<?php

declare(strict_types=1);

namespace App\Mail;

use App\Support\MailConfig;
use PHPMailer\PHPMailer\Exception as PhpMailerException;
use PHPMailer\PHPMailer\PHPMailer;

/**
 * Sends via SMTP when MAIL_TRANSPORT=smtp, otherwise via PHP's mail() function.
 */
final class PhpMailerMailer implements Mailer
{
    public function __construct(private readonly MailConfig $config)
    {
    }

    public function send(string $to, string $subject, string $body): void
    {
        $mail = new PHPMailer(true);

        try {
            if ($this->config->transport === 'smtp') {
                $this->configureSmtp($mail);
            } else {
                $mail->isMail();
            }

            $mail->setFrom($this->config->fromAddress, $this->config->fromName);
            $mail->addAddress($to);
            $mail->Subject = $subject;
            $mail->isHTML(false);
            $mail->Body = $body;

            $mail->send();
        } catch (PhpMailerException $e) {
            throw new MailException('Failed to send email: ' . $e->getMessage(), 0, $e);
        }
    }

    private function configureSmtp(PHPMailer $mail): void
    {
        $mail->isSMTP();
        $mail->Host = (string) $this->config->smtpHost;
        $mail->Port = $this->config->smtpPort;

        if ($this->config->smtpUsername !== null) {
            $mail->SMTPAuth = true;
            $mail->Username = $this->config->smtpUsername;
            $mail->Password = (string) $this->config->smtpPassword;
        }

        switch ($this->config->smtpEncryption) {
            case 'ssl':
                $mail->SMTPSecure = PHPMailer::ENCRYPTION_SMTPS;
                break;
            case 'none':
                $mail->SMTPSecure = '';
                $mail->SMTPAutoTLS = false;
                break;
            default:
                $mail->SMTPSecure = PHPMailer::ENCRYPTION_STARTTLS;
        }
    }
}