<?php

declare(strict_types=1);

// src/Utils/Mailer/MailerService.php

namespace RprtCli\Utils\Mailer;

use Exception;
use RprtCli\Utils\Configuration\ConfigurationInterface;
use RprtCli\Utils\PdfExport\PdfExportInterface;
use Symfony\Component\Mailer\Mailer;
use Symfony\Component\Mailer\Transport;
use Symfony\Component\Mime\Email;

use function date;
use function explode;
use function fgets;
use function file_exists;
use function rawurlencode;
use function readline;
use function strtotime;
use function system;
use function trim;
use function var_dump;

use const STDIN;

/**
 * Send emails with invoices as attachments.
 *
 * https://symfony.com/doc/current/mailer.html
 */
class MailerService implements MailerInterface
{
    protected $config;

    protected $pdf;

    // Data properties.
    protected $to;
    protected $subject;
    protected $text;
    protected $attachment;
    protected $templatePath;

    protected $email;

    public function __construct(ConfigurationInterface $config, PdfExportInterface $pdf)
    {
        $this->config = $config;
        $this->pdf    = $pdf;
    }

    public function setRecipients(array $to): void
    {
        $this->to = $to;
    }

    public function setSubject(string $subject): void
    {
        $this->subject = $subject;
    }

    public function setAttachment(string $path): void
    {
        // @TODO - add some error handling.
        $this->attachment = $path;
    }

    public function getProperty(string $property)
    {
        // Only for simple value properies - string and numbers.
        // from, to, subject.
        if (! isset($this->{$property})) {
            $value = $this->config->get('email.' . $property, false);
            if (! $value) {
                $value = readline("Property {$property} is not configured. Enter value: ");
            }
            $this->{$property} = $value;
        }
        return $this->{$property};
    }

    protected function getRecipients()
    {
        if (! isset($this->to)) {
            $value = $this->config->get('email.to', false);
            if (! $value) {
                $value = explode(',', readline('Provide recipients\' emails separated by a comma: '));
            }
            $this->to = $value;
        }
        return $this->to;
    }

    private function readPassword($prompt = "Enter Password:")
    {
        echo $prompt;
        system('stty -echo');
        $password = trim(fgets(STDIN));
        system('stty echo');
        return $password;
    }

    protected function getPasswordProperty()
    {
        if (! isset($this->password)) {
            $value = $this->config->get('email.password', false);
            if (! $value) {
                $value = $this->readPassword();
            }
            $this->password = $value;
        }
        return $this->password;
    }

    public function sendMail(string $from, array $to, string $subject, string $text, array $attachment = []): void
    {
        $email = new Email();
        $email->from($from);
        $email->to(...$to);
        // @TODO use twig for templates. Create new template service.
        // https://github.com/symfony/mailer
        $email->subject($subject);
        $email->text($text);
        if (! empty($attachment)) {
            if (! isset($attachment['path'])) {
                var_dump('Attachment path missing!');
            } else {
                $email->attachFromPath($attachment['path'], $attachment['name'] ?? null, $attachment['type'] ?? null);
            }
        }
        // Not sure whether it would be nicer to use class property instead of variable.
        $transport = $this->getTransport();
        $mailer    = $this->getMailer($transport);
        $mailer->send($email);
    }

    public function getTransport()
    {
        // @TODO remove username and password from config.
        $username = rawurlencode($this->getProperty('username'));
        $password = rawurlencode($this->getPasswordProperty());
        // If your credentials contain special characters, you must URL-encode them.
        // $mailer_dsn = "gmail+smtp://{$username}:{$password}@default";
        $mailer_dsn = "gmail://{$username}:{$password}@localhost?encryption=tls&auth_mode=oauth";
        return Transport::fromDsn($mailer_dsn);
    }

    public function getMailer($transport)
    {
        return new Mailer($transport);
    }

    public function sendDefaultMail(string $output): void
    {
        $tokens = $this->pdf->gatherTokensForTemplate(
            $this->getEmailTemplatePath(),
            false,
            $this->getDefaultTokens(),
            'email.tokens'
        );
        $text   = $this->pdf->replaceTokensInTemplate($this->getEmailTemplatePath(), $tokens);
        $this->sendMail(
            $this->getProperty('from'),
            $this->getProperty('to'),
            $this->getProperty('subject'),
            $text,
            ['path' => $output, 'Invoice', 'application/pdf']
        );
    }

    public function getDefaultTokens(): array
    {
        $tokens          = [];
        $date            = strtotime('-1 month');
        $tokens['month'] = date('F', $date);
        $tokens['year']  = date('Y', $date);
        return $tokens;
    }

    protected function getEmailTemplatePath(): ?string
    {
        if (! isset($this->templatePath)) {
            $template_path = $this->config->get('email.template_path', false);
            if (! $template_path) {
                $template_path = readline('Enter template file path: ');
            }
            if (! file_exists($template_path)) {
                throw new Exception('Template file not found!');
            }
            $this->templatePath = $template_path;
        }
        return $this->templatePath;
    }

    public function setEmailTemplatePath(string $path): void
    {
        if (file_exists($path)) {
            $this->templatePath = $path;
            return;
        }
        throw new Exception('Email template file not found!');
    }
}