<?php
if (!defined('ABSPATH')) exit;

return new class extends WPH_Step {
    public function id(): string { return 'database'; }
    public function title(): string { return 'Step 9 — Database'; }
    public function sub_items(): array {
        return [
            'Run a database optimisation (via WP-CLI: wp db optimize, or via a plugin such as WP-Optimize)',
            'Check for and remove any spam comments if comment moderation hasn\'t been keeping up',
            'Check post revisions — if excessive (thousands), note for client discussion on whether a revision limit should be set',
        ];
    }

    public function autocheck(array $session_state): array {
        /** @var wpdb $wpdb */
        global $wpdb;
        $f = [];

        // Spam comments
        $counts = wp_count_comments();
        $f[] = $this->finding(
            'spam_comments',
            ($counts->spam ?? 0) > 100 ? 'warn' : 'ok',
            'Spam comments',
            number_format((int) ($counts->spam ?? 0)),
            ($counts->trash ?? 0) ? number_format((int) $counts->trash) . ' in trash too.' : ''
        );

        // Post revisions
        $revisions = (int) $wpdb->get_var("SELECT COUNT(*) FROM {$wpdb->posts} WHERE post_type = 'revision'");
        $level = $revisions > 5000 ? 'warn' : 'ok';
        $f[] = $this->finding(
            'revisions',
            $level,
            'Post revisions',
            number_format($revisions),
            $level === 'warn' ? 'Consider setting WP_POST_REVISIONS to a sane limit (e.g. 10).' : ''
        );

        // Autoload option size. WP 6.6+ uses 'on'/'auto'/'auto-on' alongside legacy 'yes'.
        $autoload_in = "autoload IN ('yes', 'on', 'auto', 'auto-on')";
        $autoload_bytes = (int) $wpdb->get_var("SELECT SUM(LENGTH(option_value)) FROM {$wpdb->options} WHERE $autoload_in");
        $autoload_count = (int) $wpdb->get_var("SELECT COUNT(*) FROM {$wpdb->options} WHERE $autoload_in");
        $autoload_level = $autoload_bytes > 5 * MB_IN_BYTES ? 'warn' : 'ok';
        $f[] = $this->finding(
            'autoload',
            $autoload_level,
            'Autoload options',
            $autoload_count . ' rows · ' . size_format($autoload_bytes),
            $autoload_level === 'warn' ? 'Large autoload payload slows every request — investigate which plugins are responsible.' : ''
        );

        // Top 3 largest tables. `rows` is reserved in MySQL 8 — alias as table_rows.
        $tables = $wpdb->get_results("
            SELECT TABLE_NAME AS name,
                   DATA_LENGTH + INDEX_LENGTH AS bytes,
                   TABLE_ROWS AS table_rows
            FROM information_schema.TABLES
            WHERE TABLE_SCHEMA = DATABASE()
            ORDER BY bytes DESC
            LIMIT 3
        ");
        foreach ($tables as $i => $t) {
            $f[] = $this->finding(
                'big_table_' . $i,
                'info',
                ($i === 0 ? 'Largest tables — ' : '') . $t->name,
                size_format((int) $t->bytes),
                number_format((int) $t->table_rows) . ' rows'
            );
        }

        return $f;
    }
};