<?php
header('Content-Type: application/json; charset=utf-8');

require_once __DIR__ . '/config.php';

// Vain POST sallittu
if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    http_response_code(405);
    echo json_encode(['success' => false, 'message' => 'Method not allowed']);
    exit;
}

// Lomakkeen tiedot
$name = trim($_POST['name'] ?? '');
$email = trim($_POST['email'] ?? '');
$package = trim($_POST['package'] ?? '');
$message = trim($_POST['message'] ?? '');

// Validointi
if (empty($name) || empty($email) || empty($message)) {
    http_response_code(400);
    echo json_encode(['success' => false, 'message' => 'Täytä kaikki pakolliset kentät.']);
    exit;
}

if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
    http_response_code(400);
    echo json_encode(['success' => false, 'message' => 'Virheellinen sähköpostiosoite.']);
    exit;
}

// Suojaa header injectionilta
$name = str_replace(["\r", "\n"], '', $name);
$email = str_replace(["\r", "\n"], '', $email);

// Sähköpostin aihe
$subject = 'StorageBox.fi - Yhteydenotto: ' . $name;

// Viestin sisältö
$body = "Uusi yhteydenotto StorageBox.fi:n kautta\r\n";
$body .= "========================================\r\n\r\n";
$body .= "Nimi: {$name}\r\n";
$body .= "Sähköposti: {$email}\r\n";
if (!empty($package)) {
    $packages = [
        'mini' => 'Mini — 100 GB — 29€/v',
        'perus' => 'Perus — 200 GB — 69€/v',
        'plus' => 'Plus — 500 GB — 119€/v',
        'pro' => 'Pro — 1 TB — 199€/v',
        'business' => 'Business — 2 TB — 299€/v',
    ];
    $packageName = $packages[$package] ?? $package;
    $body .= "Paketti: {$packageName}\r\n";
}
$body .= "\r\nViesti:\r\n{$message}\r\n";

// Lähetä SMTP:llä
$result = sendSmtp(MAIL_TO, $subject, $body, $email, $name);

if ($result === true) {
    echo json_encode(['success' => true, 'message' => 'Viesti lähetetty! Palaamme asiaan pian.']);
} else {
    http_response_code(500);
    echo json_encode(['success' => false, 'message' => 'Viestin lähetys epäonnistui: ' . $result]);
}

/**
 * Lähettää sähköpostin SMTP:llä (STARTTLS, AUTH LOGIN)
 */
function sendSmtp($to, $subject, $body, $replyToEmail, $replyToName) {
    $host = SMTP_HOST;
    $port = SMTP_PORT;
    $user = SMTP_USER;
    $pass = SMTP_PASS;
    $from = MAIL_FROM;
    $fromName = MAIL_FROM_NAME;

    // Yhdistä SMTP-palvelimeen
    $socket = @fsockopen($host, $port, $errno, $errstr, 10);
    if (!$socket) {
        return "Yhteys epäonnistui: {$errstr} ({$errno})";
    }

    // Lue tervehdys
    $response = smtpRead($socket);
    if (substr($response, 0, 3) !== '220') {
        fclose($socket);
        return "SMTP tervehdys epäonnistui: {$response}";
    }

    // EHLO
    smtpWrite($socket, "EHLO storagebox.fi\r\n");
    $response = smtpRead($socket);

    // STARTTLS
    smtpWrite($socket, "STARTTLS\r\n");
    $response = smtpRead($socket);
    if (substr($response, 0, 3) !== '220') {
        fclose($socket);
        return "STARTTLS epäonnistui: {$response}";
    }

    // Käynnistä TLS
    $crypto = stream_socket_enable_crypto($socket, true, STREAM_CRYPTO_METHOD_TLSv1_2_CLIENT);
    if (!$crypto) {
        fclose($socket);
        return "TLS-salaus epäonnistui";
    }

    // EHLO uudelleen TLS:n jälkeen
    smtpWrite($socket, "EHLO storagebox.fi\r\n");
    $response = smtpRead($socket);

    // AUTH LOGIN
    smtpWrite($socket, "AUTH LOGIN\r\n");
    $response = smtpRead($socket);
    if (substr($response, 0, 3) !== '334') {
        fclose($socket);
        return "AUTH epäonnistui: {$response}";
    }

    // Käyttäjänimi (base64)
    smtpWrite($socket, base64_encode($user) . "\r\n");
    $response = smtpRead($socket);
    if (substr($response, 0, 3) !== '334') {
        fclose($socket);
        return "Käyttäjänimi epäonnistui: {$response}";
    }

    // Salasana (base64)
    smtpWrite($socket, base64_encode($pass) . "\r\n");
    $response = smtpRead($socket);
    if (substr($response, 0, 3) !== '235') {
        fclose($socket);
        return "Kirjautuminen epäonnistui: {$response}";
    }

    // MAIL FROM
    smtpWrite($socket, "MAIL FROM:<{$from}>\r\n");
    $response = smtpRead($socket);
    if (substr($response, 0, 3) !== '250') {
        fclose($socket);
        return "MAIL FROM epäonnistui: {$response}";
    }

    // RCPT TO
    smtpWrite($socket, "RCPT TO:<{$to}>\r\n");
    $response = smtpRead($socket);
    if (substr($response, 0, 3) !== '250') {
        fclose($socket);
        return "RCPT TO epäonnistui: {$response}";
    }

    // DATA
    smtpWrite($socket, "DATA\r\n");
    $response = smtpRead($socket);
    if (substr($response, 0, 3) !== '354') {
        fclose($socket);
        return "DATA epäonnistui: {$response}";
    }

    // Sähköpostin headerit ja sisältö
    $encodedSubject = '=?UTF-8?B?' . base64_encode($subject) . '?=';
    $encodedFromName = '=?UTF-8?B?' . base64_encode($fromName) . '?=';
    $encodedReplyName = '=?UTF-8?B?' . base64_encode($replyToName) . '?=';
    $date = date('r');

    $msg = "Date: {$date}\r\n";
    $msg .= "From: {$encodedFromName} <{$from}>\r\n";
    $msg .= "To: <{$to}>\r\n";
    $msg .= "Reply-To: {$encodedReplyName} <{$replyToEmail}>\r\n";
    $msg .= "Subject: {$encodedSubject}\r\n";
    $msg .= "MIME-Version: 1.0\r\n";
    $msg .= "Content-Type: text/plain; charset=UTF-8\r\n";
    $msg .= "Content-Transfer-Encoding: 8bit\r\n";
    $msg .= "X-Mailer: StorageBox.fi Contact Form\r\n";
    $msg .= "\r\n";
    // Escape rivit jotka alkavat pisteellä (SMTP dot-stuffing)
    $msg .= str_replace("\r\n.", "\r\n..", $body);
    $msg .= "\r\n.\r\n";

    smtpWrite($socket, $msg);
    $response = smtpRead($socket);
    if (substr($response, 0, 3) !== '250') {
        fclose($socket);
        return "Lähetys epäonnistui: {$response}";
    }

    // QUIT
    smtpWrite($socket, "QUIT\r\n");
    fclose($socket);

    return true;
}

function smtpWrite($socket, $data) {
    fwrite($socket, $data);
}

function smtpRead($socket) {
    $response = '';
    while ($line = fgets($socket, 515)) {
        $response .= $line;
        // Viimeinen rivi: kolme numeroa + välilyönti
        if (isset($line[3]) && $line[3] === ' ') {
            break;
        }
    }
    return trim($response);
}