feat(RD): add resource pack downloader

Signed-off-by: flow <flowlnlnln@gmail.com>

launcher/ui/pages/modplatform/ResourcePackModel.h

@@ -0,0 +1,39 @@
+#pragma once
+
+#include <QAbstractListModel>
+
+#include "BaseInstance.h"
+
+#include "modplatform/ModIndex.h"
+
+#include "ui/pages/modplatform/ResourceModel.h"
+
+class Version;
+
+namespace ResourceDownload {
+
+class ResourcePackResourceModel : public ResourceModel {
+    Q_OBJECT
+
+   public:
+    ResourcePackResourceModel(BaseInstance const&, ResourceAPI*);
+
+    /* Ask the API for more information */
+    void searchWithTerm(const QString& term, unsigned int sort);
+
+    void loadIndexedPack(ModPlatform::IndexedPack&, QJsonObject&) override = 0;
+    void loadExtraPackInfo(ModPlatform::IndexedPack&, QJsonObject&) override = 0;
+    void loadIndexedPackVersions(ModPlatform::IndexedPack&, QJsonArray&) override = 0;
+
+   public slots:
+    ResourceAPI::SearchArgs createSearchArguments() override;
+    ResourceAPI::VersionSearchArgs createVersionsArguments(QModelIndex&) override;
+    ResourceAPI::ProjectInfoArgs createInfoArguments(QModelIndex&) override;
+
+   protected:
+    const BaseInstance& m_base_instance;
+
+    auto documentToArray(QJsonDocument& obj) const -> QJsonArray override = 0;
+};
+
+}  // namespace ResourceDownload