diff --git a/Layout/default/Invoice/Index.php b/Layout/default/Invoice/Index.php
index 5ca715292..a171e81c4 100644
--- a/Layout/default/Invoice/Index.php
+++ b/Layout/default/Invoice/Index.php
@@ -151,7 +151,11 @@ $pagination_entity_name = "Rechnungen";
                                         <td class="<?=($total_gross < 0) ? "text-danger" : ""?>">€ <?=number_format($total_gross,2,",",".")?></td>
                                         <td><?=($invoice->billing_type == "sepa") ? "SEPA" : "Überweisung"?></td>
                                         <td><?=($invoice->billing_delivery == "email") ? "Email" : "Papier"?></td>
-                                        <td><a href="<?=self::getUrl("Invoice", "downloadInvoice", ["id" => $invoice->id])?>"><i class="fas fa-download fa-fw"></i></a></td>
+                                        <td>
+                                            <?php if($invoice->total < 0): ?>
+                                            <a class="text-danger" href="<?=self::getUrl("Invoice", "downloadInvoiceCsv", ["id" => $invoice->id])?>"><i class="fas fa-file-csv fa-fw"></i></a>
+                                            <?php endif; ?>
+                                        </td>
                                     </tr>
                                 <?php endforeach; ?>
                             </table>
diff --git a/application/Contract/Contract.php b/application/Contract/Contract.php
index 77d2e1d33..a0623e25f 100644
--- a/application/Contract/Contract.php
+++ b/application/Contract/Contract.php
@@ -63,7 +63,7 @@ class Contract extends mfBaseModel {
           $this->linkTo[] = $link;
           break;
         case "credit":
-          $this->linkFrom[] = $link;
+          $this->linkTo[] = $link;
           break;
         case "upgrade":
           $this->upgradeTo[] = $link;
@@ -89,7 +89,7 @@ class Contract extends mfBaseModel {
           $this->linkFrom[] = $link;
           break;
         case "credit":
-          $this->linkTo[] = $link;
+          $this->linkFrom[] = $link;
           break;
         case "upgrade":
           $this->upgradeFrom[] = $link;
diff --git a/application/Invoice/InvoiceController.php b/application/Invoice/InvoiceController.php
index 466c8a0bb..466082d50 100644
--- a/application/Invoice/InvoiceController.php
+++ b/application/Invoice/InvoiceController.php
@@ -124,59 +124,33 @@ class InvoiceController extends mfBaseController {
 
         readfile($pdf_path);
         exit;
+    }
 
-        /*$vat = [];
-        foreach ($invoice->positions as $p) {
-            if (!array_key_exists($p->vatrate, $vat)) {
-                $vat[$p->vatrate] = 0;
-            }
-            $vat[$p->vatrate] += $p->price_gross - ($p->price * $p->amount);
+    protected function downloadInvoiceCsv() {
+        $id = $this->request->id;
+        if (!is_numeric($id) || !$id) {
+            $this->layout()->setFlash("Rechnung nicht gefunden", "error");
+            $this->redirect("Invoice");
         }
 
-        $pdf_vars = [
-            "invoice" => $invoice,
-            "vat" => $vat,
-            "bank_iban" => TT_INVOICE_BANK_IBAN,
-            "bank_bic" => TT_INVOICE_BANK_BIC,
-            "bank_bank"=> TT_INVOICE_BANK_BANK,
-            "bank_owner" => TT_INVOICE_BANK_OWNER
-        ];
+        $invoice = new Invoice($id);
+        if (!$invoice->id) {
+            $this->layout()->setFlash("Rechnung nicht gefunden", "error");
+            $this->redirect("Invoice");
+        }
 
-        // Replace placeholders in header
-        $headerHtml = file_get_contents(BASEDIR . "/Layout/default/Invoice/PDF_HEADER.html");
-        $headerHtml = str_replace("{{ basedir }}", BASEDIR, $headerHtml);
-        $headerHtml = str_replace("{{ addressLine_1 }}", $invoice->company ? $invoice->company : "", $headerHtml);
-        $headerHtml = str_replace("{{ addressLine_2 }}", $invoice->firstname . " " . $invoice->lastname, $headerHtml);
-        $headerHtml = str_replace("{{ addressLine_3 }}", nl2br($invoice->street), $headerHtml);
-        $headerHtml = str_replace("{{ addressLine_4 }}", $invoice->zip . " " . $invoice->city, $headerHtml);
-        $headerHtml = str_replace("{{ addressLine_5 }}", $invoice->country != "Österreich" ? $invoice->country : "", $headerHtml);
-        $headerHtml = str_replace("{{ customerNumber }}", $invoice->customer_number, $headerHtml);
-        $headerHtml = str_replace("{{ billingAccount }}", $invoice->fibu_account_number, $headerHtml);
-        $headerHtml = str_replace("{{ invoiceNumber }}", $invoice->invoice_number, $headerHtml);
-        $headerHtml = str_replace("{{ invoiceDate }}", date("d.m.Y", $invoice->invoice_date), $headerHtml);
-        $headerHtml = str_replace("{{ vatHtml }}", $invoice->uid ? "<tr><td>Ihre UID:</td><td>" . $invoice->uid . "</td></tr>" : "", $headerHtml);
-        $headerHtml = str_replace("{{ qrCodeSrc }}", $this->getBankQRCode($invoice->invoice_number, round($invoice->total_gross, 2)), $headerHtml);
-
-        $headerFile = BASEDIR . "/var/temp/invoice_header-" . date("U") . "-" . rand(1000, 9999) . ".html";
-        file_put_contents($headerFile, $headerHtml);
-
-
-        // Replace placeholders in header
-        $footerHtml = file_get_contents(BASEDIR . "/Layout/default/Invoice/PDF_FOOTER.html");
-        $footerHtml = str_replace("{{ bank_iban }}", TT_INVOICE_BANK_IBAN_FORMATTED, $footerHtml);
-        $footerHtml = str_replace("{{ bank_bic }}", TT_INVOICE_BANK_BIC, $footerHtml);
-        $footerHtml = str_replace("{{ bank_bank }}", TT_INVOICE_BANK_BANK, $footerHtml);
-        $footerHtml = str_replace("{{ bank_owner }}", TT_INVOICE_BANK_OWNER, $footerHtml);
-
-
-        $footerFile = BASEDIR . "/var/temp/invoice_footer-" . date("U") . "-" . rand(1000, 9999) . ".html";
-        file_put_contents($footerFile, $footerHtml);
-
-
-        $pdf = new PdfForm("Invoice/PDF_MAIN", $pdf_vars);
-        $wkhtmltopdfArgs = "--header-html $headerFile --footer-html $footerFile";
-        $pdf->download($invoice->invoice_number . ".pdf", $wkhtmltopdfArgs);*/
+        if(!$invoice->positions) {
+            $this->layout()->setFlash("Keine Rechnungspositionen vorhanden", "error");
+            $this->redirect("Invoice");
+        }
 
+        $tpl = new Layout();
+        $tpl->setTemplate("Invoice/invoicepositions.csv");
+        $tpl->set("invoice", $invoice);
+        $tpl->display();
+        //$csv = $tpl->render();
+        //echo $csv;
+        exit;
     }
 
 
diff --git a/application/Invoiceposition/Invoiceposition.php b/application/Invoiceposition/Invoiceposition.php
index 203ba60e6..a602f1ee6 100644
--- a/application/Invoiceposition/Invoiceposition.php
+++ b/application/Invoiceposition/Invoiceposition.php
@@ -1,6 +1,8 @@
 <?php
 
 class Invoiceposition extends mfBaseModel {
+    private $invoice;
+    private $contract;
 
     public function setOption($name, $value) {
         $options = $this->getOptions;
@@ -65,4 +67,52 @@ class Invoiceposition extends mfBaseModel {
 
         //$this->log->debug("Cloned Invoiceposition $old_id");
     }
+
+    public function getProperty($name) {
+        if($this->$name == null) {
+
+            if(!$this->id) {
+                return null;
+            }
+
+            if($name == "creator") {
+                $this->creator = mfValuecache::singleton()->get("Worker-id-".$this->create_by);
+                if($this->creator === null) {
+                    $this->creator = new User($this->create_by);
+                    if($this->creator->id) {
+                        mfValuecache::singleton()->set("Worker-id-".$this->create_by, $this->creator);
+                    }
+                }
+                return $this->creator;
+            }
+
+            if($name == "editor") {
+                $this->editor = mfValuecache::singleton()->get("Worker-id-".$this->edit_by);
+                if($this->editor === null) {
+                    $this->editor = new User($this->edit_by);
+                    if($this->editor->id) {
+                        mfValuecache::singleton()->set("Worker-id-".$this->edit_by, $this->editor);
+                    }
+                }
+                return $this->editor;
+            }
+
+            $classname = ucfirst($name);
+            $idfield = $name."_id";
+            $this->$name = mfValuecache::singleton()->get("mfObjectmodel-$name-".$this->$idfield);
+            if(!$this->$name) {
+                $this->$name = new $classname($this->$idfield);
+            }
+
+            if($this->$name->id) {
+                mfValuecache::singleton()->set("mfObjectmodel-$name-".$this->$name->id, $this->$name);
+                return $this->$name;
+            } else {
+                return null;
+            }
+
+        }
+
+        return $this->$name;
+    }
 }
\ No newline at end of file
diff --git a/scripts/contract/mark-credit-contracts-as-credit.php b/scripts/contract/mark-credit-contracts-as-credit.php
new file mode 100644
index 000000000..6fb300dec
--- /dev/null
+++ b/scripts/contract/mark-credit-contracts-as-credit.php
@@ -0,0 +1,24 @@
+#!/usr/bin/php
+<?php
+
+//require 'vendor/autoload.php';
+require("../../config/config.php");
+
+define('FRONKDB_SQLDEBUG',false);
+error_reporting(E_ALL & ~(E_NOTICE | E_STRICT | E_DEPRECATED));
+
+require_once(LIBDIR."/mvcfronk/mfRouter/mfRouter.php");
+require_once(LIBDIR."/mvcfronk/mfBase/mfBaseModel.php");
+require_once(LIBDIR."/mvcfronk/mfBase/mfBaseController.php");
+
+$me = new User(1);
+
+foreach(ContractLinkModel::getAll() as $link) {
+    if($link->origin->price <= 0) continue;
+
+    if($link->contract->price < 0) {
+        $link->type = "credit";
+        $link->save();
+        echo "fixed link ".$link->id." origin contract ".$link->origin_contract_id."\n";
+    }
+}