source: UI/ui_lua.cpp @ 69

/*
 * Filename      : UI/ui_lua.cpp
 * Author(s)     : Matt Zweig (thezweig@gmail.com)
 * Date Created  : Thursday, October 29, 2009
 * Last Modified : Thursday, October 29, 2009
 * Purpose       : Lua bridge for UI objects
 * Notes         :
 */
  
#include "UI/ui.h"
#include "ui_lua.h"
#include "ui_label.h"
#include "ui_window.h"
#include "ui_button.h"

void UI_Lua::RegisterUI(lua_State *luaVM){
        static const luaL_Reg uiFunctions[] = {
                // Creation
                {"newWindow", &UI_Lua::newWindow},
                {"newButton", &UI_Lua::newButton},
                {"newLabel", &UI_Lua::newLabel},
                {"close", &UI_Lua::close},
                {"add", &UI_Lua::add},
                {NULL, NULL}
        };
        luaL_newmetatable(luaVM, "EpiarLua.UI");
        luaL_openlib(luaVM, "EpiarLua.UI", uiFunctions,0);  
}

int UI_Lua::newWindow(lua_State *luaVM){
        int arg;
        int n = lua_gettop(luaVM);  // Number of arguments
        if (n < 6)
                return luaL_error(luaVM, "Got %d arguments expected 6 (class, x, y, w, h, caption, [ Widgets ... ])", n);

        double x = luaL_checknumber (luaVM, 2);
        double y = luaL_checknumber (luaVM, 3);
        double w = luaL_checknumber (luaVM, 4);
        double h = luaL_checknumber (luaVM, 5);
        string caption = luaL_checkstring (luaVM, 6);

        // Allocate memory for a pointer to object
        Window **win = (Window**)lua_newuserdata(luaVM, sizeof(Window*));
        *win = new Window(x,y,w,h,caption);
        //(*win)->AddChild( new Button( 152, 262, 96, 25, "OK" ) );

        // Add this Window
        UI::Add(*win);

        // Collect 'extra' widgets and Add them as children
        for(arg=7; arg<=n;arg++){
                Widget** widget= (Widget**)lua_touserdata(luaVM,arg);
                (*win)->AddChild(*widget);
        }
        
        return 1;
}

int UI_Lua::close(lua_State *luaVM){
        int n = lua_gettop(luaVM);  // Number of arguments

        if (n == 1) {
                UI::Close();
        }
        else {
                luaL_error(luaVM, "Got %d arguments expected 1 (class)", n); 
        }
        return 0;
}

int UI_Lua::newButton(lua_State *luaVM){
        int n = lua_gettop(luaVM);  // Number of arguments
        if (n != 6)
                return luaL_error(luaVM, "Got %d arguments expected 5 (class, x, y, w, h, caption)", n);

        double x = luaL_checknumber (luaVM, 2);
        double y = luaL_checknumber (luaVM, 3);
        double w = luaL_checknumber (luaVM, 4);
        double h = luaL_checknumber (luaVM, 5);
        string caption = luaL_checkstring (luaVM, 6);

        // Allocate memory for a pointer to object
        Button **button= (Button**)lua_newuserdata(luaVM, sizeof(Button*));
        *button = new Button(x,y,w,h,caption);

        // Note: We're not putting this button anywhere!
        //       Lua will have to do that for us.
        //       This may be a bad idea (memory leaks from bad lua scripts)

        return 1;
}

int UI_Lua::newLabel(lua_State *luaVM){
        int n = lua_gettop(luaVM);  // Number of arguments
        if (n != 4)
                return luaL_error(luaVM, "Got %d arguments expected 4 (class, x, y, caption)", n);

        double x = luaL_checknumber (luaVM, 2);
        double y = luaL_checknumber (luaVM, 3);
        string caption = luaL_checkstring (luaVM, 4);

        // Allocate memory for a pointer to object
        Label **label= (Label**)lua_newuserdata(luaVM, sizeof(Label*));
        *label = new Label(x,y,caption);

        // Note: We're not putting this Label anywhere!
        //       Lua will have to do that for us.
        //       This may be a bad idea (memory leaks from bad lua scripts)

        return 1;
}

int UI_Lua::add(lua_State *luaVM){
        int n = lua_gettop(luaVM);  // Number of arguments
        if (n == 2){
                Widget** ptrOuter = (Widget**)lua_touserdata(luaVM,1);
                Widget** ptrInner = (Widget**)lua_touserdata(luaVM,2);
                (*ptrOuter)->AddChild(*ptrInner);
        } else {
                luaL_error(luaVM, "Got %d arguments expected 2 (self, widget)", n); 
        }
        return 0;
}