From c25ab488808a84d14ee4c8945942d1259a5107bc Mon Sep 17 00:00:00 2001
From: Theis <theis.gaedigk@icloud.com>
Date: Mon, 18 May 2026 19:14:48 +0200
Subject: [PATCH] fully implemented tanstack query

---
 frontend/src/pages/MainForm.tsx | 96 ++++++++++++++++++---------------
 frontend/src/utils/api/form.ts  | 26 +++++++++
 frontend/src/utils/sender.ts    | 33 ------------
 3 files changed, 80 insertions(+), 75 deletions(-)
 create mode 100644 frontend/src/utils/api/form.ts
 delete mode 100644 frontend/src/utils/sender.ts

diff --git a/frontend/src/pages/MainForm.tsx b/frontend/src/pages/MainForm.tsx
index 7c9c3f5..23cfef6 100644
--- a/frontend/src/pages/MainForm.tsx
+++ b/frontend/src/pages/MainForm.tsx
@@ -18,14 +18,15 @@ import {
   Modal,
   ModalDialog,
   ModalClose,
+  CircularProgress,
 } from "@mui/joy";
-import { submitFormData } from "../utils/sender";
+import { submitFormData } from "../utils/api/form";
 import type { FormData, Message } from "../config/interfaces.config";
 import PersonIcon from "@mui/icons-material/Person";
 import QrCodeIcon from "@mui/icons-material/QrCode";
 import TranslateIcon from "@mui/icons-material/Translate";
 import qrCode from "../assets/PayPal-QR-Code.png";
-import { useQuery } from "@tanstack/react-query";
+import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
 import { confirmUser, fetchUsers } from "../utils/api/users";
 
 const PAYMENT_METHODS = ["bar", "paypal", "andere"] as const;
@@ -83,6 +84,7 @@ const Field = ({
 
 export const MainForm = () => {
   const { t, i18n } = useTranslation();
+  const queryClient = useQueryClient();
 
   const [invoice, setInvoice] = useState(false);
   const [msg, setMsg] = useState<Message | null>(null);
@@ -114,6 +116,32 @@ export const MainForm = () => {
     queryFn: () => confirmUser(selectedUser),
   });
 
+  const {
+    mutate: mutateForm,
+    isSuccess: mutateFormIsSuccess,
+    isPending: mutateFormIsPending,
+    isError: mutateFormIsError,
+  } = useMutation({
+    mutationFn: () => submitFormData(formData, selectedUser),
+  });
+
+  // Redirecting to success page if mutation was successful
+  useEffect(() => {
+    if (mutateFormIsSuccess) {
+      queryClient.invalidateQueries({ queryKey: ["user", selectedUser] });
+      document.location.href = `/success?id=${nextID}&tickets=${formData.tickets}`;
+    }
+
+    if (mutateFormIsError) {
+      queryClient.invalidateQueries({ queryKey: ["user", selectedUser] });
+      setMsg({
+        type: "danger",
+        headline: t("error"),
+        text: t("form-submission-failed"),
+      });
+    }
+  }, [mutateFormIsSuccess, mutateFormIsError]);
+
   // Setting the nextID after a user is selected
   useEffect(() => {
     if (!userData) return;
@@ -152,27 +180,6 @@ export const MainForm = () => {
     }
   }, [formData.paymentMethod]);
 
-  const handleSubmit = async () => {
-    try {
-      const result = await submitFormData(formData, selectedUser || "");
-      if (result.success) {
-        document.location.href = `/success?id=${nextID}&tickets=${formData.tickets}`;
-      } else {
-        setMsg({
-          type: "danger",
-          headline: t("form-submission-failed"),
-          text: result.error || t("form-submission-failed"),
-        });
-      }
-    } catch (error) {
-      setMsg({
-        type: "danger",
-        headline: t("error"),
-        text: t("form-submission-failed"),
-      });
-    }
-  };
-
   // Shorthand so we don't repeat formData + onChange on every Field usage
   const fieldProps = { formData, onChange: handleChange };
 
@@ -258,7 +265,7 @@ export const MainForm = () => {
           <form
             onSubmit={(e) => {
               e.preventDefault();
-              handleSubmit();
+              mutateForm();
             }}
             className="flex flex-col gap-4"
           >
@@ -411,24 +418,29 @@ export const MainForm = () => {
               )}
             </FormControl>
 
-            {/* Submit button */}
-            <Button
-              type="submit"
-              disabled={!formData.paymentMethod}
-              size="lg"
-              sx={{
-                mt: 2,
-                borderRadius: "14px",
-                fontWeight: 700,
-                letterSpacing: "0.05em",
-                background: "linear-gradient(135deg, #2563eb, #1d4ed8)",
-                "&:hover": {
-                  background: "linear-gradient(135deg, #1d4ed8, #1e40af)",
-                },
-              }}
-            >
-              {t("submit")}
-            </Button>
+            {mutateFormIsPending ? (
+              <div className="flex items-center justify-center">
+                <CircularProgress />
+              </div>
+            ) : (
+              <Button
+                type="submit"
+                disabled={!formData.paymentMethod}
+                size="lg"
+                sx={{
+                  mt: 2,
+                  borderRadius: "14px",
+                  fontWeight: 700,
+                  letterSpacing: "0.05em",
+                  background: "linear-gradient(135deg, #2563eb, #1d4ed8)",
+                  "&:hover": {
+                    background: "linear-gradient(135deg, #1d4ed8, #1e40af)",
+                  },
+                }}
+              >
+                {t("submit")}
+              </Button>
+            )}
 
             {/* Alert message */}
             {msg && (
diff --git a/frontend/src/utils/api/form.ts b/frontend/src/utils/api/form.ts
new file mode 100644
index 0000000..0229d7f
--- /dev/null
+++ b/frontend/src/utils/api/form.ts
@@ -0,0 +1,26 @@
+import { API_BASE } from "../../config/api.config";
+import type { FormData } from "../../config/interfaces.config";
+
+export const submitFormData = async (data: FormData, username: string) => {
+  console.warn("submitFormData is fetching!");
+
+  await new Promise((resolve) => setTimeout(resolve, 3000)); // Wait 3 seconds
+
+  const response = await fetch(
+    `${API_BASE}/default/new-entry?username=${username}`,
+    {
+      method: "POST",
+      headers: {
+        "Content-Type": "application/json",
+      },
+      body: JSON.stringify(data),
+    },
+  );
+
+  if (!response.ok) {
+    const error = await response.text();
+    throw new Error(error || "Form submission failed");
+  }
+
+  return;
+};
diff --git a/frontend/src/utils/sender.ts b/frontend/src/utils/sender.ts
deleted file mode 100644
index 724447d..0000000
--- a/frontend/src/utils/sender.ts
+++ /dev/null
@@ -1,33 +0,0 @@
-import { API_BASE } from "../config/api.config";
-import type { FormData } from "../config/interfaces.config";
-
-export const submitFormData = async (
-  data: FormData,
-  username: string | null,
-) => {
-  if (username == null) {
-    return { success: false, errorCode: "x001" };
-  }
-
-  try {
-    const response = await fetch(
-      `${API_BASE}/default/new-entry?username=${username}`,
-      {
-        method: "POST",
-        headers: {
-          "Content-Type": "application/json",
-        },
-        body: JSON.stringify(data),
-      },
-    );
-
-    if (!response.ok) {
-      const errorText = await response.text();
-      return { success: false, error: `Server error: ${errorText}` };
-    }
-
-    return { success: true };
-  } catch (error) {
-    return { success: false, error: (error as Error).message };
-  }
-};