add proposal

.gitignore

@@ -1 +1,3 @@
-node_modules/
+node_modules
+dist
+.DS_Store

MVP_PLAN.md

@@ -0,0 +1,310 @@
+# Minimal MVP Plan: P2P Poll App
+
+## Recommendation
+
+Build the MVP with:
+
+- Vanilla JS or TypeScript
+- Vite for local dev/build
+- Yjs for shared state
+- `y-webrtc` for browser-to-browser sync
+- `y-indexeddb` for local persistence/offline recovery
+
+This is the best fit for a small poll app because the data model is tiny, concurrent edits are possible, and Yjs already solves merge/conflict handling while `y-webrtc` gives a direct P2P transport with only signaling infrastructure.
+
+## Why This Stack
+
+### Recommended: Yjs + y-webrtc
+
+- Best balance of simplicity and correctness
+- Clients connect directly over WebRTC
+- No custom conflict-resolution logic needed
+- Easy to add offline persistence
+- Good fit for a single shared document/room
+
+### Not recommended for the first MVP
+
+#### PeerJS
+
+- Very simple transport layer
+- But you must design and maintain your own replication and merge rules
+- Fine for demos with a host-authoritative peer, weaker for true collaborative editing
+
+#### GUN
+
+- Fast to prototype realtime shared state
+- But official tutorials commonly use a GUN peer/relay server for shared data
+- For this app, its data model is less explicit than a CRDT and gives less control over vote semantics
+
+#### Automerge
+
+- Very capable CRDT and local-first model
+- But heavier than needed for a single small poll
+- Better choice if the project is expected to evolve into a richer collaborative app
+
+## MVP Scope
+
+Ship exactly one shared poll per room.
+
+Included:
+
+- Join a poll by opening a shared URL
+- Add a new option
+- Vote for one option
+- Change your vote
+- Realtime updates across peers
+- Local persistence in the browser
+- Basic connection status UI
+
+Excluded:
+
+- User accounts
+- Multiple polls per room
+- Option deletion/editing
+- Authentication/authorization
+- Rich presence
+- Advanced discovery
+- Production-grade TURN/signaling deployment
+
+## MVP UX
+
+Keep the interface intentionally small:
+
+- Poll title at the top
+- Option list with vote counts
+- One button per option to cast vote
+- Small form to add an option
+- Status line showing `connecting`, `connected`, or `offline`
+- Small label showing which option you voted for
+
+Join model:
+
+- Room ID in the URL, e.g. `/?room=poll-demo`
+- Users share the URL manually
+
+Identity model:
+
+- Generate a local `userId` once and store it in `localStorage`
+- Optional local display name, also stored locally
+
+## Shared Data Model
+
+Use a single Yjs document per room.
+
+Suggested structure:
+
+- `poll` as a `Y.Map`
+- `poll.title` as a string
+- `poll.options` as a `Y.Map<optionId, Y.Map>`
+- `poll.votes` as a `Y.Map<userId, optionId>`
+
+Each option record:
+
+- `id`
+- `label`
+- `createdBy`
+- `createdAt`
+
+Important design choice:
+
+Do not store vote counters as mutable shared numbers for the MVP.
+Instead, derive counts from `votes`.
+
+Why:
+
+- A user changing vote becomes a single write: `votes[userId] = optionId`
+- No double-counting logic
+- Concurrent writes are easier to reason about
+- Rendering counts from `votes` is trivial at this scale
+
+## Sync Model
+
+### Networking
+
+- Use `WebrtcProvider(roomId, ydoc)`
+- Start with the default public signaling servers for local development
+- If needed, swap to a self-hosted signaling server later without changing the app model
+
+### Persistence
+
+- Use `IndexeddbPersistence(roomId, ydoc)`
+- This preserves state across reloads and helps when reconnecting after temporary disconnects
+
+### Conflict behavior
+
+- Concurrent option additions merge naturally
+- Concurrent vote changes resolve at the per-user key level
+- Tally is recalculated from the merged vote map
+
+## Suggested Project Structure
+
+```text
+src/
+  main.ts
+  app.ts
+  state.ts
+  sync.ts
+  render.ts
+  identity.ts
+  styles.css
+index.html
+```
+
+Responsibilities:
+
+- `sync.ts`: create Yjs doc, WebRTC provider, IndexedDB provider
+- `state.ts`: shared structures, add option, cast vote, selectors
+- `identity.ts`: local `userId` and optional name
+- `render.ts`: DOM updates
+- `app.ts`: wire events to state and rendering
+
+## Implementation Plan
+
+### Phase 1: App shell
+
+- Create Vite app with vanilla TS or JS
+- Add a minimal single-page UI
+- Parse `room` from the URL
+- Generate and persist `userId`
+
+Success check:
+
+- App loads
+- Room ID appears in UI
+- User can type in the form
+
+### Phase 2: Shared state
+
+- Add Yjs document
+- Create root shared maps
+- Seed default poll title if missing
+- Observe document updates and re-render UI
+
+Success check:
+
+- State exists in one browser tab
+- Refresh keeps local state when IndexedDB is enabled
+
+### Phase 3: P2P sync
+
+- Add `y-webrtc`
+- Join room based on URL room ID
+- Show connection status from provider events
+
+Success check:
+
+- Two browsers on different tabs/devices see the same options
+- New options appear in near real time
+
+### Phase 4: Voting logic
+
+- Implement `castVote(optionId)` as `votes.set(userId, optionId)`
+- Derive tallies from `votes`
+- Highlight the local user’s current vote
+
+Success check:
+
+- Votes update live across peers
+- Changing vote updates counts correctly
+
+### Phase 5: Basic hardening
+
+- Trim/validate option labels
+- Prevent empty options
+- Ignore duplicate labels case-insensitively for MVP
+- Show simple offline/connecting text
+
+Success check:
+
+- Basic misuse does not break the UI
+- Reconnect restores updates
+
+## Minimal API Surface
+
+These functions are enough for the first build:
+
+- `getRoomId(): string`
+- `getUserId(): string`
+- `initSync(roomId): AppSync`
+- `ensurePollInitialized()`
+- `addOption(label: string)`
+- `castVote(optionId: string)`
+- `getViewModel(): PollViewModel`
+- `render(viewModel)`
+
+## Risks And MVP Mitigations
+
+### NAT / WebRTC connectivity
+
+Risk:
+
+- Some peer pairs may fail to connect in restrictive networks
+
+Mitigation:
+
+- Accept this for MVP
+- Keep signaling configurable
+- Add TURN only if testing shows frequent failures
+
+### Small public signaling dependency
+
+Risk:
+
+- Public signaling is fine for demos, not ideal for production
+
+Mitigation:
+
+- Treat it as replaceable infrastructure
+- Self-host later if the prototype is kept
+
+### Duplicate or messy options
+
+Risk:
+
+- Users may add near-duplicate entries
+
+Mitigation:
+
+- Normalize labels
+- Prevent exact duplicates for MVP
+
+### No trust/auth model
+
+Risk:
+
+- Any participant in the room can add options and vote
+
+Mitigation:
+
+- Accept for MVP
+- Frame rooms as small trusted groups
+
+## Estimated MVP Size
+
+For one developer:
+
+- Initial prototype: 0.5 to 1 day
+- Polished MVP with basic resilience: 1 to 2 days
+
+Rough code size:
+
+- 250 to 500 lines plus styles
+
+## Nice Next Steps After MVP
+
+- Copy-link button
+- Participant list / presence
+- Vote limit modes: single-choice or multi-choice
+- Option editing/deletion
+- QR code for room join
+- Self-hosted signaling server
+- PWA packaging for better offline behavior
+
+## Sources
+
+- PeerJS getting started: https://peerjs.com/client/getting-started
+- Yjs collaborative editor guide: https://docs.yjs.dev/getting-started/a-collaborative-editor
+- Yjs offline support: https://docs.yjs.dev/getting-started/allowing-offline-editing
+- y-webrtc README: https://github.com/yjs/y-webrtc
+- GUN tutorial showing shared data via a GUN peer: https://gun.eco/converse
+- Automerge network sync: https://automerge.org/docs/tutorial/network-sync/

README.md

@@ -1,55 +1,39 @@
 # P2P Poll App
 
-A peer-to-peer polling app built with [Automerge](https://automerge.org/) and Vanilla JS. No backend required — polls sync in real time across browsers using CRDTs and a WebSocket relay.
+Small peer-to-peer polling app built with `Vite`, `TypeScript`, `Yjs`, `y-webrtc`, and `y-indexeddb`.
 
 ## Features
 
-- **Add options** — type an option and press Enter or click "Add Option". Duplicate options (case-insensitive) are rejected with an inline error message.
-- **Vote on options** — click the vote button next to any option. You can vote on multiple options, but only once per option.
-- **Toggle votes** — click your vote again to remove it (the button turns green with a checkmark when you've voted).
-- **Live vote counts** — options are sorted by vote count in descending order and update in real time as votes come in from other users.
-- **2-minute countdown timer** — click "Start 2-min Vote" to begin a shared countdown. Voting is open before and during the countdown. Once the timer expires, all vote buttons are disabled.
-- **Shared timer** — the deadline is stored in the Automerge document, so all peers see the same countdown and voting closes simultaneously for everyone.
-- **Copy URL** — click "Copy URL" to copy the poll link to your clipboard. Share it with others to join the same poll.
-- **P2P sync** — all state (options, votes, timer) syncs across browsers in real time with no central server handling your data.
+- single shared poll per room
+- add options collaboratively
+- one vote per user, changeable at any time
+- peer-to-peer sync over WebRTC
+- local browser persistence for refresh/reconnect recovery
+- shareable room URL
 
-## How it works
-
-### Tech stack
-
-- **[Automerge](https://automerge.org/)** via `@automerge/vanillajs` — a CRDT library that lets multiple clients concurrently edit shared documents and merge changes without conflicts.
-- **BroadcastChannelNetworkAdapter** — syncs between tabs in the same browser instantly via the browser's BroadcastChannel API.
-- **WebSocketClientAdapter** — syncs across different browsers/devices via a WebSocket relay (`wss://sync.automerge.org`). The relay only forwards CRDT messages; it does not store or interpret your data.
-- **IndexedDBStorageAdapter** — persists the document locally so it survives page refreshes.
-- **Vite** — bundles the app with WebAssembly support (required by Automerge).
-
-### Data model
-
-The poll is a single Automerge document with three fields:
-
-```js
-{
-  options: string[],       // list of poll options in insertion order
-  votes: { [option]: number }, // vote count per option
-  deadline: number | null  // Unix timestamp (ms) when voting closes, or null
-}
-```
-
-### URL-based sharing
-
-Each document gets a unique Automerge URL (e.g. `automerge:abc123...`) stored in the page's URL hash. Opening the same URL in any browser loads and syncs the same document. Creating a new poll generates a new document and updates the hash automatically.
-
-### Voting rules
-
-- Voted options are tracked in `localStorage` (keyed by document URL), so they persist across page refreshes but are isolated per browser.
-- One vote per option per user. Votes can be toggled off and back on until the timer expires.
-- The timer (`doc.deadline`) is set once by whoever clicks "Start 2-min Vote" and is shared via the Automerge document, so all peers use the same deadline.
-
-## Running locally
+## Run locally
 
 ```bash
-pnpm install
-pnpm dev
+npm install
+npm run dev
 ```
 
-Open the printed localhost URL. To test cross-browser sync, copy the URL (including the `#automerge:...` hash) and open it in a different browser.
+Open the local URL in two tabs or browsers and use the same `?room=` query string to join the same poll.
+
+Example:
+
+```text
+http://localhost:5173/?room=poll-demo
+```
+
+## Build
+
+```bash
+npm run build
+```
+
+## Notes
+
+- The app uses public signaling through `y-webrtc` for MVP simplicity.
+- Poll state is not stored on an application server.
+- WebRTC connectivity can still depend on the network environment of the participating peers.

app.js

@@ -1,214 +0,0 @@
-import {
-  Repo,
-  BroadcastChannelNetworkAdapter,
-  WebSocketClientAdapter,
-  IndexedDBStorageAdapter,
-  isValidAutomergeUrl,
-} from "@automerge/vanillajs";
-
-const REPO = new Repo({
-  network: [
-    new BroadcastChannelNetworkAdapter(),
-    new WebSocketClientAdapter("wss://sync.automerge.org"),
-  ],
-  storage: new IndexedDBStorageAdapter(),
-});
-
-let HANDLE;
-
-function getVotedKey(docUrl) {
-  return `p2p-poll-voted:${docUrl}`;
-}
-
-function getVotedOptions() {
-  const key = getVotedKey(document.location.hash);
-  return new Set(JSON.parse(localStorage.getItem(key) || "[]"));
-}
-
-function markVoted(opt) {
-  const key = getVotedKey(document.location.hash);
-  const voted = getVotedOptions();
-  voted.add(opt);
-  localStorage.setItem(key, JSON.stringify([...voted]));
-}
-
-function unmarkVoted(opt) {
-  const key = getVotedKey(document.location.hash);
-  const voted = getVotedOptions();
-  voted.delete(opt);
-  localStorage.setItem(key, JSON.stringify([...voted]));
-}
-
-const locationHash = document.location.hash.substring(1);
-const statusEl = document.getElementById("status");
-const optionsList = document.getElementById("options-list");
-const optionInput = document.getElementById("option-input");
-const addBtn = document.getElementById("add-btn");
-const duplicateMsg = document.getElementById("duplicate-msg");
-const copyBtn = document.getElementById("copy-btn");
-const timerEl = document.getElementById("timer");
-const startVotingBtn = document.getElementById("start-voting-btn");
-
-if (isValidAutomergeUrl(locationHash)) {
-  statusEl.textContent = "Loading document…";
-  try {
-    HANDLE = await REPO.find(locationHash);
-    statusEl.textContent = "";
-  } catch (err) {
-    statusEl.textContent = "Could not load document. Starting a new one.";
-    HANDLE = REPO.create({ options: [], votes: {}, deadline: null });
-    document.location.hash = HANDLE.url;
-  }
-} else {
-  HANDLE = REPO.create({ options: [], votes: {}, deadline: null });
-  document.location.hash = HANDLE.url;
-}
-
-HANDLE.on("change", ({ doc }) => render(doc));
-
-const initialDoc = HANDLE.doc();
-if (initialDoc) render(initialDoc);
-
-let timerInterval = null;
-
-function render(doc) {
-  renderOptions(doc);
-  renderTimer(doc);
-}
-
-function renderOptions(doc) {
-  const votes = doc.votes || {};
-  const deadline = doc.deadline ?? null;
-  const now = Date.now();
-  const votingClosed = deadline !== null && now >= deadline;
-  const votedOptions = getVotedOptions();
-
-  const sorted = [...(doc.options || [])].sort(
-    (a, b) => (votes[b] || 0) - (votes[a] || 0),
-  );
-
-  optionsList.innerHTML = "";
-  sorted.forEach((opt) => {
-    const count = votes[opt] || 0;
-    const alreadyVoted = votedOptions.has(opt);
-
-    const item = document.createElement("div");
-    item.className = "option-item";
-
-    const label = document.createElement("span");
-    label.className = "option-label";
-    label.textContent = opt;
-
-    const voteBtn = document.createElement("button");
-    voteBtn.className = alreadyVoted ? "vote-btn voted" : "vote-btn";
-    voteBtn.textContent = alreadyVoted ? `✓ ${count}` : `▲ ${count}`;
-    voteBtn.disabled = votingClosed;
-    if (votingClosed) voteBtn.title = "Voting is closed";
-    else if (alreadyVoted) voteBtn.title = "Click to remove your vote";
-
-    voteBtn.addEventListener("click", () => {
-      if (alreadyVoted) {
-        unmarkVoted(opt);
-        HANDLE.change((d) => {
-          if (!d.votes) d.votes = {};
-          d.votes[opt] = Math.max(0, (d.votes[opt] || 0) - 1);
-        });
-      } else {
-        markVoted(opt);
-        HANDLE.change((d) => {
-          if (!d.votes) d.votes = {};
-          d.votes[opt] = (d.votes[opt] || 0) + 1;
-        });
-      }
-    });
-
-    item.appendChild(label);
-    item.appendChild(voteBtn);
-    optionsList.appendChild(item);
-  });
-}
-
-function renderTimer(doc) {
-  const deadline = doc?.deadline ?? null;
-  const now = Date.now();
-
-  if (deadline === null) {
-    timerEl.textContent = "";
-    startVotingBtn.hidden = false;
-    return;
-  }
-
-  startVotingBtn.hidden = true;
-
-  if (now >= deadline) {
-    timerEl.textContent = "Voting closed.";
-    timerEl.className = "timer closed";
-    clearInterval(timerInterval);
-    timerInterval = null;
-    return;
-  }
-
-  const remaining = Math.ceil((deadline - now) / 1000);
-  const mins = Math.floor(remaining / 60);
-  const secs = remaining % 60;
-  timerEl.textContent = `Voting closes in ${mins}:${secs.toString().padStart(2, "0")}`;
-  timerEl.className = "timer active";
-
-  if (!timerInterval) {
-    timerInterval = setInterval(() => {
-      const d = HANDLE.doc();
-      if (!d) return;
-      renderTimer(d);
-      renderOptions(d);
-      if (Date.now() >= d.deadline) {
-        clearInterval(timerInterval);
-        timerInterval = null;
-      }
-    }, 1000);
-  }
-}
-
-startVotingBtn.addEventListener("click", () => {
-  HANDLE.change((d) => {
-    d.deadline = Date.now() + 2 * 60 * 1000;
-  });
-});
-
-addBtn.addEventListener("click", () => {
-  const value = optionInput.value.trim();
-  if (!value) return;
-
-  const doc = HANDLE.doc();
-  const valueLower = value.toLowerCase();
-  const isDuplicate = (doc?.options || []).some(
-    (opt) => opt.toLowerCase() === valueLower,
-  );
-
-  if (isDuplicate) {
-    duplicateMsg.textContent = `"${value}" is already in the list.`;
-    duplicateMsg.hidden = false;
-    return;
-  }
-
-  duplicateMsg.hidden = true;
-  HANDLE.change((d) => {
-    if (!d.options) d.options = [];
-    d.options.push(value);
-  });
-  optionInput.value = "";
-});
-
-optionInput.addEventListener("keydown", (e) => {
-  if (e.key === "Enter") addBtn.click();
-});
-
-optionInput.addEventListener("input", () => {
-  duplicateMsg.hidden = true;
-});
-
-copyBtn.addEventListener("click", () => {
-  navigator.clipboard.writeText(window.location.href).then(() => {
-    copyBtn.textContent = "Copied!";
-    setTimeout(() => (copyBtn.textContent = "Copy URL"), 1500);
-  });
-});

index.html

@@ -3,29 +3,10 @@
   <head>
     <meta charset="UTF-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-        <title>P2P Polling App</title>
-        <link rel="stylesheet" href="./styles.css" />
+    <title>P2P Poll</title>
   </head>
   <body>
-        <div id="app">
-            <h1>P2P Polling App</h1>
-            <div id="status"></div>
-            <div id="add-option">
-                <input
-                    type="text"
-                    id="option-input"
-                    placeholder="Enter an option..."
-                />
-                <button id="add-btn">Add Option</button>
-            </div>
-            <div id="duplicate-msg" hidden></div>
-            <div id="timer-section">
-                <div id="timer"></div>
-                <button id="start-voting-btn">Start 2-min Vote</button>
-            </div>
-            <div id="options-list"></div>
-            <button id="copy-btn">Copy URL</button>
-        </div>
-        <script type="module" src="./app.js"></script>
+    <div id="app"></div>
+    <script type="module" src="/src/main.ts"></script>
   </body>
 </html>

package.json

@@ -1,23 +1,20 @@
 {
   "name": "p2p-poll-app",
+  "version": "0.1.0",
+  "private": true,
   "type": "module",
-  "engines": {
-    "node": ">=24"
-  },
   "scripts": {
     "dev": "vite",
-    "build": "vite build",
+    "build": "tsc --noEmit && vite build",
     "preview": "vite preview"
   },
   "dependencies": {
-    "@automerge/automerge-repo": "^2.0.0",
-    "@automerge/automerge-repo-network-websocket": "^2.0.0",
-    "@automerge/automerge-repo-storage-indexeddb": "^2.0.0",
-    "@automerge/vanillajs": "^2.5.3"
+    "y-indexeddb": "^9.0.12",
+    "y-webrtc": "^10.3.0",
+    "yjs": "^13.6.27"
   },
   "devDependencies": {
-    "vite": "^6.0.0",
-    "vite-plugin-top-level-await": "^1.4.0",
-    "vite-plugin-wasm": "^3.3.0"
+    "typescript": "^5.9.2",
+    "vite": "^7.1.5"
   }
 }

src/app.ts

@@ -0,0 +1,107 @@
+import { getUserId } from "./identity";
+import { renderApp } from "./render";
+import { addOption, castVote, createViewModel } from "./state";
+import { initSync } from "./sync";
+
+const ROOM_PARAM = "room";
+
+function createRoomId() {
+  const seed = typeof crypto.randomUUID === "function"
+    ? crypto.randomUUID().slice(0, 8)
+    : Math.random().toString(36).slice(2, 10);
+
+  return `poll-${seed}`;
+}
+
+function ensureRoomId() {
+  const url = new URL(window.location.href);
+  let roomId = url.searchParams.get(ROOM_PARAM)?.trim();
+
+  if (!roomId) {
+    roomId = createRoomId();
+    url.searchParams.set(ROOM_PARAM, roomId);
+    window.history.replaceState({}, "", url);
+  }
+
+  return roomId;
+}
+
+export function initApp(container: HTMLElement) {
+  const roomId = ensureRoomId();
+  const userId = getUserId();
+  const sync = initSync(roomId);
+  let feedbackMessage = "Ready to collaborate.";
+  let feedbackTimer: number | undefined;
+
+  const setFeedbackMessage = (message: string) => {
+    feedbackMessage = message;
+    render();
+
+    if (feedbackTimer) {
+      window.clearTimeout(feedbackTimer);
+    }
+
+    feedbackTimer = window.setTimeout(() => {
+      feedbackMessage = "Ready to collaborate.";
+      render();
+    }, 2400);
+  };
+
+  const render = () => {
+    const viewModel = createViewModel({
+      meta: sync.meta,
+      options: sync.options,
+      votes: sync.votes,
+      roomId,
+      shareUrl: window.location.href,
+      connectionStatus: sync.getConnectionStatus(),
+      userId,
+    });
+
+    renderApp(container, viewModel, feedbackMessage, {
+      onSubmitOption: (label) => {
+        const result = addOption(sync.options, label, userId);
+        if (!result.ok) {
+          setFeedbackMessage(result.error);
+          return;
+        }
+
+        setFeedbackMessage("Option added and syncing.");
+      },
+      onVote: (optionId) => {
+        castVote(sync.votes, userId, optionId);
+        setFeedbackMessage("Vote updated.");
+      },
+      onCopyLink: async () => {
+        try {
+          await navigator.clipboard.writeText(window.location.href);
+          setFeedbackMessage("Room link copied.");
+        } catch {
+          setFeedbackMessage("Could not copy the link in this browser.");
+        }
+      },
+    });
+  };
+
+  const rerender = () => render();
+  const observe = () => rerender();
+
+  sync.doc.on("update", observe);
+  sync.persistence.once("synced", rerender);
+  sync.provider.on("status", rerender);
+  window.addEventListener("online", rerender);
+  window.addEventListener("offline", rerender);
+
+  render();
+
+  return () => {
+    if (feedbackTimer) {
+      window.clearTimeout(feedbackTimer);
+    }
+    sync.doc.off("update", observe);
+    sync.provider.off("status", rerender);
+    window.removeEventListener("online", rerender);
+    window.removeEventListener("offline", rerender);
+    sync.destroy();
+  };
+}

src/identity.ts

@@ -0,0 +1,20 @@
+const USER_ID_KEY = "p2p-poll:user-id";
+
+function createUserId() {
+  if (typeof crypto.randomUUID === "function") {
+    return crypto.randomUUID();
+  }
+
+  return `user-${Math.random().toString(36).slice(2, 10)}`;
+}
+
+export function getUserId() {
+  const existing = localStorage.getItem(USER_ID_KEY);
+  if (existing) {
+    return existing;
+  }
+
+  const next = createUserId();
+  localStorage.setItem(USER_ID_KEY, next);
+  return next;
+}

src/main.ts

@@ -0,0 +1,11 @@
+import "./styles.css";
+
+import { initApp } from "./app";
+
+const container = document.querySelector<HTMLElement>("#app");
+
+if (!container) {
+  throw new Error("App container not found.");
+}
+
+initApp(container);

src/render.ts

@@ -0,0 +1,131 @@
+import type { PollViewModel } from "./state";
+
+interface RenderActions {
+  onSubmitOption: (label: string) => void;
+  onVote: (optionId: string) => void;
+  onCopyLink: () => void;
+}
+
+function escapeHtml(value: string) {
+  return value
+    .replaceAll("&", "&")
+    .replaceAll("<", "&lt;")
+    .replaceAll(">", "&gt;")
+    .replaceAll('"', "&quot;")
+    .replaceAll("'", "&#39;");
+}
+
+export function renderApp(
+  container: HTMLElement,
+  viewModel: PollViewModel,
+  feedbackMessage: string,
+  actions: RenderActions,
+) {
+  const optionMarkup = viewModel.options.length
+    ? viewModel.options
+        .map((option) => {
+          const buttonLabel = option.isSelectedByMe ? "Selected" : "Vote";
+          const selectedClass = option.isSelectedByMe ? "option-card selected" : "option-card";
+
+          return `
+            <li class="${selectedClass}">
+              <div class="option-main">
+                <div>
+                  <p class="option-label">${escapeHtml(option.label)}</p>
+                  <p class="option-meta">${option.voteCount} vote${option.voteCount === 1 ? "" : "s"}</p>
+                </div>
+                <button class="vote-button" data-option-id="${option.id}">
+                  ${buttonLabel}
+                </button>
+              </div>
+            </li>
+          `;
+        })
+        .join("")
+    : `
+      <li class="empty-state">
+        No options yet. Add the first one and it will sync to everyone in this room.
+      </li>
+    `;
+
+  const statusClass = `status-pill ${viewModel.connectionStatus}`;
+  const myVoteLabel = viewModel.myVoteOptionId
+    ? "Your vote is currently synced."
+    : "You have not voted yet.";
+
+  container.innerHTML = `
+    <main class="shell">
+      <section class="hero">
+        <div class="hero-copy">
+          <p class="eyebrow">Peer-to-peer room</p>
+          <h1>${escapeHtml(viewModel.title)}</h1>
+          <p class="hero-text">
+            Share the room link, add options, and vote live without a central app server storing poll state.
+          </p>
+        </div>
+        <div class="hero-meta">
+          <span class="${statusClass}">${viewModel.connectionStatus}</span>
+          <p class="room-label">Room: <code>${escapeHtml(viewModel.roomId)}</code></p>
+        </div>
+      </section>
+
+      <section class="panel share-panel">
+        <label class="field-label" for="share-url">Share this room</label>
+        <div class="share-row">
+          <input id="share-url" class="share-input" type="text" readonly value="${escapeHtml(viewModel.shareUrl)}" />
+          <button id="copy-link-button" class="secondary-button" type="button">Copy link</button>
+        </div>
+      </section>
+
+      <section class="panel">
+        <div class="section-header">
+          <div>
+            <h2>Options</h2>
+            <p>${myVoteLabel}</p>
+          </div>
+        </div>
+        <ul class="options-list">${optionMarkup}</ul>
+      </section>
+
+      <section class="panel">
+        <h2>Add an option</h2>
+        <form id="add-option-form" class="option-form">
+          <input
+            id="option-input"
+            name="option"
+            type="text"
+            maxlength="80"
+            placeholder="Add an option"
+            autocomplete="off"
+            required
+          />
+          <button class="primary-button" type="submit">Add option</button>
+        </form>
+        <p class="feedback" aria-live="polite">${escapeHtml(feedbackMessage)}</p>
+      </section>
+    </main>
+  `;
+
+  const addOptionForm = container.querySelector<HTMLFormElement>("#add-option-form");
+  const optionInput = container.querySelector<HTMLInputElement>("#option-input");
+  const copyLinkButton = container.querySelector<HTMLButtonElement>("#copy-link-button");
+
+  addOptionForm?.addEventListener("submit", (event) => {
+    event.preventDefault();
+    const label = optionInput?.value ?? "";
+    actions.onSubmitOption(label);
+  });
+
+  copyLinkButton?.addEventListener("click", () => {
+    actions.onCopyLink();
+  });
+
+  container.querySelectorAll<HTMLButtonElement>("[data-option-id]").forEach((button) => {
+    button.addEventListener("click", () => {
+      const optionId = button.dataset.optionId;
+      if (optionId) {
+        actions.onVote(optionId);
+      }
+    });
+  });
+}

src/state.ts

@@ -0,0 +1,124 @@
+import * as Y from "yjs";
+
+export const DEFAULT_POLL_TITLE = "Shared Poll";
+
+export type ConnectionStatus = "connecting" | "connected" | "offline";
+
+export interface OptionRecord {
+  id: string;
+  label: string;
+  createdAt: number;
+  createdBy: string;
+}
+
+export interface PollOptionViewModel extends OptionRecord {
+  voteCount: number;
+  isSelectedByMe: boolean;
+}
+
+export interface PollViewModel {
+  title: string;
+  roomId: string;
+  shareUrl: string;
+  connectionStatus: ConnectionStatus;
+  options: PollOptionViewModel[];
+  myVoteOptionId: string | null;
+}
+
+const META_KEY_TITLE = "title";
+
+function createOptionId() {
+  if (typeof crypto.randomUUID === "function") {
+    return crypto.randomUUID();
+  }
+
+  return `option-${Math.random().toString(36).slice(2, 10)}`;
+}
+
+function normalizeLabel(label: string) {
+  return label.trim().replace(/\s+/g, " ");
+}
+
+function getPollTitle(meta: Y.Map<string>) {
+  return meta.get(META_KEY_TITLE) ?? DEFAULT_POLL_TITLE;
+}
+
+export function ensurePollInitialized(meta: Y.Map<string>) {
+  if (!meta.has(META_KEY_TITLE)) {
+    meta.set(META_KEY_TITLE, DEFAULT_POLL_TITLE);
+  }
+}
+
+export function addOption(
+  options: Y.Map<OptionRecord>,
+  rawLabel: string,
+  userId: string,
+) {
+  const label = normalizeLabel(rawLabel);
+  if (!label) {
+    return { ok: false as const, error: "Option label cannot be empty." };
+  }
+
+  const normalizedTarget = label.toLocaleLowerCase();
+  const duplicate = Array.from(options.values()).some(
+    (option) => option.label.trim().toLocaleLowerCase() === normalizedTarget,
+  );
+
+  if (duplicate) {
+    return { ok: false as const, error: "That option already exists." };
+  }
+
+  const option: OptionRecord = {
+    id: createOptionId(),
+    label,
+    createdAt: Date.now(),
+    createdBy: userId,
+  };
+
+  options.set(option.id, option);
+  return { ok: true as const, optionId: option.id };
+}
+
+export function castVote(votes: Y.Map<string>, userId: string, optionId: string) {
+  votes.set(userId, optionId);
+}
+
+export function createViewModel(params: {
+  meta: Y.Map<string>;
+  options: Y.Map<OptionRecord>;
+  votes: Y.Map<string>;
+  roomId: string;
+  shareUrl: string;
+  connectionStatus: ConnectionStatus;
+  userId: string;
+}): PollViewModel {
+  const { meta, options, votes, roomId, shareUrl, connectionStatus, userId } =
+    params;
+
+  const tally = new Map<string, number>();
+  for (const optionId of votes.values()) {
+    tally.set(optionId, (tally.get(optionId) ?? 0) + 1);
+  }
+
+  const myVoteOptionId = votes.get(userId) ?? null;
+  const sortedOptions = Array.from(options.values()).sort((left, right) => {
+    if (left.createdAt !== right.createdAt) {
+      return left.createdAt - right.createdAt;
+    }
+
+    return left.label.localeCompare(right.label);
+  });
+
+  return {
+    title: getPollTitle(meta),
+    roomId,
+    shareUrl,
+    connectionStatus,
+    myVoteOptionId,
+    options: sortedOptions.map((option) => ({
+      ...option,
+      voteCount: tally.get(option.id) ?? 0,
+      isSelectedByMe: myVoteOptionId === option.id,
+    })),
+  };
+}

src/styles.css

@@ -0,0 +1,256 @@
+:root {
+  font-family: "IBM Plex Sans", "Segoe UI", sans-serif;
+  color: #132238;
+  background:
+    radial-gradient(circle at top left, rgba(255, 190, 120, 0.55), transparent 28%),
+    radial-gradient(circle at top right, rgba(86, 201, 166, 0.3), transparent 24%),
+    linear-gradient(180deg, #f9f4e8 0%, #f4efe6 48%, #ece5d8 100%);
+  line-height: 1.5;
+  font-weight: 400;
+  color-scheme: light;
+}
+
+* {
+  box-sizing: border-box;
+}
+
+body {
+  margin: 0;
+  min-height: 100vh;
+}
+
+button,
+input {
+  font: inherit;
+}
+
+button {
+  cursor: pointer;
+}
+
+#app {
+  min-height: 100vh;
+}
+
+.shell {
+  width: min(920px, calc(100% - 2rem));
+  margin: 0 auto;
+  padding: 2rem 0 3rem;
+}
+
+.hero {
+  display: flex;
+  justify-content: space-between;
+  gap: 1.5rem;
+  align-items: flex-start;
+  margin-bottom: 1.5rem;
+}
+
+.hero-copy h1 {
+  margin: 0.15rem 0 0.5rem;
+  font-size: clamp(2.4rem, 6vw, 4rem);
+  line-height: 0.95;
+  letter-spacing: -0.05em;
+}
+
+.hero-text,
+.section-header p,
+.feedback,
+.option-meta,
+.room-label {
+  color: #4a5a6a;
+}
+
+.eyebrow {
+  margin: 0;
+  text-transform: uppercase;
+  letter-spacing: 0.16em;
+  font-size: 0.8rem;
+  color: #915f00;
+}
+
+.hero-meta {
+  min-width: 15rem;
+  padding: 1rem 1.1rem;
+  border-radius: 1.2rem;
+  background: rgba(255, 255, 255, 0.68);
+  border: 1px solid rgba(19, 34, 56, 0.08);
+  backdrop-filter: blur(10px);
+}
+
+.status-pill {
+  display: inline-flex;
+  align-items: center;
+  padding: 0.35rem 0.75rem;
+  border-radius: 999px;
+  font-weight: 700;
+  text-transform: capitalize;
+  font-size: 0.9rem;
+}
+
+.status-pill.connected {
+  background: rgba(86, 201, 166, 0.18);
+  color: #135d43;
+}
+
+.status-pill.connecting {
+  background: rgba(255, 190, 120, 0.22);
+  color: #8c5300;
+}
+
+.status-pill.offline {
+  background: rgba(219, 82, 82, 0.16);
+  color: #8f1f1f;
+}
+
+.panel {
+  margin-bottom: 1.25rem;
+  padding: 1.25rem;
+  border-radius: 1.3rem;
+  background: rgba(255, 255, 255, 0.78);
+  border: 1px solid rgba(19, 34, 56, 0.08);
+  box-shadow: 0 14px 40px rgba(19, 34, 56, 0.08);
+  backdrop-filter: blur(10px);
+}
+
+.panel h2 {
+  margin: 0 0 0.45rem;
+  font-size: 1.1rem;
+}
+
+.share-row,
+.option-form,
+.option-main {
+  display: flex;
+  gap: 0.75rem;
+}
+
+.field-label {
+  display: block;
+  margin-bottom: 0.6rem;
+  font-weight: 700;
+}
+
+.share-input,
+.option-form input {
+  width: 100%;
+  min-width: 0;
+  border-radius: 0.95rem;
+  border: 1px solid rgba(19, 34, 56, 0.14);
+  background: rgba(255, 255, 255, 0.94);
+  padding: 0.85rem 1rem;
+  color: #132238;
+}
+
+.share-input:focus,
+.option-form input:focus {
+  outline: 2px solid rgba(255, 190, 120, 0.65);
+  outline-offset: 1px;
+}
+
+.primary-button,
+.secondary-button,
+.vote-button {
+  border: none;
+  border-radius: 0.95rem;
+  padding: 0.85rem 1rem;
+  font-weight: 700;
+  transition: transform 150ms ease, box-shadow 150ms ease, background-color 150ms ease;
+}
+
+.primary-button,
+.vote-button {
+  background: #132238;
+  color: #f9f4e8;
+  box-shadow: 0 10px 20px rgba(19, 34, 56, 0.14);
+}
+
+.secondary-button {
+  background: rgba(19, 34, 56, 0.08);
+  color: #132238;
+}
+
+.primary-button:hover,
+.secondary-button:hover,
+.vote-button:hover {
+  transform: translateY(-1px);
+}
+
+.options-list {
+  list-style: none;
+  margin: 1rem 0 0;
+  padding: 0;
+  display: grid;
+  gap: 0.75rem;
+}
+
+.option-card,
+.empty-state {
+  border-radius: 1.1rem;
+  padding: 1rem;
+  background: rgba(247, 244, 236, 0.95);
+  border: 1px solid rgba(19, 34, 56, 0.08);
+}
+
+.option-card.selected {
+  border-color: rgba(86, 201, 166, 0.85);
+  background: rgba(232, 249, 242, 0.95);
+}
+
+.option-main {
+  align-items: center;
+  justify-content: space-between;
+}
+
+.option-label {
+  margin: 0;
+  font-size: 1.05rem;
+  font-weight: 700;
+}
+
+.option-meta,
+.feedback,
+.room-label {
+  margin: 0.35rem 0 0;
+}
+
+.section-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: baseline;
+  gap: 1rem;
+}
+
+.feedback {
+  min-height: 1.5rem;
+}
+
+code {
+  font-family: "IBM Plex Mono", "SFMono-Regular", monospace;
+}
+
+@media (max-width: 720px) {
+  .shell {
+    width: min(100% - 1rem, 920px);
+    padding-top: 1rem;
+  }
+
+  .hero,
+  .share-row,
+  .option-form,
+  .option-main,
+  .section-header {
+    flex-direction: column;
+  }
+
+  .hero-meta {
+    width: 100%;
+    min-width: 0;
+  }
+
+  .primary-button,
+  .secondary-button,
+  .vote-button {
+    width: 100%;
+  }
+}

src/sync.ts

@@ -0,0 +1,64 @@
+import { IndexeddbPersistence } from "y-indexeddb";
+import { WebrtcProvider } from "y-webrtc";
+import * as Y from "yjs";
+
+import { type ConnectionStatus, ensurePollInitialized, type OptionRecord } from "./state";
+
+export interface AppSync {
+  doc: Y.Doc;
+  meta: Y.Map<string>;
+  options: Y.Map<OptionRecord>;
+  votes: Y.Map<string>;
+  provider: WebrtcProvider;
+  persistence: IndexeddbPersistence;
+  getConnectionStatus: () => ConnectionStatus;
+  destroy: () => void;
+}
+
+export function initSync(roomId: string): AppSync {
+  const doc = new Y.Doc();
+  const meta = doc.getMap<string>("poll-meta");
+  const options = doc.getMap<OptionRecord>("poll-options");
+  const votes = doc.getMap<string>("poll-votes");
+
+  ensurePollInitialized(meta);
+
+  let connectionStatus: ConnectionStatus = navigator.onLine ? "connecting" : "offline";
+  const provider = new WebrtcProvider(roomId, doc);
+  const persistence = new IndexeddbPersistence(roomId, doc);
+
+  const syncConnectionStatus = (status: ConnectionStatus) => {
+    connectionStatus = navigator.onLine ? status : "offline";
+  };
+
+  const handleOnline = () => {
+    syncConnectionStatus(provider.connected ? "connected" : "connecting");
+  };
+  const handleOffline = () => {
+    connectionStatus = "offline";
+  };
+
+  provider.on("status", (event: { connected: boolean }) => {
+    syncConnectionStatus(event.connected ? "connected" : "connecting");
+  });
+
+  window.addEventListener("online", handleOnline);
+  window.addEventListener("offline", handleOffline);
+
+  return {
+    doc,
+    meta,
+    options,
+    votes,
+    provider,
+    persistence,
+    getConnectionStatus: () => connectionStatus,
+    destroy: () => {
+      window.removeEventListener("online", handleOnline);
+      window.removeEventListener("offline", handleOffline);
+      persistence.destroy();
+      provider.destroy();
+      doc.destroy();
+    },
+  };
+}

styles.css

@@ -1,93 +0,0 @@
-body {
-    font-family: sans-serif;
-    max-width: 480px;
-    margin: 40px auto;
-    padding: 0 16px;
-}
-
-#add-option {
-    display: flex;
-    gap: 8px;
-    margin-bottom: 8px;
-}
-
-#option-input {
-    flex: 1;
-    padding: 8px;
-    font-size: 1rem;
-    border: 1px solid #ccc;
-    border-radius: 4px;
-}
-
-#duplicate-msg {
-    color: #c00;
-    font-size: 0.9rem;
-    margin-bottom: 12px;
-}
-
-button {
-    padding: 8px 16px;
-    font-size: 1rem;
-    cursor: pointer;
-    border: 1px solid #ccc;
-    border-radius: 4px;
-    background: #fff;
-}
-
-button:hover:not(:disabled) {
-    background: #f0f0f0;
-}
-
-button:disabled {
-    opacity: 0.5;
-    cursor: default;
-}
-
-#timer-section {
-    display: flex;
-    align-items: center;
-    gap: 12px;
-    margin-bottom: 16px;
-}
-
-.timer.active {
-    font-weight: bold;
-    color: #1a6e1a;
-}
-
-.timer.closed {
-    font-weight: bold;
-    color: #c00;
-}
-
-.option-item {
-    display: flex;
-    align-items: center;
-    justify-content: space-between;
-    padding: 10px 12px;
-    border: 1px solid #ddd;
-    border-radius: 4px;
-    margin-bottom: 8px;
-}
-
-.option-label {
-    flex: 1;
-}
-
-.vote-btn {
-    padding: 4px 12px;
-    font-size: 0.9rem;
-    white-space: nowrap;
-}
-
-.vote-btn.voted {
-    background: #e6f4e6;
-    border-color: #4a9e4a;
-    color: #2a6e2a;
-}
-
-
-#copy-btn {
-    margin-top: 16px;
-    width: 100%;
-}

tsconfig.json

@@ -0,0 +1,15 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "module": "ESNext",
+    "moduleResolution": "Bundler",
+    "lib": ["DOM", "DOM.Iterable", "ES2022"],
+    "strict": true,
+    "noEmit": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "allowSyntheticDefaultImports": true,
+    "useDefineForClassFields": true
+  },
+  "include": ["src"]
+}

vite.config.js

@@ -1,7 +0,0 @@
-import { defineConfig } from 'vite'
-import wasm from 'vite-plugin-wasm'
-import topLevelAwait from 'vite-plugin-top-level-await'
-
-export default defineConfig({
-  plugins: [wasm(), topLevelAwait()]
-})