<?php
/**
 * Bounded worker. The durable sending marker precedes all outbound mail.
 *
 * @package Abientot
 */

namespace Abientot\Reminders;

use Abientot\Notifications\EmailService;
use Abientot\Repositories\BookingLock;

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

require_once __DIR__ . '/Repository.php';

final class Service {
	private Repository $repository;

	/** @var callable(int,string,string):bool */
	private $sender;

	/** @var callable():int */
	private $clock;

	public function __construct( ?Repository $repository = null, ?callable $sender = null, ?callable $clock = null ) {
		$this->repository = $repository ?? new Repository();
		$this->sender     = $sender ?? static fn( int $id, string $subject, string $body ): bool => ( new EmailService() )->send_custom_booking( $id, $subject, $body, array( 'template' => 'reminder' ) );
		$this->clock      = $clock ?? static fn(): int => time();
	}

	/** Sends at most $limit due reminders; returns how many the mail transport accepted. */
	public function run( int $limit = 10 ): int {
		if ( BookingLock::is_held() ) {
			return 0;
		}
		$now = (int) ( $this->clock )();
		$this->repository->reconcile( $now );
		$sent = 0;
		for ( $i = 0; $i < max( 1, min( 20, $limit ) ); ++$i ) {
			$now = (int) ( $this->clock )();
			$job = $this->repository->claim( $now );
			if ( ! $job ) {
				break;
			}
			$settings = $this->repository->begin_send( $job, $now );
			if ( ! $settings ) {
				continue;
			}
			try {
				if ( ! $this->repository->deliverable( $job, (int) ( $this->clock )() ) ) {
					$this->repository->finish_unsent( $job, (int) ( $this->clock )() );
					continue;
				}
				$result  = ( $this->sender )( (int) $job['appointment_id'], $settings['subject'], $settings['body'] );
				$outcome = $result === true ? 'sent' : 'transport_false';
			} catch ( \Throwable $error ) {
				$outcome = 'transport_exception';
			}
			$this->repository->finish( $job, $outcome, (int) ( $this->clock )() );
			if ( $outcome === 'sent' ) {
				++$sent;
			}
		}
		return $sent;
	}
}