<?php
$message = '';
$name = '';
$email = '';

function sanitize_text(string $name) {
    $text = filter_var($_POST[$name], FILTER_SANITIZE_FULL_SPECIAL_CHARS);
    $text = trim($text);
    $text = stripslashes($text);
    $text = htmlspecialchars($text);

    return $text;
}

/**
 *  Sending email (Platzhalter)
 *
 *  mail(): Braucht auf dem Server einen korrekt konfigurierten Mailserver
 *  phpmailer: Bibliothek, der per Composer installiert wird. Tut ganz gut mit SMTP.
 */
function send_message_to_office($message, $name, $email) {
    return true;
}

function send_response($response_data) {
    $json = json_encode($response_data);
    if ($json === false) {
        // Avoid echo of empty string (which is invalid JSON), and
        // JSONify the error message instead:
        $json = json_encode(["jsonError" => json_last_error_msg()]);
        if ($json === false) {
            // This should not happen, but …
            $json = '{"jsonError":"unknown"}';
        }
        // Set HTTP response status code to: 500 - Internal Server Error
        http_response_code(500);
    }
    header('Content-type: application/json');
    echo $json;
}

if ($_SERVER["REQUEST_METHOD"] == "POST") {
    $response = array();

    if (
        empty($_POST['message']) ||
        empty($_POST['email']) ||
        empty($_POST['name']) ||
        $_POST['captcha'] != 'Nudelsuppe'
    ) {
        if (empty($_POST['message'])) {
            $response['errors'][] = 'Du hast keine Nachricht eingegeben.';
        }
        if (empty($_POST['email'])) {
            $response['errors'][] = 'Du hast keine E-Mail-Adresse eingegeben.';
        }
        if (empty($_POST['name'])) {
            $response['errors'][] = 'Du hast keinen Namen eingegeben.';
        }
        if ($_POST['captcha'] != 'Nudelsuppe') {
            $response['errors'][] = 'Wir glauben du bist ein Bot.';
        }
    } else {
        $message = sanitize_text('message');
        $name = sanitize_text('name');
        $email = sanitize_text('email');

        if (!send_message_to_office($message, $name, $email)) {
            $response['errors'][] = 'Deine Nachricht konnte nicht übermittelt werden.';
        } else {
            $response['status'] = 'ok';
        }
    }
    send_response($response);
} else {
    http_response_code(404);
}