package risk

import (
	"crypto/md5"
	"encoding/hex"
	"encoding/json"
	"strings"
	"time"

	"github.com/google/uuid"

	"github.com/spf13/cast"
)

func CheckSign(appID, appKey, random, sign string, ts int, data interface{}) bool {
	if int(time.Now().Unix())-ts > 120 {
		return false
	}

	v, _ := json.Marshal(data)

	m := md5.New()

	sb := strings.Builder{}
	sb.WriteString(appID)
	sb.WriteByte('-')
	sb.WriteString(cast.ToString(ts))
	sb.WriteByte('-')
	sb.Write(v)
	sb.WriteByte('-')
	sb.WriteString(random)
	sb.WriteByte('-')
	sb.WriteString(appKey)

	m.Write([]byte(sb.String()))
	md5str1 := hex.EncodeToString(m.Sum(nil))

	return md5str1 == sign
}

func Sign(appID, appKey string, data interface{}) (sign string, random string, ts int) {

	random = newRandom()

	ts = int(time.Now().Unix())

	v, _ := json.Marshal(data)

	m := md5.New()

	sb := strings.Builder{}
	sb.WriteString(appID)
	sb.WriteByte('-')
	sb.WriteString(cast.ToString(ts))
	sb.WriteByte('-')
	sb.Write(v)
	sb.WriteByte('-')
	sb.WriteString(random)
	sb.WriteByte('-')
	sb.WriteString(appKey)

	m.Write([]byte(sb.String()))
	sign = hex.EncodeToString(m.Sum(nil))
	return
}

func newRandom() string {
	uuid := uuid.Must(uuid.NewRandom())
	random := uuid.String()
	return strings.ReplaceAll(random, "-", "")
}