it works!

client/src/components/Home.tsx

@@ -41,26 +41,10 @@ const Home = () => {
     return uniqEvents.filter(e => e.tags.some(tag => tag[0] === 'e' && tag[1] === event.id)).length;
   }
 
-  const [messageFromWorker, setMessageFromWorker] = useState('');
-
-  useEffect(() => {
-    const worker = new Worker(new URL('../myWorker', import.meta.url));
-
-    worker.onmessage = (event) => {
-      setMessageFromWorker(event.data);
-    };
-
-    worker.postMessage('Start worker');
-    return () => {
-      worker.terminate();
-    };
-  }, []);
-
   return (
     <main className="bg-black text-white min-h-screen">
       <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-4 p-4">
         <NewThreadCard />
-        <p>Message from worker: {messageFromWorker}</p>
         {filteredAndSortedEvents.map((event, index) => (
           <PostCard key={event.id} event={event} metadata={getMetadataEvent(event)} replyCount={countReplies(event)}/>
         ))}

client/src/components/PostCard/NewThreadCard.tsx

@@ -1,6 +1,6 @@
 import CardContainer from './CardContainer';
 import { ArrowUpTrayIcon, CpuChipIcon } from '@heroicons/react/24/outline';
-import { useState } from 'react';
+import { useState, useEffect, useMemo } from 'react';
 import { generatePrivateKey, getPublicKey, finishEvent } from 'nostr-tools';
 import { minePow } from '../../utils/mine';
 import { publish } from '../../utils/relays';
@@ -11,30 +11,51 @@ const difficulty = 20
 const NewThreadCard: React.FC = () => {
   const [comment, setComment] = useState("");
   const [file, setFile] = useState("");
+  const [sk, setSk] =  useState(generatePrivateKey());
+  
+  const [messageFromWorker, setMessageFromWorker] = useState(null);
+    // Initialize the worker outside of any effects
+  const worker = useMemo(() => new Worker(new URL('../../powWorker', import.meta.url)), []);
+
+  useEffect(() => {
+    worker.onmessage = (event) => {
+      setMessageFromWorker(event.data);
+    };
+  }, []);
 
   const handleSubmit = async (event: React.FormEvent<HTMLFormElement>) => {
     event.preventDefault();
-    let sk = generatePrivateKey();
+    worker.postMessage({
-
+        unsigned: {
-    try {
-      const event = minePow({
             kind: 1,  
             tags: [],
             content: comment + " " + file,
             created_at: Math.floor(Date.now() / 1000),
             pubkey: getPublicKey(sk),
-      }, difficulty);
+        },
-
+        difficulty
-      const signedEvent = finishEvent(event, sk);
+    });
-      await publish(signedEvent);
-      
-      setComment("")
-      setFile("")
-    } catch (error) {
-      setComment(comment + " " + error);
-    }
   };
 
+  useEffect(() => {
+    if (messageFromWorker) {
+        try {
+            const signedEvent = finishEvent(messageFromWorker, sk);
+            publish(signedEvent);
+
+            setComment("");
+            setFile("");
+            setSk(generatePrivateKey())
+
+            return () => {
+              worker.terminate();
+            };
+        } catch (error) {
+            setComment(error + ' ' + comment);
+        }
+    }
+}, [messageFromWorker]);
+
   async function attachFile(file_input: File | null) {
     try {
       if (file_input) {
@@ -55,6 +76,7 @@ const NewThreadCard: React.FC = () => {
   return (
     <>
       <CardContainer>
+        {/* <p>Message from worker: {messageFromWorker}</p> */}
         <form
           name="post"
           method="post"

client/src/myWorker.ts

@@ -1,11 +0,0 @@
-// eslint-disable-next-line no-restricted-globals
-const ctx: Worker = self as any;
-
-// Respond to message from parent thread
-ctx.addEventListener('message', (event) => {
-    setTimeout(() => {
-        ctx.postMessage('Hello from Worker after 2 seconds');
-    }, 2000);
-});
-
-export default ctx;

client/src/powWorker.ts

@@ -0,0 +1,74 @@
+import { type UnsignedEvent, type Event, getEventHash } from 'nostr-tools'
+
+// eslint-disable-next-line no-restricted-globals
+const ctx: Worker = self as any;
+
+// Respond to message from parent thread
+ctx.addEventListener('message', (event) => {
+    console.log("Received message in worker:", event.data);
+    
+    const { unsigned, difficulty } = event.data;
+    
+    const result = minePow(unsigned, difficulty);
+    console.log("Mining result:", result);
+    
+    // Post the mined event back to the main thread
+    ctx.postMessage(result);
+});
+
+ctx.onerror = function(e) {
+    console.error("Worker error:", e);
+};
+
+/** Get POW difficulty from a Nostr hex ID. */
+export function getPow(hex: string): number {
+    let count = 0
+
+    for (let i = 0; i < hex.length; i++) {
+        const nibble = parseInt(hex[i], 16)
+        if (nibble === 0) {
+            count += 4
+        } else {
+            count += Math.clz32(nibble) - 28
+            break
+        }
+    }
+
+    return count
+}
+
+/**
+ * Mine an event with the desired POW. This function mutates the event.
+ * Note that this operation is synchronous and should be run in a worker context to avoid blocking the main thread.
+ *
+ * Adapted from Snort: https://git.v0l.io/Kieran/snort/src/commit/4df6c19248184218c4c03728d61e94dae5f2d90c/packages/system/src/pow-util.ts#L14-L36
+ */
+export function minePow<K extends number>(unsigned: UnsignedEvent<K>, difficulty: number): Omit<Event<K>, 'sig'> {
+    let count = 0
+
+    const event = unsigned as Omit<Event<K>, 'sig'>
+    const tag = ['nonce', count.toString(), difficulty.toString()]
+
+    event.tags.push(tag)
+
+    while (true) {
+        const now = Math.floor(new Date().getTime() / 1000)
+
+        if (now !== event.created_at) {
+            count = 0
+            event.created_at = now
+        }
+
+        tag[1] = (++count).toString()
+
+        event.id = getEventHash(event)
+
+        if (getPow(event.id) >= difficulty) {
+            break
+        }
+    }
+
+    return event
+}
+
+export default ctx;