package appimport (	"farga/db/types"	"farga/lib"	o "farga/lib/oauth2"	"fmt"	"net/http"	"time"	"golang.org/x/oauth2")// sends user to hackatime oauth2func (a *App) HackatimeLogin(w http.ResponseWriter, r *http.Request) {	user, ok := r.Context().Value(lib.UserKey).(*types.User)	if !ok {		http.Error(w, "401 Unauthorized.", http.StatusUnauthorized)		return	}	state, err := a.Store.CreateOAuthState(user.ID)	if err != nil {		http.Error(w, "500 Internal Server Error.", http.StatusInternalServerError)		return	}	oAuthConf := o.HackatimeConfig(a.Config)	url := oAuthConf.AuthCodeURL(state.State, oauth2.S256ChallengeOption(state.Verifier))	http.Redirect(w, r, url, http.StatusFound)}func (a *App) HackatimeCallback(w http.ResponseWriter, r *http.Request) {	stateID := r.URL.Query().Get("state")	state, err := a.Store.OAuthState(stateID)	if err != nil {		http.Error(w, "Invalid state.", http.StatusBadRequest)		return	}	user, ok := r.Context().Value(lib.UserKey).(*types.User)	if !ok {		http.Error(w, "401 Unauthorized.", http.StatusUnauthorized)		return	}	if state.UserID != user.ID {		http.Error(w, "403 Forbidden.", http.StatusForbidden)		return	}	a.Store.DeleteOAuthState(state.ID)	if time.Now().After(state.ExpiresAt) {		http.Error(w, "State expired", http.StatusBadRequest)		return	}	code := r.URL.Query().Get("code")	oAuthConf := o.HackatimeConfig(a.Config)	token, err := oAuthConf.Exchange(r.Context(), code, oauth2.VerifierOption(state.Verifier))	if err != nil {		http.Error(w, err.Error(), 500)		return	}	err = a.Store.SaveHackatimeToken(state.UserID, token.AccessToken)	if err != nil {		fmt.Println("BAD ERROR: ", err)		http.Error(w, "Something went wrong on our end.", http.StatusInternalServerError)		return	}	http.Redirect(w, r, "/config?msg=HackatimeLinked", http.StatusSeeOther)}