package request

import (
	"git.sxidc.com/go-framework/baize/domain"
	"git.sxidc.com/go-framework/baize/tag/assign"
	"git.sxidc.com/go-tools/utils/reflectutils"
	"git.sxidc.com/service-supports/fserr"
	"reflect"
)

type DTO interface{}

func AssignDTOToDomainObject(dto DTO, domainObject domain.Object) error {
	return assign.DefaultUsage(dto, domainObject)
}

func Field[T any](dto DTO, fieldName string) (T, error) {
	var zero T

	if dto == nil {
		return zero, fserr.New("DTO为nil")
	}

	fieldValue, err := getDTOFieldValue(dto, fieldName)
	if err != nil {
		return zero, err
	}

	if !fieldValue.IsValid() {
		return zero, fserr.New("dto" + fieldValue.Type().String() + "的字段" + fieldName + "无法赋值")
	}

	retValue, ok := fieldValue.Interface().(T)
	if !ok {
		return zero, fserr.New("dto" + fieldValue.Type().String() + "的字段" + fieldName + "无法转换类型")
	}

	return retValue, nil
}

func ToConcrete[T DTO](dto DTO) (T, error) {
	var zero T

	if dto == nil {
		return zero, fserr.New("DTO为nil")
	}

	concrete, ok := dto.(T)
	if !ok {
		return zero, fserr.New("DTO转化失败")
	}

	return concrete, nil
}

func getDTOFieldValue(dto DTO, fieldName string) (*reflect.Value, error) {
	if dto == nil {
		return nil, fserr.New("DTO为nil")
	}

	dtoValue := reflect.ValueOf(dto)

	if reflectutils.IsValueStructOrStructPointer(dtoValue) {
		return nil, fserr.New("dto必须是结构或结构指针")
	}

	fieldValue := reflectutils.PointerValueElem(dtoValue).FieldByName(fieldName)

	return &fieldValue, nil
}