/**
* Full analysis of the dump binary format with the discovered 3-byte offset.
*/
import * as Y from "yjs";
import { loadEncryptedCookie } from "../src/crypto.js";
const HOST = "inkabeam.nimbusweb.me";
const WS_ID = "45h7lom5ryjak34u";
const PAGE = process.argv[2] || "0ylYPzWyJEE9GHQN";
async function main() {
const stored = loadEncryptedCookie();
if (!stored?.cookie) { console.error("No cookie"); process.exit(1); }
const res = await fetch(`https://${HOST}/dump/${WS_ID}/${PAGE}`, {
headers: { cookie: stored.cookie },
});
const buf = await res.arrayBuffer();
const data = new Uint8Array(buf);
console.log(`📦 Dump: ${data.byteLength} bytes`);
console.log(` Header: ${Array.from(data.slice(0, 3)).map(b => '0x' + b.toString(16).padStart(2, '0')).join(' ')}`);
let len = 0, shift = 0, idx = 1;
let byte: number;
do {
byte = data[idx++];
len |= (byte & 0x7f) << shift;
shift += 7;
} while (byte & 0x80);
const yjsData = data.slice(idx, idx + len);
const doc = new Y.Doc();
Y.applyUpdate(doc, yjsData);
// Inspect structure
const root = doc.getMap("root");
console.log(`\n📊 Root keys: ${JSON.stringify(Array.from(root.keys()))}`);
const children = root.get("children");
if (children instanceof Y.Array) {
console.log(`\n children (${children.length}):`);
for (let i = 0; i < children.length; i++) {
console.log(` [${i}]: ${JSON.stringify(children.get(i))}`);
}
}
const rootChildren = doc.getArray("rootChildren");
if (rootChildren instanceof Y.Array) {
console.log(`\n rootChildren (${rootChildren.length}):`);
for (let i = 0; i < rootChildren.length; i++) {
console.log(` [${i}]: ${JSON.stringify(rootChildren.get(i))}`);
}
}
const blocks = doc.getMap("blocks");
if (blocks instanceof Y.Map) {
console.log(`\n blocks (${blocks.size}):`);
for (const [key, val] of blocks.entries()) {
console.log(`\n 📄 Block "${key}":`);
if (val instanceof Y.Map) {
for (const [k, v] of (val as Y.Map<unknown>).entries()) {
if (k === "characters" && v instanceof Y.Array) {
const arr = v.toArray();
console.log(` ${k}: ${JSON.stringify(arr)}`);
} else if (v instanceof Y.Map) {
console.log(` ${k}: Y.Map{${JSON.stringify(Object.fromEntries((v as Y.Map<unknown>).entries()))}}`);
} else {
console.log(` ${k}: ${JSON.stringify(v)}`);
}
}
}
}
}
// Now test: can we modify this doc and re-encode?
console.log("\n\n🔬 Testing doc modification...");
// Get the state vector before changes
const sv = Y.encodeStateVector(doc);
// Add a new block
const newBlockId = `b${Date.now()}_99`;
const blocksMapResolved = doc.getMap("blocks") as Y.Map<unknown>;
const childrenArr = root.get("children") as Y.Array<string>;
const rootChildrenArr = doc.getArray("rootChildren") as Y.Array<string>;
const newBlock = new Y.Map();
newBlock.set("id", newBlockId);
newBlock.set("type", "paragraph");
newBlock.set("indent", 0);
newBlock.set("color", "transparent");
newBlock.set("align", "left");
const chars = new Y.Array();
const text = "Written via Y.js API!";
chars.push(text.split(""));
newBlock.set("characters", chars);
blocksMapResolved.set(newBlockId, newBlock);
childrenArr.push([newBlockId]);
rootChildrenArr.push([newBlockId]);
// Get the diff update
const diffUpdate = Y.encodeStateAsUpdate(doc, sv);
console.log(` Diff update size: ${diffUpdate.byteLength} bytes`);
console.log(` Diff (base64): ${Buffer.from(diffUpdate).toString("base64")}`);
// Full state after changes
const fullState = Y.encodeStateAsUpdate(doc);
console.log(` Full state size: ${fullState.byteLength} bytes`);
// Reconstruct the dump format: 3-byte header + Y.js update
// Header bytes from original: 01 db 03
// Let's check: is 01 the version and db 03 the length?
// 0xdb = 219, 0x03 = 3 → little-endian uint16 = 0x03db = 987? Original data was 478 bytes...
// Actually Yjs uses its own encoding lib. Byte 0 could be a custom tag.
// Let's try encoding the dump ourselves.
// The header bytes 01 db 03 could be:
// 0x01 = version
// 0xdb 0x03 = varint encoding of the update length
// In Y.js varint: 0xdb = 1011011 with high bit set (219), so value = 219-128=91 + (3 << 7) = 91 + 384 = 475
// That's 475! Original data was 478 bytes, minus 3 byte header = 475. Match!
console.log(`\n🔍 Header analysis:`);
console.log(` Byte 0: 0x01 (version)`);
console.log(` Bytes 1-2: varint(${(data[1] & 0x7f) + (data[2] << 7)}) = ${(data[1] & 0x7f) + (data[2] << 7)} (matches data length ${data.byteLength - 3})`);
// Now let's try POSTing the diff update directly back to the dump endpoint
// wrapped with the same header format
const headerSize = 3; // Depends on varint size
console.log(`\n☑️ Doc verified — can read and modify Fusebase Y.Doc`);
}
main().catch(console.error);
