<?php

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

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

$id = filter_var($_POST["id"], FILTER_SANITIZE_STRING);
$upassword = filter_var($_POST["upass"], FILTER_SANITIZE_STRING);

function getMessageType($id){
  global $dbservername;
  global $dbusername;
  global $dbpassword;
  global $dbname;
  global $uid;
  $conn = new mysqli($dbservername, $dbusername, $dbpassword, $dbname);
  if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
  }

  $sql = "SELECT sender, receiver FROM smz_messages_metadata WHERE message='$id'";
  $result = $conn->query($sql);
  $conn->close();
  if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
      if ($row["sender"] == $uid){
        return "internal";
      }else if($row["receiver"] == $uid){
        return "external";
      }else{
        return false;
      }
    }
  } else {
    return false;
  }
}

function getData($id){
  global $dbservername;
  global $dbusername;
  global $dbpassword;
  global $dbname;
  $conn = new mysqli($dbservername, $dbusername, $dbpassword, $dbname);
  if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
  }
  $type = "".getMessageType($id)."_key";

  $sql = "SELECT message_body, iv, $type FROM smz_messages_data WHERE message_id='$id'";
  $result = $conn->query($sql);
  $conn->close();
  if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
      decrypt($row["$type"], $row["message_body"], $row["iv"]);
    }
  } else {
    return false;
  }
}

function decrypt($aeskey, $body, $iv){
  global $upassword;
  include('keyGrab.php');
  $key = grabPrivateKey($upassword);

  $decryptedAesKey = '';
  $decryptionOk = openssl_private_decrypt(base64_decode($aeskey), $decryptedAesKey, $key, OPENSSL_PKCS1_PADDING);

  if ($decryptionOk === false) {
      die("Fehler beim Entschlüsseln des AES-Schlüssels: " . openssl_error_string());
  }

  // Nachricht mit AES entschlüsseln
  $decryptedMessage = openssl_decrypt(base64_decode($body), 'aes-128-cbc', $decryptedAesKey, 0, base64_decode($iv));

  echo $decryptedMessage;
}

if(!password_verify($upassword, $upassword_hash)){
    die("Passwortfehler");
}
getData($id);

 ?>