package handlers

import (
	"encoding/json"
	"fmt"
	"io"
	"net/http"

	"github.com/spf13/viper"
)

var code2Session = "https://api.weixin.qq.com/sns/jscode2session?appid=%s&secret=%s&js_code=%s&grant_type=authorization_code"

type LoginRequest struct {
	Code string `json:"code"`
}

// 封装code2session接口返回数据
type LoginResponse struct {
	OpenId     string `json:"openid"`
	SessionKey string `json:"session_key"`
	UnionId    string `json:"unionid"`
	ErrCode    int    `json:"errcode"`
	ErrMsg     string `json:"errmsg"`
}

func getLoginResponse(code string) (*LoginResponse, error) {
	appid := viper.GetString("wechat.appid")
	secret := viper.GetString("wechat.secret")
	url := fmt.Sprintf(code2Session, appid, secret, code)
	resp, err := http.Get(url)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	var loginResponse LoginResponse
	if err := json.NewDecoder(resp.Body).Decode(&loginResponse); err != nil {
		return nil, err
	}

	if loginResponse.ErrCode != 0 {
		return nil, fmt.Errorf("code2session error: %s", loginResponse.ErrMsg)
	}
	return &loginResponse, nil
}

func (h *Handler) Login(w http.ResponseWriter, r *http.Request) {

	var req LoginRequest
	body, err := io.ReadAll(r.Body)
	if err != nil {
		http.Error(w, "Failed to read request body", http.StatusBadRequest)
		return
	}
	if err := json.Unmarshal(body, &req); err != nil {
		http.Error(w, "Failed to parse request body", http.StatusBadRequest)
		return
	}

	loginResponse, err := getLoginResponse(req.Code)
	if err != nil {
		http.Error(w, "Failed to get session key", http.StatusInternalServerError)
		return
	}

	// // 插入或更新用户的openid和sessionid
	// query := `
	// 	INSERT INTO users (openid, sessionid)
	// 	VALUES ($1, $2)
	// 	ON CONFLICT (openid) DO UPDATE SET sessionid = $2
	// 	RETURNING id;
	// `

	// var ID int
	// if err := h.DB.QueryRow(query, loginResponse.OpenId, loginResponse.SessionKey).Scan(&ID); err != nil {
	// 	http.Error(w, "Failed to log in user", http.StatusInternalServerError)
	// 	return
	// }

	data := map[string]interface{}{
		"openid":      loginResponse.OpenId,
		"session_key": loginResponse.SessionKey,
	}
	respData, err := json.Marshal(data)
	if err != nil {
		http.Error(w, "Failed to marshal response data", http.StatusInternalServerError)
		return
	}
	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(http.StatusOK)
	w.Write([]byte(respData))
}