source: trunk/src/lua/lua_state.cc @ 538

// Copyright (C) 2012-2015 ChaosForge Ltd
// http://chaosforge.org/
//
// This file is part of Nova libraries. 
// For conditions of distribution and use, see copying.txt file in root folder.

#include "nv/lua/lua_state.hh"

#include "nv/lua/lua_raw.hh"
#include "nv/lua/lua_nova.hh"
#include "nv/lua/lua_types.hh"
#include "nv/core/logging.hh"
#include "nv/stl/string.hh"

using namespace nv;

// stack_guard

#define NV_LUA_ABORT( func, ... ) \
        NV_LOG_CRITICAL( "lua::" func " : ", __VA_ARGS__ ) \
        NV_ABORT( "lua::" func " : critical error!" )


lua::stack_guard::stack_guard( lua::state* aL )
        : L(aL), m_level( lua_gettop(aL->m_state) )
{

}

lua::stack_guard::stack_guard( lua::state& aL )
        : L(&aL), m_level( lua_gettop(aL.m_state) )
{

}

lua::stack_guard::~stack_guard()
{
        lua_settop( L->m_state, m_level );
}

// stack_assert
nv::lua::stack_assert::stack_assert( lua::state* aL, int expected )
        : L(aL->get_raw()), m_expected( lua_gettop(aL->get_raw() ) + expected )
{

}

nv::lua::stack_assert::stack_assert( lua::state& aL, int expected )
        : L(aL.get_raw()), m_expected( lua_gettop(aL.get_raw() ) + expected )
{

}

nv::lua::stack_assert::stack_assert( lua_State* aL, int expected )
        : L(aL), m_expected( lua_gettop(aL) + expected )
{

}

lua::stack_assert::~stack_assert()
{
        NV_ASSERT( lua_gettop(L) == m_expected, "Lua stack corruption detected!" );
}


// state_wrapper

void nv::lua::state_wrapper::push_global_table()
{
        nlua_pushglobaltable( m_state );
}

void nv::lua::state_wrapper::pop_global_table()
{
        lua_replace( m_state, -2 );
}

void lua::state_wrapper::call_get()
{
        lua_gettable( m_state, -2 );
}

void lua::state_wrapper::call_get_raw()
{
        lua_rawget( m_state, -2 );
}

void lua::state_wrapper::register_native_function( lfunction f, string_view name )
{
        if ( m_global ) push_global_table();
        lua_pushcfunction( m_state, f );
        lua_setfield( m_state, -2, name.data() );
        if ( m_global ) pop_global_table();
}

lua::state_wrapper::~state_wrapper()
{
        if (m_owner)
        {
                lua_close( m_state );
        }
}

bool nv::lua::state_wrapper::is_defined( const path& p, bool global )
{
        if ( !p.resolve( m_state, global ) )
        {
                return false;
        }
        bool result = !lua_isnil( m_state, -1 );
        lua_pop( m_state, 1 );
        return result;
}

bool nv::lua::state_wrapper::push_function( const path& p, bool global )
{
        if ( !p.resolve( m_state, global ) )
        {
                NV_LOG_ERROR( "Lua error : not a valid path - ", p.to_string() );
                return false;
        }

        if ( !lua_isfunction( m_state, -1 ) ) 
        {
                lua_pop( m_state, 1 );
                NV_LOG_ERROR( "Lua error : not a valid function - ", p.to_string() );
                return false;
        }
        return true;
}

int nv::lua::state_wrapper::call_function( int nargs, int nresults )
{
        int status = lua_pcall( m_state, nargs, nresults, 0 );
        if ( status != 0 )
        {
                NV_LOG_ERROR( "Lua error : ", nlua_tostringview( m_state, -1 ) );
                lua_pop( m_state, 1 );
        }
        return status;
}

// table_guard

lua::table_guard::table_guard( lua::state* lstate, const path& p, bool global )
        : state_wrapper( lstate->get_raw(), lstate->m_lua_types, false ), m_parent( lstate ), m_level(0)
{
        m_global = false;
        m_level  = lua_gettop( m_state );
        if ( !p.resolve( m_state, global ) || lua_type(m_state, -1) != LUA_TTABLE )
        {
                NV_LOG_ERROR( "Could not resolve table!" );
                // TODO : error handling
        }
}

lua::table_guard::table_guard( const table_guard& parent, const path& p )
        : state_wrapper( parent.m_state, parent.m_lua_types, false ), m_parent( parent.m_parent ), m_level(0)
{
        m_global = false;
        m_level  = lua_gettop( m_state );
        if ( !p.resolve( m_state, false ) || lua_type(m_state, -1) != LUA_TTABLE )
        {
                NV_LOG_ERROR( "Could not resolve table!" );
                // TODO : error handling
        }
}

lua::table_guard::~table_guard()
{
        lua_settop( m_state, m_level );
}

nv::uint32 lua::table_guard::get_size()
{
        return nlua_rawlen( m_state, -1 );
}

bool lua::table_guard::has_field( string_view element )
{
        lua_getfield( m_state, -1, element.data() );
        bool result = !( lua_isnil( m_state, -1 ) );
        lua_pop( m_state, 1 );
        return result;
}

shash64 nv::lua::table_guard::get_string_hash_64( string_view element, uint64 defval /*= 0 */ )
{
        lua_getfield( m_state, -1, element.data() );
        size_t l = 0;
        const char* str = nullptr;
        uint64 result = defval;
        if ( lua_type( m_state, -1 ) == LUA_TSTRING )
        {
                str = lua_tolstring( m_state, -1, &l );
                result = hash_string< uint64 >( str, static_cast< uint32 >( l ) );
                //NV_LOG_DEBUG( str );
        }
        lua_pop( m_state, 1 );
        return shash64( result );
}

nv::shash64 nv::lua::table_guard::get_string( string_view element, string_table* table, uint64 defval /*= 0 */ )
{
        lua_getfield( m_state, -1, element.data() );
        size_t l = 0;
        const char* str = nullptr;
        shash64 result = shash64( defval );
        if ( lua_type( m_state, -1 ) == LUA_TSTRING )
        {
                str = lua_tolstring( m_state, -1, &l );
                string_view sv( str, static_cast< uint32 >( l ) );
                result = table ? table->insert( sv ) : shash64( sv );
        }
        lua_pop( m_state, 1 );
        return result;
}

shash64 nv::lua::table_guard::get_string_hash_64( int i, uint64 defval /*= 0 */ )
{
        lua_rawgeti( m_state, -1, i );
        size_t l = 0;
        const char* str = nullptr;
        uint64 result = defval;
        if ( lua_type( m_state, -1 ) == LUA_TSTRING )
        {
                str = lua_tolstring( m_state, -1, &l );
                result = hash_string< uint64 >( str, static_cast< uint32 >( l ) );
                //NV_LOG_DEBUG( str );
        }
        lua_pop( m_state, 1 );
        return shash64( result );
}

nv::string128 nv::lua::table_guard::get_string128( int i, string_view defval /*= string_view() */ )
{
        lua_rawgeti( m_state, -1, i );
        size_t l = 0;
        const char* str = nullptr;
        if ( lua_type( m_state, -1 ) == LUA_TSTRING )
        {
                str = lua_tolstring( m_state, -1, &l );
        }
        else
        {
                l = defval.size();
                str = defval.data();
        }
        string128 result( str, static_cast< uint32 >( l ) );
        lua_pop( m_state, 1 );
        return result;
}

const_string nv::lua::table_guard::get_string( int i, string_view defval /*= string_view() */ )
{
        lua_rawgeti( m_state, -1, i );
        size_t l = 0;
        const char* str = nullptr;
        if ( lua_type( m_state, -1 ) == LUA_TSTRING )
        {
                str = lua_tolstring( m_state, -1, &l );
        }
        else
        {
                l = defval.size();
                str = defval.data();
        }
        const_string result( str, static_cast< uint32 >( l ) );
        lua_pop( m_state, 1 );
        return result;
}

shash64 nv::lua::table_guard::get_string( int i, string_table* table, uint64 defval /*= 0 */ )
{
        lua_rawgeti( m_state, -1, i );
        size_t l = 0;
        const char* str = nullptr;
        shash64 result = shash64( defval );
        if ( lua_type( m_state, -1 ) == LUA_TSTRING )
        {
                str = lua_tolstring( m_state, -1, &l );
                string_view sv( str, static_cast< uint32 >( l ) );
                result = table ? table->insert( sv ) : shash64( sv );
        }
        lua_pop( m_state, 1 );
        return result;
}

const_string lua::table_guard::get_string( string_view element, string_view defval /*= string_view() */ )
{
        lua_getfield( m_state, -1, element.data() );
        size_t l = 0;
        const char* str = nullptr;
        if ( lua_type( m_state, -1 ) == LUA_TSTRING )
        {
                str = lua_tolstring( m_state, -1, &l );
        }
        else
        {
                l = defval.size();
                str = defval.data();
        }
        const_string result( str, static_cast< uint32 >( l ) );
        lua_pop( m_state, 1 );
        return result;
}

string128 lua::table_guard::get_string128( string_view element, string_view defval )
{
        lua_getfield( m_state, -1, element.data() );
        size_t l = 0;
        const char* str = nullptr;
        if ( lua_type( m_state, -1 ) == LUA_TSTRING )
        {
                str = lua_tolstring( m_state, -1, &l );
        }
        else
        {
                l = defval.size();
                str = defval.data();
        }
        string128 result( str, static_cast< uint32 >( l ) );
        lua_pop( m_state, 1 );
        return result;
}

nv::string64 nv::lua::table_guard::get_string64( string_view element, string_view defval /*= string_view() */ )
{
        lua_getfield( m_state, -1, element.data() );
        size_t l = 0;
        const char* str = nullptr;
        if ( lua_type( m_state, -1 ) == LUA_TSTRING )
        {
                str = lua_tolstring( m_state, -1, &l );
        }
        else
        {
                l = defval.size();
                str = defval.data();
        }
        string64 result( str, static_cast< uint32 >( l ) );
        lua_pop( m_state, 1 );
        return result;
}


nv::string32 nv::lua::table_guard::get_string32( string_view element, string_view defval /*= string_view() */ )
{
        lua_getfield( m_state, -1, element.data() );
        size_t l = 0;
        const char* str = nullptr;
        if ( lua_type( m_state, -1 ) == LUA_TSTRING )
        {
                str = lua_tolstring( m_state, -1, &l );
        }
        else
        {
                l = defval.size();
                str = defval.data();
        }
        string32 result( str, static_cast< uint32 >( l ) );
        lua_pop( m_state, 1 );
        return result;
}

char lua::table_guard::get_char( string_view element, char defval /*= "" */ )
{
        lua_getfield( m_state, -1, element.data() );
        char result = ( lua_type( m_state, -1 ) == LUA_TSTRING && nlua_rawlen( m_state, -1 ) > 0 ) ? lua_tostring( m_state, -1 )[0] : defval;
        lua_pop( m_state, 1 );
        return result;
}

int lua::table_guard::get_integer( string_view element, int defval /*= "" */ )
{
        lua_getfield( m_state, -1, element.data() );
        lua_Integer result = lua_type( m_state, -1 ) == LUA_TNUMBER ? lua_tointeger( m_state, -1 ) : defval;
        lua_pop( m_state, 1 );
        return static_cast< int >( result );
}

unsigned lua::table_guard::get_unsigned( string_view element, unsigned defval /*= "" */ )
{
        lua_getfield( m_state, -1, element.data() );
        unsigned result = lua_type( m_state, -1 ) == LUA_TNUMBER ? nlua_tounsigned( m_state, -1 ) : defval;
        lua_pop( m_state, 1 );
        return result;
}

double lua::table_guard::get_double( string_view element, double defval /*= "" */ )
{
        lua_getfield( m_state, -1, element.data() );
        double result = lua_type( m_state, -1 ) == LUA_TNUMBER ? lua_tonumber( m_state, -1 ) : defval;
        lua_pop( m_state, 1 );
        return result;
}

char nv::lua::table_guard::get_char( int i, char defval /*= ' ' */ )
{
        lua_rawgeti( m_state, -1, i );
        char result = ( lua_type( m_state, -1 ) == LUA_TSTRING && nlua_rawlen( m_state, -1 ) > 0 ) ? lua_tostring( m_state, -1 )[0] : defval;
        lua_pop( m_state, 1 );
        return result;
}

int nv::lua::table_guard::get_integer( int i, int defval /*= 0 */ )
{
        lua_rawgeti( m_state, -1, i );
        lua_Integer result = lua_type( m_state, -1 ) == LUA_TNUMBER ? lua_tointeger( m_state, -1 ) : defval;
        lua_pop( m_state, 1 );
        return static_cast<int>( result );
}

unsigned nv::lua::table_guard::get_unsigned( int i, unsigned defval /*= 0 */ )
{
        lua_rawgeti( m_state, -1, i );
        unsigned result = lua_type( m_state, -1 ) == LUA_TNUMBER ? nlua_tounsigned( m_state, -1 ) : defval;
        lua_pop( m_state, 1 );
        return result;
}

double nv::lua::table_guard::get_double( int i, double defval /*= 0.0 */ )
{
        lua_rawgeti( m_state, -1, i );
        double result = lua_type( m_state, -1 ) == LUA_TNUMBER ? lua_tonumber( m_state, -1 ) : defval;
        lua_pop( m_state, 1 );
        return result;
}

float nv::lua::table_guard::get_float( int i, float defval /*= 0.0 */ )
{
        lua_rawgeti( m_state, -1, i );
        float result = lua_type( m_state, -1 ) == LUA_TNUMBER ? static_cast<float>( lua_tonumber( m_state, -1 ) ) : defval;
        lua_pop( m_state, 1 );
        return result;
}

bool nv::lua::table_guard::get_boolean( int i, bool defval /*= false */ )
{
        lua_rawgeti( m_state, -1, i );
        bool result = lua_type( m_state, -1 ) == LUA_TBOOLEAN ? lua_toboolean( m_state, -1 ) != 0 : defval;
        lua_pop( m_state, 1 );
        return result;
}

float nv::lua::table_guard::get_float( string_view element, float defval /*= 0.0 */ )
{
        lua_getfield( m_state, -1, element.data() );
        float result = lua_type( m_state, -1 ) == LUA_TNUMBER ? static_cast<float>( lua_tonumber( m_state, -1 ) ) : defval;
        lua_pop( m_state, 1 );
        return result;
}

bool lua::table_guard::get_boolean( string_view element, bool defval /*= "" */ )
{
        lua_getfield( m_state, -1, element.data() );
        bool result = lua_type( m_state, -1 ) == LUA_TBOOLEAN ? lua_toboolean( m_state, -1 ) != 0 : defval;
        lua_pop( m_state, 1 );
        return result;
}

bool nv::lua::table_guard::is_table( string_view element )
{
        lua_getfield( m_state, -1, element.data() );
        bool result = lua_type( m_state, -1 ) == LUA_TTABLE;
        lua_pop( m_state, 1 );
        return result;
}

bool nv::lua::table_guard::is_table( int i )
{
        lua_rawgeti( m_state, -1, i );
        bool result = lua_type( m_state, -1 ) == LUA_TTABLE;
        lua_pop( m_state, 1 );
        return result;
}

bool nv::lua::table_guard::is_number( int i )
{
        lua_rawgeti( m_state, -1, i );
        bool result = lua_type( m_state, -1 ) == LUA_TNUMBER;
        lua_pop( m_state, 1 );
        return result;
}

bool nv::lua::table_guard::is_boolean( int i )
{
        lua_rawgeti( m_state, -1, i );
        bool result = lua_type( m_state, -1 ) == LUA_TBOOLEAN;
        lua_pop( m_state, 1 );
        return result;
}

bool nv::lua::table_guard::is_string( int i )
{
        lua_rawgeti( m_state, -1, i );
        bool result = lua_type( m_state, -1 ) == LUA_TSTRING;
        lua_pop( m_state, 1 );
        return result;
}

bool nv::lua::table_guard::is_number( string_view element )
{
        lua_getfield( m_state, -1, element.data() );
        bool result = lua_type( m_state, -1 ) == LUA_TNUMBER;
        lua_pop( m_state, 1 );
        return result;
}

bool nv::lua::table_guard::is_boolean( string_view element )
{
        lua_getfield( m_state, -1, element.data() );
        bool result = lua_type( m_state, -1 ) == LUA_TBOOLEAN;
        lua_pop( m_state, 1 );
        return result;
}

bool nv::lua::table_guard::is_string( string_view element )
{
        lua_getfield( m_state, -1, element.data() );
        bool result = lua_type( m_state, -1 ) == LUA_TSTRING;
        lua_pop( m_state, 1 );
        return result;
}

bool nv::lua::table_guard::read( const string_view& element, const type_entry* entry, void* object )
{
        NV_ASSERT_ALWAYS( m_lua_types->get_type_database() == entry->type_db, "Type database mismatch between Lua and entry!" );
        lua_getfield( m_state, -1, element.data() );
        if ( lua_type( m_state, -1 ) != LUA_TTABLE )
        {
                lua_pop( m_state, 1 );
                return false;
        }
        if ( !nv::lua::read_rtti_type( m_parent, entry, object, -1 ) )
        {
                lua_pop( m_state, 1 );
                return false;
        }
        lua_pop( m_state, 1 );
        return true;
}

// state

lua::state::state( lua_State* state, type_database* types )
        : state_wrapper( state, new type_data( types ), false )
{

}

lua::state::state( bool load_libs /*= false*/, type_database* types )
        : state_wrapper( nullptr, new type_data( types ), true )
{
        load_lua_library();
        m_owner = true;
        m_state = luaL_newstate( );

        lua_pushcfunction(m_state, luaopen_base);
        lua_pushliteral(m_state, "");
        lua_call(m_state, 1, 0);

        {
                // Preregister 8 references for Handle registry
                lua_newtable(m_state);
                NV_ASSERT( luaL_ref( m_state, LUA_REGISTRYINDEX ) == 1, "First reference not 1!" );
                for ( uint32 i = 1; i < 8; ++i )
                {
                        lua_newtable(m_state);
                        luaL_ref( m_state, LUA_REGISTRYINDEX );
                }
        }

        if ( load_libs )
        {
                stack_guard guard( this );
                static const luaL_Reg lualibs[] =
                {
                        { "string", luaopen_string },
                        { "table",  luaopen_table },
                        { "math",   luaopen_math },
                        { NULL, NULL}
                };
                const luaL_Reg *lib = lualibs;
                for(; lib->func != NULL; lib++)
                {
                        lua_pushcfunction( m_state, lib->func );
                        lua_call(m_state, 0, 1);
                        lua_setglobal( m_state, lib->name );
                }
                register_nova( this );
        }

        NV_LOG_TRACE( "Lua state created" );
}

int lua::state::load_string( string_view code, string_view name )
{
        NV_LOG_TRACE( "Loading Lua string '", name, "'");
        return luaL_loadbuffer( m_state, code.data(), code.length(), name.data() );
}

int lua::state::load_file( string_view filename )
{
        NV_LOG_NOTICE( "Loading Lua file '", filename, "'");
        return luaL_loadfile( m_state, filename.data() );
}

bool lua::state::do_string( string_view code, string_view name, int rvalues )
{
        lua::stack_guard( this );
        int result = load_string(code,name);
        if (result)
        {
                NV_LOG_WARNING( "Failed to load string ", name, ": ", nlua_tostringview(m_state, -1));
                return false;
        }
        return do_current( name, rvalues ) == 0;
}

bool lua::state::do_file( string_view filename )
{
        lua::stack_guard( this );
        int result = load_file(filename);
        if (result) 
        {
                NV_LOG_WARNING( "Failed to open file ", filename, ": ", nlua_tostringview( m_state, -1 ) );
                return false;
        }
        return do_current( filename ) == 0;
}

int lua::state::do_current( string_view name, int rvalues )
{
        int result = lua_pcall(m_state, 0, rvalues, 0);
        if (result) 
        {
                NV_LOG_WARNING( "Failed to run script ", name, ": ", nlua_tostringview( m_state, -1 ) );
                lua_pop( m_state, 1 );
        }
        return result;
}

int lua::state::get_stack_size()
{
        return lua_gettop( m_state );
}

void lua::state::log_stack()
{
        int top = lua_gettop(m_state);
        NV_LOG_DEBUG( "Stack dump (", top, ")");
        for ( int i = 0; i < top; ++i )
        {
                NV_LOG_DEBUG( "#", i+1, " - ", lua_typename(m_state, lua_type(m_state, i+1) ), " = ", nlua_typecontent(m_state, i+1) );
        }
}

lua_State* lua::state::get_raw()
{
        return m_state;
}

lua::ref lua::state::register_object( void* o, string_view lua_name )
{
        if ( o == nullptr ) return lua::ref( lua::ref::none );
        stack_guard guard( this );
        lua_getglobal( m_state, lua_name.data() );
        if ( lua_isnil( m_state, -1 ) )
        {
                NV_LUA_ABORT( "state::register_object", lua_name, " type not registered!" );
        }
        deep_pointer_copy( -1, o );
        return lua::ref( luaL_ref( m_state, LUA_REGISTRYINDEX ) );
}

lua::ref lua::state::register_proto( string_view id, string_view storage )
{
        stack_guard guard( this );
        lua_getglobal( m_state, storage.data() );
        if ( lua_isnil( m_state, -1 ) )
        {
                NV_LUA_ABORT( "state::register_proto", "\"", storage, "\" storage not registered!" );
        }
        lua_getfield( m_state, -1, id.data() );
        if ( lua_isnil( m_state, -1 ) )
        {
                NV_LUA_ABORT( "state::register_proto", "\"", id, "\" not found in \"", storage, "\"!" );
        }
        return lua::ref( luaL_ref( m_state, LUA_REGISTRYINDEX ) );
}

void lua::state::register_native_object_method( string_view lua_name, string_view name, lfunction f )
{
        stack_guard guard( this );
        lua_getglobal( m_state, lua_name.data() );
        if ( lua_isnil( m_state, -1 ) )
        {
                NV_LUA_ABORT( "state::register_native_object_method", "\"", lua_name, "\" type not registered!" );
        }
        lua_pushcfunction( m_state, f );
        lua_setfield( m_state, -2, name.data() );
}

void lua::state::unregister_object( ref object_index )
{
        if ( !object_index.is_valid() ) return;
        stack_guard guard( this );
        lua_rawgeti( m_state, LUA_REGISTRYINDEX, object_index.get() );
        lua_pushliteral( m_state, "__ptr" );
        lua_pushboolean( m_state, false );
        lua_rawset( m_state, -3 );
        lua_pop( m_state, 1 );
        luaL_unref( m_state, LUA_REGISTRYINDEX, object_index.get() );
}


void lua::state::deep_pointer_copy( int index, void* obj )
{
        index = nlua_absindex( m_state, index );
        lua_newtable( m_state );
        lua_pushnil( m_state );
        bool has_functions = false;
        bool has_metatable = false;

        while ( lua_next( m_state, index ) != 0 )
        {
                if ( lua_isfunction( m_state, -1 ) ) 
                        has_functions = true;
                else if ( lua_istable( m_state, -1 ) )
                {
                        deep_pointer_copy( -1, obj );
                        lua_insert( m_state, -2 );
                        lua_pop( m_state, 1 );
                }
                lua_pushvalue( m_state, -2 );
                lua_insert( m_state, -2 );
                lua_settable( m_state, -4 );
        }

        if ( lua_getmetatable( m_state, -2 ) )
        {
                lua_setmetatable( m_state, -2 );
                has_metatable = true;
        }

        if ( has_functions || has_metatable )
        {
                lua_pushliteral( m_state, "__ptr" );
                lua_pushlightuserdata( m_state, obj );
                lua_rawset( m_state, -3 );
        }
}

void nv::lua::state::store_metadata( ref object_index, string_view metaname, void* pointer )
{
        if ( !object_index.is_valid() ) return;
        lua_rawgeti( m_state, LUA_REGISTRYINDEX, object_index.get() );
        nlua_pushstringview( m_state, metaname );
        lua_pushlightuserdata( m_state, pointer );
        lua_rawset( m_state, -3 );
        lua_pop( m_state, 1 );
}

void nv::lua::state::register_enum( string_view name, int value )
{
        lua_pushinteger( m_state, value );
        lua_setglobal( m_state, name.data() );
}

void nv::lua::state::register_enum( const type_entry* type )
{
        NV_ASSERT_ALWAYS( type, "type not found!" );
        NV_ASSERT_ALWAYS( !type->enum_list.empty(), "type not enum!" );
        type_database* db = type->type_db;
        for ( auto e : type->enum_list )
        {
                lua_pushinteger( m_state, e.value );
                lua_setglobal( m_state, db->resolve_name( e.name ).data() );
        }
}

void nv::lua::state::register_rtti_type( thash64 tid, lua_rtti_push_function p, lua_rtti_read_function r )
{
        m_lua_types->insert( tid, p, r );
}

nv::lua::ref nv::lua::state::register_handle_component_impl( string_view id, bool empty )
{
        int args = empty ? 1 : 2;
        NV_LUA_STACK_ASSERT( m_state, -args );

        if ( lua_isnil( m_state, -1 ) || (!empty && lua_isnil( m_state, -2 )) )
        {
                lua_pop( m_state, args );
                return ref();
        }
        if (empty)
                lua_createtable( m_state, 0, 0 );
        else
                nlua_deepcopy( m_state, -2 );
        nlua_pushstringview( m_state, id );
        lua_pushvalue( m_state, -2 );
        lua_rawset( m_state, -4 );
        lua_replace( m_state, -2 );
        ref result = lua::ref( luaL_ref( m_state, LUA_REGISTRYINDEX ) );
        if (!empty) lua_pop( m_state, 1 );
        return result;
}

void nv::lua::state::unregister_handle_component_impl( string_view id )
{
        NV_LUA_STACK_ASSERT( m_state, -1 );

        if ( lua_isnil( m_state, -1 ) )
        {
                lua_pop( m_state, 1 );
                return;
        }
        nlua_pushstringview( m_state, id );
        lua_pushnil( m_state );
        lua_rawset( m_state, -3 );
        lua_pop( m_state, 1 );
}

void nv::lua::state::register_singleton( string_view name, void* o )
{
        if ( o == nullptr ) return;
        stack_guard guard( this );
        lua_getglobal( m_state, name.data() );
        if ( lua_isnil( m_state, -1 ) )
        {
                NV_LUA_ABORT( "state::register_singleton", "\"", name, "\" type not registered!" );
        }
        deep_pointer_copy( -1, o );
        lua_setglobal( m_state, name.data() );
}

nv::lua::state::~state()
{
        delete m_lua_types;
        m_lua_types = nullptr;
}

template < typename T >
void nlua_rtti_signed_push( nv::lua::state* state, const type_entry*, void* object )
{
        T* value = reinterpret_cast<T*>( object );
        lua_pushinteger( state->get_raw(), lua_Integer( *value ) );
}

template < typename T >
void nlua_rtti_unsigned_push( nv::lua::state* state, const type_entry*, void* object )
{
        T* value = reinterpret_cast<T*>( object );
        lua_pushinteger( state->get_raw(), lua_Unsigned( *value ) );
}

template < typename T >
void nlua_rtti_floating_push( nv::lua::state* state, const type_entry*, void* object )
{
        T* value = reinterpret_cast< T* >( object );
        lua_pushnumber( state->get_raw(), lua_Number( *value ) );
}

static void nlua_rtti_boolean_push( nv::lua::state* state, const type_entry*, void* object )
{
        bool* value = reinterpret_cast<bool*>( object );
        lua_pushboolean( state->get_raw(), *value );
}

template < typename T >
bool nlua_rtti_signed_read( nv::lua::state* state, const type_entry*, void* object, int index )
{
        T* value = reinterpret_cast<T*>( object );
        if ( lua_type( state->get_raw(), index ) == LUA_TNUMBER )
        {
                *value = T( lua_tointeger( state->get_raw(), index ) );
                return true;
        }
        return false;
}

template < typename T >
bool nlua_rtti_unsigned_read( nv::lua::state* state, const type_entry*, void* object, int index )
{
        T* value = reinterpret_cast<T*>( object );
        if ( lua_type( state->get_raw(), index ) == LUA_TNUMBER )
        {
                *value = T( lua_tointeger( state->get_raw(), index ) );
                return true;
        }
        return false;
}

template < typename T >
bool nlua_rtti_floating_read( nv::lua::state* state, const type_entry*, void* object, int index )
{
        T* value = reinterpret_cast<T*>( object );
        if ( lua_type( state->get_raw(), index ) == LUA_TNUMBER )
        {
                *value = T( lua_tonumber( state->get_raw(), index ) );
                return true;
        }
        return false;
}

static bool nlua_rtti_boolean_read( nv::lua::state* state, const type_entry*, void* object, int index )
{
        bool* value = reinterpret_cast<bool*>( object );
        if ( lua_type( state->get_raw(), index ) == LUA_TBOOLEAN )
        {
                *value = lua_toboolean( state->get_raw(), index ) != 0;
                return true;
        }
        return false;
}


void nv::lua::type_data::insert( thash64 tid, lua_rtti_push_function p, lua_rtti_read_function r )
{
        m_type_read.assign( tid, r );
        m_type_push.assign( tid, p );
}

void nv::lua::type_data::register_standard_types()
{
        insert<bool>( nlua_rtti_boolean_push, nlua_rtti_boolean_read );
        insert<nv::sint8> ( nlua_rtti_signed_push<nv::sint8>,    nlua_rtti_signed_read<nv::sint8> );
        insert<nv::sint16>( nlua_rtti_signed_push<nv::sint16>,   nlua_rtti_signed_read<nv::sint16> );
        insert<nv::sint32>( nlua_rtti_signed_push<nv::sint32>,   nlua_rtti_signed_read<nv::sint32> );
        insert<nv::uint8> ( nlua_rtti_unsigned_push<nv::uint8>,  nlua_rtti_unsigned_read<nv::uint8> );
        insert<nv::uint16>( nlua_rtti_unsigned_push<nv::uint16>, nlua_rtti_unsigned_read<nv::uint16> );
        insert<nv::uint32>( nlua_rtti_unsigned_push<nv::uint32>, nlua_rtti_unsigned_read<nv::uint32> );
        insert<nv::f32>   ( nlua_rtti_floating_push<nv::f32>,    nlua_rtti_floating_read<nv::f32> );
        insert<nv::f64>   ( nlua_rtti_floating_push<nv::f64>,    nlua_rtti_floating_read<nv::f64> );
//      insert<nv::sint64>( nlua_rtti_floating_push<nv::sint64>, nlua_rtti_floating_read<nv::sint64> );
//      insert<nv::uint64>( nlua_rtti_floating_push<nv::uint64>, nlua_rtti_floating_read<nv::uint64> );
}