package goog

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

	"golang.org/x/oauth2"
)

var (
	ProfileURL    = "https://www.googleapis.com/oauth2/v3/userinfo"
	ProfileKeyFmt = "goog:%s"
)

// GoogleProfile auth'd user profile
// ProfileId, Email, Name, PictureURL
type GoogleProfile struct {
	ProfileID  string `json:"sub"`
	Email      string `json:"email"`
	Name       string `json:"name"`
	PictureURL string `json:"picture"`
}

// ProfileKeys conform to ProfileKeys
func (gp *GoogleProfile) ProfileKeyValues() (string, []string) {
	return fmt.Sprintf(ProfileKeyFmt, gp.Email), []string{
		"profile_id", gp.ProfileID,
		"email", gp.Email,
		"name", gp.Name,
		"picture_url", gp.PictureURL,
	}
}

type Servicer interface {
	Config() *oauth2.Config
	Profile(client *http.Client) (*GoogleProfile, *oauth2.Token, error)
	UserClient(ctx context.Context, token *oauth2.Token) *http.Client
}

// NewService container for interacting with Google
func NewService(o *oauth2.Config) Servicer {
	return &Goog{
		o,
	}

}

type Goog struct {
	oauthConfig *oauth2.Config
}

func (g *Goog) Config() *oauth2.Config {
	return g.oauthConfig
}

// UserCient just calls oauth2.Client
func (g *Goog) UserClient(ctx context.Context, token *oauth2.Token) *http.Client {
	return g.oauthConfig.Client(ctx, token)
}

// Profile get profile from google
func (g *Goog) Profile(client *http.Client) (*GoogleProfile, *oauth2.Token, error) {
	client.Get(ProfileURL)
	resp, err := client.Get(ProfileURL)
	if err != nil {
		return &GoogleProfile{}, &oauth2.Token{}, err
	}
	defer resp.Body.Close()
	data, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return &GoogleProfile{}, &oauth2.Token{}, err
	}
	// Google Profile
	gp := &GoogleProfile{}
	err = json.Unmarshal(data, gp)
	if err != nil {
		return &GoogleProfile{}, &oauth2.Token{}, err
	}
	// Token
	token := &oauth2.Token{}
	err = json.Unmarshal(data, token)
	if err != nil {
		return &GoogleProfile{}, &oauth2.Token{}, err
	}
	return gp, token, nil
}