qt: fix uri scheme handling on macOS

In Qt 6.8, the way custom uri schemes are handled on macOS changed.

The commit that changed it is
qt/qtbase@664c7ff. Before,
the URL would be emitted as a FileOpen event with a QFileOpenEvent
object. After this change, it is dispatched to QDesktopServices.

Before, QDesktopServices would only be used to register custom schemes
while the app was running, but now it also is used when the app is
launched with by a URI click (provided the Info.plist entry for it is there
of course).

Author: benma

frontends/qt/BitBox.pro

@@ -59,9 +59,10 @@ unix:!macx {
 
 SOURCES += \
         main.cpp \
-        filedialog.cpp
+        filedialog.cpp \
+        urlhandler.cpp
 
-HEADERS += libserver.h webclass.h filedialog.h
+HEADERS += libserver.h webclass.h filedialog.h urlhandler.h
 
 unix:macx {
     CONFIG += sdk_no_version_check

frontends/qt/main.cpp

@@ -38,6 +38,7 @@
 #include <QSystemTrayIcon>
 #include <QMessageBox>
 #include <QtGlobal>
+#include <QtSystemDetection>
 #if defined(_WIN32)
 #if QT_VERSION_MAJOR >= 6
 #include <private/qguiapplication_p.h>
@@ -55,6 +56,7 @@
 #include "filedialog.h"
 #include "libserver.h"
 #include "webclass.h"
+#include "urlhandler.h"
 
 #define APPNAME "BitBoxApp"
 
@@ -85,25 +87,6 @@ class BitBoxApp : public SingleApplication
         Mode::User | Mode::SecondaryNotification | Mode::ExcludeAppVersion | Mode::ExcludeAppPath)
     {
     }
-
-#if defined(Q_OS_MACOS)
-    bool event(QEvent *event) override
-    {
-        if (event->type() == QEvent::FileOpen) {
-            QFileOpenEvent* openEvent = static_cast<QFileOpenEvent*>(event);
-            if (!openEvent->url().isEmpty()) {
-                // This is only supported on macOS and is used to handle URIs that are opened with
-                // the BitBoxApp, such as "aopp:..." links. The event is received and handled both
-                // if the BitBoxApp is launched and also when it is already running, in which case
-                // it is brought to the foreground automatically.
-
-                handleURI(openEvent->url().toString().toUtf8().constData());
-            }
-        }
-
-        return QApplication::event(event);
-    }
-#endif
 };
 
 class WebEnginePage : public QWebEnginePage {
@@ -318,6 +301,12 @@ int main(int argc, char *argv[])
     }
 
     BitBoxApp a(argc, argv);
+    // The URI scheme handler for aopp is handled via OS events on macOS. The other platforms invoke
+    // the process with the uri as a command line param.
+#if defined(Q_OS_MACOS)
+    UrlHandler url_handler;
+    url_handler.setup();
+#endif
     // These three are part of the SingleApplication instance ID - if changed, the user should close
     // th existing app before launching the new one.
     // See https://github.com/BitBoxSwiss/SingleApplication/blob/c557da5d0cb63b8002c1ba99ec18f257620009b1/singleapplication_p.cpp#L135-L137

frontends/qt/urlhandler.cpp

@@ -0,0 +1,30 @@
+// Copyright 2025 Shift Crypto AG
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "urlhandler.h"
+#include "libserver.h"
+
+#include <iostream>
+#include <QDesktopServices>
+
+UrlHandler::UrlHandler(QObject *parent) : QObject(parent) {
+}
+
+void UrlHandler::setup() {
+    QDesktopServices::setUrlHandler("aopp", this, "handleUrlSlot");
+}
+
+void UrlHandler::handleUrlSlot(const QUrl &url) {
+    handleURI(url.toString().toUtf8().constData());
+}

frontends/qt/urlhandler.h

@@ -0,0 +1,33 @@
+// Copyright 2025 Shift Crypto AG
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef URLHANDLER_H
+#define URLHANDLER_H
+
+#include <QObject>
+#include <QUrl>
+
+class UrlHandler : public QObject {
+    Q_OBJECT
+
+public:
+    UrlHandler(QObject *parent = nullptr);
+
+    void setup();
+
+public slots:
+    void handleUrlSlot(const QUrl &url);
+};
+
+#endif // URLHANDLER_H