<?php

namespace App\Services;

use PHPMailer\PHPMailer\Exception as MailException;
use PHPMailer\PHPMailer\PHPMailer;

class MailService
{
    /**
     * @param string|array<int|string, string|array{address:string,name?:string}> $to
     * @param array<int|string, string|array{address:string,name?:string}> $cc
     * @param array<int|string, string|array{address:string,name?:string}> $bcc
     */
    public function send($to, string $subject, string $htmlBody, ?string $textBody = null, array $cc = [], array $bcc = []): void
    {
        $config = config('mail');
        $mailer = new PHPMailer(true);

        $mailer->CharSet = 'UTF-8';
        $mailer->isHTML(true);

        $driver = strtolower((string)($config['driver'] ?? 'smtp'));

        if ($driver === 'sendmail') {
            $mailer->isSendmail();
            if (!empty($config['sendmail_path'])) {
                $mailer->Sendmail = $config['sendmail_path'];
            }
        } elseif ($driver === 'mail') {
            $mailer->isMail();
        } else {
            $mailer->isSMTP();
            $mailer->Host = (string)($config['host'] ?? 'localhost');
            $mailer->Port = (int)($config['port'] ?? 25);
            $mailer->Timeout = (int)($config['timeout'] ?? 30);

            $username = $config['username'] ?? null;
            $password = $config['password'] ?? null;
            if ($username) {
                $mailer->SMTPAuth = true;
                $mailer->Username = $username;
                $mailer->Password = (string)$password;
            } else {
                $mailer->SMTPAuth = false;
            }

            $encryption = strtolower((string)($config['encryption'] ?? ''));
            if ($encryption === 'ssl') {
                $mailer->SMTPSecure = PHPMailer::ENCRYPTION_SMTPS;
            } elseif ($encryption === 'tls') {
                $mailer->SMTPSecure = PHPMailer::ENCRYPTION_STARTTLS;
            }
        }

        $fromAddress = $config['from']['address'] ?? null;
        $fromName = $config['from']['name'] ?? '';
        if ($fromAddress) {
            $mailer->setFrom($fromAddress, $fromName ?: $fromAddress);
        }

        foreach ($this->normalizeRecipients($to) as $recipient) {
            $mailer->addAddress($recipient['address'], $recipient['name']);
        }

        foreach ($this->normalizeRecipients($cc) as $recipient) {
            $mailer->addCC($recipient['address'], $recipient['name']);
        }

        foreach ($this->normalizeRecipients($bcc) as $recipient) {
            $mailer->addBCC($recipient['address'], $recipient['name']);
        }

        $mailer->Subject = $subject;
        $mailer->Body = $htmlBody;
        $mailer->AltBody = $textBody ?? strip_tags($htmlBody);

        try {
            $mailer->send();
        } catch (MailException $exception) {
            throw new \RuntimeException('Unable to send mail: ' . $exception->getMessage(), previous: $exception);
        }
    }

    /**
     * @param string|array<int|string, string|array{address:string,name?:string}> $addresses
     * @return list<array{address:string,name:string}>
     */
    private function normalizeRecipients($addresses): array
    {
        if ($addresses === null) {
            return [];
        }

        if (!is_array($addresses)) {
            return [['address' => (string)$addresses, 'name' => '']];
        }

        $normalized = [];
        foreach ($addresses as $key => $value) {
            if (is_array($value)) {
                $address = $value['address'] ?? null;
                if (!$address) {
                    continue;
                }
                $normalized[] = [
                    'address' => (string)$address,
                    'name' => (string)($value['name'] ?? ''),
                ];
            } elseif (is_string($key) && is_string($value)) {
                $normalized[] = [
                    'address' => $key,
                    'name' => $value,
                ];
            } else {
                $normalized[] = [
                    'address' => (string)$value,
                    'name' => '',
                ];
            }
        }

        return $normalized;
    }
}