<?php
namespace App\Services;
use App\Models\Articles;
use App\Services\Editorial\IndexNowNotification;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Schema;
final class SeoNotifications
{
    public function changed(Articles $a, bool $deleted = false): void
    {
        if (!Schema::hasTable('seo_notifications')) return;
        $urls = [];
        if ($deleted || !Seo::public($a)) $urls[] = Seo::articleUrl($a);
        elseif (Seo::indexable($a)) $urls[] = Seo::articleUrl($a);
        if ($a->oCategory?->sSlug === 'freenode') $urls[] = Seo::url();
        if ($a->oCategory) $urls[] = Seo::url(Seo::categoryPath($a->oCategory));
        $event = $deleted || !Seo::public($a) ? 'delete' : 'update';
        $key = hash('sha256',json_encode([$a->id,$event,$a->sContentUpdatedAt,$a->sTitle,$a->sContent,$a->sThumb,$a->iStatus]));
        $this->enqueue($key,$urls,$event);
    }
    public function enqueue(string $key, array $urls, string $event = 'update'): void
    {
        if (!app()->environment(['production','testing']) || !config('editorial.indexnow_enabled',app()->environment('production'))) return;
        DB::table('seo_notifications')->insertOrIgnore(['event_key'=>$key,'urls'=>json_encode(array_values(array_unique($urls))),
            'event'=>$event,'state'=>json_encode(['status'=>'pending','attempts'=>0]),'created_at'=>now(),'updated_at'=>now()]);
    }
    public function retry(int $limit = 10): int
    {
        $processed = 0;
        foreach (DB::table('seo_notifications')->orderBy('id')->cursor() as $candidate) {
            $s = json_decode($candidate->state,true);
            if (($s['status'] ?? '') !== 'pending' || ($s['next_attempt_at'] ?? 0) > now()->timestamp) continue;
            DB::transaction(function () use ($candidate,&$processed) {
                $row = DB::table('seo_notifications')->where('id',$candidate->id)->lockForUpdate()->first();
                $state = json_decode($row->state,true);
                if (($state['status'] ?? '') !== 'pending' || ($state['next_attempt_at'] ?? 0) > now()->timestamp) return;
                $urls = json_decode($row->urls,true);
                if ($row->event !== 'delete') $urls = array_values(array_filter($urls,function($url) {
                    $path = parse_url($url,PHP_URL_PATH);
                    if (preg_match('~^/a/([a-zA-Z0-9_-]+)\.html$~',$path,$m)) {
                        $a = Articles::where('sSlug',$m[1])->first(); return $a && Seo::indexable($a);
                    }
                    if ($path === '/') return app(ArticlesService::class)->getLatestFreeNodeSlug() !== null;
                    return true;
                }));
                $state = app(IndexNowNotification::class)->submit($state,$urls);
                DB::table('seo_notifications')->where('id',$row->id)->update(['state'=>json_encode($state),'updated_at'=>now()]);
                $processed++;
            });
            if ($processed >= $limit) break;
        }
        return $processed;
    }
}