package middlewares

import (
	"crypto/md5"
	"encoding/hex"
	"encoding/json"
	"fmt"
	"sort"
	"strings"

	common "com.snow.auto_monitor/app/http/controllers"
	mermod "com.snow.auto_monitor/app/models/merchant"
	"github.com/gin-gonic/gin"
	"github.com/qit-team/snow-core/log/logger"
)

type Verify struct {
	MerchantId int64  `json:"merchant_id" validate:"required"`
	TimeStamp  int64  `json:"time_stamp" validate:"required"`
	Sign       string `json:"sign" validate:"required"`
}

func getMD5Hash(input string) string {
	hash := md5.Sum([]byte(input))
	return hex.EncodeToString(hash[:])
}

func GenMD5Sign(data map[string]interface{}, secretKey string) string {
	keys := make([]string, 0, len(data))
	for key := range data {
		if key != "sign" && key != "Sign" {
			keys = append(keys, key)
		}
	}
	sort.Strings(keys)

	rawStr := ""
	for _, key := range keys {
		value := fmt.Sprintf("%v", data[key])
		if rawStr != "" {
			rawStr += "&"
		}
		rawStr += fmt.Sprintf("%s=%s", key, value)
	}
	rawStr += "&key=" + secretKey
	sign := strings.ToUpper(getMD5Hash(rawStr))
	return sign
}

func VerifySign() gin.HandlerFunc {
	return func(c *gin.Context) {
		var data map[string]interface{}
		body, err := common.ReadBody(c)
		if err != nil {
			common.Error(c, 400, err.Error())
			c.Abort()
			return
		}
		err = json.Unmarshal(body, &data)
		if err != nil {
			common.Error(c, 400, err.Error())
			c.Abort()
			return
		}
		if data["merchant_id"] == nil || data["time_stamp"] == nil || data["sign"] == nil {
			common.Error(c, 400, "参数错误")
			c.Abort()
			return
		}
		//验证商户是否存在
		merchanId := int64(data["merchant_id"].(float64))
		merchant, has, err := mermod.GetInstance().GetById(merchanId)
		if err != nil {
			common.Error500(c)
			c.Abort()
			return
		}
		if !has {
			common.Error(c, 400, "商户不存在")
			c.Abort()
			return
		}
		//验证签名是否正确
		hash := GenMD5Sign(data, merchant.Key)
		logger.Info(c, "Sign", hash)
		if hash != data["sign"] {
			common.Error(c, 400, "签名错误")
			c.Abort()
			return
		}
	}
}