItem.type);
+    fileObject.setProperty(runtime, "uri", transferItem.uri);
+    if (transferItem.size.has_value()) {
+      fileObject.setProperty(runtime, "size", *transferItem.size);
+    }
+    if (transferItem.width.has_value()) {
+      fileObject.setProperty(runtime, "width", *transferItem.width);
+    }
+    if (transferItem.height.has_value()) {
+      fileObject.setProperty(runtime, "height", *transferItem.height);
+    }
+    filesArray.setValueAtIndex(runtime, i, fileObject);
+
+    auto itemObject = jsi::Object(runtime);
+    itemObject.setProperty(runtime, "kind", transferItem.kind);
+    itemObject.setProperty(runtime, "type", transferItem.type);
+    itemsArray.setValueAtIndex(runtime, i, itemObject);
+
+    typesArray.setValueAtIndex(runtime, i, transferItem.type);
+    i++;
+  }
+
+  auto dataTransferObject = jsi::Object(runtime);
+  dataTransferObject.setProperty(runtime, "files", filesArray);
+  dataTransferObject.setProperty(runtime, "items", itemsArray);
+  dataTransferObject.setProperty(runtime, "types", typesArray);
+
+  return dataTransferObject;
+}
+
+static jsi::Value dragEventPayload(
+    jsi::Runtime& runtime,
+    const DragEvent& event) {
+  auto payload = mouseEventPayload(runtime, event);
+  auto dataTransferObject =
+      dataTransferPayload(runtime, event.dataTransferItems);
+  payload.setProperty(runtime, "dataTransfer", dataTransferObject);
+  return payload;
+}
+
+void HostPlatformViewEventEmitter::onDragEnter(DragEvent const& dragEvent) const {
+  dispatchEvent("dragEnter", [dragEvent](jsi::Runtime &runtime) {
+    return dragEventPayload(runtime, dragEvent);
+  });
+}
+
+void HostPlatformViewEventEmitter::onDragLeave(DragEvent const& dragEvent) const {
+  dispatchEvent("dragLeave", [dragEvent](jsi::Runtime &runtime) {
+    return dragEventPayload(runtime, dragEvent);
+  });
+}
+
+void HostPlatformViewEventEmitter::onDrop(DragEvent const& dragEvent) const {
+  dispatchEvent("drop", [dragEvent](jsi::Runtime &runtime) {
+    return dragEventPayload(runtime, dragEvent);
+  });
+}
+
 } // namespace facebook::react