<?php
declare(strict_types=1);
if (!defined('ABSPATH')) { exit; }

/** Local-only recheck scheduler. It never applies a fix or calls a provider. */
final class TheDotDevAgenticBridge_Local_Rechecks
{
    public const HOOK = 'thedotdev_agentic_bridge_local_recheck';
    public const WEEKLY = 'thedotdev_agentic_bridge_weekly';
    public const MAX_SNAPSHOTS = 10;
    public const FREQUENCIES = ['daily' => 'Daily', self::WEEKLY => 'Weekly'];

    public static function register(): void { add_action(self::HOOK, [self::class, 'run_scheduled']); add_filter('cron_schedules', [self::class, 'cron_schedules']); }
    public static function cron_schedules(array $schedules): array { $schedules[self::WEEKLY] = ['interval' => WEEK_IN_SECONDS, 'display' => __('Once weekly', 'agentic-bridge')]; return $schedules; }
    public static function settings(): array { $v = TheDotDevAgenticBridge_Storage::get()['local_rechecks'] ?? []; return is_array($v) ? $v : []; }
    public static function configure(bool $enabled, string $frequency): void
    {
        $frequency = array_key_exists($frequency, self::FREQUENCIES) ? $frequency : self::WEEKLY;
        $prior = self::settings();
        if (function_exists('wp_clear_scheduled_hook')) wp_clear_scheduled_hook(self::HOOK);
        $next = 0;
        if ($enabled && function_exists('wp_schedule_event')) {
            $next = time() + HOUR_IN_SECONDS;
            $scheduled = wp_schedule_event($next, $frequency, self::HOOK);
            if ($scheduled === false) {
                TheDotDevAgenticBridge_Storage::update(['local_rechecks' => array_merge($prior, [
                    'enabled' => false, 'frequency' => $frequency, 'nextRun' => 0,
                    'lastError' => 'schedule_failed', 'lastOutcome' => 'failed',
                    'lastFailureAt' => TheDotDevAgenticBridge_Readiness_Clock::iso(),
                ])]);
                return;
            }
        }
        TheDotDevAgenticBridge_Storage::update(['local_rechecks' => array_merge($prior, ['enabled' => $enabled, 'frequency' => $frequency, 'nextRun' => $next, 'lastRun' => (string) ($prior['lastRun'] ?? ''), 'lastError' => ''])]);
    }
    public static function run_scheduled(): void { self::run('scheduled_local'); }
    public static function run(string $source = 'manual_local'): void
    {
        $settings = self::settings(); $now = time(); if (!empty($settings['lockUntil']) && (int) $settings['lockUntil'] > $now) return;
        $settings['lockUntil'] = $now + 300; $settings['lockOwner'] = $source; TheDotDevAgenticBridge_Storage::update(['local_rechecks' => $settings]);
        try {
            $before = TheDotDevAgenticBridge_Readiness_Store::latest();
            $scanner = new TheDotDevAgenticBridge_Readiness_Scanner();
            $after = apply_filters('thedotdev_agentic_bridge_local_recheck_result', $scanner->run_all(), $source);
            if (!is_array($after)) {
                throw new UnexpectedValueException('Local recheck result was not an array.');
            }
            $after['recheckSource'] = $source;
            $after['drift'] = self::classify($before, $after);
            TheDotDevAgenticBridge_Readiness_Store::save_result($after);
            $settings['lastRun'] = TheDotDevAgenticBridge_Readiness_Clock::iso();
            $settings['lastError'] = '';
            $settings['lastOutcome'] = 'completed';
            $settings['lastSnapshot'] = self::snapshot($after, $source);
            $history = is_array($settings['snapshots'] ?? null) ? $settings['snapshots'] : [];
            array_unshift($history, $settings['lastSnapshot']);
            $settings['snapshots'] = array_slice($history, 0, self::MAX_SNAPSHOTS);
        } catch (Throwable $e) {
            $settings['lastError'] = 'local_recheck_failed';
            $settings['lastOutcome'] = 'failed';
            $settings['lastFailureAt'] = TheDotDevAgenticBridge_Readiness_Clock::iso();
        }
        $settings['lockUntil'] = 0; $settings['lockOwner'] = ''; $settings['nextRun'] = function_exists('wp_next_scheduled') ? (int) wp_next_scheduled(self::HOOK) : 0; TheDotDevAgenticBridge_Storage::update(['local_rechecks' => $settings]);
    }
    public static function deactivate(): void { if (function_exists('wp_clear_scheduled_hook')) wp_clear_scheduled_hook(self::HOOK); }
    /** @return array<string, mixed> */
    private static function snapshot(array $after, string $source): array
    {
        return [
            'at' => TheDotDevAgenticBridge_Readiness_Clock::iso(),
            'source' => $source,
            'scope' => 'this_wordpress_site',
            'freshness' => (string) ($after['scannedAt'] ?? ''),
            'exclusions' => [],
            'score' => $after['score'] ?? null,
            'findings' => is_array($after['findings'] ?? null) ? $after['findings'] : [],
            'drift' => is_array($after['drift'] ?? null) ? $after['drift'] : self::empty_drift(),
        ];
    }

    /** @return array{new:list<string>, changed:list<string>, resolved:list<string>, unchanged:list<string>} */
    private static function empty_drift(): array { return ['new' => [], 'changed' => [], 'resolved' => [], 'unchanged' => []]; }

    /** @return array{new:list<string>, changed:list<string>, resolved:list<string>, unchanged:list<string>} */
    private static function classify(?array $before, array $after): array { $old=[]; foreach (($before['findings'] ?? []) as $f) if(is_array($f)) $old[(string)($f['id']??'')] = (string)($f['status']??''); $new=[]; foreach (($after['findings'] ?? []) as $f) if(is_array($f)) $new[(string)($f['id']??'')] = (string)($f['status']??''); $out=self::empty_drift(); foreach($new as $id=>$s) { if(!isset($old[$id])) $out['new'][]=$id; elseif($old[$id]!==$s) $out['changed'][]=$id; else $out['unchanged'][]=$id; } foreach($old as $id=>$s) if(!isset($new[$id])) $out['resolved'][]=$id; return $out; }
}