package google

import (
	"bytes"
	"encoding/json"
	"errors"
	"fmt"
	"go-cal/pkg/config"
	"go-cal/pkg/types"
	"io/ioutil"
	"net/http"
	"net/url"
	"time"
)

var baseURL = "https://www.googleapis.com/"

func getURL(p string) (string, error) {
	u, err := url.Parse(baseURL)
	if err != nil {
		return "", err
	}
	u, err = u.Parse(p)
	if err != nil {
		return "", err
	}
	return u.String(), nil
}

func getHeaders() map[string]string {
	obj := make(map[string]string)
	// conf := config.Get()

	return obj
}

// OAuthExchangeCodeToToken -
func OAuthExchangeCodeToToken(code string) (token types.GoogleAuthToken, err error) {
	conf := config.Get()
	if conf == nil {
		return token, errors.New("config not init")
	}

	u, err := url.Parse(conf.Google.TokenURL)
	if err != nil {
		return
	}

	qs := url.Values{}
	qs.Set("code", code)
	qs.Set("client_id", conf.Google.ClientID)
	qs.Set("client_secret", conf.Google.ClientSecret)
	qs.Set("redirect_uri", conf.Google.RedirectURL)
	qs.Set("grant_type", "authorization_code")

	reader := bytes.NewReader([]byte(qs.Encode()))

	req, err := http.NewRequest("POST", fmt.Sprintf("%s", u.String()), reader)
	if err != nil {
		return
	}
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")

	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		return
	}
	defer resp.Body.Close()

	b, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return
	}
	err = json.Unmarshal(b, &token)
	if err != nil {
		return
	}
	return
}

// OAuthRefreshToken -
func OAuthRefreshToken(refreshToken string) (token string, expiresIn int64, err error) {
	if len(refreshToken) == 0 {
		return "", 0, errors.New("refresh token is empty")
	}

	conf := config.Get()
	if conf == nil {
		return "", 0, errors.New("config not init")
	}

	u, err := url.Parse(conf.Google.TokenURL)
	if err != nil {
		return
	}

	qs := url.Values{}
	qs.Set("client_id", conf.Google.ClientID)
	qs.Set("client_secret", conf.Google.ClientSecret)
	qs.Set("grant_type", "refresh_token")

	reader := bytes.NewReader([]byte(qs.Encode()))

	req, err := http.NewRequest("POST", u.String(), reader)
	if err != nil {
		return
	}
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")

	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		return
	}
	defer resp.Body.Close()

	var tokenData types.GoogleAuthToken
	err = json.NewDecoder(resp.Body).Decode(&tokenData)
	if err != nil {
		return
	}
	tokenData.ExpiresIn += time.Now().Unix()

	return tokenData.AccessToken, tokenData.ExpiresIn, nil
}

// GetTokenInfo -
func GetTokenInfo(token string) (expire int64, err error) {
	u, err := url.Parse("https://oauth2.googleapis.com/tokeninfo")
	if err != nil {
		return
	}

	body := struct {
		Azp        string      `json:"azp"`
		Aud        string      `json:"aud"`
		Scope      string      `json:"scope"`
		Exp        json.Number `json:"exp"`
		ExpiresIn  json.Number `json:"expires_in"`
		AccessType string      `json:"access_type"`
	}{}

	qs := url.Values{}
	qs.Set("access_token", token)

	resp, err := http.Get(fmt.Sprintf("%s?%s", u.String(), qs.Encode()))
	if err != nil {
		return
	}
	defer resp.Body.Close()

	err = json.NewDecoder(resp.Body).Decode(&body)
	if err != nil {
		return
	}

	expTime, err := body.Exp.Int64()
	if err != nil {
		return
	}

	return expTime, nil
}