package api

import (
	"encoding/json"
	"log"
	"net/http"
	"strconv"
	"strings"
)

const (
	Error_code      = 0
	Error_code_1001 = 1001
	Error_msg_1001  = "需要登录"
	Error_code_1002 = 1002
	Error_msg_1002  = "缺失参数"
	Error_code_1003 = 1003
	Error_msg_1003  = "无效参数"
	Error_code_1004 = 1004
	Error_msg_1004  = "没有权限"
	Error_code_1005 = 1005
	Error_msg_1005  = "请求方式有误"
)

var R = &r{}

type M map[string]interface{}
type r struct{}

//校验是否缺少请求参数
func (r *r) CheckReqParam(w http.ResponseWriter, req *http.Request, keys ...string) bool {
	msg := Error_msg_1002
	array := []string{}
	for _, v := range keys {
		if len(req.Form[v]) > 0 {
			continue
		}
		array = append(array, v)
	}
	if len(array) > 0 {
		msg += strings.Join(array, ",")
		log.Println(msg)
		r.ServeJson(w, req, &Result{
			Error_code: Error_code_1002,
			Error_msg:  msg,
		})
		return false
	}
	return true
}

//无效参数
func (r *r) InvalidReqParam(w http.ResponseWriter, req *http.Request, args ...string) string {
	msg := Error_msg_1003 + strings.Join(args, ",")
	r.ServeJson(w, req, &Result{
		Error_code: Error_code_1003,
		Error_msg:  msg,
	})
	log.Println(msg)
	return msg
}

//没有权限
func (r *r) NoPermissionReq(w http.ResponseWriter, req *http.Request, args ...string) string {
	msg := Error_msg_1004
	if len(args) >= 0 {
		msg += "，"
	}
	msg += strings.Join(args, "，")
	r.ServeJson(w, req, &Result{
		Error_code: Error_code_1004,
		Error_msg:  msg,
	})
	log.Println(msg)
	return msg
}

func (r *r) ServeJson(w http.ResponseWriter, req *http.Request, result *Result) {
	content, err := json.MarshalIndent(result, "", "  ")
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}
	w.Header().Set("Content-Length", strconv.Itoa(len(content)))
	w.Header().Set("Content-Type", "application/json")
	w.Write(content)
}

func NewResult(data interface{}, err error) Result {
	errCode := 0
	errMsg := ""
	if err != nil {
		errCode = -1
		errMsg = err.Error()
	}
	return Result{
		Error_code: errCode,
		Error_msg:  errMsg,
		Data:       data,
	}
}

//接口统一返回值
type Result struct {
	Error_code int         `json:"error_code"`
	Error_msg  string      `json:"error_msg"`
	Data       interface{} `json:"data"`
}