package tools

import (
	"fmt"
	"reflect"
	"strings"
)

// 结构体转 map[string]interface{}
func StructToMap(object interface{}, tagName string) (map[string]interface{}, error) {
	var err error
	objectType := reflect.TypeOf(object)
	objectValue := reflect.ValueOf(object)

	if objectValue.Kind() == reflect.Ptr {
		objectValue = objectValue.Elem()
		objectType = objectType.Elem()
	}
	if objectValue.Kind() != reflect.Struct {
		return nil, fmt.Errorf("数据类型错误")
	}

	objectNum := objectType.NumField()
	m := make(map[string]interface{}, objectNum)

	for i := 0; i < objectNum; i++ {
		key := ""
		keyl := strings.Split(objectType.Field(i).Tag.Get(tagName), ",")
		if len(keyl) >= 1 {
			key = keyl[0]
		}
		if tagName == "" {
			key = objectType.Field(i).Name
		}
		if key != "" && key != "-" {
			v := objectValue.Field(i)
			switch v.Kind() {
			case reflect.Array, reflect.Slice:
				l := make([]interface{}, 0, v.Len())
				for s := 0; s < v.Len(); s++ {
					sv, err := StructToMap(v.Index(s).Interface(), tagName)
					if err != nil {
						return nil, err
					}
					l = append(l, sv)
				}
				m[key] = l
			case reflect.Map:
				mm := make(map[string]interface{}, v.Len())
				for _, k := range v.MapKeys() {
					if mm[k.String()], err = StructToMap(v.MapIndex(k), tagName); err != nil {
						return nil, err
					}
				}
				m[key] = mm
			case reflect.Struct:
				vv, err := StructToMap(v.Interface(), tagName)
				if err != nil {
					return nil, err
				}
				m[key] = vv
			default:
				m[key] = objectValue.Field(i).Interface()
			}
		}
	}
	return m, nil

}

// 根据标签取出结构体所有key
func GetStructKeys(s any, tag string) ([]string, error) {
	st := reflect.TypeOf(s)
	sv := reflect.ValueOf(s)
	if sv.Kind() == reflect.Ptr {
		st = st.Elem()
	}
	if st.Kind() != reflect.Struct {
		return []string{}, fmt.Errorf("%v TypeError", s)
	}

	kl := make([]string, 0)
	for i := 0; i < st.NumField(); i++ {
		key := ""
		keyl := strings.Split(st.Field(i).Tag.Get(tag), ",")
		if len(keyl) >= 1 {
			key = keyl[0]
		}
		if tag == "" {
			key = st.Field(i).Name
		}
		if key != "" && key != "-" {
			kl = append(kl, key)
		}
	}
	return kl, nil
}