gregWiki/docs/reference/greg-hooks-registry.md

id, title, slug, description

id	title	slug	description
greg-hooks-registry	greg.* hooks registry (IL2CPP)	/reference/greg-hooks-registry	greg_hooks.json, Harmony hook sources under gregCore, regeneration from Il2Cpp unpack, and overlap with Rust bridge patches.

greg.* hooks registry (IL2CPP)

This page documents the canonical C# / MelonLoader hook surface for Data Center IL2CPP interop: stable string ids, JSON registry, generated Harmony patches, and how they coexist with the existing Rust FFI bridge.

Canonical hook ids

Runtime identifiers follow:

greg.<DOMAIN>.<Action>

• greg — fixed prefix (never FMF, FFM, or product-specific spellings in new APIs).
• <DOMAIN> — uppercase segment from GregDomain (PLAYER, EMPLOYEE, NETWORK, UI, SYSTEM, …). Same logical areas as the framework domain model; see GregHookName in gregFramework sources.
• <Action> — PascalCase verb or noun phrase (MoneyChanged, Hired, ComponentInitialized, …).

Always build ids with GregHookName.Create(GregDomain.*, "Action") in mods — do not concatenate raw strings.

Registry file: greg_hooks.json

Location	Role
Repo root greg_hooks.json	Source of truth checked into gregFramework; documents every emitted hook (name, patchTarget, strategy, payloadSchema, optional legacy).
Next to FrikaModdingFramework.dll (build output)	Copy via FrikaMF.csproj (gregCore/framework/gregFramework/greg_hooks.json) so GregCompatBridge can resolve legacy ids at runtime.

The file is generated; edit the generator or whitelist (see below), then re-run the script — do not hand-edit hundreds of entries unless you are fixing metadata only.

Code layout (gregFramework repo)

Path	Purpose
gregCore/Core/	GregDomain, GregHookName, GregEventDispatcher, GregCompatBridge, GregPayload
gregCore/Hooks/	GregPlayerHooks, GregEmployeeHooks, … — Harmony postfix patches compiled into the MelonLoader plugin
gregCore/scripts/Generate-GregHooksFromIl2CppDump.ps1	Regenerates greg_hooks.json and all Greg*Hooks.cs files

The main plugin project (gregCore/framework/FrikaMF.csproj) references ..\Core\**\*.cs and ..\Hooks\**\*.cs. Harmony discovers any type in that assembly marked with [HarmonyPatch] (see Core.ApplyHarmonyPatchesWithDiagnostics).

Regeneration pipeline

1. Source of truth for patchable signatures — Il2CppInterop C# under gregReferences/il2cpp-unpack/Assembly-CSharp/Il2Cpp/*.cs (stand-in when a single-file MergedCode.md dump is not in the repo).

2. Run from repo root (PowerShell):

   pwsh -NoProfile -File gregCore/scripts/Generate-GregHooksFromIl2CppDump.ps1
   

3. Rebuild FrikaMF so hooks and copied JSON match.

Generator behaviour (summary)

• Emits postfix Harmony stubs with GregEventDispatcher.Emit and try/catch around each emit.
• Skips high-frequency Unity loops (Update, FixedUpdate, LateUpdate, OnUpdate), coroutine IEnumerator entrypoints, property accessors, and obvious IL2CPP noise (codegen, MethodInternalStatic, …).
• Skips ECS-heavy signatures unless Unity.Entities (and related) references are added to the project (Entity, EntityCommandBuffer, SystemState, BlobArray, …).
• Skips additional interop-only types where the project lacks references (e.g. some Unity.InputSystem, UI event types) — extend Test-SkipInteropSignature or add references when you need those patches.
• Overload policy: only the first overload per Type|MethodName per file is emitted (Harmony nameof ambiguity otherwise).
• Whitelist (gameHookClasses) — keeps the FrikaMF build green without pulling the entire game surface into scope; expand the list in the script when you add assembly references for more types.
• Harmony exclusion set — parses gregCore/framework/FrikaMF/HarmonyPatches.cs for HarmonyPatch(typeof(...), nameof(...)) / string method names so Rust bridge patches are not duplicated by generated Greg*Hooks (e.g. Player.UpdateCoin stays owned by the hand-written patch that already forwards to GregEventDispatcher).

Mod author entry points

• Greg hooks showcase — subscribe to greg.*, use GregPayload, optional cancelable flows where the bridge exposes them.
• FMF hook naming — older FMF.* / FFM.* string catalog and domain policy for documentation constants; runtime IL2CPP Harmony surface is greg.* as above.
• FMF hooks catalog — generated table from legacy HookNames / EventIds sources (distinct from greg_hooks.json).

Legacy hook ids

GregCompatBridge loads optional legacy → name mappings from greg_hooks.json next to the assembly. Populate legacy only when you intentionally support old spellings; keep new public API strictly on greg.*.

See also

• FFI, hooks & Lua
• Framework architecture
• Reference & technical hub