map.go

package utils

import (
	"bytes"
	"encoding/json"
	"sort"
	"time"
)

type OrderedMap struct {
	Order []string
	Map   map[string]any
}

func GetTime() int64 {
	return time.Now().UnixMilli()
}

func (om *OrderedMap) UnmarshalJSON(b []byte) error {
	json.Unmarshal(b, &om.Map)

	index := make(map[string]int)
	for key := range om.Map {
		om.Order = append(om.Order, key)
		esc, _ := json.Marshal(key) //Escape the key
		index[key] = bytes.Index(b, esc)
	}

	sort.Slice(om.Order, func(i, j int) bool { return index[om.Order[i]] < index[om.Order[j]] })
	return nil
}

func (om OrderedMap) MarshalJSON() ([]byte, error) {
	var b []byte
	buf := bytes.NewBuffer(b)
	buf.WriteRune('{')
	l := len(om.Order)
	for i, key := range om.Order {
		km, err := json.Marshal(key)
		if err != nil {
			return nil, err
		}
		buf.Write(km)
		buf.WriteRune(':')
		vm, err := json.Marshal(om.Map[key])
		if err != nil {
			return nil, err
		}
		buf.Write(vm)
		if i != l-1 {
			buf.WriteRune(',')
		}
	}
	buf.WriteRune('}')
	return buf.Bytes(), nil
}