$ show Monitor221hz/Pandora-Behaviour-Engine-Plus
Pandora Behaviour Engine Plus is a C# desktop application (Avalonia UI) for patching Skyrim's Havok animation behavior files (.hkx). It parses mod-provided patch instructions in Nemesis, FNIS, and Pandora XML formats, then injects changes into base behavior graphs to support custom animations. The architecture follows a modular DI pattern with services for mod detection, plugin loading, path management, and engine execution. Key components include a state machine for engine lifecycle, a plugin system for extensibility, and a set of reusable change types (IPackFileChange) for applying edits to Havok packfiles. The application provides both a GUI and a CLI mode, and includes extensive test data (hundreds of patch files) for validation. While the core patching logic is solid and well-structured, there are signs of technical drift (preview .NET target, some dead code) and the large test data set presents maintenance overhead. Overall, it is a strong, professional-grade modding tool with reusable patterns for behavior graph manipulation.
The LLM identified 4 files worth highlighting for reuse:
Defines a change set (PackFileChangeSet) and a set of IPackFileChange implementations (ReplaceElementChange, InsertTextChange, AppendElementChange, etc.) that represent atomic modifications to Havok behavior files. These are isolated, self-contained objects that can be applied to any HKX packfile, making them reusable across different patching formats. The pattern is clean and could be extracted into a generic library for applying XML-like diffs.
A standalone implementation of CRC32 used for encoding animation paths in Skyrim's animation set data. It has no internal dependencies and could be reused in any .NET project requiring CRC32 computation. The implementation is minimal and efficient.
An interface IModInfoProvider with concrete implementations (FileBasedModInfoProvider, NemesisModInfoProvider, PandoraModInfoProvider) that abstracts mod information retrieval. This pattern decouples mod discovery from the engine and can be extended for new mod sources. The interface is minimal and the implementations are self-contained, making the provider pattern reusable in other applications that need to load data from various sources.
Implements a finite state machine for the engine lifecycle (states: Idle, Running, Completed, Error, Cancelled) with transitions triggered by events. Uses ReactiveUI observables for state change notification. The state machine is well-encapsulated and could be reused in any .NET application requiring a deterministic state machine with observable state changes.