feat(web/js): add wasm client side runner

Signed-off-by: Xe Iaso <me@xeiaso.net>

web/js/worker/wasm.ts

@@ -0,0 +1,106 @@
+export interface Args {
+  data: string;
+  difficulty: number;
+  nonce: number;
+  threads: number;
+  module: BufferSource;
+}
+
+interface AnubisExports {
+  anubis_work: (difficulty: number, initialNonce: number, threads: number) => number;
+  data_ptr: () => number;
+  result_hash_ptr: () => number;
+  result_hash_size: () => number;
+  set_data_length: (len: number) => void;
+  memory: WebAssembly.Memory;
+}
+
+addEventListener("message", async (event: MessageEvent<Args>) => {
+  console.log(event.data);
+  const { data, difficulty, threads, module } = event.data;
+  let { nonce } = event.data;
+
+  const importObject = {
+    anubis: {
+      anubis_update_nonce: (nonce: number) => postMessage(nonce),
+    }
+  };
+
+  if (nonce !== 0) {
+    importObject.anubis.anubis_update_nonce = (_) => { };
+  }
+
+  const obj = await WebAssembly.instantiate(module, importObject);
+
+  const {
+    anubis_work,
+    data_ptr,
+    result_hash_ptr,
+    result_hash_size,
+    set_data_length,
+    memory
+  } = (obj as unknown as any).exports as unknown as AnubisExports;
+  function uint8ArrayToHex(arr: Uint8Array) {
+    return Array.from(arr)
+      .map((c) => c.toString(16).padStart(2, "0"))
+      .join("");
+  }
+
+  function hexToUint8Array(hexString: string): Uint8Array {
+    // Remove whitespace and optional '0x' prefix
+    hexString = hexString.replace(/\s+/g, '').replace(/^0x/, '');
+
+    // Check for valid length
+    if (hexString.length % 2 !== 0) {
+      throw new Error('Invalid hex string length');
+    }
+
+    // Check for valid characters
+    if (!/^[0-9a-fA-F]+$/.test(hexString)) {
+      throw new Error('Invalid hex characters');
+    }
+
+    // Convert to Uint8Array
+    const byteArray = new Uint8Array(hexString.length / 2);
+    for (let i = 0; i < byteArray.length; i++) {
+      const byteValue = parseInt(hexString.substr(i * 2, 2), 16);
+      byteArray[i] = byteValue;
+    }
+
+    return byteArray;
+  }
+
+  // Write data to buffer
+  function writeToBuffer(data: Uint8Array) {
+    if (data.length > 1024) throw new Error("Data exceeds buffer size");
+
+    // Get pointer and create view
+    const offset = data_ptr();
+    const buffer = new Uint8Array(memory.buffer, offset, data.length);
+
+    // Copy data
+    buffer.set(data);
+
+    // Set data length
+    set_data_length(data.length);
+  }
+
+  function readFromChallenge() {
+    const offset = result_hash_ptr();
+    const buffer = new Uint8Array(memory.buffer, offset, result_hash_size());
+
+    return buffer;
+  }
+
+  writeToBuffer(hexToUint8Array(data));
+
+  nonce = anubis_work(difficulty, nonce, threads);
+  const challenge = readFromChallenge();
+  const result = uint8ArrayToHex(challenge);
+
+  postMessage({
+    hash: result,
+    difficulty,
+    nonce,
+  });
+});