<?php
declare(strict_types=1);

class OutboundWorker
{
    private const BATCH_SIZE = 10;

    public static function processQueue(): array
    {
        $processed = 0;
        $errors    = [];

        $items = self::dequeue();

        foreach ($items as $item) {
            try {
                $result = self::process($item);

                if ($result['success']) {
                    $stmt = db()->prepare("UPDATE outbound_queue SET status = 'sent', wam_id = ?, updated_at = NOW() WHERE id = ?");
                    $stmt->execute([$result['wam_id'], $item['id']]);
                    $processed++;
                } else {
                    $attempts = (int)$item['attempts'] + 1;
                    $max      = (int)$item['max_attempts'];

                    if ($attempts >= $max) {
                        $stmt = db()->prepare("UPDATE outbound_queue SET status = 'failed', attempts = ?, last_error = ?, updated_at = NOW() WHERE id = ?");
                        $stmt->execute([$attempts, $result['error'], $item['id']]);
                    } else {
                        $stmt = db()->prepare("UPDATE outbound_queue SET status = 'queued', attempts = ?, last_error = ?, updated_at = NOW() WHERE id = ?");
                        $stmt->execute([$attempts, $result['error'], $item['id']]);
                    }

                    $errors[] = "msg#{$item['id']}: {$result['error']}";
                }
            } catch (\Exception $e) {
                $errors[] = "msg#{$item['id']}: " . $e->getMessage();
            }
        }

        return ['processed' => $processed, 'errors' => $errors];
    }

    private static function dequeue(): array
    {
        $db = db();
        $db->beginTransaction();

        try {
            $stmt = $db->prepare("
                SELECT q.*, c.phone_number_id
                FROM outbound_queue q
                JOIN companies c ON c.id = q.company_id
                WHERE q.status = 'queued' AND c.is_active = 1
                ORDER BY q.id ASC
                LIMIT ?
                FOR UPDATE SKIP LOCKED
            ");
            $stmt->execute([self::BATCH_SIZE]);
            $items = $stmt->fetchAll();

            if (!empty($items)) {
                $ids = array_column($items, 'id');
                $placeholders = implode(',', array_fill(0, count($ids), '?'));
                $db->prepare("UPDATE outbound_queue SET status = 'sending', updated_at = NOW() WHERE id IN ({$placeholders})")->execute($ids);
            }

            $db->commit();
            return $items;
        } catch (\Exception $e) {
            $db->rollBack();
            throw $e;
        }
    }

    private static function process(array $item): array
    {
        $payload = json_decode($item['payload'], true);
        if (!is_array($payload)) {
            return ['success' => false, 'error' => 'Payload inválido'];
        }

        $phoneNumberId = $item['phone_number_id'] ?: env('WHATSAPP_DEFAULT_PHONE_NUMBER_ID', '');
        $type          = $item['message_type'];
        $to            = $item['to_number'];

        return match ($type) {
            'text'    => WhatsAppSender::sendText($to, $payload['text'] ?? '', $phoneNumberId),
            'image'   => WhatsAppSender::sendImage($to, $payload['media_id'] ?? $payload['url'] ?? '', $phoneNumberId, $payload['caption'] ?? null),
            'template'=> WhatsAppSender::sendTemplate($to, $payload['template_name'] ?? '', $phoneNumberId, $payload['components'] ?? []),
            'interactive' => WhatsAppSender::sendInteractive($to, $payload['interactive'] ?? [], $phoneNumberId),
            default   => ['success' => false, 'error' => "Tipo no soportado: {$type}"],
        };
    }
}