<?php
/**
 * Backup Manager Class
 *
 * All queries here target the plugin's own wpmigpro_backups table, whose rows
 * change constantly while a backup runs, so results are not cached.
 *
 * phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching
 */

if (!defined('ABSPATH')) {
    exit;
}

class WPMigPro_Backup_Manager {

    private function table() {
        global $wpdb;
        return $wpdb->prefix . 'wpmigpro_backups';
    }

    /**
     * Get backups, newest first.
     */
    public function get_backups($limit = 50, $offset = 0) {
        global $wpdb;

        return $wpdb->get_results($wpdb->prepare(
            'SELECT * FROM %i ORDER BY created_at DESC, id DESC LIMIT %d OFFSET %d',
            $this->table(),
            $limit,
            $offset
        ));
    }

    /**
     * Get backup by ID
     */
    public function get_backup($backup_id) {
        global $wpdb;

        return $wpdb->get_row($wpdb->prepare('SELECT * FROM %i WHERE id = %d', $this->table(), $backup_id));
    }

    /**
     * Delete a backup file and its record.
     */
    public function delete_backup($backup_id) {
        global $wpdb;

        $backup = $this->get_backup($backup_id);
        if (!$backup) {
            return array('success' => false, 'message' => __('Backup not found', 'enmigrate-pro'));
        }

        if ($backup->file_path && $this->is_inside_backups_dir($backup->file_path)) {
            WPMigPro_FS::delete($backup->file_path);
        }

        $wpdb->delete($this->table(), array('id' => $backup_id), array('%d'));
        $wpdb->delete($wpdb->prefix . 'wpmigpro_logs', array('backup_id' => $backup_id), array('%d'));

        WPMigPro_Logger::log('Backup deleted: ' . $backup->backup_name);

        return array('success' => true, 'message' => __('Backup deleted successfully', 'enmigrate-pro'));
    }

    /**
     * Only files in our backups folder may be read or deleted through backup records.
     */
    public function is_inside_backups_dir($path) {
        $real = realpath($path);
        $base = realpath(WPMIGPRO_BACKUPS_DIR);
        return $real && $base && strpos(wp_normalize_path($real), trailingslashit(wp_normalize_path($base))) === 0;
    }

    /**
     * Total size of all backup files.
     */
    public function get_total_backup_size() {
        $total_size = 0;
        foreach ($this->get_backups(1000) as $backup) {
            if ($backup->file_path && is_file($backup->file_path)) {
                $total_size += filesize($backup->file_path);
            }
        }
        return $total_size;
    }

    /**
     * Numbers shown on the dashboard.
     */
    public function get_statistics() {
        global $wpdb;
        $table = $this->table();

        return array(
            'total_backups' => (int) $wpdb->get_var($wpdb->prepare('SELECT COUNT(*) FROM %i', $table)),
            'completed_backups' => (int) $wpdb->get_var($wpdb->prepare('SELECT COUNT(*) FROM %i WHERE status = %s', $table, 'completed')),
            'failed_backups' => (int) $wpdb->get_var($wpdb->prepare('SELECT COUNT(*) FROM %i WHERE status = %s', $table, 'failed')),
            'last_backup' => $wpdb->get_var($wpdb->prepare('SELECT MAX(created_at) FROM %i WHERE status = %s AND backup_type <> %s', $table, 'completed', 'imported')),
            'total_size' => $this->get_total_backup_size(),
        );
    }

    /**
     * Keep only the newest N backups created on this site (uploaded files are not touched).
     */
    public function cleanup_old_backups($keep_count) {
        global $wpdb;

        $keep_count = max(1, (int) $keep_count);
        $old = $wpdb->get_col($wpdb->prepare(
            'SELECT id FROM %i WHERE backup_type <> %s AND status = %s ORDER BY created_at DESC, id DESC LIMIT 1000 OFFSET %d',
            $this->table(),
            'imported',
            'completed',
            $keep_count
        ));

        foreach ($old as $id) {
            $this->delete_backup((int) $id);
        }
    }
}