Live via service config (#8378)

* add config (with temp config)

* only allow whitelisted domains in form

* move config to generic config

* use array-based config

* update deps

* rm expect-error

src/state/service-config.tsx

@@ -0,0 +1,88 @@
+import {createContext, useContext, useMemo} from 'react'
+
+import {useLanguagePrefs} from '#/state/preferences/languages'
+import {useServiceConfigQuery} from '#/state/queries/service-config'
+import {device} from '#/storage'
+
+type TrendingContext = {
+  enabled: boolean
+}
+
+type LiveNowContext = {
+  did: string
+  domains: string[]
+}[]
+
+const TrendingContext = createContext<TrendingContext>({
+  enabled: false,
+})
+
+const LiveNowContext = createContext<LiveNowContext | null>(null)
+
+export function Provider({children}: {children: React.ReactNode}) {
+  const langPrefs = useLanguagePrefs()
+  const {data: config, isLoading: isInitialLoad} = useServiceConfigQuery()
+  const trending = useMemo<TrendingContext>(() => {
+    if (__DEV__) {
+      return {enabled: true}
+    }
+
+    /*
+     * Only English during beta period
+     */
+    if (
+      !!langPrefs.contentLanguages.length &&
+      !langPrefs.contentLanguages.includes('en')
+    ) {
+      return {enabled: false}
+    }
+
+    /*
+     * While loading, use cached value
+     */
+    const cachedEnabled = device.get(['trendingBetaEnabled'])
+    if (isInitialLoad) {
+      return {enabled: Boolean(cachedEnabled)}
+    }
+
+    /*
+     * Doing an extra check here to reduce hits to statsig. If it's disabled on
+     * the server, we can exit early.
+     */
+    const enabled = Boolean(config?.topicsEnabled)
+
+    // update cache
+    device.set(['trendingBetaEnabled'], enabled)
+
+    return {enabled}
+  }, [isInitialLoad, config, langPrefs.contentLanguages])
+
+  const liveNow = useMemo<LiveNowContext>(() => config?.liveNow ?? [], [config])
+
+  return (
+    <TrendingContext.Provider value={trending}>
+      <LiveNowContext.Provider value={liveNow}>
+        {children}
+      </LiveNowContext.Provider>
+    </TrendingContext.Provider>
+  )
+}
+
+export function useTrendingConfig() {
+  return useContext(TrendingContext)
+}
+
+export function useLiveNowConfig() {
+  const ctx = useContext(LiveNowContext)
+  if (!ctx) {
+    throw new Error(
+      'useLiveNowConfig must be used within a LiveNowConfigProvider',
+    )
+  }
+  return ctx
+}
+
+export function useCanGoLive(did?: string) {
+  const config = useLiveNowConfig()
+  return !!config.find(cfg => cfg.did === did)
+}