<?php
/**
 * This source file is part of the open source project
 * ExpressionEngine (https://expressionengine.com)
 *
 * @link      https://expressionengine.com/
 * @copyright Copyright (c) 2003-2022, Packet Tide, LLC (https://www.packettide.com)
 * @license   https://expressionengine.com/license Licensed under Apache License, Version 2.0
 */

/**
 * Core File Integrity
 */
class File_integrity
{
    public $emailed = array();
    public $checksums = array();

    /**
     * Check all bootstrap files
     *
     * @access  public
     */
    public function check_bootstrap_files($return_site_id = false)
    {
        $sites = ee('Model')->get('Site')->fields('site_id', 'site_bootstrap_checksums')->all();

        $bootstraps = array();

        // Retrieve all of the bootstrap files
        foreach ($sites as $site) {
            if (empty($site->site_bootstrap_checksums)) {
                continue;
            }

            $data = $site->site_bootstrap_checksums;

            if (! isset($data['emailed']) or ! is_array($data['emailed'])) {
                $data['emailed'] = array();
            }

            $bootstraps[$site->site_id] = $data;
        }

        $altered = array();
        $removed = array();
        $update_db = array();

        // Check them all
        foreach ($bootstraps as $site_id => $checksums) {
            foreach ($checksums as $path => $checksum) {
                if ($path == 'emailed') {
                    continue;
                }

                if (! file_exists($path)) {
                    $removed[$site_id][] = $path;
                } else {
                    $this->checksums[$site_id][$path] = $checksum;

                    $current = md5_file($path);

                    if ($current != $checksum) {
                        if ($return_site_id) {
                            $altered[$site_id][] = $path;
                        } else {
                            $altered[] = $path;
                        }
                    } elseif (($email_key = array_search($path, $checksums['emailed'])) !== false) {
                        // they were emailed about it and restored it without
                        // hitting the 'accept changes' link on the homepage

                        unset($bootstraps[$site_id]['emailed'][$email_key]);
                        $update_db[] = $site_id;
                    }
                }
            }

            $this->emailed = array_unique(array_merge($this->emailed, $bootstraps[$site_id]['emailed']));
        }

        // Remove obsolete files from the db
        foreach ($removed as $site_id => $paths) {
            foreach ($paths as $path) {
                if (isset($bootstraps[$site_id][$path])) {
                    unset($bootstraps[$site_id][$path]);
                    $update_db[] = $site_id;
                }
            }
        }

        // Update the db if we detected changes
        foreach (array_unique($update_db) as $site_id) {
            $this->_update_config($bootstraps[$site_id], $site_id);
        }

        // Any changes? report them
        if (count($altered)) {
            return $altered;
        }

        return false;
    }

    /**
     * Add a bootstrap file we didn't know about, or explicitly update
     * a checksum (when accepting a change).
     *
     * @access  public
     */
    public function send_site_admin_warning($altered)
    {
        $affected_paths = array_diff($altered, $this->emailed);

        if (count($affected_paths)) {
            ee()->load->library('notifications');
            ee()->notifications->send_checksum_notification($affected_paths);

            // add them to the existing emailed and update
            $affected_paths = array_unique(array_merge($this->emailed, $affected_paths));

            foreach ($this->checksums as $site_id => $checksums) {
                $checksum_paths = array_keys($checksums);

                // did we send emails for this site id?
                $old_emailed = array_intersect($checksum_paths, $this->emailed);
                $new_emailed = array_intersect($checksum_paths, $affected_paths);

                if (count($new_emailed)) {
                    $checksums['emailed'] = array_unique(array_merge($old_emailed, $new_emailed));
                    $this->_update_config($checksums, $site_id);
                }
            }
        }
    }

    /**
     * Add a bootstrap file we didn't know about, or explicitly update
     * a checksum (when accepting a change).
     *
     * @access  public
     */
    public function create_bootstrap_checksum($path = '', $site_id = '')
    {
        $checksums = ee()->config->item('site_bootstrap_checksums');
        $site_id = ($site_id != '') ? $site_id : ee()->config->item('site_id');

        if (REQ == 'CP' && $path && file_exists($path)) {
            $checksums = $this->checksums[$site_id];       // should already have called check_bootstrap_files
            $checksums[$path] = md5_file($path);
            $checksums['emailed'] = array();

            $this->_update_config($checksums, $site_id);
        } elseif (REQ != 'CP' && ! array_key_exists(FCPATH . EESELF, $checksums)) {
            $checksums[FCPATH . EESELF] = md5_file(FCPATH . EESELF);

            $this->_update_config($checksums, $site_id);
        }
    }

    /**
     * Update the bootstrap column in the db
     *
     * @access  private
     */
    public function _update_config($checksums, $site_id)
    {
        if ($site_id == ee()->config->item('site_id')) {
            ee()->config->config['site_bootstrap_checksums'] = $checksums;
        }

        ee()->db->query(ee()->db->update_string(
            'exp_sites',
            array('site_bootstrap_checksums' => base64_encode(serialize($checksums))),
            "site_id = '" . ee()->db->escape_str($site_id) . "'"
        ));
    }
}

// END File_integrity class

// EOF
