From 3f8e1955cb04ffdb4182d0bc5d5833f37a2f2b44 Mon Sep 17 00:00:00 2001
From: Nick Gasson <nick@nickg.me.uk>
Date: Tue, 8 Jun 2010 21:44:25 +0100
Subject: [PATCH] Add Lua event hooks

---
 CMakeLists.txt     |  2 +-
 include/ILua.hpp   |  3 +++
 scripts/uidemo.lua |  3 ++-
 src/LuaWrap.cpp    | 47 +++++++++++++++++++++++++++++++++-------------
 src/UIDemo.cpp     |  2 +-
 5 files changed, 41 insertions(+), 16 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0151451..e34e676 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -54,7 +54,7 @@ add_executable (${PROJECT_NAME} WIN32 ${folder_source})
 
 target_link_libraries (${PROJECT_NAME} ${SDL_LIBRARY} ${SDLIMAGE_LIBRARY}
   ${OPENGL_LIBRARY} ${XERCES_LIBRARIES} ${Boost_LIBRARIES}
-  ${FREETYPE_LIBRARIES} ${GLEW_LIBRARY} ${LUA51_LIBRARIES})
+  ${FREETYPE_LIBRARIES} ${GLEW_LIBRARY} ${LUA_LIBRARY})
 
 # Profiling
 if (PROFILE)
diff --git a/include/ILua.hpp b/include/ILua.hpp
index c86756b..5648f12 100644
--- a/include/ILua.hpp
+++ b/include/ILua.hpp
@@ -26,6 +26,9 @@ struct ILua {
 
    virtual void eval(const string& code) = 0;
    virtual void loadFile(const string& file) = 0;
+
+   virtual void addHook(const string& tag) = 0;
+   virtual void runHook(const string& tag) = 0;
 };
 
 typedef shared_ptr<ILua> ILuaPtr;
diff --git a/scripts/uidemo.lua b/scripts/uidemo.lua
index 22924f2..61d60d0 100644
--- a/scripts/uidemo.lua
+++ b/scripts/uidemo.lua
@@ -5,9 +5,10 @@ function btn2Click(btn)
 end
 
 function layoutLoaded(layout)
+   debug("layout loaded")
    layout:get("/wnd/btn2"):connect(
       gui.Widget.SIG_CLICK,
       btn2Click)
 end
 
-addHook("layoutLoaded", layoutLoaded)
+hook("layoutLoaded", layoutLoaded)
diff --git a/src/LuaWrap.cpp b/src/LuaWrap.cpp
index e4836ec..34f79a0 100644
--- a/src/LuaWrap.cpp
+++ b/src/LuaWrap.cpp
@@ -52,38 +52,43 @@ public:
 
    void eval(const string& code);
    void loadFile(const string& file);
+   
+   void addHook(const string& tag);
+   void runHook(const string& tag);
 private:
-   void pcall();
+   void pcall(int nargs = 0, int nresults = 0);
    
-   lua_State* luaVM;
+   lua_State* L;
 };
 
 LuaWrap::LuaWrap()
 {
    log() << "Creating Lua VM";
    
-   if ((luaVM = lua_open()) == NULL) 
+   if ((L = lua_open()) == NULL) 
       throw runtime_error("Failed to initialise Lua");
 
-   lua_pushvalue(luaVM, LUA_GLOBALSINDEX);
-   luaL_register(luaVM, NULL, luaFuncs);
-   lua_pop(luaVM, 1);
+   lua_pushvalue(L, LUA_GLOBALSINDEX);
+   luaL_register(L, NULL, luaFuncs);
+   lua_pop(L, 1);
+
+   loadFile("scripts/init.lua");
 }
 
 LuaWrap::~LuaWrap()
 {
-   lua_close(luaVM);
+   lua_close(L);
 }
 
-void LuaWrap::pcall()
+void LuaWrap::pcall(int nargs, int nresults)
 {
-   int result = lua_pcall(luaVM, 0, 0, 0);
+   int result = lua_pcall(L, nargs, nresults, 0);
    
    switch (result) {
    case LUA_ERRRUN:
    case LUA_ERRERR:
-      error() << lua_tolstring(luaVM, -1, NULL);
-      lua_pop(luaVM, 1);
+      error() << lua_tolstring(L, -1, NULL);
+      lua_pop(L, 1);
       break;
    case LUA_ERRMEM:
       error() << "Lua out of memory!";
@@ -93,7 +98,7 @@ void LuaWrap::pcall()
 
 void LuaWrap::eval(const string& code)
 {
-   int result = luaL_loadstring(luaVM, code.c_str());
+   int result = luaL_loadstring(L, code.c_str());
    
    switch (result) {
    case LUA_ERRSYNTAX:
@@ -111,7 +116,7 @@ void LuaWrap::loadFile(const string& file)
 {
    log() << "Loading Lua script " << file;
    
-   int result = luaL_loadfile(luaVM, file.c_str());
+   int result = luaL_loadfile(L, file.c_str());
    
    switch (result) {
    case LUA_ERRSYNTAX:
@@ -128,6 +133,22 @@ void LuaWrap::loadFile(const string& file)
    pcall();
 }
 
+void LuaWrap::addHook(const string& tag)
+{
+   lua_getglobal(L, "_hooks");
+   lua_getglobal(L, "_default_hook");
+
+   lua_setfield(L, -2, tag.c_str());
+}
+
+void LuaWrap::runHook(const string& tag)
+{
+   lua_getglobal(L, "_hooks");
+   lua_getfield(L, -1, tag.c_str());
+
+   pcall(0, 0);
+}
+
 ILuaPtr getLua()
 {
    static ILuaPtr lua;
diff --git a/src/UIDemo.cpp b/src/UIDemo.cpp
index a2040b9..232e023 100644
--- a/src/UIDemo.cpp
+++ b/src/UIDemo.cpp
@@ -56,7 +56,7 @@ UIDemo::UIDemo()
 	bind(&UIDemo::btn1Click, this, _1));
 
     ILuaPtr lua = getLua();
-    lua->makeHook("layoutLoaded");    
+    lua->addHook("layoutLoaded");    
     lua->loadFile("scripts/uidemo.lua");
     lua->runHook("layoutLoaded");
 }
-- 
2.39.2