<?php
/**
 * GET /auth/login?return_to=/path[&prompt=none]
 * Sends the browser to auth.sassly.ai. With a live Sassly session there is no login screen (SSO).
 */

declare(strict_types=1);

require __DIR__ . '/../../bootstrap.php'; // ADAPT: the app bootstrap (loads config + DB, includes lib/sassly-auth/sassly_auth_bootstrap.php)

sassly_session_start();
$auth = sassly_auth();
$returnTo = SasslyAuthClient::sanitizeReturnTo($_GET['return_to'] ?? '/', sassly_paths()['home']);
$silent = ($_GET['prompt'] ?? '') === 'none';

// Already logged in here: skip the round trip.
if (!$silent && $auth->check() === SasslyAuthClient::VALID && isset($_SESSION['sassly_user_id'])) {
    header('Location: ' . $returnTo, true, 302);
    exit;
}

$auth->redirectToLogin($returnTo, $silent ? ['prompt' => 'none'] : []);