package middleware

import (
	"bytes"
	"encoding/json"
	"io"
	"net/http"
	"rs/cmd/api/internal/config"
	"rs/untils/response"
	"rs/untils/sign"
)

type SignMiddleware struct {
	c *config.Config
}

func NewSignMiddleware(c *config.Config) *SignMiddleware {
	return &SignMiddleware{
		c: c,
	}
}

func (m *SignMiddleware) Handle(next http.HandlerFunc) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		var (
			reqDataMap map[string]interface{}
		)

		originalBody, err := io.ReadAll(r.Body)
		reqData := make([]byte, len(originalBody))
		copy(reqData, originalBody)
		r.Body = io.NopCloser(bytes.NewReader(originalBody))
		if err != nil {
			response.Err(w, response.HTTP_AUTH_FAIL, "获取请求参数失败")
		}
		err = json.Unmarshal(reqData, &reqDataMap)
		if err != nil {
			response.Err(w, response.HTTP_AUTH_FAIL, "获取请求参数失败")
		}
		if _, ok := reqDataMap["sign"]; !ok {
			response.Err(w, response.HTTP_AUTH_FAIL, "未找到签名字段")
		}
		if _, ok := reqDataMap["sign"]; !ok {
			response.Err(w, response.HTTP_AUTH_FAIL, err.Error())
		}
		signString := reqDataMap["sign"].(string)
		sysSign, err := sign.GetSign(reqDataMap, m.c.Sys.Key)
		if sysSign != signString {
			response.Err(w, response.HTTP_AUTH_FAIL, "签名不正确")
			return
		}
		next(w, r)
	}
}