ERFOLG"; ?>

<?php

/*
*		smzint/Messages (c) schmamazon.com 2025
*/

include('../Auth/index.php');
include('ready.php');

$by = filter_var($_POST["by"], FILTER_SANITIZE_STRING);
$receiver = filter_var($_POST["receiver"], FILTER_SANITIZE_STRING);
$allowedTags = "<i><b><u><strong><em><p><div><h1><h2><h3><h4><h5><h6><a><sub><sup><mark>";
$body = strip_tags($_POST["body"], $allowedTags);
$color = filter_var($_POST["color"], FILTER_SANITIZE_STRING);
$messageId = uniqid();

receiverCheck($by);
pushMetadata($messageId, $receiver, $color);


function receiverCheck($by){
  global $receiver;
  include('search.php');
  switch ($by) {
    case '0':
      if (uid($receiver) == false){
        echo "FATAL: Empfänger ($receiver) nicht gefunden (searched by ID)";
        die();
      }
      break;

    case '1':
      if (username($receiver) == false){
        echo "FATAL: Empfänger ($receiver) nicht gefunden (searched by NAME)";
      }else{
        $receiver = username($receiver);
      }
      break;
  }
}

function pushMetadata($messageId, $receiver, $color){
  $sender_info = "".$_SERVER['REMOTE_ADDR'].", ". $_SERVER['HTTP_USER_AGENT']."";

  global $dbservername;
	global $dbusername;
	global $dbpassword;
	global $dbname;
  global $uid;

  $conn = new mysqli($dbservername, $dbusername, $dbpassword, $dbname);
		if ($conn->connect_error) {
			die("Server Error");
		}
    $sql = "INSERT INTO smz_messages_metadata (message, sender, receiver, sender_info, color) VALUES ('$messageId', '$uid', '$receiver', '$sender_info', '$color')";

		if ($conn->query($sql) === TRUE) {
      echo "Metadaten erfolgreich gespeichert";
		} else {
			echo "Error: " . $sql . "<br>" . $conn->error;
		}

		$conn->close();

}


function pushData($messageId, $body, $iv, $internal_key, $external_key){
  global $dbservername;
	global $dbusername;
	global $dbpassword;
	global $dbname;

  $conn = new mysqli($dbservername, $dbusername, $dbpassword, $dbname);
		if ($conn->connect_error) {
			die("Server Error");
		}
    $sql = "INSERT INTO smz_messages_data (message_id, message_body, iv, internal_key, external_key) VALUES ('$messageId', '$body', '$iv', '$internal_key', '$external_key')";

		if ($conn->query($sql) === TRUE) {
      echo "DATA erfolgreich gespeichert";
		} else {
			echo "Error: " . $sql . "<br>" . $conn->error;
		}

		$conn->close();
}

include('keyGrab.php');
$sender_key = grabPublicKey($uid);
$receiver_key = grabPublicKey($receiver);

$aesKey = openssl_random_pseudo_bytes(32);
$iv = openssl_random_pseudo_bytes(openssl_cipher_iv_length('aes-128-cbc'));
$encryptedBody = openssl_encrypt($body, 'aes-128-cbc', $aesKey, 0, $iv);


$encryptedAesKey = '';
$encryptionOkEXT = openssl_public_encrypt($aesKey, $encryptedAesKeyEXTERNAL, $receiver_key, OPENSSL_PKCS1_PADDING);
$encryptionOkINT = openssl_public_encrypt($aesKey, $encryptedAesKeyINTERNAL, $sender_key, OPENSSL_PKCS1_PADDING);

if ($encryptionOkEXT === false) {
    die("Fehler beim Verschlüsseln des AES-Schlüssels (EXTERNAL): " . openssl_error_string());
}
if ($encryptionOkINT === false) {
    die("Fehler beim Verschlüsseln des AES-Schlüssels (INTERNAL): " . openssl_error_string());
}

$encryptedMessageBase64 = base64_encode($encryptedBody);
$encryptedAesKeyBase64EXT = base64_encode($encryptedAesKeyEXTERNAL);
$encryptedAesKeyBase64INT = base64_encode($encryptedAesKeyINTERNAL);
$ivBase64 = base64_encode($iv);

pushData($messageId, $encryptedMessageBase64, $ivBase64, $encryptedAesKeyBase64INT, $encryptedAesKeyBase64EXT);
echo "<h1>ERFOLG</1>";
 ?>