func callGoMethod(L *lua.State, name string, st reflect.Value) {
ret := st.MethodByName(name)
if !ret.IsValid() {
fmt.Println("whoops")
}
L.PushGoFunction(GoLuaFunc(L, ret))
}
func GoLua(L *lua.State) int {
go func() {
LT := L.NewThread()
L.PushValue(1)
lua.XMove(L, LT, 1)
res := LT.Resume(0)
for res != 0 {
if res == 2 {
emsg := LT.ToString(-1)
fmt.Println("error", emsg)
}
ch, t := valueOfProxy(LT, -2)
if LT.ToBoolean(-1) { // send on a channel
val := valueOf(LuaToGo(LT, t.Elem(), -3))
ch.Send(val)
res = LT.Resume(0)
} else { // receive on a channel
val, ok := ch.Recv()
GoToLua(LT, t.Elem(), val)
LT.PushBoolean(ok)
res = LT.Resume(2)
}
}
}()
return 0
}
func slice__newindex(L *lua.State) int {
slice, t := valueOfProxy(L, 1)
idx := L.ToInteger(2)
val := LuaToGo(L, t.Elem(), 3)
slice.Index(idx - 1).Set(valueOf(val))
return 0
}
func slice_slice(L *lua.State) int {
slice, _ := valueOfProxy(L, 1)
i1, i2 := L.ToInteger(2), L.ToInteger(3)
newslice := slice.Slice(i1, i2)
makeValueProxy(L, newslice, SLICE_META)
return 1
}
func struct__newindex(L *lua.State) int {
st, t := valueOfProxy(L, 1)
name := L.ToString(2)
if t.Kind() == reflect.Ptr {
st = st.Elem()
}
field := st.FieldByName(name)
val := LuaToGo(L, field.Type(), 3)
field.Set(valueOf(val))
return 0
}
// GoLuaFunc converts an arbitrary Go function into a Lua-compatible GoFunction.
// There are special optimized cases for functions that go from strings to strings,
// and doubles to doubles, but otherwise Go
// reflection is used to provide a generic wrapper function
func GoLuaFunc(L *lua.State, fun interface{}) lua.LuaGoFunction {
switch f := fun.(type) {
case func(*lua.State) int:
return f
case func(string) string:
return func(L *lua.State) int {
L.PushString(f(L.ToString(1)))
return 1
}
case func(float64) float64:
return func(L *lua.State) int {
L.PushNumber(f(L.ToNumber(1)))
return 1
}
default:
}
var funv reflect.Value
switch ff := fun.(type) {
case reflect.Value:
funv = ff
default:
funv = valueOf(fun)
}
funt := funv.Type()
targs, tout := functionArgRetTypes(funt)
return func(L *lua.State) int {
var lastT reflect.Type
isVariadic := funt.IsVariadic()
if isVariadic {
lastT = targs[len(targs)-1].Elem()
targs = targs[0 : len(targs)-1]
}
args := make([]reflect.Value, len(targs))
for i, t := range targs {
val := LuaToGo(L, t, i+1)
args[i] = valueOf(val)
}
if isVariadic {
n := L.GetTop()
for i := len(targs) + 1; i <= n; i++ {
val := valueOf(LuaToGo(L, lastT, i))
args = append(args, val)
}
}
resv := funv.Call(args)
for i, val := range resv {
GoToLua(L, tout[i], val)
}
return len(resv)
}
}
func struct__index(L *lua.State) int {
st, t := valueOfProxy(L, 1)
name := L.ToString(2)
est := st
if t.Kind() == reflect.Ptr {
est = st.Elem()
}
ret := est.FieldByName(name)
if !ret.IsValid() { // no such field, try for method?
callGoMethod(L, name, st)
} else {
GoToLua(L, ret.Type(), ret)
}
return 1
}
// copy a Go slice to a Lua table
func CopySliceToTable(L *lua.State, vslice reflect.Value) int {
if vslice.IsValid() && vslice.Type().Kind() == reflect.Slice {
n := vslice.Len()
L.CreateTable(n, 0)
for i := 0; i < n; i++ {
L.PushInteger(int64(i + 1))
GoToLua(L, nil, vslice.Index(i))
L.SetTable(-3)
}
return 1
} else {
L.PushNil()
L.PushString("not a slice!")
}
return 2
}
// look up a Lua value by its full name. If idx is 0, then this name
// is assumed to start in the global table, e.g. "string.gsub".
// With non-zero idx, can be used to look up subfields of a table
func Lookup(L *lua.State, path string, idx int) {
parts := strings.Split(path, ".")
if idx != 0 {
L.PushValue(idx)
} else {
L.GetGlobal("_G")
}
for _, field := range parts {
L.GetField(-1, field)
L.Remove(-2) // remove table
}
}
func makeValueProxy(L *lua.State, val reflect.Value, proxyMT string) {
rawptr := L.NewUserdata(uintptr(unsafe.Sizeof(ValueProxy{})))
ptr := (*ValueProxy)(rawptr)
ptr.value = val
ptr.t = val.Type()
L.LGetMetaTable(proxyMT)
L.SetMetaTable(-2)
}
// copy a Go map to a Lua table
func CopyMapToTable(L *lua.State, vmap reflect.Value) int {
if vmap.IsValid() && vmap.Type().Kind() == reflect.Map {
n := vmap.Len()
L.CreateTable(0, n)
for _, key := range vmap.MapKeys() {
val := vmap.MapIndex(key)
GoToLua(L, nil, key)
GoToLua(L, nil, val)
L.SetTable(-3)
}
return 1
} else {
L.PushNil()
L.PushString("not a map!")
}
return 2
}
func slice__index(L *lua.State) int {
slice, _ := valueOfProxy(L, 1)
if L.IsNumber(2) {
idx := L.ToInteger(2)
ret := slice.Index(idx - 1)
GoToLua(L, ret.Type(), ret)
} else {
name := L.ToString(2)
switch name {
case "Slice":
L.PushGoFunction(slice_slice)
default:
fmt.Println("unknown slice method")
}
}
return 1
}
func channel_send(L *lua.State) int {
fmt.Println("yield send")
L.PushValue(2)
L.PushValue(1)
L.PushBoolean(true)
return L.Yield(3)
//~ ch,t := valueOfProxy(L,1)
//~ val := valueOf(LuaToGo(L, t.Elem(),2))
//~ ch.Send(val)
//~ return 0
}
func CopyTableToStruct(L *lua.State, t reflect.Type, idx int) interface{} {
if t.Kind() == reflect.Ptr {
t = t.Elem()
}
s := reflect.New(t) // T -> *T
ref := s.Elem()
L.PushNil()
if idx < 0 {
idx--
}
for L.Next(idx) != 0 {
key := L.ToString(-2)
f := ref.FieldByName(key)
if f.IsValid() {
val := valueOf(LuaToGo(L, f.Type(), -1))
f.Set(val)
}
L.Pop(1)
}
return s.Interface()
}
func channel_recv(L *lua.State) int {
fmt.Println("yield recv")
L.PushValue(1)
L.PushBoolean(false)
return L.Yield(2)
//~ ch,t := valueOfProxy(L,1)
//~ L.Yield(0)
//~ val,ok := ch.Recv()
//~ GoToLua(L,t.Elem(),val)
//~ L.PushBoolean(ok)
//~ L.Resume(0)
//~ return 2
}
// return the Lua table at 'idx' as a copied Go slice. If 't' is nil then the slice
// type is []interface{}
func CopyTableToSlice(L *lua.State, t reflect.Type, idx int) interface{} {
if t == nil {
t = reflect.TypeOf(tslice)
}
te := t.Elem()
n := int(L.ObjLen(idx))
slice := reflect.MakeSlice(t, n, n)
for i := 1; i <= n; i++ {
L.RawGeti(idx, i)
val := LuaToGo(L, te, -1)
slice.Index(i - 1).Set(valueOf(val))
L.Pop(1)
}
return slice.Interface()
}
// return the Lua table at 'idx' as a copied Go map. If 't' is nil then the map
// type is map[string]interface{}
func CopyTableToMap(L *lua.State, t reflect.Type, idx int) interface{} {
if t == nil {
t = reflect.TypeOf(tmap)
}
te, tk := t.Elem(), t.Key()
m := reflect.MakeMap(t)
L.PushNil()
if idx < 0 {
idx--
}
for L.Next(idx) != 0 {
// key at -2, value at -1
key := valueOf(LuaToGo(L, tk, -2))
val := valueOf(LuaToGo(L, te, -1))
m.SetMapIndex(key, val)
L.Pop(1)
}
return m.Interface()
}
func slicemap__len(L *lua.State) int {
val, _ := valueOfProxy(L, 1)
L.PushInteger(int64(val.Len()))
return 1
}
// create a new LuaObject using the given state and stack index.
func NewLuaObject(L *lua.State, idx int) *LuaObject {
tp := L.LTypename(idx)
L.PushValue(idx)
ref := L.Ref(lua.LUA_REGISTRYINDEX)
return &LuaObject{L, ref, tp}
}
func interface__index(L *lua.State) int {
st, _ := valueOfProxy(L, 1)
name := L.ToString(2)
callGoMethod(L, name, st)
return 1
}
func register(L *lua.State, table string, values Map, convertFun bool) {
pop := true
if table == "*" {
pop = false
} else if len(table) > 0 {
L.GetGlobal(table)
if L.IsNil(-1) {
L.NewTable()
L.SetGlobal(table)
L.GetGlobal(table)
}
} else {
L.GetGlobal("_G")
}
for name, val := range values {
t := reflect.TypeOf(val)
if t.Kind() == reflect.Func {
if convertFun {
L.PushGoFunction(GoLuaFunc(L, val))
} else {
lf := val.(func(*lua.State) int)
L.PushGoFunction(lf)
}
} else {
GoToLua(L, t, valueOf(val))
}
L.SetField(-2, name)
}
if pop {
L.Pop(1)
}
}
// Convert a Lua value 'idx' on the stack to the Go value of desired type 't'. Handles
// numerical and string types in a straightforward way, and will convert tables to
// either map or slice types.
func LuaToGo(L *lua.State, t reflect.Type, idx int) interface{} {
var value interface{}
var kind reflect.Kind
if t == nil { // let the Lua type drive the conversion...
switch L.Type(idx) {
case lua.LUA_TNIL:
return nil // well, d'oh
case lua.LUA_TBOOLEAN:
kind = reflect.Bool
case lua.LUA_TSTRING:
kind = reflect.String
case lua.LUA_TTABLE:
kind = reflect.Interface
default:
return NewLuaObject(L, idx)
}
} else if t.Kind() == reflect.Ptr {
kind = t.Elem().Kind()
} else {
kind = t.Kind()
}
switch kind {
// various numerical types are tedious but straightforward
case reflect.Float64:
{
ptr := new(float64)
*ptr = L.ToNumber(idx)
value = *ptr
}
case reflect.Float32:
{
ptr := new(float32)
*ptr = float32(L.ToNumber(idx))
value = *ptr
}
case reflect.Int:
{
ptr := new(int)
*ptr = int(L.ToNumber(idx))
value = *ptr
}
case reflect.Int8:
{
ptr := new(byte)
*ptr = byte(L.ToNumber(idx))
value = *ptr
}
case reflect.String:
{
tos := L.ToString(idx)
ptr := new(string)
*ptr = tos
value = *ptr
}
case reflect.Bool:
{
ptr := new(bool)
*ptr = bool(L.ToBoolean(idx))
value = *ptr
}
case reflect.Slice:
{
// if we get a table, then copy its values to a new slice
if L.IsTable(idx) {
value = CopyTableToSlice(L, t, idx)
} else {
value = unwrapProxy(L, idx)
}
}
case reflect.Map:
{
if L.IsTable(idx) {
value = CopyTableToMap(L, t, idx)
} else {
value = unwrapProxy(L, idx)
}
}
case reflect.Struct:
{
if L.IsTable(idx) {
value = CopyTableToStruct(L, t, idx)
} else {
value = unwrapProxy(L, idx)
}
}
case reflect.Interface:
{
if L.IsTable(idx) {
// have to make an executive decision here: tables with non-zero
// length are assumed to be slices!
if L.ObjLen(idx) > 0 {
value = CopyTableToSlice(L, nil, idx)
} else {
value = CopyTableToMap(L, nil, idx)
}
} else if L.IsNumber(idx) {
value = L.ToNumber(idx)
} else if L.IsString(idx) {
value = L.ToString(idx)
} else if L.IsBoolean(idx) {
value = L.ToBoolean(idx)
} else {
value = unwrapProxy(L, idx)
}
}
default:
{
fmt.Println("unhandled type", t)
value = 20
}
}
return value
}
func isValueProxy(L *lua.State, idx int) bool {
res := false
if L.IsUserdata(idx) {
L.GetMetaTable(idx)
if !L.IsNil(-1) {
L.GetField(-1, "luago.value")
res = !L.IsNil(-1)
L.Pop(1)
}
L.Pop(1)
}
return res
}
// Push a Go value 'val' of type 't' on the Lua stack.
// If we haven't been given a concrete type, use the type of the value
// and unbox any interfaces.
func GoToLua(L *lua.State, t reflect.Type, val reflect.Value) {
proxify := true
if !val.IsValid() || val.IsNil() {
L.PushNil()
return
}
if t == nil {
t = val.Type()
if t.Kind() == reflect.Interface { // unbox interfaces!
val = valueOf(val.Interface())
t = val.Type()
}
proxify = false
}
if t.Kind() == reflect.Ptr {
t = t.Elem()
}
switch t.Kind() {
case reflect.Float64:
case reflect.Float32:
{
L.PushNumber(val.Float())
}
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32:
{
L.PushNumber(float64(val.Int()))
}
case reflect.Uint, reflect.Uint8:
{
L.PushNumber(float64(val.Uint()))
}
case reflect.String:
{
L.PushString(val.String())
}
case reflect.Bool:
{
L.PushBoolean(val.Bool())
}
case reflect.Slice:
{
if proxify {
makeValueProxy(L, val, SLICE_META)
} else {
CopySliceToTable(L, val)
}
}
case reflect.Map:
{
if proxify {
makeValueProxy(L, val, MAP_META)
} else {
CopyMapToTable(L, val)
}
}
case reflect.Struct:
{
if v, ok := val.Interface().(error); ok {
L.PushString(v.Error())
} else {
makeValueProxy(L, val, STRUCT_META)
}
}
default:
{
if v, ok := val.Interface().(error); ok {
L.PushString(v.Error())
} else if val.IsNil() {
L.PushNil()
} else {
makeValueProxy(L, val, INTERFACE_META)
}
}
}
}
func valueOfProxy(L *lua.State, idx int) (reflect.Value, reflect.Type) {
vp := (*ValueProxy)(L.ToUserdata(idx))
return vp.value, vp.t
}
// Add a callback to the lua state.
func addCallback(L *lua.State, name string, args []interface{}) {
L.GetGlobal("callbacks")
luar.GoToLua(L, reflect.TypeOf(args), reflect.ValueOf(args))
L.SetField(-2, name)
}
func initializeProxies(L *lua.State) {
flagValue := func() {
L.PushBoolean(true)
L.SetField(-2, "luago.value")
L.Pop(1)
}
L.NewMetaTable(SLICE_META)
L.SetMetaMethod("__index", slice__index)
L.SetMetaMethod("__newindex", slice__newindex)
L.SetMetaMethod("__len", slicemap__len)
flagValue()
L.NewMetaTable(MAP_META)
L.SetMetaMethod("__index", map__index)
L.SetMetaMethod("__newindex", map__newindex)
L.SetMetaMethod("__len", slicemap__len)
flagValue()
L.NewMetaTable(STRUCT_META)
L.SetMetaMethod("__index", struct__index)
L.SetMetaMethod("__newindex", struct__newindex)
flagValue()
L.NewMetaTable(INTERFACE_META)
L.SetMetaMethod("__index", interface__index)
flagValue()
L.NewMetaTable(CHANNEL_META)
//~ RegisterFunctions(L,"*",FMap {
//~ "Send":channel_send,
//~ "Recv":channel_recv,
//~ })
L.NewTable()
L.PushGoFunction(channel_send)
L.SetField(-2, "Send")
L.PushGoFunction(channel_recv)
L.SetField(-2, "Recv")
L.SetField(-2, "__index")
flagValue()
}
