<?php

namespace App\Services;

use App\Models\AppNotification;
use App\Models\AppNotificationRead;
use Illuminate\Database\Eloquent\Builder;

/**
 * تعداد خوانده‌نشده + پخش SSE رویداد unread-count برای اپ کاربر.
 */
class AppNotificationUnreadService
{
    public function __construct(
        private readonly ConfigService $config,
        private readonly PriceStreamService $stream,
    ) {
    }

    public function featureEnabled(): bool
    {
        return $this->config->getBool('has_page_notification', true);
    }

    public function visibleQuery(int $customerId): Builder
    {
        return AppNotification::query()
            ->where('is_active', true)
            ->where(function (Builder $q) use ($customerId) {
                $q->where('audience_type', AppNotificationAudienceService::TYPE_ALL)
                    ->orWhere(function (Builder $inner) use ($customerId) {
                        $inner->whereIn('audience_type', [
                            AppNotificationAudienceService::TYPE_SEGMENT,
                            AppNotificationAudienceService::TYPE_CUSTOMERS,
                        ])->whereHas('recipients', function (Builder $r) use ($customerId) {
                            $r->where('customer_id', $customerId);
                        });
                    });
            });
    }

    public function countForCustomer(int $customerId): int
    {
        if ($customerId <= 0 || ! $this->featureEnabled()) {
            return 0;
        }

        $visibleIds = $this->visibleQuery($customerId)->select('id');
        $total = (clone $visibleIds)->count();
        $read = AppNotificationRead::query()
            ->where('customer_id', $customerId)
            ->whereIn('notification_id', $visibleIds)
            ->count();

        return max(0, $total - $read);
    }

    /**
     * @return array{unread_count: int}
     */
    public function payloadForCustomer(int $customerId): array
    {
        return [
            'unread_count' => $this->countForCustomer($customerId),
        ];
    }

    public function publishForCustomer(int $customerId): void
    {
        if ($customerId <= 0 || ! $this->featureEnabled() || ! $this->stream->isEnabled()) {
            return;
        }

        $this->stream->publishForCustomer(
            $customerId,
            'unread-count',
            $this->payloadForCustomer($customerId)
        );
    }
}