forked from beatgammit/luna
/
marshal.go
204 lines (178 loc) · 4.98 KB
/
marshal.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
package luna
import (
"encoding"
"fmt"
"reflect"
"strings"
)
type LuaValue interface {
Unmarshal(interface{}) error
}
func convertBasic(src LuaValue, dst interface{}) error {
var destVal reflect.Value
var ok bool
if destVal, ok = dst.(reflect.Value); !ok {
destVal = reflect.ValueOf(dst)
if destVal.Type().Kind() != reflect.Ptr {
return fmt.Errorf("Must pass a pointer type to Unmarshal")
}
}
if v, ok := src.(LuaString); ok {
dst := destVal.Interface()
if unmarshaler, ok := dst.(encoding.TextUnmarshaler); ok {
return unmarshaler.UnmarshalText([]byte(v))
}
dst = reflect.Indirect(destVal).Interface()
if unmarshaler, ok := dst.(encoding.TextUnmarshaler); ok {
return unmarshaler.UnmarshalText([]byte(v))
}
}
destVal = reflect.Indirect(destVal)
destType := destVal.Type()
srcVal := reflect.ValueOf(src)
if !srcVal.Type().ConvertibleTo(destType) {
return fmt.Errorf("Cannot assign '%s' to '%s': given = %v", srcVal.Type(), destType, src)
}
destVal.Set(srcVal.Convert(destType))
return nil
}
type LuaNumber float64
func (lv LuaNumber) Unmarshal(d interface{}) error {
return convertBasic(lv, d)
}
type LuaBool bool
func (lv LuaBool) Unmarshal(d interface{}) error {
return convertBasic(lv, d)
}
type LuaString string
func (lv LuaString) Unmarshal(d interface{}) error {
return convertBasic(lv, d)
}
// the type here isn't significant, as long as it's nil-able
type LuaNil []int
func (lv LuaNil) Unmarshal(d interface{}) error {
destVal := reflect.ValueOf(d)
if destVal.Type().Kind() != reflect.Ptr {
return fmt.Errorf("Must pass a pointer type to Unmarshal")
}
switch destVal.Type().Kind() {
// I don't think lua can return a pointer or an interface,
// but it's not hurting anything
case reflect.Ptr, reflect.Map, reflect.Slice, reflect.Interface:
destVal.Elem().Set(reflect.Zero(destVal.Elem().Type()))
default:
return fmt.Errorf("Unmarshal unsupported for %T", d)
}
return nil
}
type LuaTable struct {
indexed map[float64]LuaValue
mapped map[string]LuaValue
booled map[bool]LuaValue
}
func (lv LuaTable) GetIndex(i float64) LuaValue {
return lv.indexed[i]
}
func (lv LuaTable) Get(i string) LuaValue {
return lv.mapped[i]
}
func (lv LuaTable) Map() map[string]LuaValue {
return lv.mapped
}
func (lv LuaTable) Slice() (ret []LuaValue) {
for i := 1; i <= len(lv.indexed); i++ {
if v, ok := lv.indexed[float64(i)]; ok {
ret = append(ret, v)
} else {
break
}
}
return
}
func convertTableVal(src LuaValue, d interface{}) error {
if _, ok := src.(LuaTable); ok {
return src.Unmarshal(d)
}
return convertBasic(src, d)
}
func setMap(destVal reflect.Value, k interface{}, v LuaValue, destType reflect.Type) error {
dest := reflect.New(destType.Elem())
if err := convertTableVal(v, dest.Interface()); err != nil {
return err
}
destVal.SetMapIndex(reflect.ValueOf(k), dest.Elem())
return nil
}
func (lv LuaTable) Unmarshal(d interface{}) (err error) {
var destVal reflect.Value
var ok bool
if destVal, ok = d.(reflect.Value); !ok {
destVal = reflect.ValueOf(d)
if destVal.Type().Kind() != reflect.Ptr {
return fmt.Errorf("Must pass a pointer type to Unmarshal")
}
}
destVal = reflect.Indirect(destVal)
destType := destVal.Type()
switch k := destType.Kind(); k {
case reflect.Slice, reflect.Array:
items := lv.Slice()
if k == reflect.Slice {
// recreate or change length of slice to fit our items
if destVal.Len() >= len(items) || destVal.Cap() >= len(items) {
destVal.SetLen(len(items))
} else {
destVal.Set(reflect.MakeSlice(destType, len(items), len(items)))
}
} else if destVal.Len() < len(items) {
return fmt.Errorf("Array not big enough to hold values; needed '%d', have '%d'", len(items), destVal.Len())
}
for i, v := range items {
dest := reflect.New(destType.Elem())
if er := convertTableVal(v, dest.Interface()); er != nil {
err = er
} else {
destVal.Index(i).Set(dest.Elem())
}
}
case reflect.Struct:
// TODO: find a better way to check for a non-existant field
zero := reflect.Value{}
for k, v := range lv.mapped {
field := destVal.FieldByName(strings.Title(k))
if field == zero {
continue
}
if er := convertTableVal(v, field); err != nil {
err = er
}
}
case reflect.Map:
if destVal.IsNil() {
destVal.Set(reflect.MakeMap(destType))
}
keyType := destType.Key()
if keyType.Kind() >= reflect.Int && keyType.Kind() <= reflect.Complex128 {
for k, v := range lv.indexed {
setMap(destVal, k, v, destType)
}
} else if keyType.Kind() == reflect.String {
for k, v := range lv.mapped {
setMap(destVal, k, v, destType)
}
} else if keyType.Kind() == reflect.Bool {
for k, v := range lv.booled {
setMap(destVal, k, v, destType)
}
} else if keyType.Kind() == reflect.Struct {
return fmt.Errorf("Struct key types not currently supported")
} else {
return fmt.Errorf("Invalid key type: %s", keyType)
}
}
return nil
}
type luaTypeError string
func (lv luaTypeError) Unmarshal(interface{}) error {
return fmt.Errorf("%s", lv)
}