/*
* Part of LaGUI demonstration programs
* Copyright (C) 2022-2023 Wu Yiming
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "la_5.h"

#include "lua.h"
#include "lauxlib.h"
#include "lualib.h"
#include "luajit.h"

#include <dlfcn.h>

STRUCTURE(MyData){
    int _pad;
    laSafeString* Code;
};

MyData Data={0};
lua_State *L;

char* default_code="local ffi = require(\"ffi\")\n\
\n\
ffi.cdef[[\n\
int printf(const char *fmt, ...);\n\
void ShowLaGUIMessagePanel(char* content);\n\
]]\n\
\n\
-- Simplest example:\n\
ffi.C.printf(\"Hello %s\", \"world!\\n\")\n\
\n\
-- To pass a string to a C function that takes a char*:\n\
local text=\"Hello from LuaJIT!\"\n\
local c_str = ffi.new(\"char[?]\", #text + 1)\n\
ffi.copy(c_str, text)\n\
ffi.C.ShowLaGUIMessagePanel(c_str);\n\
\n\
";

void ShowLaGUIMessagePanel(char* content){
    laEnableMessagePanel(0,0,"Message:",content,100,100,100,0);
}

void* myget_Data(void* unused, void* unused1){
    return &Data;
}

void MyPanel(laUiList *uil, laPropPack *This, laPropPack *DetachedProps, laColumn *UNUSED, int context){
    laColumn* c=laFirstColumn(uil);
    laShowItemFull(uil,c,0,"data.code",LA_WIDGET_STRING_MULTI,0,0,0)->Extra->HeightCoeff=-3;
    laShowItem(uil,c,0,"MY_call_luajit");
}

#define luaerr(hint)\
    sprintf(msg, hint "\n%s\n", lua_tostring(L, -1)); lua_pop(L, 1);\
    laEnableMessagePanel(a,0,"Error:",msg,e->x,e->y,100,e); return LA_FINISHED;

int INV_RunCode(laOperator* a, laEvent* e){
    char msg[2048]; int err=0;
    if(!Data.Code->Ptr) return LA_FINISHED;
    if(luaL_loadstring(L, Data.Code->Ptr)){ luaerr("luaL_loadstring() error:") };
    if(lua_pcall(L, 0, 0, 0)){ luaerr("lua_pcall() error:") };

    printf("Lua state globals:\n");
    lua_pushvalue(L,LUA_GLOBALSINDEX); //lua_pushglobaltable(L);       // Get global table
    lua_pushnil(L);               // put a nil key on stack
    while (lua_next(L,-2) != 0) { // key(-1) is replaced by the next key(-1) in table(-2)
        char* name = lua_tostring(L,-2);  // Get key(-2) name
        lua_pop(L,1);               // remove value(-1), now key on top at(-1)
        printf("%s\n",name);
    }
    lua_pop(L,1);

    // Getting binary exported functions this way directly in C
    // void *hndl = dlopen (NULL, RTLD_LAZY);
    // void (*fptr)(char*) = dlsym (hndl, "ShowLaGUIMessagePanel");
    // if(fptr){ fptr("well this is from dlsym"); }

    return LA_FINISHED;
}

int main(int argc, char *argv[]){
    laGetReady();

    transSetLanguage("zh-CN");

    strSafeSet(&Data.Code,default_code);
    L=luaL_newstate();
    luaL_openlibs(L);

    laRegisterUiTemplate("my_panel","My Panel", MyPanel,0,0,"Demonstration", 0,0,0);

    laCreateOperatorType("MY_call_luajit", "Call LuaJIT", "Load string into LuaJIT to call it",0,0,0,INV_RunCode,0,0,0);

    laPropContainer* root=laDefineRoot();
    laAddSubGroup(root,"data","Data","My Data", "my_data", 0,0,0,0,myget_Data,0,0,0,0,0,0,0);

    laPropContainer* my=laAddPropertyContainer("my_data", "MyData", "Struct MyData",0,0,0,0,0,LA_PROP_OTHER_ALLOC);
    laAddStringProperty(my, "code", "Code", "My code",0,0,0,0,1,offsetof(MyData,Code),0,0,0,0,0);

    laWindow* w = laDesignWindow(-1,-1,600,600);
    laLayout* l = laDesignLayout(w,"My Layout");
    laCreatePanel(l->FirstBlock,"my_panel");

    laStartWindow(w);
    laMainLoop();

    printf("Clearing Lua state.\n");
    lua_close(L);

    return 0;
}