fix(vibenet): build Validity candles from chain data in the browser

app/vibenet/demos/validity/ValidityDemo.tsx

@@ -29,6 +29,7 @@ import {
   helperApproveCalls,
   inventoryMints,
   reservesFromSyncLog,
+  SYNC_EVENT,
   tokenBalance,
 } from './lib/amm';
 import {
@@ -65,16 +66,14 @@ import {
 } from './lib/quote';
 import {
   describeValidityError,
-  fetchTape,
   makePublicClient,
-  publishTape,
   sendValidityTransaction,
   VIBENET_CHAIN,
   type RpcSend,
 } from './lib/rpc';
 import { connectJsonRpcStream, headNumber, type StreamHead, type StreamLog } from './lib/stream';
 import { probeSingleton } from './lib/singleton';
-import { mergeTape } from './lib/tape';
+import { backfillBlocks, backfillSamples, mergeTape } from './lib/tape';
 import { createState, loadState, saveState, type StoredState } from './lib/store';
 import type { PlacedOrder, Rectangle, Reserves, Side } from './lib/types';
 
@@ -145,8 +144,6 @@ function ValidityDemoInner() {
   ordersRef.current = orders;
   const reservesRef = useRef<Reserves | null>(null);
   reservesRef.current = reserves;
-  const samplesRef = useRef<PriceSample[]>([]);
-  samplesRef.current = samples;
   const stateRef = useRef<StoredState | null>(null);
   stateRef.current = state;
 
@@ -195,38 +192,31 @@ function ValidityDemoInner() {
   const tapeVibeToken0 = Boolean(state?.deployment && vibeIsToken0(state.deployment));
 
   useEffect(() => {
-    if (!hydrated || !pair) return;
+    const client = publicRef.current;
+    if (!hydrated || !pair || !client) return;
     let cancelled = false;
-    void fetchTape(pair, tapeVibeToken0)
-      .then((remote) => {
-        if (cancelled || remote.length === 0) return;
-        setSamples((prev) => mergeTape(remote, prev));
-      })
-      .catch(() => {});
+    void (async () => {
+      const latestBlock = await client.getBlockNumber();
+      const lookback = backfillBlocks();
+      const [logs, current] = await Promise.all([
+        client.getLogs({
+          address: pair,
+          event: SYNC_EVENT,
+          fromBlock: latestBlock > lookback ? latestBlock - lookback : 0n,
+          toBlock: latestBlock,
+        }),
+        getReserves(client, pair),
+      ]);
+      if (cancelled) return;
+      const mid = Number(quoteWad(current.reserve0, current.reserve1, tapeVibeToken0)) / 1e18;
+      const history = backfillSamples({ logs, vibeToken0: tapeVibeToken0, latestBlock, now: Date.now(), mid });
+      setSamples((prev) => mergeTape(history, prev));
+    })().catch(() => {});
     return () => {
       cancelled = true;
     };
   }, [hydrated, pair, tapeVibeToken0]);
 
-  useEffect(() => {
-    if (!hydrated || !pair) return;
-    const flush = () => {
-      void publishTape(pair, samplesRef.current).catch(() => {});
-    };
-    const id = window.setInterval(flush, 2_000);
-    const onHide = () => {
-      if (document.visibilityState === 'hidden') flush();
-    };
-    document.addEventListener('visibilitychange', onHide);
-    window.addEventListener('pagehide', flush);
-    return () => {
-      window.clearInterval(id);
-      document.removeEventListener('visibilitychange', onHide);
-      window.removeEventListener('pagehide', flush);
-      flush();
-    };
-  }, [hydrated, pair]);
-
   useEffect(() => {
     let cancelled = false;
     const client = makePublicClient(() => rpcSendRef.current);

app/vibenet/demos/validity/components/PriceCandles.test.ts

@@ -6,7 +6,7 @@ import { isUpCandle, toCandles, type PriceSample } from './PriceCandles';
 const BUCKET = CANDLE_BUCKET_MS;
 
 describe('toCandles', () => {
-  it('builds a wick when 200ms prints reverse inside a 5s bucket', () => {
+  it('builds a wick when 200ms prints reverse inside a 1s bucket', () => {
     const t0 = 1_000_000;
     const samples: PriceSample[] = [
       { t: t0, price: 1.0 },
@@ -50,15 +50,15 @@ describe('toCandles', () => {
     expect(isUpCandle(candles[1], candles[0])).toBe(false);
   });
 
-  it('fills empty 5s buckets so a 15s gap does not leave a hole', () => {
+  it('fills empty 1s buckets so a 3s gap does not leave a hole', () => {
     const t0 = 3_000_000;
     const samples: PriceSample[] = [
       { t: t0, price: 0.07 },
-      { t: t0 + 15_000, price: 0.071 },
+      { t: t0 + 3 * BUCKET, price: 0.071 },
     ];
-    const candles = toCandles(samples, { now: t0 + 15_000, windowMs: 20_000 });
-    expect(candles.map((candle) => candle.t)).toEqual([t0, t0 + 5_000, t0 + 10_000, t0 + 15_000]);
-    expect(candles[1]).toEqual({ t: t0 + 5_000, o: 0.07, h: 0.07, l: 0.07, c: 0.07 });
+    const candles = toCandles(samples, { now: t0 + 3 * BUCKET, windowMs: 4 * BUCKET });
+    expect(candles.map((candle) => candle.t)).toEqual([t0, t0 + BUCKET, t0 + 2 * BUCKET, t0 + 3 * BUCKET]);
+    expect(candles[1]).toEqual({ t: t0 + BUCKET, o: 0.07, h: 0.07, l: 0.07, c: 0.07 });
     expect(candles[3].o).toBe(0.07);
     expect(candles[3].c).toBe(0.071);
   });

app/vibenet/demos/validity/components/PriceCandles.tsx

@@ -194,7 +194,7 @@ export function PriceCandles({ samples, levels = [], fills = [] }: Props) {
           <VibeMark />
           <div>
             <div className="font-mono text-[13px] tracking-[0.08em] text-foreground">VIBE / USDV</div>
-            <div className="font-mono text-[11px] text-bds-gray-50">simulated pool · 5s candles</div>
+            <div className="font-mono text-[11px] text-bds-gray-50">simulated pool · 1s candles</div>
           </div>
         </div>
         <div className="text-right">

app/vibenet/demos/validity/lib/amm.ts

@@ -1,4 +1,5 @@
 import {
+  encodeEventTopics,
   encodeFunctionData,
   parseAbi,
   parseEventLogs,
@@ -13,6 +14,9 @@ const pairEvents = parseAbi([
   'event Sync(uint112 reserve0, uint112 reserve1)',
 ]);
 
+export const SYNC_EVENT = pairEvents[1];
+export const SYNC_TOPIC = encodeEventTopics({ abi: pairEvents, eventName: 'Sync' })[0];
+
 import { QUOTE_SCALE, TRADER_USDV, TRADER_VIBE, erc20Abi, helperAbi, minterAbi, pairAbi } from './constants';
 import { sqrt } from './predicates';
 import { quoteFromPreSwapReserves } from './quote';

app/vibenet/demos/validity/lib/constants.ts

@@ -42,8 +42,6 @@ export const minterAbi = parseAbi([
   'function mint(address token, address to, uint256 amount)',
 ]);
 
-export const CANDLES_PATH = '/api/vibenet/validity/candles';
-
 export const STORAGE_KEY = 'vibenet.validity.v7';
 
 export const WAD = 10n ** 18n;
@@ -70,10 +68,11 @@ export const MAX_EXPIRY_SECONDS = 60;
  * are on committed 200ms blocks, not 2s pre-Denim heads or 250ms flashblocks.
  */
 export const BLOCK_SECONDS = 0.2;
-/** Stamp the mid on each 200ms head so the live 5s candle can wick. */
+/** Stamp the mid on each 200ms head so the live 1s candle can wick. */
 export const CANDLE_SAMPLE_MS = 200;
-export const CANDLE_BUCKET_MS = 5_000;
-export const CANDLE_WINDOW_MS = 180_000;
+export const CANDLE_BUCKET_MS = 1_000;
+export const CANDLE_WINDOW_MS = 30_000;
+export const CANDLE_BACKFILL_MS = 10_000;
 
 /**
  * Finite box span around the target point on the current hyperbola.

app/vibenet/demos/validity/lib/rpc.ts

@@ -12,8 +12,6 @@ import {
 
 import { VIBENET_RPC_URL, VIBENET_WS_URL } from '../../../library/config';
 import { VIBENET } from '../../account/library/chains';
-import { CANDLES_PATH } from './constants';
-import { parseTapeSamples, type TapeSample } from './tape';
 import type { ValidityPredicate } from './types';
 
 export type RpcSend = (method: string, params: unknown[]) => Promise<unknown>;
@@ -69,26 +67,6 @@ export function makeWalletClient(account: Account): WalletClient {
   return createWalletClient({ chain: VIBENET_CHAIN, account, transport: custom(eip1193()) });
 }
 
-export async function fetchTape(pair: Address, vibeToken0: boolean): Promise<TapeSample[]> {
-  const response = await fetch(
-    `${CANDLES_PATH}?pair=${pair}&vibeToken0=${vibeToken0 ? '1' : '0'}`,
-    { cache: 'no-store' },
-  );
-  if (!response.ok) return [];
-  const body = (await response.json().catch(() => null)) as { samples?: unknown } | null;
-  return parseTapeSamples(body?.samples);
-}
-
-export async function publishTape(pair: Address, samples: readonly TapeSample[]): Promise<void> {
-  if (samples.length === 0) return;
-  await fetch(CANDLES_PATH, {
-    method: 'POST',
-    headers: { 'Content-Type': 'application/json' },
-    body: JSON.stringify({ pair, samples }),
-    keepalive: true,
-  });
-}
-
 export function describeValidityError(err: unknown): string {
   const record = err as {
     shortMessage?: string;

app/vibenet/demos/validity/lib/singleton.test.ts

@@ -0,0 +1,18 @@
+import { describe, expect, it } from 'vitest';
+
+import { pickLivePair } from './singleton';
+
+describe('pickLivePair', () => {
+  it('follows the most recently traded seeded pool over an idle duplicate', () => {
+    const idle = { id: 'idle', reserve0: 1n, reserve1: 1n, lastTradeAt: 100 };
+    const live = { id: 'live', reserve0: 1n, reserve1: 1n, lastTradeAt: 900 };
+    expect(pickLivePair([idle, live])?.id).toBe('live');
+  });
+
+  it('skips unseeded pools', () => {
+    const empty = { id: 'empty', reserve0: 0n, reserve1: 5n, lastTradeAt: 999 };
+    const seeded = { id: 'seeded', reserve0: 1n, reserve1: 1n, lastTradeAt: 1 };
+    expect(pickLivePair([empty, seeded])?.id).toBe('seeded');
+    expect(pickLivePair([empty])).toBeNull();
+  });
+});