optimise processing

client/src/hooks/processedEvents.ts

@@ -1,4 +1,4 @@
-import { useState, useEffect } from 'react';
+import { useState, useEffect, useMemo } from 'react'; // Import useMemo
 import { verifyPow } from '../utils/mine';
 import { useFetchEvents } from './useFetchEvents';
 import { Event } from 'nostr-tools';
@@ -7,27 +7,47 @@ type ProcessedEvent = {
   postEvent: Event;
   replies: Event[];
   totalWork: number;
-  metadataEvent: Event | null; // Added metadataEvent to the type
+  metadataEvent: Event | null;
 };
 
 const useProcessedEvents = (id?: string, filterDifficulty: number = 0) => {
-  const { noteEvents, metadataEvents } = useFetchEvents(id, false); // Reintroduced metadataEvents
+  const { noteEvents, metadataEvents } = useFetchEvents(id, false);
   const [processedEvents, setProcessedEvents] = useState<ProcessedEvent[]>([]);
 
-  useEffect(() => {
-    const processed = noteEvents
-      .filter(event => verifyPow(event) >= filterDifficulty && event.kind !== 0)
-      .filter(event => !(event.kind === 1 && event.tags.some(tag => tag[0] === 'e')))
+  // Use useMemo to memoize the processed events
+  const processed = useMemo(() => {
+    // Create a map for replies to optimize lookup
+    const repliesMap = new Map<string, Event[]>();
+    noteEvents.forEach(event => {
+      event.tags.forEach(tag => {
+        if (tag[0] === 'e') {
+          const replyToId = tag[1];
+          if (!repliesMap.has(replyToId)) {
+            repliesMap.set(replyToId, []);
+          }
+          repliesMap.get(replyToId)?.push(event);
+        }
+      });
+    });
+
+    return noteEvents
+      .filter(event => {
+        const pow = verifyPow(event);
+        return (event.kind === 0 || pow >= filterDifficulty) && !(event.kind === 1 && event.tags.some(tag => tag[0] === 'e'));
+      })
       .map(event => {
-        const replies = noteEvents.filter(e => e.tags.some(tag => tag[0] === 'e' && tag[1] === event.id));
-        const totalWork = Math.pow(2, verifyPow(event)) + replies.reduce((acc, reply) => acc + Math.pow(2, verifyPow(reply)), 0);
-        const metadataEvent = metadataEvents.find((e) => e.pubkey === event.pubkey && e.kind === 0) || null; // Find the corresponding metadataEvent
-        return { postEvent: event, replies, totalWork, metadataEvent }; // Include metadataEvent in the returned object
+        const pow = verifyPow(event); // Calculate once and reuse
+        const replies = repliesMap.get(event.id) || [];
+        const totalWork = Math.pow(2, pow) + replies.reduce((acc, reply) => acc + Math.pow(2, verifyPow(reply)), 0);
+        const metadataEvent = metadataEvents.find(e => e.pubkey === event.pubkey && e.kind === 0) || null;
+        return { postEvent: event, replies, totalWork, metadataEvent };
       })
       .sort((a, b) => b.totalWork - a.totalWork || b.postEvent.created_at - a.postEvent.created_at);
+  }, [noteEvents, metadataEvents, id, filterDifficulty]); // Dependencies for useMemo
 
+  useEffect(() => {
     setProcessedEvents(processed);
-  }, [noteEvents, metadataEvents, id, filterDifficulty]); // Include metadataEvents in the dependency array
+  }, [processed]); // Depend on the memoized processed events
 
   return { processedEvents };
 };