<?php
session_start();
require_once 'db/config.php';

// Fetch Google Client ID from settings
try {
    $pdo = db();
    $stmt = $pdo->query("SELECT setting_value FROM settings WHERE setting_key = 'google_client_id'");
    $google_client_id = $stmt->fetchColumn();
} catch (PDOException $e) {
    die('Database error fetching Google Client ID. Please configure it in the settings.');
}

if (empty($google_client_id)) {
    die('Google Client ID is not configured. Please ask an administrator to set it up.');
}

$redirect_uri = (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] === 'on' ? "https" : "http") . "://" . $_SERVER['HTTP_HOST'] . dirname($_SERVER['PHP_SELF']) . '/google-callback.php';

$auth_url = 'https://accounts.google.com/o/oauth2/v2/auth?' . http_build_query([
    'client_id' => $google_client_id,
    'redirect_uri' => $redirect_uri,
    'response_type' => 'code',
    'scope' => 'https://www.googleapis.com/auth/userinfo.email https://www.googleapis.com/auth/userinfo.profile',
    'access_type' => 'offline',
    'prompt' => 'select_account'
]);

header('Location: ' . $auth_url);
exit;