package site

import (
	"context"
	"fmt"
	"net/http"
	"ruben/inventory2/internal/site/response"
	"time"
)

// GET /login
func (s *Server) loginPage(r *http.Request) (response.Response, error) {
	ctx := r.Context()

	u, err := s.newLoginURL(ctx, "/")
	if err != nil {
		return nil, err
	}

	return response.TemporaryRedirect(u), nil
}

func (s *Server) newLoginURL(ctx context.Context, targetURI string) (string, error) {
	state, err := s.auth.NewState(ctx, targetURI)
	if err != nil {
		return "", fmt.Errorf("failed to generate random state: %w", err)
	}

	base64EncodedState := fmt.Sprintf("%x", state[:])

	return s.auth.AuthCodeURL(base64EncodedState), nil
}

// POST /login
func (s *Server) login(r *http.Request) (response.Response, error) {
	ctx := r.Context()
	email := r.FormValue("email")
	if email == "" {
		return nil, response.BadRequest().Msg("no email provided")
	}

	acct, err := s.accts.GetAccountByEmail(ctx, email)
	if err != nil {
		return nil, response.Errorf("failed to create account: %w", err)
	}

	return response.SeeOther(fmt.Sprintf("/accounts/%d", acct.AccountID)), nil
}

// GET /login/callback
func (s *Server) loginCallback(r *http.Request) (response.Response, error) {
	ctx := r.Context()
	q := r.URL.Query()

	// obtain token and profile

	accessToken, targetURI, expiration, err := s.auth.Exchange(ctx, q.Get("state"), q.Get("code"))
	if err != nil {
		return nil, response.Unauthorized().
			Msg(fmt.Sprintf("Failed to exchange an authorization code for a token")).
			Wrap(err)
	}

	// set access_token cookie and redirect to a reasonable place

	return response.TemporaryRedirect(targetURI).
		Cookie(newAccessTokenCookie(accessToken, expiration)), nil
}

func newAccessTokenCookie(tkn string, expiration time.Time) http.Cookie {
	return http.Cookie{
		Name:    "access_token",
		Value:   tkn,
		Path:    "/",
		Expires: expiration,
		MaxAge:  0, // using Expiration instead
		Secure:  true,
	}
}

// GET /logout
func (s *Server) logoutPage(r *http.Request) (response.Response, error) {
	host := r.Header.Get("X-Forwarded-Host")
	if host == "" {
		host = r.Host
	}

	if ck, err := r.Cookie("access_token"); err == nil && ck != nil {
		if err := s.auth.DeleteOAuthTokens(r.Context(), ck.Value); err != nil {
			fmt.Println("[ERROR] failed to delete auth token:", err)
		}
	}

	return response.TemporaryRedirect(s.auth.GetLogoutURL(host).String()).
		Cookie(getExpiredCookie("access_token")), nil
}