<?php
/**
 * Contact Form Handler
 * Processes form submissions and sends emails via SMTP or PHP mail()
 * Also saves all inquiries locally as backup
 */

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

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

require_once __DIR__ . '/SmtpMailer.php';
require_once __DIR__ . '/../includes/form-protection.php';

// Load email configuration from settings.json or fallback to smtp-config.php
$emailConfig = null;
$settingsPath = __DIR__ . '/../content/settings.json';

if (file_exists($settingsPath)) {
    $settings = json_decode(file_get_contents($settingsPath), true);
    if (!empty($settings['email'])) {
        $emailConfig = $settings['email'];
    }
}

// Fallback: legacy smtp-config.php (for existing installations)
if (!$emailConfig && file_exists(__DIR__ . '/smtp-config.php')) {
    require_once __DIR__ . '/smtp-config.php';
    $emailConfig = [
        'method' => 'smtp',
        'recipientEmail' => defined('SMTP_FROM_EMAIL') ? SMTP_FROM_EMAIL : '',
        'fromEmail' => defined('SMTP_FROM_EMAIL') ? SMTP_FROM_EMAIL : '',
        'fromName' => defined('SMTP_FROM_NAME') ? SMTP_FROM_NAME : '',
        'smtpHost' => defined('SMTP_HOST') ? SMTP_HOST : '',
        'smtpPort' => defined('SMTP_PORT') ? SMTP_PORT : 587,
        'smtpUsername' => defined('SMTP_USERNAME') ? SMTP_USERNAME : '',
        'smtpPassword' => defined('SMTP_PASSWORD') ? SMTP_PASSWORD : '',
        'smtpEncryption' => defined('SMTP_ENCRYPTION') ? SMTP_ENCRYPTION : 'tls',
    ];
}

// Path to mail backup file
$mailsFile = __DIR__ . '/../content/mails.json';

/**
 * Remove newlines from string (header injection protection)
 */
function sanitizeHeaderValue($value) {
    return str_replace(["\r", "\n", "\t"], '', trim($value));
}

function parseConfiguredEmailList($value): array {
    $rawItems = is_array($value) ? $value : explode(',', (string)$value);
    $emails = [];

    foreach ($rawItems as $item) {
        foreach (explode(',', (string)$item) as $email) {
            $email = sanitizeHeaderValue($email);
            if ($email !== '' && filter_var($email, FILTER_VALIDATE_EMAIL)) {
                $emails[] = $email;
            }
        }
    }

    return array_values(array_unique($emails));
}

/**
 * Save email locally as backup
 */
function saveMailBackup($filePath, $mailData) {
    return raijuJsonUpdate($filePath, function (array &$mails) use ($mailData): void {
        array_unshift($mails, $mailData);
        $mails = array_slice($mails, 0, 500);
    });
}

// Get and sanitize form data
$lang = $_POST['lang'] ?? 'de';
$name = sanitizeHeaderValue($_POST['name'] ?? '');
$email = sanitizeHeaderValue($_POST['email'] ?? '');
$phone = sanitizeHeaderValue($_POST['phone'] ?? '');
$occasion = sanitizeHeaderValue($_POST['occasion'] ?? '');
$date = sanitizeHeaderValue($_POST['date'] ?? '');
$message = trim($_POST['message'] ?? '');
$clientKey = raijuFormClientKey();

if (!raijuFormReserveRequest($clientKey)) {
    http_response_code(429);
    echo json_encode([
        'success' => false,
        'message' => $lang === 'de'
            ? 'Zu viele Versuche. Bitte versuchen Sie es später erneut.'
            : 'Too many attempts. Please try again later.'
    ]);
    exit;
}

// Honeypot check. Return a neutral success response so simple bots cannot
// distinguish this from a real submission, but do not store or send anything.
if (!empty($_POST['website'])) {
    raijuFormRecordAttempt($clientKey, false);
    echo json_encode([
        'success' => true,
        'message' => $lang === 'de'
            ? 'Vielen Dank für Ihre Nachricht!'
            : 'Thank you for your message!'
    ]);
    exit;
}

// Validation
$errors = [];

if (empty($name)) {
    $errors[] = $lang === 'de' ? 'Name ist erforderlich' : 'Name is required';
}

if (empty($email) || !filter_var($email, FILTER_VALIDATE_EMAIL)) {
    $errors[] = $lang === 'de' ? 'Gültige E-Mail ist erforderlich' : 'Valid email is required';
}

if (empty($occasion)) {
    $errors[] = $lang === 'de' ? 'Anlass ist erforderlich' : 'Occasion is required';
}

if (empty($message)) {
    $errors[] = $lang === 'de' ? 'Nachricht ist erforderlich' : 'Message is required';
}

if (!empty($errors)) {
    echo json_encode(['success' => false, 'message' => implode(', ', $errors)]);
    exit;
}

if (raijuFormLooksLikeSpam([$name, $email, $phone, $occasion, $date, $message])) {
    raijuFormRecordAttempt($clientKey, false);
    echo json_encode([
        'success' => false,
        'message' => $lang === 'de'
            ? 'Die Nachricht konnte nicht gesendet werden. Bitte prüfen Sie Ihre Eingaben.'
            : 'The message could not be sent. Please check your input.'
    ]);
    exit;
}

$tokenResult = raijuValidateFormToken($_POST['form_token'] ?? null, 'contact');
if (empty($tokenResult['valid'])) {
    raijuFormRecordAttempt($clientKey, false);
    $newToken = raijuCreateFormToken('contact');
    http_response_code(400);
    echo json_encode([
        'success' => false,
        'formToken' => $newToken,
        'message' => $lang === 'de'
            ? 'Das Formular ist abgelaufen oder wurde zu schnell gesendet. Bitte versuchen Sie es erneut.'
            : 'The form expired or was submitted too quickly. Please try again.'
    ]);
    exit;
}

// Compose email
$subject = ($lang === 'de' ? 'Anfrage über Website: ' : 'Website inquiry: ') . $occasion;

$body = $lang === 'de'
    ? "Neue Anfrage über das Kontaktformular\n"
    : "New inquiry via contact form\n";
$body .= str_repeat('-', 40) . "\n\n";

$body .= ($lang === 'de' ? "Name: " : "Name: ") . $name . "\n";
$body .= ($lang === 'de' ? "E-Mail: " : "Email: ") . $email . "\n";

if ($phone) {
    $body .= ($lang === 'de' ? "Telefon: " : "Phone: ") . $phone . "\n";
}

$body .= ($lang === 'de' ? "Anlass: " : "Occasion: ") . $occasion . "\n";

if ($date) {
    $formattedDate = date('d.m.Y', strtotime($date));
    $body .= ($lang === 'de' ? "Gewünschtes Datum: " : "Preferred date: ") . $formattedDate . "\n";
}

$body .= "\n" . ($lang === 'de' ? "Nachricht:\n" : "Message:\n");
$body .= str_repeat('-', 40) . "\n";
$body .= $message . "\n";
$body .= str_repeat('-', 40) . "\n";

// Send email when configured. Valid submissions are stored locally even when
// email delivery is disabled or misconfigured, so contact requests are not lost.
$sent = false;
$method = $emailConfig['method'] ?? 'inactive';
$toRecipients = parseConfiguredEmailList($emailConfig['recipientEmail'] ?? '');
$bccRecipients = parseConfiguredEmailList($emailConfig['bccEmail'] ?? '');
$to = implode(', ', $toRecipients);
$fromEmail = sanitizeHeaderValue($emailConfig['fromEmail'] ?? '') ?: ($toRecipients[0] ?? '');
$fromName = sanitizeHeaderValue($emailConfig['fromName'] ?? '');
$replyToEmail = filter_var($email, FILTER_VALIDATE_EMAIL) ? $email : '';
$isEmailConfigured = $emailConfig
    && $method !== 'inactive'
    && !empty($toRecipients);

if ($isEmailConfigured && $method === 'smtp') {
    $mailer = new SmtpMailer(
        $emailConfig['smtpHost'] ?? '',
        intval($emailConfig['smtpPort'] ?? 587),
        $emailConfig['smtpUsername'] ?? '',
        $emailConfig['smtpPassword'] ?? '',
        $emailConfig['smtpEncryption'] ?? 'tls'
    );

    $sent = $mailer->send(
        $toRecipients,
        $subject,
        $body,
        $fromEmail,
        $fromName,
        $replyToEmail,
        $bccRecipients
    );
} elseif ($isEmailConfigured && $method === 'sendmail') {
    // PHP mail() — requires server IP to be whitelisted for sending
    $headers = [];
    $headers[] = 'From: ' . ($fromName ? "=?UTF-8?B?" . base64_encode($fromName) . "?= <$fromEmail>" : $fromEmail);
    if ($replyToEmail) {
        $headers[] = 'Reply-To: ' . $replyToEmail;
    }
    $headers[] = 'Content-Type: text/plain; charset=UTF-8';
    $headers[] = 'X-Mailer: Raiju CMS';

    $sent = @mail($to, '=?UTF-8?B?' . base64_encode($subject) . '?=', $body, implode("\r\n", $headers));
    foreach ($bccRecipients as $bccRecipient) {
        $sent = @mail($bccRecipient, '=?UTF-8?B?' . base64_encode($subject) . '?=', $body, implode("\r\n", $headers)) && $sent;
    }
}

$status = $sent ? 'sent' : ($isEmailConfigured ? 'send_failed' : 'local_only');
$saved = saveMailBackup($mailsFile, [
    'id' => uniqid('mail_'),
    'timestamp' => date('c'),
    'lang' => $lang,
    'formId' => 'contact',
    'formLabel' => $lang === 'de' ? 'Kontaktformular' : 'Contact form',
    'name' => $name,
    'email' => $email,
    'phone' => $phone,
    'occasion' => $occasion,
    'date' => $date,
    'message' => $message,
    'fields' => [
        ['key' => 'name', 'label' => $lang === 'de' ? 'Name' : 'Name', 'value' => $name],
        ['key' => 'email', 'label' => $lang === 'de' ? 'E-Mail' : 'Email', 'value' => $email],
        ['key' => 'phone', 'label' => $lang === 'de' ? 'Telefon' : 'Phone', 'value' => $phone],
        ['key' => 'message', 'label' => $lang === 'de' ? 'Nachricht' : 'Message', 'value' => $message],
    ],
    'status' => $status,
    'read' => false,
    'starred' => false
]);

if (!$saved) {
    http_response_code(500);
    echo json_encode([
        'success' => false,
        'message' => $lang === 'de'
            ? 'Die Nachricht konnte nicht gespeichert werden. Bitte versuchen Sie es später erneut.'
            : 'The message could not be saved. Please try again later.'
    ]);
    exit;
}

raijuFormRecordAttempt($clientKey, true);
$newToken = raijuCreateFormToken('contact');

echo json_encode([
    'success' => true,
    'status' => $status,
    'formToken' => $newToken,
    'message' => $lang === 'de'
        ? 'Vielen Dank für Ihre Nachricht!'
        : 'Thank you for your message!'
]);