Add countdown timer for daily free market (#276)

* Add countdown timer for daily free market

* Reset example numbers

* Remove daily

* Free market reset => 4pm UTC

functions/src/create-contract.ts

@@ -87,13 +87,17 @@ export const createContract = newEndpoint(['POST'], async (req, _res) => {
   )
     throw new APIError(400, 'Invalid initial probability')
 
-  // uses utc time on server:
-  const today = new Date().setHours(0, 0, 0, 0)
+  // Uses utc time on server:
+  const yesterday = new Date()
+  yesterday.setUTCDate(yesterday.getUTCDate() - 1)
+  const freeMarketResetTime = yesterday.setUTCHours(16, 0, 0, 0)
+
   const userContractsCreatedTodaySnapshot = await firestore
     .collection(`contracts`)
     .where('creatorId', '==', creator.id)
-    .where('createdTime', '>=', today)
+    .where('createdTime', '>=', freeMarketResetTime)
     .get()
+  console.log('free market reset time: ', freeMarketResetTime)
   const isFree = userContractsCreatedTodaySnapshot.size === 0
 
   const ante = FIXED_ANTE

web/components/nav/sidebar.tsx

@@ -20,8 +20,12 @@ import { firebaseLogin, firebaseLogout } from 'web/lib/firebase/users'
 import { ManifoldLogo } from './manifold-logo'
 import { MenuButton } from './menu'
 import { getNavigationOptions, ProfileSummary } from './profile-menu'
-import { useHasCreatedContractToday } from 'web/hooks/use-has-created-contract-today'
+import {
+  getUtcFreeMarketResetTimeToday,
+  useHasCreatedContractToday,
+} from 'web/hooks/use-has-created-contract-today'
 import { Row } from '../layout/row'
+import { useEffect, useState } from 'react'
 
 // Create an icon from the url of an image
 function IconFromUrl(url: string): React.ComponentType<{ className?: string }> {
@@ -121,12 +125,30 @@ export default function Sidebar(props: { className?: string }) {
   const { className } = props
   const router = useRouter()
   const currentPage = router.pathname
+  const [countdown, setCountdown] = useState('...')
+  useEffect(() => {
+    const utcMidnightToLocalDate = new Date(getUtcFreeMarketResetTimeToday())
+    const interval = setInterval(() => {
+      const timeUntil = utcMidnightToLocalDate.getTime() - new Date().getTime()
+      const hoursUntil = 24 + timeUntil / 1000 / 60 / 60
+      const minutesUntil = Math.floor((hoursUntil * 60) % 60)
+      const secondsUntil = Math.floor((hoursUntil * 60 * 60) % 60)
+      const hoursUntilFloor = Math.floor(hoursUntil)
+      const timeString =
+        minutesUntil < 1
+          ? `${secondsUntil}s`
+          : hoursUntilFloor < 1
+          ? `${minutesUntil}m`
+          : `${hoursUntilFloor}h`
+      setCountdown(timeString)
+    }, 1000)
+    return () => clearInterval(interval)
+  }, [])
 
   const user = useUser()
   let folds = useFollowedFolds(user) || []
   folds = sortBy(folds, 'followCount').reverse()
-  const deservesDailyFreeMarket = !useHasCreatedContractToday(user)
-
+  const mustWaitForFreeMarketStatus = useHasCreatedContractToday(user)
   const navigationOptions =
     user === null
       ? signedOutNavigation
@@ -186,13 +208,25 @@ export default function Sidebar(props: { className?: string }) {
         )}
       </div>
 
-      {user && deservesDailyFreeMarket && (
+      {user &&
+      mustWaitForFreeMarketStatus != 'loading' &&
+      mustWaitForFreeMarketStatus ? (
+        <Row className="mt-2 justify-center">
+          <Row className="gap-1 text-sm text-gray-400">
+            Next free market in {countdown}
+          </Row>
+        </Row>
+      ) : (
+        user &&
+        mustWaitForFreeMarketStatus != 'loading' &&
+        !mustWaitForFreeMarketStatus && (
           <Row className="mt-2 justify-center">
             <Row className="gap-1 text-sm text-indigo-400">
               Daily free market
               <SparklesIcon className="mt-0.5 h-4 w-4" aria-hidden="true" />
             </Row>
           </Row>
+        )
       )}
     </nav>
   )

web/hooks/use-has-created-contract-today.ts

@@ -4,16 +4,22 @@ import { User } from 'common/user'
 
 let sessionCreatedContractToday = true
 
+export function getUtcFreeMarketResetTimeToday() {
+  // Uses utc time like the server.
+  const utcFreeMarketResetTime = new Date()
+  utcFreeMarketResetTime.setUTCDate(utcFreeMarketResetTime.getUTCDate() - 1)
+  const utcFreeMarketMS = utcFreeMarketResetTime.setUTCHours(16, 0, 0, 0)
+  return utcFreeMarketMS
+}
+
 export const useHasCreatedContractToday = (user: User | null | undefined) => {
-  const [hasCreatedContractToday, setHasCreatedContractToday] = useState(
-    sessionCreatedContractToday
-  )
+  const [hasCreatedContractToday, setHasCreatedContractToday] = useState<
+    boolean | 'loading'
+  >('loading')
 
   useEffect(() => {
-    // Uses utc time like the server.
-    const utcTimeString = new Date().toISOString()
-    const todayAtMidnight = new Date(utcTimeString).setUTCHours(0, 0, 0, 0)
-
+    setHasCreatedContractToday('loading')
+    const todayAtMidnight = getUtcFreeMarketResetTimeToday()
     async function listUserContractsForToday() {
       if (!user) return
 

web/pages/create.tsx

@@ -77,7 +77,7 @@ export function NewContract(props: { question: string; tag?: string }) {
 
   const [ante, setAnte] = useState(FIXED_ANTE)
 
-  const deservesDailyFreeMarket = !useHasCreatedContractToday(creator)
+  const mustWaitForDailyFreeMarketStatus = useHasCreatedContractToday(creator)
 
   // useEffect(() => {
   //   if (ante === null && creator) {
@@ -107,7 +107,9 @@ export function NewContract(props: { question: string; tag?: string }) {
     ante !== undefined &&
     ante !== null &&
     ante >= MINIMUM_ANTE &&
-    (ante <= balance || deservesDailyFreeMarket) &&
+    (ante <= balance ||
+      (mustWaitForDailyFreeMarketStatus != 'loading' &&
+        !mustWaitForDailyFreeMarketStatus)) &&
     // closeTime must be in the future
     closeTime &&
     closeTime > Date.now() &&
@@ -368,13 +370,15 @@ export function NewContract(props: { question: string; tag?: string }) {
       <div className="form-control mb-1 items-start">
         <label className="label mb-1 gap-2">
           <span>Cost</span>
-          {!deservesDailyFreeMarket && (
+          {mustWaitForDailyFreeMarketStatus != 'loading' &&
+            mustWaitForDailyFreeMarketStatus && (
               <InfoTooltip
                 text={`Cost to create your market. This amount is used to subsidize trading.`}
               />
             )}
         </label>
-        {deservesDailyFreeMarket ? (
+        {mustWaitForDailyFreeMarketStatus != 'loading' &&
+        !mustWaitForDailyFreeMarketStatus ? (
           <div className="label-text text-primary pl-1">
             <span className={'label-text text-neutral line-through '}>
               {formatMoney(ante)}
@@ -382,11 +386,15 @@ export function NewContract(props: { question: string; tag?: string }) {
             FREE
           </div>
         ) : (
+          mustWaitForDailyFreeMarketStatus != 'loading' && (
             <div className="label-text text-neutral pl-1">
               {formatMoney(ante)}
             </div>
+          )
         )}
-        {!deservesDailyFreeMarket && ante > balance && (
+        {mustWaitForDailyFreeMarketStatus != 'loading' &&
+          mustWaitForDailyFreeMarketStatus &&
+          ante > balance && (
             <div className="mb-2 mt-2 mr-auto self-center whitespace-nowrap text-xs font-medium tracking-wide">
               <span className="mr-2 text-red-500">Insufficient balance</span>
               <button