Add FUSE external mapping support, BG3/Oblivion Remastered fixes, fomod-plus and NaK integration

FUSE VFS now deploys non-data-dir mod mappings (Paks, OBSE, UE4SS, etc.)
via real symlinks and injects file-level data-dir mappings (plugins.txt,
loadorder.txt) into the VFS tree. Fixes game launches for Oblivion
Remastered (Root Builder path resolution, script extender support) and
BG3 (Wine prefix documents directory, file mapper symlinks on Linux).

Vendors mo2-fomod-plus plugin and NaK crate for FOMOD installer and
game finder/runtime support.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

1 files changed, 120 insertions, 0 deletions

diff --git a/libs/installer_fomod_plus/installer/lib/ViewModels.h b/libs/installer_fomod_plus/installer/lib/ViewModels.h
new file mode 100644
index 0000000..062445a
--- /dev/null
+++ b/libs/installer_fomod_plus/installer/lib/ViewModels.h
@@ -0,0 +1,120 @@
+#pragma once
+
+#include <memory>
+#include <vector>
+
+#include "xml/ModuleConfiguration.h"
+
+
+template <typename T>
+using shared_ptr_list = std::vector<std::shared_ptr<T> >;
+
+
+/*
+--------------------------------------------------------------------------------
+                                Plugins
+--------------------------------------------------------------------------------
+*/
+class PluginViewModel {
+public:
+    PluginViewModel(const std::shared_ptr<Plugin>& plugin_, const bool selected, bool, const int index)
+        : ownIndex(index), selected(selected), enabled(true), manuallySet(false), plugin(plugin_) {}
+
+    void setSelected(const bool selected) { this->selected = selected; }
+    void setEnabled(const bool enabled) { this->enabled = enabled; }
+    [[nodiscard]] std::string getName() const { return plugin ? plugin->name : std::string(); }
+    [[nodiscard]] std::string getDescription() const { return plugin ? plugin->description : std::string(); }
+    [[nodiscard]] std::string getImagePath() const { return plugin ? plugin->image.path : std::string(); }
+    [[nodiscard]] bool isSelected() const { return selected; }
+    [[nodiscard]] bool isEnabled() const { return enabled; }
+    [[nodiscard]] int getOwnIndex() const { return ownIndex; }
+    [[nodiscard]] std::vector<ConditionFlag> getConditionFlags() const { return plugin->conditionFlags.flags; }
+    [[nodiscard]] PluginTypeEnum getCurrentPluginType() const { return currentPluginType; }
+    [[nodiscard]] bool wasManuallySet() const { return manuallySet; }
+
+    void setCurrentPluginType(const PluginTypeEnum type) { currentPluginType = type; }
+    void setStepIndex(const int stepIndex) { this->stepIndex = stepIndex; }
+    void setGroupIndex(const int groupIndex) { this->groupIndex = groupIndex; }
+
+    [[nodiscard]] int getStepIndex() const { return stepIndex; }
+    [[nodiscard]] int getGroupIndex() const { return groupIndex; }
+
+    friend class FomodViewModel;
+    friend class FileInstaller;
+    friend class ConditionTester;
+
+protected:
+    [[nodiscard]] std::shared_ptr<Plugin> getPlugin() const { return plugin; }
+
+private:
+    int ownIndex;
+    bool selected;
+    bool enabled;
+    bool manuallySet;
+    PluginTypeEnum currentPluginType = PluginTypeEnum::UNKNOWN;
+    std::shared_ptr<Plugin> plugin;
+
+    int stepIndex{ -1 };
+    int groupIndex{ -1 };
+};
+
+/*
+--------------------------------------------------------------------------------
+                                Groups
+--------------------------------------------------------------------------------
+*/
+class GroupViewModel {
+public:
+    GroupViewModel(const std::shared_ptr<Group>& group_, const shared_ptr_list<PluginViewModel>& plugins,
+        const int index, const int stepIndex)
+        : plugins(plugins), group(group_), ownIndex(index), stepIndex(stepIndex) {}
+
+    void addPlugin(const std::shared_ptr<PluginViewModel>& plugin) { plugins.emplace_back(plugin); }
+
+    [[nodiscard]] std::string getName() const { return group->name; }
+    [[nodiscard]] GroupTypeEnum getType() const { return group->type; }
+    [[nodiscard]] const shared_ptr_list<PluginViewModel>& getPlugins() const { return plugins; }
+    [[nodiscard]] int getOwnIndex() const { return ownIndex; }
+    [[nodiscard]] int getStepIndex() const { return stepIndex; }
+
+private:
+    shared_ptr_list<PluginViewModel> plugins;
+    std::shared_ptr<Group> group;
+    int ownIndex;
+    int stepIndex;
+};
+
+/*
+--------------------------------------------------------------------------------
+                                Steps
+--------------------------------------------------------------------------------
+*/
+class StepViewModel {
+public:
+    StepViewModel(const std::shared_ptr<InstallStep>& installStep_, const shared_ptr_list<GroupViewModel>& groups,
+        const int index)
+        : installStep(installStep_), groups(groups), ownIndex(index) {}
+
+    [[nodiscard]] CompositeDependency& getVisibilityConditions() const { return installStep->visible; }
+    [[nodiscard]] std::string getName() const { return installStep->name; }
+    [[nodiscard]] const shared_ptr_list<GroupViewModel>& getGroups() const { return groups; }
+    [[nodiscard]] int getOwnIndex() const { return ownIndex; }
+    [[nodiscard]] bool getHasVisited() const { return visited; }
+    void setVisited(const bool visited) { this->visited = visited; }
+
+private:
+    bool visited{ false };
+    std::shared_ptr<InstallStep> installStep;
+    shared_ptr_list<GroupViewModel> groups;
+    int ownIndex;
+};
+
+
+/*
+--------------------------------------------------------------------------------
+                            Outbound Types
+--------------------------------------------------------------------------------
+*/
+using StepRef   = const std::shared_ptr<StepViewModel>&;
+using GroupRef  = const std::shared_ptr<GroupViewModel>&;
+using PluginRef = const std::shared_ptr<PluginViewModel>&;