From 5442f2f1f39b33a809ba6bca0aa08adb9445de2c Mon Sep 17 00:00:00 2001
From: Theis Gaedigk <theis.gaedigk@icloud.com>
Date: Fri, 24 Apr 2026 18:44:07 +0200
Subject: [PATCH] new feature: Error code 507 will return if you want to delete
 a loan that has not been returned

---
 FrontendV2/src/pages/MyLoansPage.tsx            |  8 ++++++++
 FrontendV2/src/utils/i18n/locales/de/de.json    |  3 ++-
 FrontendV2/src/utils/i18n/locales/en/en.json    |  3 ++-
 .../routes/app/database/loansMgmt.database.js   | 17 +++++++++++++++++
 backendV2/routes/app/loanMgmt.route.js          | 10 ++++++++++
 backendV2/server.js                             |  2 --
 changelog.md                                    |  1 +
 7 files changed, 40 insertions(+), 4 deletions(-)

diff --git a/FrontendV2/src/pages/MyLoansPage.tsx b/FrontendV2/src/pages/MyLoansPage.tsx
index 8fa5904..ef040de 100644
--- a/FrontendV2/src/pages/MyLoansPage.tsx
+++ b/FrontendV2/src/pages/MyLoansPage.tsx
@@ -84,6 +84,14 @@ export const MyLoansPage = () => {
       });
 
       if (!res.ok) {
+        if (res.status === 507) {
+          setMsgStatus("error");
+          setMsgTitle(t("error"));
+          setMsgDescription(t("error-deleting-loan-507"));
+          setIsMsg(true);
+          return;
+        }
+
         setMsgStatus("error");
         setMsgTitle(t("error"));
         setMsgDescription(t("error-deleting-loan"));
diff --git a/FrontendV2/src/utils/i18n/locales/de/de.json b/FrontendV2/src/utils/i18n/locales/de/de.json
index b02e852..353b16d 100644
--- a/FrontendV2/src/utils/i18n/locales/de/de.json
+++ b/FrontendV2/src/utils/i18n/locales/de/de.json
@@ -93,5 +93,6 @@
     "try-naas": "Klick mich",
     "naas-error": "Fehler mit no-as-a-service",
     "naas-error-desc": "Ein Fehler ist beim Kommunizieren mit no-as-a-service aufgetreten.",
-    "naas-header": "Eine gute Möglichkeit, nein zu sagen..."
+    "naas-header": "Eine gute Möglichkeit, nein zu sagen...",
+    "error-deleting-loan-507": "Die Ausleihe kann nicht gelöscht werden, da sie noch nicht zurückgegeben wurde."
 }
\ No newline at end of file
diff --git a/FrontendV2/src/utils/i18n/locales/en/en.json b/FrontendV2/src/utils/i18n/locales/en/en.json
index d093b1c..8dc1059 100644
--- a/FrontendV2/src/utils/i18n/locales/en/en.json
+++ b/FrontendV2/src/utils/i18n/locales/en/en.json
@@ -93,5 +93,6 @@
     "try-naas": "Click me",
     "naas-error": "Error with no-as-a-service",
     "naas-error-desc": "An error occurred while communicating with no-as-a-service.",
-    "naas-header": "A good way to say no..."
+    "naas-header": "A good way to say no...",
+    "error-deleting-loan-507": "The loan cannot be deleted because it has not been returned yet."
 }
\ No newline at end of file
diff --git a/backendV2/routes/app/database/loansMgmt.database.js b/backendV2/routes/app/database/loansMgmt.database.js
index 3fdc67e..aa9a261 100644
--- a/backendV2/routes/app/database/loansMgmt.database.js
+++ b/backendV2/routes/app/database/loansMgmt.database.js
@@ -234,6 +234,23 @@ export const getBorrowableItemsFromDatabase = async (
 };
 
 export const SETdeleteLoanFromDatabase = async (loanId) => {
+  const [checkIfdatesReturned] = await pool.query(
+    "SELECT take_date, returned_date FROM loans WHERE id = ? AND deleted = 0",
+    [loanId],
+  );
+
+  if (checkIfdatesReturned.length === 0) {
+    return { success: false, code: "LOAN_NOT_FOUND" };
+  }
+
+  const { take_date, returned_date } = checkIfdatesReturned[0];
+  const bothNull = take_date === null && returned_date === null;
+  const bothSet = take_date !== null && returned_date !== null;
+
+  if (!(bothNull || bothSet)) {
+    return { success: false, code: "LOAN_NOT_RETURNED" };
+  }
+
   const [result] = await pool.query(
     "UPDATE loans SET deleted = 1 WHERE id = ?;",
     [loanId],
diff --git a/backendV2/routes/app/loanMgmt.route.js b/backendV2/routes/app/loanMgmt.route.js
index 7e0c0ce..2a57f60 100644
--- a/backendV2/routes/app/loanMgmt.route.js
+++ b/backendV2/routes/app/loanMgmt.route.js
@@ -134,6 +134,16 @@ router.delete("/delete-loan/:id", authenticate, async (req, res) => {
   if (result.success) {
     res.status(200).json({ message: "Loan deleted successfully" });
   } else {
+    if (result.code === "LOAN_NOT_FOUND") {
+      res.status(404).json({ message: "Loan not found" });
+    }
+
+    if (result.code === "LOAN_NOT_RETURNED") {
+      res.status(507).json({
+        message: "Cannot delete loan that has not been returned",
+      });
+    }
+
     res.status(500).json({ message: "Failed to delete loan" });
   }
 });
diff --git a/backendV2/server.js b/backendV2/server.js
index a8d2006..61855d8 100644
--- a/backendV2/server.js
+++ b/backendV2/server.js
@@ -23,8 +23,6 @@ const app = express();
 const port = 8004;
 const naasURL = process.env.NAAS_URL;
 
-console.log(naasURL);
-
 app.use(cors());
 // Body-Parser VOR den Routen registrieren
 app.use(express.json({ limit: "10mb" }));
diff --git a/changelog.md b/changelog.md
index 54c0245..878a0db 100644
--- a/changelog.md
+++ b/changelog.md
@@ -13,6 +13,7 @@ This update provides some new features for the design. It also contains some imp
 ## Improvements
 
 - I have the error logging for the API route wehre you can take loans improved.
+- If you try to delete a loan that has not been returned yet, you will get an 507 error code.
 
 ## Fixed bugs