Files
lancet/structs/field.go
2024-01-29 11:00:50 +08:00

130 lines
2.9 KiB
Go

package structs
import (
"reflect"
"github.com/duke-git/lancet/v2/pointer"
)
// Field is abstract struct field for provide several high level functions
type Field struct {
Struct
field reflect.StructField
tag *Tag
}
func newField(v reflect.Value, f reflect.StructField, tagName string) *Field {
tag := f.Tag.Get(tagName)
field := &Field{
field: f,
tag: newTag(tag),
}
field.rvalue = v
field.rtype = v.Type()
field.TagName = tagName
return field
}
// Tag returns the value that the key in the tag string.
func (f *Field) Tag() *Tag {
return f.tag
}
// Value returns the underlying value of the field.
func (f *Field) Value() any {
return f.rvalue.Interface()
}
// IsEmbedded returns true if the given field is an embedded field.
func (f *Field) IsEmbedded() bool {
return len(f.field.Index) > 1
}
// IsExported returns true if the given field is exported.
func (f *Field) IsExported() bool {
return f.field.IsExported()
}
// IsZero returns true if the given field is zero value.
func (f *Field) IsZero() bool {
z := reflect.Zero(f.rvalue.Type()).Interface()
v := f.Value()
return reflect.DeepEqual(z, v)
}
// IsNil returns true if the given field is nil value.
func (f *Field) IsNil() bool {
v := f.Value()
if v == nil || (reflect.ValueOf(v)).Kind() == reflect.Ptr && reflect.ValueOf(v).IsNil() {
return true
}
return false
}
// Name returns the name of the given field
func (f *Field) Name() string {
return f.field.Name
}
// Kind returns the field's kind
func (f *Field) Kind() reflect.Kind {
return f.rvalue.Kind()
}
// IsSlice check if a struct field type is slice or not
func (f *Field) IsSlice() bool {
k := f.rvalue.Kind()
return k == reflect.Slice
}
// IsTargetType check if a struct field type is target type or not
func (f *Field) IsTargetType(targetType reflect.Kind) bool {
return f.rvalue.Kind() == targetType
}
// mapValue covert field value to map
func (f *Field) mapValue(value any) any {
val := pointer.ExtractPointer(value)
v := reflect.ValueOf(val)
var ret any
switch v.Kind() {
case reflect.Struct:
s := New(val)
s.TagName = f.TagName
m, _ := s.ToMap()
ret = m
case reflect.Map:
mapEl := v.Type().Elem()
switch mapEl.Kind() {
case reflect.Ptr, reflect.Array, reflect.Map, reflect.Slice, reflect.Chan:
// iterate the map
m := make(map[string]any, v.Len())
for _, key := range v.MapKeys() {
m[key.String()] = f.mapValue(v.MapIndex(key).Interface())
}
ret = m
default:
ret = v.Interface()
}
case reflect.Slice, reflect.Array:
sEl := v.Type().Elem()
switch sEl.Kind() {
case reflect.Ptr, reflect.Array, reflect.Map, reflect.Slice, reflect.Chan:
slices := make([]any, v.Len())
for i := 0; i < v.Len(); i++ {
slices[i] = f.mapValue(v.Index(i).Interface())
}
ret = slices
default:
ret = v.Interface()
}
default:
if v.Kind().String() != "invalid" {
ret = v.Interface()
}
}
return ret
}