package datacenter_client

import (
	"bytes"
	"crypto/md5"
	"encoding/hex"
	"encoding/json"
	"fmt"
	"io/ioutil"
	"metawant.greentech.com.cn/gaoyagang/gt-common/httplib"
	"net/http"
	"net/url"
	"sort"
	"time"
)

type DcApiClient struct {
	ServerIp string
	AppName string
	AppSecret string
}

const (
	S2_MIN_LENGTH           = 2048
	S2_HEAD_LENGTH          = 200
	S2_TAIL_LENGTH          = 200
)

func CreateDcApiClient(ip, appName, appSecret string) *DcApiClient {
	return &DcApiClient{
		ServerIp: ip,
		AppName: appName,
		AppSecret: appSecret,
	}
}

func (d *DcApiClient) RequestMiddleProcess(h *httplib.HTTPRequest, projectId string) ([]byte, error) {
	//h.Header("X-Forwarded-For", "127.0.0.1")
	h.Header("APP-NAME", d.AppName)
	ts := time.Now().Unix()
	h.Param("project_id", projectId)
	h.Param("ts", fmt.Sprintf("%d", ts))
	sign := d.CreateSign(h)
	h.Param("sign", sign)
	return h.Bytes()
}

func (d *DcApiClient)CreateSign(h *httplib.HTTPRequest) string {
	s2, err := parseBody(h)
	if err != nil {
		fmt.Println("parseBody Error: ", err.Error())
	}
	contentLength := h.GetRequest().ContentLength
	if contentLength > S2_MIN_LENGTH {
		h.Param("sign_flag", "1")
		s2 = cutS2(s2)
	} else {
		s2, _ = sortS2(s2)
	}


	s3 := contentLength
	s1 := parseQuery(h)

	m := md5.New()
	m.Write([]byte(fmt.Sprintf("%s%s%d%s", s1, s2, s3, d.AppSecret)))
	md5Str := hex.EncodeToString(m.Sum(nil))
	//fmt.Println("s1", s1)
	//fmt.Println("s2", s2)
	//fmt.Println("s3", s3)
	//fmt.Println("md5", md5Str)
	return md5Str
}

func cutS2(s2 string) string {
	s2l := len(s2)
	//if s2l <= S2_MIN_LENGTH {
	//	return s2
	//}
	return fmt.Sprintf("%s%s", s2[:S2_HEAD_LENGTH], s2[s2l-S2_TAIL_LENGTH:])
}

func sortS2(s2 string) (string, error) {
	var mi map[string]interface{}
	if err := json.Unmarshal([]byte(s2), &mi); err != nil {
		return "", err
	}

	smi := SortMapByKey(mi)

	if bs, err := json.Marshal(smi); err != nil {
		return "", err
	} else {
		return string(bs), nil
	}
}

func parseBody(r *httplib.HTTPRequest) (s2 string, err error) {
	if r.GetRequest().Method == http.MethodGet {
		return "", nil
	}
	body := r.GetRequest().Body

	cnt, _ := ioutil.ReadAll(body)
	r.GetRequest().Body = ioutil.NopCloser(bytes.NewReader(cnt))

	return string(cnt), nil
}

func parseQuery(r *httplib.HTTPRequest) string {
	params := r.GetQueryParam()
	delete(params, "sign")

	val := url.Values{}
	for k, v := range params {
		for index, s := range v {
			if index == 0 {
				val.Set(k, s)
			} else {
				val.Add(k, s)
			}
		}
	}
	return val.Encode()
}

// SortMapByKey 对 map[string]interface{} 按照键进行排序
func SortMapByKey(m map[string]interface{}) map[string]interface{} {
	// 创建一个 map[string]int，用于记录键的索引
	indexMap := make(map[string]int)
	for k := range m {
		indexMap[k] = len(indexMap)
	}

	// 对键进行排序
	keys := make([]string, 0, len(indexMap))
	for k := range indexMap {
		keys = append(keys, k)
	}
	sort.Strings(keys)

	// 创建排序后的 map[string]interface{}
	sortedMap := make(map[string]interface{})
	for _, k := range keys {
		sortedMap[k] = m[k]
	}

	return sortedMap
}