From 5e01054ac0d56faaa3c6af1fb00f39b41c683749 Mon Sep 17 00:00:00 2001
From: ChrisMiuchiz <chris000005@gmail.com>
Date: Tue, 23 Oct 2018 16:53:04 -0400
Subject: [PATCH] Add handler for chunk loading

Will be used for the building mod
---
 CallbackManager/main.cpp | 43 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

diff --git a/CallbackManager/main.cpp b/CallbackManager/main.cpp
index 78951e4..8d4881f 100644
--- a/CallbackManager/main.cpp
+++ b/CallbackManager/main.cpp
@@ -1,5 +1,6 @@
 #include "main.h"
 #include <vector>
+#define no_shenanigans __attribute__((noinline)) __declspec(dllexport)
 UINT_PTR base;
 
 //Chat Events
@@ -53,6 +54,44 @@ _declspec(naked) void DLL_EXPORT ASMHandleMessage(){
     asm("jmp eax");
 }
 
+//Chunk Loaded
+typedef void (__stdcall *ChunkLoadedCallback)(unsigned int zone_ptr);
+std::vector<ChunkLoadedCallback> chunk_loaded_callbacks;
+extern "C" void DLL_EXPORT RegisterChunkLoadedCallback(ChunkLoadedCallback func){
+    chunk_loaded_callbacks.push_back(func);
+}
+void __stdcall no_shenanigans HandleChunkLoaded(unsigned int zone_ptr){
+    for (ChunkLoadedCallback func : chunk_loaded_callbacks){
+        func(zone_ptr);
+    }
+}
+DWORD HandleChunkLoaded_ptr = (DWORD)&HandleChunkLoaded;
+
+unsigned int ASMHandleChunkLoaded_JMP_back;
+_declspec(naked) void DLL_EXPORT ASMHandleChunkLoaded(){
+    asm("push eax");
+    asm("push ebx");
+    asm("push ecx");
+    asm("push edx");
+    asm("push edi");
+    asm("push esi");
+
+    asm("push eax");
+    asm("call [_HandleChunkLoaded_ptr]");
+
+    asm("pop esi");
+    asm("pop edi");
+    asm("pop edx");
+    asm("pop ecx");
+    asm("pop ebx");
+    asm("pop eax");
+
+    asm("mov ecx, [ebx]"); //Original code
+    asm("add ecx, 0x800D44");
+
+    asm("jmp [_ASMHandleChunkLoaded_JMP_back]");
+}
+
 
 void WriteJMP(BYTE* location, BYTE* newFunction){
 	DWORD dwOldProtection;
@@ -69,6 +108,10 @@ extern "C" DLL_EXPORT BOOL APIENTRY DllMain(HINSTANCE hinstDLL, DWORD fdwReason,
     {
         case DLL_PROCESS_ATTACH:
             WriteJMP((BYTE*)(base + 0x7E61A), (BYTE*)&ASMHandleMessage);
+
+            ASMHandleChunkLoaded_JMP_back = base + 0x6ACDE;
+            WriteJMP((BYTE*)(base + 0x6ACD6), (BYTE*)&ASMHandleChunkLoaded);
+
             break;
     }
     return true;