2 files changed, 143 insertions, 0 deletions
diff --git a/src/helpers/fetchSolution.ts b/src/helpers/fetchSolution.ts
index b7895bb..a91932a 100644
--- a/src/helpers/fetchSolution.ts
+++ b/src/helpers/fetchSolution.ts
@@ -55,6 +55,8 @@ interface SubmitDailyGuessRequest {
   state: DailyGameState;
   sig: string;
   guess?: SongGuessPayload | null;
+  username?: string;
+  groupId?: string;
 }
 
 interface SubmitDailyGuessResponse {
diff --git a/src/helpers/group.ts b/src/helpers/group.ts
new file mode 100644
index 0000000..2a10c36
--- /dev/null
+++ b/src/helpers/group.ts
@@ -0,0 +1,141 @@
+const API_URL = import.meta.env.VITE_HEARDLE_API_URL ?? "http://localhost:3001";
+
+export const GROUP_MEMBERSHIP_STORAGE_KEY = "groupMembership";
+
+export interface GroupMembership {
+  groupId: string;
+  groupName: string;
+  username: string;
+  joinToken?: string;
+}
+
+export interface GroupDailyStatus {
+  groupId: string;
+  groupName: string;
+  currentStreak: number;
+  finishedUsers: string[];
+}
+
+export type GroupStatusMode = "daily" | "dailyMV";
+
+export function getStoredGroupMembership(): GroupMembership | null {
+  const raw = localStorage.getItem(GROUP_MEMBERSHIP_STORAGE_KEY);
+  if (!raw) return null;
+
+  try {
+    const parsed = JSON.parse(raw) as Partial<GroupMembership>;
+    if (
+      typeof parsed.groupId !== "string" ||
+      typeof parsed.groupName !== "string" ||
+      typeof parsed.username !== "string"
+    ) {
+      localStorage.removeItem(GROUP_MEMBERSHIP_STORAGE_KEY);
+      return null;
+    }
+
+    return {
+      groupId: parsed.groupId,
+      groupName: parsed.groupName,
+      username: parsed.username,
+      joinToken: typeof parsed.joinToken === "string" ? parsed.joinToken : undefined,
+    };
+  } catch {
+    localStorage.removeItem(GROUP_MEMBERSHIP_STORAGE_KEY);
+    return null;
+  }
+}
+
+export function saveGroupMembership(membership: GroupMembership) {
+  localStorage.setItem(GROUP_MEMBERSHIP_STORAGE_KEY, JSON.stringify(membership));
+}
+
+export async function createGroup(
+  name: string,
+  username: string
+): Promise<GroupMembership> {
+  const response = await fetch(`${API_URL}/create-group`, {
+    method: "POST",
+    headers: {
+      "Content-Type": "application/json",
+    },
+    body: JSON.stringify({ name, username }),
+  });
+
+  if (!response.ok) {
+    const fallback = `Failed to create group: ${response.statusText}`;
+    try {
+      const payload = (await response.json()) as { error?: unknown };
+      throw new Error(typeof payload.error === "string" ? payload.error : fallback);
+    } catch {
+      throw new Error(fallback);
+    }
+  }
+
+  const payload = (await response.json()) as {
+    group: {
+      id: string;
+      name: string;
+      joinToken: string;
+    };
+  };
+
+  return {
+    groupId: payload.group.id,
+    groupName: payload.group.name,
+    username,
+    joinToken: payload.group.joinToken,
+  };
+}
+
+export async function joinGroupByToken(
+  joinToken: string,
+  username: string
+): Promise<GroupMembership> {
+  const response = await fetch(`${API_URL}/join-group`, {
+    method: "POST",
+    headers: {
+      "Content-Type": "application/json",
+    },
+    body: JSON.stringify({ joinToken, username }),
+  });
+
+  if (!response.ok) {
+    const fallback = `Failed to join group: ${response.statusText}`;
+    try {
+      const payload = (await response.json()) as { error?: unknown };
+      throw new Error(typeof payload.error === "string" ? payload.error : fallback);
+    } catch {
+      throw new Error(fallback);
+    }
+  }
+
+  const payload = (await response.json()) as {
+    groupId: string;
+    groupName: string;
+    username: string;
+    joinToken: string;
+  };
+
+  return {
+    groupId: payload.groupId,
+    groupName: payload.groupName,
+    username: payload.username,
+    joinToken: payload.joinToken,
+  };
+}
+
+export async function getGroupDailyStatus(
+  groupId: string,
+  date: string,
+  mode: GroupStatusMode = "daily"
+): Promise<GroupDailyStatus> {
+  const response = await fetch(
+    `${API_URL}/group-status?groupId=${encodeURIComponent(groupId)}&date=${encodeURIComponent(date)}&mode=${encodeURIComponent(mode)}`
+  );
+
+  if (!response.ok) {
+    throw new Error(`Failed to fetch group status: ${response.statusText}`);
+  }
+
+  return (await response.json()) as GroupDailyStatus;
+}