guid3d · guid3d · May 17, 2026 · May 17, 2026 · May 17, 2026 · May 17, 2026
diff --git a/.claude/worktrees/sharp-lehmann b/.claude/worktrees/sharp-lehmann
diff --git a/package-lock.json b/package-lock.json
diff --git a/package.json b/package.json
@@ -9,6 +9,7 @@
     "lint": "next lint"
   },
   "dependencies": {
+    "@google/generative-ai": "^0.24.1",
     "@mantine/carousel": "^8.3.10",
     "@mantine/core": "^8.3.10",
     "@mantine/dates": "^8.3.10",

diff --git a/src/app/api/emoji-suggest/route.ts b/src/app/api/emoji-suggest/route.ts
@@ -0,0 +1,64 @@
+import { GoogleGenerativeAI } from "@google/generative-ai";
+import { NextRequest, NextResponse } from "next/server";
+
+const genAI = new GoogleGenerativeAI(
+  process.env.GOOGLE_GENERATIVE_AI_API_KEY!
+);
+
+// In-memory store: IP → { request count, window expiry }
+const rateLimitMap = new Map<string, { count: number; resetAt: number }>();
+const RATE_LIMIT = 20; // max requests per IP per window
+const WINDOW_MS = 60_000; // 1 minute
+
+// Returns true if IP has exceeded the rate limit. Prunes expired entries on each call.
+function isRateLimited(ip: string): boolean {
+  const now = Date.now();
+  for (const [key, val] of rateLimitMap) {
+    if (now > val.resetAt) rateLimitMap.delete(key);
+  }
+  const entry = rateLimitMap.get(ip);
+  if (!entry || now > entry.resetAt) {
+    rateLimitMap.set(ip, { count: 1, resetAt: now + WINDOW_MS });
+    return false;
+  }
+  if (entry.count >= RATE_LIMIT) return true;
+  entry.count++;
+  return false;
+}
+
+export async function POST(req: NextRequest) {
+  const ip =
+    req.headers.get("x-forwarded-for")?.split(",")[0].trim() ?? "unknown";
+
+  if (isRateLimited(ip)) {
+    return NextResponse.json(
+      { error: "Too many requests" },
+      { status: 429 }
+    );
+  }
+
+  const { name } = await req.json();
+  if (!name?.trim()) return NextResponse.json({ emojis: [] });
+
+  // Sanitize: cap length and strip quote chars to prevent prompt injection
+  const safeName = String(name).trim().slice(0, 100).replace(/["\\`]/g, "");
+  if (!safeName) return NextResponse.json({ emojis: [] });
+
+  try {
+    const model = genAI.getGenerativeModel({ model: "gemini-2.5-flash-lite" });
+    const result = await model.generateContent(
+      `Given the transaction name: "${safeName}", suggest 5 relevant emojis. Reply with ONLY the 5 emojis separated by spaces, nothing else. No words, no punctuation, just emojis.`
+    );
+    const text = result.response.text().trim();
+    // Segment by grapheme cluster so multi-codepoint emojis (e.g. 👨‍👩‍👧) aren't split,
+    // then keep only pictographic emojis (excludes digits/punctuation that match \p{Emoji})
+    const emojis = [...new Intl.Segmenter().segment(text)]
+      .map((s) => s.segment)
+      .filter((s) => /\p{Extended_Pictographic}/u.test(s))
+      .slice(0, 5);
+
+    return NextResponse.json({ emojis });
+  } catch {
+    return NextResponse.json({ emojis: [] });
+  }
+}
diff --git a/src/app/group/[groupId]/components/TabTransactions.tsx b/src/app/group/[groupId]/components/TabTransactions.tsx
@@ -9,7 +9,7 @@ import {
   Text,
   Title,
   rem,
-  useMantineColorScheme,
+  useComputedColorScheme,
 } from "@mantine/core";
 import { TotalSpendData } from "@/types";
 import UserAvatar from "@/components/UserAvatar";
@@ -26,7 +26,7 @@ type TabTransactionsProps = {
 };
 
 const TabTransactions = ({ groupData, localUserId }: TabTransactionsProps) => {
-  const { colorScheme } = useMantineColorScheme();
+  const colorScheme = useComputedColorScheme();
   const router = useRouter();
   const { groupId } = useParams<{ groupId: string }>();
   const { data, isPending, error } = useTransactions(groupId);

diff --git a/src/app/layout.tsx b/src/app/layout.tsx
@@ -27,7 +27,7 @@ const RootLayout = ({ children }: { children: React.ReactNode }) => {
         />
       </head>
       <body>
-        <MantineProvider theme={theme}>
+        <MantineProvider theme={theme} defaultColorScheme="auto">
           <ReactQueryClientProvider>{children}</ReactQueryClientProvider>
         </MantineProvider>
       </body>

diff --git a/src/components/AddEditTransactionModal/components/PageSetDetails.tsx b/src/components/AddEditTransactionModal/components/PageSetDetails.tsx
@@ -22,7 +22,7 @@ const PageSetDetails = ({ form }: PageSetDetailsProps) => {
           </Text>
         </Center>
         <Center>
-          <EmojiActionButtion form={form} />
+          <EmojiActionButtion form={form} suggestionQuery={form.values.name} />
         </Center>
         <BigTextInput
           placeholder="Name"

diff --git a/src/components/AddParticipantModal/components/PageSetPayment.tsx b/src/components/AddParticipantModal/components/PageSetPayment.tsx
@@ -4,6 +4,7 @@ import { UseFormReturnType } from "@mantine/form";
 import { Participant } from "@/types";
 import BigTextInput from "@/components/BigTextInput";
 import PaymentForm from "@/components/PaymentForm";
+import { randomPersonEmoji } from "@/utils/randomEmoji";
 
 type PageSetPaymentProps = {
   disabledPreferredPaymentMethod?: boolean;
@@ -18,7 +19,15 @@ const PageSetPayment = ({
     <Container>
       <Stack gap="xs">
         <Center>
-          <EmojiActionButtion form={form} />
+          <EmojiActionButtion
+            form={form}
+            onRandomize={() =>
+              form.setFieldValue("avatar", {
+                emoji: randomPersonEmoji(),
+                unified: "",
+              })
+            }
+          />
         </Center>
         <Center>
           <BigTextInput

diff --git a/src/components/AddParticipantModal/index.tsx b/src/components/AddParticipantModal/index.tsx
@@ -78,7 +78,8 @@ const AddParticipantModal = ({
               : null,
           "paymentMethod.iban":
             !disabledPreferredPaymentMethod &&
-            values.selectedPaymentMethod === PaymentMethodType.Iban
+            values.selectedPaymentMethod === PaymentMethodType.Iban &&
+            values.paymentMethod.iban.trim().length > 0
               ? validateIban(values.paymentMethod.iban)
               : null,
         };

diff --git a/src/components/EmojiActionButtion.tsx b/src/components/EmojiActionButtion.tsx
@@ -6,13 +6,15 @@ import {
   Modal as MantineModal,
   Stack,
   Indicator,
+  Loader,
 } from "@mantine/core";
 import { Theme } from "emoji-picker-react";
 import dynamic from "next/dynamic";
 import { useDisclosure, useMediaQuery } from "@mantine/hooks";
-import { IconChevronLeft } from "@tabler/icons-react";
+import { IconChevronLeft, IconPencil, IconRefresh } from "@tabler/icons-react";
 import { UseFormReturnType } from "@mantine/form";
-import { IconPencil } from "@tabler/icons-react";
+import { useEffect, useRef, useState } from "react";
+import { useEmojiSuggestions } from "@/hooks/useEmojiSuggestions";
 
 const Picker = dynamic(
   () => {
@@ -23,15 +25,38 @@ const Picker = dynamic(
 
 type EmojiActionButtionProps = {
   form: UseFormReturnType<any>;
+  suggestionQuery?: string;
+  onRandomize?: () => void;
 };
 
-const EmojiActionButtion = ({ form }: EmojiActionButtionProps) => {
+const EmojiActionButtion = ({
+  form,
+  suggestionQuery,
+  onRandomize,
+}: EmojiActionButtionProps) => {
   const [opened, { open, close }] = useDisclosure(false);
   const isMobile = useMediaQuery("(max-width: 50em)") || false;
-  // const [chosenEmoji, setChosenEmoji] = useState<StoreEmojiData>({
-  //   emoji: form.values.avatar.emoji,
-  //   unified: form.values.avatar.unified,
-  // });
+  const wasManuallySet = useRef(false);
+  const [suggestionIndex, setSuggestionIndex] = useState(0);
+  const { suggestions, loading } = useEmojiSuggestions(suggestionQuery ?? "");
+
+  useEffect(() => {
+    if (!wasManuallySet.current && suggestions.length > 0) {
+      form.setFieldValue("avatar", { emoji: suggestions[0], unified: "" });
+      setSuggestionIndex(0);
+    }
+  }, [suggestions]);
+
+  const handleCycle = () => {
+    if (suggestions.length < 2) return;
+    const next = (suggestionIndex + 1) % suggestions.length;
+    setSuggestionIndex(next);
+    form.setFieldValue("avatar", { emoji: suggestions[next], unified: "" });
+  };
+
+  const showCycleButton =
+    suggestions.length > 1 && !wasManuallySet.current && !opened;
+
   return (
     <>
       <MantineModal.Root
@@ -68,15 +93,14 @@ const EmojiActionButtion = ({ form }: EmojiActionButtionProps) => {
               </Center>
               <Center>
                 <Picker
-                  // style={{ border: "none" }}
                   height={390}
                   theme={Theme.AUTO}
                   onEmojiClick={(res) => {
+                    wasManuallySet.current = true;
                     form.setFieldValue("avatar", {
                       emoji: res.emoji,
                       unified: res.unified,
                     });
-                    // setChosenEmoji({ emoji: res.emoji, unified: res.unified });
                     close();
                   }}
                   previewConfig={{ showPreview: false }}
@@ -90,23 +114,53 @@ const EmojiActionButtion = ({ form }: EmojiActionButtionProps) => {
       {!opened && (
         <Indicator
           color="gray"
-          onClick={open}
           offset={13}
           position="bottom-end"
           size={35}
           withBorder
           label={<IconPencil size={20} width={20} height={20} stroke={1.5} />}
+          onClick={open}
         >
-          <ActionIcon
-            variant="default"
-            size={rem(100)}
-            radius={rem(100)}
-            onClick={open}
-          >
-            <Title order={1} style={{ fontSize: rem(60) }}>
-              {form.values.avatar.emoji}
-            </Title>
-          </ActionIcon>
+          <div style={{ position: "relative" }}>
+            <ActionIcon
+              variant="default"
+              size={rem(100)}
+              radius={rem(100)}
+              onClick={open}
+              style={{
+                opacity: loading && !wasManuallySet.current ? 0.5 : 1,
+                transition: "opacity 0.2s",
+              }}
+            >
+              {loading && !wasManuallySet.current ? (
+                <Loader size="sm" />
+              ) : (
+                <Title order={1} style={{ fontSize: rem(60) }}>
+                  {form.values.avatar.emoji}
+                </Title>
+              )}
+            </ActionIcon>
+            {(showCycleButton || onRandomize) && (
+              <ActionIcon
+                variant="default"
+                size={rem(28)}
+                radius={rem(28)}
+                style={{
+                  position: "absolute",
+                  bottom: 0,
+                  left: 0,
+                  zIndex: 1,
+                }}
+                onClick={(e) => {
+                  e.stopPropagation();
+                  if (onRandomize) onRandomize();
+                  else handleCycle();
+                }}
+              >
+                <IconRefresh size={14} stroke={1.5} />
+              </ActionIcon>
+            )}
+          </div>
         </Indicator>
       )}
     </>

diff --git a/src/components/ToggleDarkLightMode.tsx b/src/components/ToggleDarkLightMode.tsx
@@ -1,27 +1,29 @@
 import {
   rem,
   UnstyledButton,
-  useComputedColorScheme,
   useMantineColorScheme,
 } from "@mantine/core";
-import { IconMoonFilled, IconSunFilled } from "@tabler/icons-react";
+import {
+  IconBrightnessAutoFilled,
+  IconMoonFilled,
+  IconSunFilled,
+} from "@tabler/icons-react";
 
 const ToggleDarkLightMode = () => {
   const { colorScheme, setColorScheme } = useMantineColorScheme();
-  const computedColorScheme = useComputedColorScheme();
-  const toggleColorScheme = () => {
-    setColorScheme(computedColorScheme === "dark" ? "light" : "dark");
+
+  const cycleColorScheme = () => {
+    if (colorScheme === "light") setColorScheme("dark");
+    else if (colorScheme === "dark") setColorScheme("auto");
+    else setColorScheme("light");
   };
 
   return (
-    <>
-      <UnstyledButton lightHidden onClick={() => toggleColorScheme()}>
-        <IconMoonFilled style={{ width: rem(16) }} />
-      </UnstyledButton>
-      <UnstyledButton darkHidden onClick={() => toggleColorScheme()}>
-        <IconSunFilled style={{ width: rem(16) }} />
-      </UnstyledButton>
-    </>
+    <UnstyledButton onClick={cycleColorScheme}>
+      {colorScheme === "light" && <IconSunFilled style={{ width: rem(16) }} />}
+      {colorScheme === "dark" && <IconMoonFilled style={{ width: rem(16) }} />}
+      {colorScheme === "auto" && <IconBrightnessAutoFilled style={{ width: rem(16) }} />}
+    </UnstyledButton>
   );
 };