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, 305 insertions, 0 deletions

diff --git a/libs/installer_fomod_plus/share/xml/ModuleConfiguration.h b/libs/installer_fomod_plus/share/xml/ModuleConfiguration.h
new file mode 100644
index 0000000..a0a017b
--- /dev/null
+++ b/libs/installer_fomod_plus/share/xml/ModuleConfiguration.h
@@ -0,0 +1,305 @@
+#pragma once
+
+#include <iostream>
+#include <optional>
+#include <pugixml.hpp>
+#include <qstring.h>
+#include <string>
+#include <vector>
+
+class XmlDeserializable {
+public:
+    virtual ~XmlDeserializable() = default;
+
+    virtual bool deserialize(pugi::xml_node& node) = 0;
+
+protected:
+    XmlDeserializable() = default;
+};
+
+enum GroupTypeEnum {
+    SelectAny,
+    SelectAll,
+    SelectExactlyOne,
+    SelectAtMostOne,
+    SelectAtLeastOne
+};
+
+enum class OperatorTypeEnum {
+    AND,
+    OR
+};
+
+enum class OrderTypeEnum {
+    Explicit,
+    Ascending,
+    Descending
+};
+
+enum class FileDependencyTypeEnum {
+    Missing,
+    Inactive,
+    Active,
+    UNKNOWN_STATE
+};
+
+template <typename T>
+class OrderedContents {
+public:
+    OrderTypeEnum order;
+
+    OrderedContents() : order(OrderTypeEnum::Ascending) {}
+    explicit OrderedContents(const OrderTypeEnum orderType): order(orderType) {}
+
+    template <typename Accessor>
+    bool compare(const T& a, const T& b, Accessor accessor) const
+    {
+        switch (order) {
+        case OrderTypeEnum::Ascending:
+            return accessor(a) < accessor(b);
+        case OrderTypeEnum::Descending:
+            return accessor(a) > accessor(b);
+        case OrderTypeEnum::Explicit:
+        default:
+            return false; // No sorting for explicit order
+        }
+    }
+};
+
+enum class PluginTypeEnum {
+    Recommended,
+    Required,
+    Optional,
+    NotUsable,
+    CouldBeUsable,
+    UNKNOWN
+};
+
+
+inline std::ostream& operator<<(std::ostream& os, const PluginTypeEnum& type)
+{
+    switch (type) {
+    case PluginTypeEnum::Recommended:
+        os << "Recommended";
+        break;
+    case PluginTypeEnum::Required:
+        os << "Required";
+        break;
+    case PluginTypeEnum::Optional:
+        os << "Optional";
+        break;
+    case PluginTypeEnum::NotUsable:
+        os << "NotUsable";
+        break;
+    case PluginTypeEnum::CouldBeUsable:
+        os << "CouldBeUsable";
+        break;
+    default: ;
+    }
+    return os;
+}
+
+class PluginType final : public XmlDeserializable {
+public:
+    PluginTypeEnum name = PluginTypeEnum::Optional; // sane default
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class FileDependency final : public XmlDeserializable {
+public:
+    std::string file;
+    FileDependencyTypeEnum state = FileDependencyTypeEnum::UNKNOWN_STATE;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class FlagDependency final : public XmlDeserializable {
+public:
+    std::string flag;
+    std::string value;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class GameDependency final : public XmlDeserializable {
+public:
+    std::string version;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class CompositeDependency final : public XmlDeserializable {
+public:
+    std::vector<FileDependency> fileDependencies;
+    std::vector<FlagDependency> flagDependencies;
+    std::vector<GameDependency> gameDependencies;
+    std::vector<CompositeDependency> nestedDependencies;
+    OperatorTypeEnum operatorType = OperatorTypeEnum::AND; // safest default.
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class DependencyPattern final : public XmlDeserializable {
+public:
+    CompositeDependency dependencies;
+    PluginTypeEnum type;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+
+class DependencyPatternList final : public XmlDeserializable {
+public:
+    std::vector<DependencyPattern> patterns;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class DependencyPluginType final : public XmlDeserializable {
+public:
+    std::optional<PluginTypeEnum> defaultType;
+    DependencyPatternList patterns;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class TypeDescriptor final : public XmlDeserializable {
+public:
+    DependencyPluginType dependencyType;
+    PluginTypeEnum type;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class Image final : public XmlDeserializable {
+public:
+    std::string path;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class HeaderImage final : public XmlDeserializable {
+public:
+    std::string path;
+    bool showImage;
+    bool showFade;
+    int height;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class File final : public XmlDeserializable {
+public:
+    std::string source;
+    std::optional<std::string> destination;
+    int priority{ 0 };
+    bool isFolder;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+
+class FileList final : public XmlDeserializable {
+public:
+    std::vector<File> files;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class ConditionalFileInstallPattern final : public XmlDeserializable {
+public:
+    CompositeDependency dependencies;
+    FileList files;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+// <flag name="2">On</flag>
+class ConditionFlag final : public XmlDeserializable {
+public:
+    std::string name;
+    std::string value;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class ConditionFlagList final : public XmlDeserializable {
+public:
+    std::vector<ConditionFlag> flags;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class Plugin final : public XmlDeserializable {
+public:
+    std::string description;
+    Image image;
+    TypeDescriptor typeDescriptor;
+    std::string name;
+    ConditionFlagList conditionFlags;
+    FileList files;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class PluginList final : public XmlDeserializable, public OrderedContents<Plugin> {
+public:
+    std::vector<Plugin> plugins;
+    OrderTypeEnum order;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class Group final : public XmlDeserializable {
+public:
+    PluginList plugins;
+    std::string name;
+    GroupTypeEnum type;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class GroupList final : public XmlDeserializable, public OrderedContents<Group> {
+public:
+    std::vector<Group> groups;
+    OrderTypeEnum order;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class InstallStep final : public XmlDeserializable {
+public:
+    CompositeDependency visible;
+    GroupList optionalFileGroups;
+    std::string name;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class ConditionalFileInstall final : public XmlDeserializable {
+public:
+    std::vector<ConditionalFileInstallPattern> patterns;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class StepList final : public XmlDeserializable, public OrderedContents<InstallStep> {
+public:
+    std::vector<InstallStep> installSteps;
+    OrderTypeEnum order;
+
+    bool deserialize(pugi::xml_node& node) override;
+};
+
+class ModuleConfiguration {
+public:
+    std::string moduleName;
+    HeaderImage moduleImage;
+    CompositeDependency moduleDependencies;
+    FileList requiredInstallFiles;
+    StepList installSteps;
+    ConditionalFileInstall conditionalFileInstalls;
+
+    bool deserialize(const QString& filePath);
+};
\ No newline at end of file