URL protocol modpack import for any encoded URL (#4990)

launcher/ui/MainWindow.cpp

@@ -48,6 +48,7 @@
 #include <QDir>
 #include <QFileInfo>
 #include <QUrl>
+#include <QUrlQuery>
 #include <QVariant>
 
 #include <QAction>
@@ -940,6 +941,11 @@ void MainWindow::processURLs(QList<QUrl> urls)
         QMap<QString, QString> extra_info;
         QUrl local_url;
         if (!url.isLocalFile()) {  // download the remote resource and identify
+
+            const bool isExternalURLImport =
+                (url.host().toLower() == "import") ||
+                (url.path().startsWith("/import", Qt::CaseInsensitive));
+
             QUrl dl_url;
             if (url.scheme() == "curseforge") {
                 // need to find the download link for the modpack / resource
@@ -993,7 +999,7 @@ void MainWindow::processURLs(QList<QUrl> urls)
                     dlUrlDialod.execWithTask(job.get());
                 }
 
-            } else if (url.scheme() == BuildConfig.LAUNCHER_APP_BINARY_NAME) {
+            } else if (url.scheme() == BuildConfig.LAUNCHER_APP_BINARY_NAME && !isExternalURLImport) {
                 QVariantMap receivedData;
                 const QUrlQuery query(url.query());
                 const auto items = query.queryItems();
@@ -1001,6 +1007,78 @@ void MainWindow::processURLs(QList<QUrl> urls)
                     receivedData.insert(it->first, it->second);
                 emit APPLICATION->oauthReplyRecieved(receivedData);
                 continue;
+            } else if ((url.scheme() == "prismlauncher" || url.scheme() == BuildConfig.LAUNCHER_APP_BINARY_NAME) 
+                        && isExternalURLImport) {
+                // PrismLauncher URL protocol modpack import
+                // works for any prism fork
+                // preferred import format: prismlauncher://import?url=ENCODED
+                const auto host = url.host().toLower();
+                const auto path = url.path(); 
+
+                QString encodedTarget;
+
+                {
+                    QUrlQuery query(url);
+                    const auto values = query.allQueryItemValues("url");
+                    if (!values.isEmpty()) {
+                        encodedTarget = values.first();
+                    }
+                }
+
+                // alternative import format: prismlauncher://import/ENCODED
+                if (encodedTarget.isEmpty()) {
+
+                    QString p = path;
+
+                    if (p.startsWith("/import/", Qt::CaseInsensitive)) {
+                        p = p.mid(QString("/import/").size());
+                    } else if (host == "import" && p.startsWith("/")) {
+                        p = p.mid(1);
+                    }
+
+                    if (!p.isEmpty() && p != "/import") {
+                        encodedTarget = p;
+                    }
+                }
+
+                if (encodedTarget.isEmpty()) {
+                    CustomMessageBox::selectable(
+                        this,
+                        tr("Error"),
+                        tr("Invalid import link: missing 'url' parameter."),
+                        QMessageBox::Critical
+                    )->show();
+                    continue;
+                }
+
+                const QString decodedStr = QUrl::fromPercentEncoding(encodedTarget.toUtf8()).trimmed();
+
+                QUrl target = QUrl::fromUserInput(decodedStr);
+
+                // Validate: only allow http(s)
+                if (!target.isValid() || (target.scheme() != "https" && target.scheme() != "http")) {
+                    CustomMessageBox::selectable(
+                        this,
+                        tr("Error"),
+                        tr("Invalid import link: URL must be http(s)."),
+                        QMessageBox::Critical
+                    )->show();
+                    continue;
+                }
+
+                const auto res = QMessageBox::question(
+                    this,
+                    tr("Install modpack"),
+                    tr("Do you want to download and import a modpack from:\n%1\n\nURL:\n%2")
+                        .arg(target.host(), target.toString()),
+                    QMessageBox::Yes | QMessageBox::No,
+                    QMessageBox::Yes
+                );
+                if (res != QMessageBox::Yes) {
+                    continue;
+                }
+            
+                dl_url = target;
             } else {
                 dl_url = url;
             }

program_info/win_install.nsi.in

@@ -397,6 +397,10 @@ Section "@Launcher_DisplayName@"
   WriteRegStr HKCU Software\Classes\@Launcher_APP_BINARY_NAME@ "URL Protocol" ""
   WriteRegStr HKCU Software\Classes\@Launcher_APP_BINARY_NAME@\shell\open\command "" '"$INSTDIR\@Launcher_APP_BINARY_NAME@.exe" "%1"'
 
+  ; Write the URL Handler into registry for prismlauncher import
+  WriteRegStr HKCU Software\Classes\prismlauncher "URL Protocol" ""
+  WriteRegStr HKCU Software\Classes\prismlauncher\shell\open\command "" '"$INSTDIR\@Launcher_APP_BINARY_NAME@.exe" "%1"'
+
   ; Write the uninstall keys for Windows
   ; https://learn.microsoft.com/en-us/windows/win32/msi/uninstall-registry-key
   ${GetParameters} $R0