What potential issues could arise from directly comparing the admin level in the PHP function admin_check()?

Directly comparing the admin level in the PHP function admin_check() may lead to security vulnerabilities as it can be susceptible to manipulation and unauthorized access. To solve this issue, it is recommended to use a more secure method such as role-based access control (RBAC) or access control lists (ACL) to determine the admin level.

// Better approach using RBAC or ACL to check admin level
function admin_check($user_id) {
    // Check if user has the admin role
    if (check_admin_role($user_id)) {
        return true;
    } else {
        return false;
    }
}

function check_admin_role($user_id) {
    // Logic to check if user has admin role
    // This could involve querying a database or checking against a predefined list
    return true; // Return true if user has admin role, false otherwise
}