package main

import (
	"bytes"
	"fmt"
	"io/ioutil"
	"net/http"
)

//menu is a json definition
var menu = []byte(`
{
     "button":[
     {	
          "type":"click",
          "name":"今日歌曲",
          "key":"V1001_TODAY_MUSIC"
      },
      {
           "name":"菜单",
           "sub_button":[
           {	
               "type":"view",
               "name":"搜索",
               "url":"http://www.soso.com/"
            },
            {
               "type":"click",
               "name":"赞一下我们",
               "key":"V1001_GOOD"
            }]
       }]
}
`)

//CreateCustomMenu   bulid a menu for wechat windows
//    3 main manu max  (< 4 mandarin words)
//    5 sub items max  (< 7 mandarin words)
//success return nil
//error return err
func CreateCustomMenu(m []byte) error {
	atoken, err := GetAccessToken()
	if err != nil {
		return err
	}
	url := fmt.Sprintf("https://api.weixin.qq.com/cgi-bin/menu/create?access_token=%s", atoken)
	if len(m) == 0 {
		m = menu //using default menu
	}
	return jsonPostRequest(url, m)

}

//CreateDefaultMenu build a menu for wechat window
//
func CreateDefaultMenu() error {
	var b []byte
	return CreateCustomMenu(b)
}

//jsonPostRequest perform http post request with json body
//   url is the url to post to
//   jsonBody is the payload in http post request
func jsonPostRequest(url string, jsonBody []byte) error {
	req, err := http.NewRequest("POST", url, bytes.NewBuffer(jsonBody))
	if err != nil {
		return err
	}
	req.Header.Set("X-Custom-Header", "Patrick Sun")
	req.Header.Set("Content-Type", "application/json")

	client := &http.Client{}
	resp, err := client.Do(req)

	if err != nil {
		return err
	}
	defer resp.Body.Close()

	fmt.Println("response Status:", resp.Status)
	fmt.Println("response Headers:", resp.Header)
	body, _ := ioutil.ReadAll(resp.Body)
	fmt.Println("response Body:", string(body))

	return nil
}