Added story index management via query on homepage

Related to #27

front/src/hooks/index.ts

@@ -1,3 +1,4 @@
 export { default as useStoryDimensions } from './useStoryDimensions'
 export { default as useSend } from './useSend'
 export { default as useFetch } from './useFetch'
+export { default as UseStoryIndex } from './useStoryIndex'

front/src/hooks/useStoryIndex.ts

@@ -0,0 +1,47 @@
+import { useEffect, useState } from 'react'
+import { useSearchParams } from 'react-router-dom'
+import { SetState } from '../utils/types'
+
+function useStoryIndex(annLength: number | undefined) {
+    const [index, setIndex] = useState(0)
+
+    const [searchParams, setSearchParams] = useSearchParams()
+
+    const withReset = <T>(f: SetState<T>) => (...args: Parameters<SetState<T>>) => {
+        console.log('resetting index')
+        setIndex(0)
+        setSearchParams(prev => ({ ...prev, storyIndex: '0' }), { replace: true })
+        f(...args)
+    }
+
+    useEffect(() => {
+        setIndex(annLength ?
+            Number.parseInt(searchParams.get('storyIndex') || '0') :
+            0)
+        // searchParams have actual query string at first render
+        // eslint-disable-next-line react-hooks/exhaustive-deps
+    }, [annLength])
+
+    const increment = () => setIndex(prev => {
+        const newIndex = (prev + 1) % (annLength || 1)
+        setSearchParams(prev => ({ ...prev, storyIndex: newIndex.toString() }), { replace: true })
+
+        return newIndex
+    })
+
+    const decrement = () => setIndex(prev => {
+        const newIndex = prev > 0 ? (prev - 1) : 0
+        setSearchParams(prev => ({ ...prev, storyIndex: newIndex.toString() }), { replace: true })
+
+        return newIndex
+    })
+
+    return {
+        n: index,
+        withReset,
+        increment,
+        decrement
+    }
+}
+
+export default useStoryIndex

front/src/pages/HomePage.tsx

@@ -1,4 +1,4 @@
-import { CSSProperties, useEffect, useState } from 'react'
+import { CSSProperties, useEffect, useMemo, useState } from 'react'
 import Stories from 'react-insta-stories'
 import { Story } from 'react-insta-stories/dist/interfaces'
 
@@ -10,7 +10,8 @@ import { Announcement } from '../api/announcement/types'
 import { categoryGraphics } from '../assets/category'
 
 import puffSpinner from '../assets/puff.svg'
-import { gotError } from '../hooks/useFetch'
+import { UseFetchReturn, gotError } from '../hooks/useFetch'
+import useStoryIndex from '../hooks/useStoryIndex'
 
 function generateStories(announcements: Announcement[]): Story[] {
     return announcements.map(announcement => {
@@ -23,14 +24,14 @@ function generateStories(announcements: Announcement[]): Story[] {
     })
 }
 
-function fallbackGenerateStories(announcementsFetch: ReturnType<typeof useAnnouncements>) {
-    if (announcementsFetch.loading)
+function fallbackGenerateStories(announcements: UseFetchReturn<Announcement[]>) {
+    if (announcements.loading)
         return fallbackStory()
 
-    if (gotError(announcementsFetch))
-        return fallbackStory(announcementsFetch.error, true)
+    if (gotError(announcements))
+        return fallbackStory(announcements.error, true)
 
-    const stories = generateStories(announcementsFetch.data)
+    const stories = generateStories(announcements.data)
 
     if (stories.length === 0)
         return fallbackStory('Здесь пока пусто')
@@ -68,14 +69,21 @@ function HomePage() {
     const [filterShown, setFilterShown] = useState(false)
     const [filter, setFilter] = useState(defaultFilters)
 
-    const announcementsFetch = useAnnouncements(filter)
 
-    const stories = fallbackGenerateStories(announcementsFetch)
+    const announcements = useAnnouncements(filter)
+
+    const stories = useMemo(() => fallbackGenerateStories(announcements), [announcements])
+
+    const index = useStoryIndex(announcements.data?.length)
 
     return (<>
-        <Filters filter={filter} setFilter={setFilter} filterShown={filterShown} setFilterShown={setFilterShown} />
+        <Filters filter={filter} setFilter={index.withReset(setFilter)} filterShown={filterShown} setFilterShown={setFilterShown} />
         <div style={styles.container}>
             <Stories
+                currentIndex={index.n}
+                onStoryEnd={index.increment}
+                onNext={index.increment}
+                onPrevious={index.decrement}
                 stories={stories}
                 defaultInterval={11000}
                 height={height}