Revert makeFeed changes

src/app/core/requests.ts

@@ -1,4 +1,4 @@
-import {get, writable, derived} from "svelte/store"
+import {get, writable} from "svelte/store"
 import {
   uniq,
   int,
@@ -24,10 +24,10 @@ import {
 import type {TrustedEvent, Filter, List} from "@welshman/util"
 import {feedFromFilters, makeRelayFeed, makeIntersectionFeed} from "@welshman/feeds"
 import {load, request} from "@welshman/net"
-import {repository, makeFeedController, loadRelay} from "@welshman/app"
+import {repository, makeFeedController, loadRelay, tracker} from "@welshman/app"
 import {createScroller} from "@lib/html"
 import {daysBetween} from "@lib/util"
-import {getEventsForUrl, deriveEventsForUrlDesc} from "@app/core/state"
+import {getEventsForUrl} from "@app/core/state"
 
 // Utils
 
@@ -42,12 +42,56 @@ export const makeFeed = ({
   element: HTMLElement
   onExhausted?: () => void
 }) => {
+  const seen = new Set<string>()
   const controller = new AbortController()
-  const allEvents = deriveEventsForUrlDesc(url, filters)
-  const total = derived(allEvents, $allEvents => $allEvents.length)
-  const limit = writable(0)
+  const buffer = writable<TrustedEvent[]>([])
+  const events = writable<TrustedEvent[]>([])
 
-  const events = derived([allEvents, limit], ([$allEvents, $limit]) => $allEvents.slice(0, $limit))
+  const insertEvent = (event: TrustedEvent) => {
+    let handled = false
+
+    if (seen.has(event.id)) {
+      return
+    }
+
+    events.update($events => {
+      for (let i = 0; i < $events.length; i++) {
+        if ($events[i].id === event.id) return $events
+        if ($events[i].created_at < event.created_at) {
+          handled = true
+          return insertAt(i, event, $events)
+        }
+      }
+
+      return $events
+    })
+
+    if (!handled) {
+      buffer.update($buffer => {
+        for (let i = 0; i < $buffer.length; i++) {
+          if ($buffer[i].id === event.id) return $buffer
+          if ($buffer[i].created_at < event.created_at) return insertAt(i, event, $buffer)
+        }
+
+        return [...$buffer, event]
+      })
+    }
+
+    seen.add(event.id)
+  }
+
+  const unsubscribe = on(repository, "update", ({added, removed}) => {
+    if (removed.size > 0) {
+      buffer.update($buffer => $buffer.filter(e => !removed.has(e.id)))
+      events.update($events => $events.filter(e => !removed.has(e.id)))
+    }
+
+    for (const event of added) {
+      if (matchFilters(filters, event) && tracker.getRelays(event.id).has(url)) {
+        insertEvent(event)
+      }
+    }
+  })
 
   const ctrl = makeFeedController({
     useWindowing: true,
@@ -59,22 +103,26 @@ export const makeFeed = ({
   const scroller = createScroller({
     element,
     delay: 300,
-    threshold: 8_000,
+    threshold: 10_000,
     onScroll: async () => {
-      console.log(get(events).length, get(allEvents).length)
-      limit.update($limit => {
-        if (get(total) - $limit < 100) {
-          ctrl.load(100)
-        }
+      const $buffer = get(buffer)
 
-        return $limit + 10
-      })
+      events.update($events => [...$events, ...$buffer.splice(0, 30)])
+
+      if ($buffer.length < 100) {
+        ctrl.load(100)
+      }
     },
   })
 
+  for (const event of getEventsForUrl(url, filters)) {
+    insertEvent(event)
+  }
+
   return {
     events,
     cleanup: () => {
+      unsubscribe()
       scroller.stop()
       controller.abort()
     },