package RouterManchong

import (
	"crypto/md5"
	"encoding/hex"
	"errors"
	"manchong"
	"time"
)

type head struct {
	VERSION   string `json:"VERSION"`
	TIMESTAMP string `json:"TIMESTAMP"`
	SEQNO     string `json:"SEQNO"`
	APPID     string `json:"APPID"`
	SECERTKEY string `json:"SECERTKEY"`
}

func (h *head) check() (string, error) {
	n := len(h.TIMESTAMP)
	if n < 15 {
		return "14", errors.New("TIMESTAMP超过时限")
	}
	s := h.TIMESTAMP[:14] + "." + h.TIMESTAMP[14:]
	t, err := time.ParseInLocation("20060102150405.999999999", s, time.Local)

	if err != nil {
		return "99", err
	}
	bigt := time.Now().Add(5 * time.Minute)
	lowt := time.Now().Add(-5 * time.Minute)
	if t.Before(lowt) || t.After(bigt) {
		return "14", errors.New("TIMESTAMP超过时限")
	}
	appc, ok := manchong.CFG.Users[h.APPID]
	if !ok {
		return "09", errors.New("APPID已经失效")
	}
	m5 := md5.New()
	m5.Write([]byte(h.TIMESTAMP + h.SEQNO + h.APPID + appc))
	s = hex.EncodeToString(m5.Sum(nil))
	if s != h.SECERTKEY {
		return "08", errors.New("签名验证失败")
	}
	return "00", nil
}

type template struct {
	HEADER  *head       `json:"HEADER"`
	MSGBODY interface{} `json:"MSGBODY"`
}