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

if (!isset($_SESSION['user_id'])) {
    header("location: login.php");
    exit;
}

if ($_SERVER['REQUEST_METHOD'] === 'POST' && isset($_POST['competition_id'])) {
    $user_id = $_SESSION['user_id'];
    $competition_id = $_POST['competition_id'];

    try {
        $pdo = db();
        $stmt = $pdo->prepare("INSERT INTO competition_participants (user_id, competition_id) VALUES (?, ?)");
        $stmt->execute([$user_id, $competition_id]);
    } catch (PDOException $e) {
        // Handle potential errors, like trying to join the same competition twice
        // You might want to log this error or show a message
    }
}

header("location: user_dashboard.php");
exit;