/**
* Deep binary inspection: understand exactly what the dump format is.
*/
import * as Y from "yjs";
import * as decoding from "lib0/decoding";
import { loadEncryptedCookie } from "../src/crypto.js";
const WS_ID = "45h7lom5ryjak34u";
const HOST = "inkabeam.nimbusweb.me";
async function main() {
const stored = loadEncryptedCookie();
if (!stored) throw new Error("No cookie");
const cookie = stored.cookie;
// Use our V1-written page (small, known)
const pageId = "7SGBAZlCo2B88dfg";
console.log(`=== Page: ${pageId} ===`);
const resp = await fetch(`https://${HOST}/dump/${WS_ID}/${pageId}`, {
headers: { cookie },
});
const binary = new Uint8Array(await resp.arrayBuffer());
console.log(`Size: ${binary.length} bytes`);
console.log(`First 20 bytes hex: ${Array.from(binary.slice(0, 20)).map(b => b.toString(16).padStart(2, '0')).join(' ')}`);
// Try to decode header manually
const decoder = decoding.createDecoder(binary);
// Y.js update format starts with:
// varuint: number of client structs
// for each struct group:
// varuint: client ID
// varuint: clock start
// for each struct:
// byte: info (content type + additional info)
console.log("\n--- Manual decode attempt ---");
try {
// First byte should be update format or a version byte
const firstByte = decoding.readUint8(decoder);
console.log(`First byte: ${firstByte} (0x${firstByte.toString(16)})`);
// If firstByte is 0 or 1, it might be a version header
// Then try reading the actual structure count
const structCount = decoding.readVarUint(decoder);
console.log(`Struct count (or next varuint): ${structCount}`);
// Try reading next few values
for (let i = 0; i < 5; i++) {
try {
const val = decoding.readVarUint(decoder);
console.log(` varuint[${i}]: ${val}`);
} catch { break; }
}
} catch (e) {
console.log(`Manual decode error: ${(e as Error).message}`);
}
// The key question: is this a V2 update with a version prefix?
// Y.js V2 updates start with version byte 0x01 then the actual data
// Let's try stripping the first byte and applying as V1
console.log("\n--- Try skip first byte, apply as V1 ---");
try {
const doc = new Y.Doc();
Y.applyUpdate(doc, binary.slice(1));
console.log("SUCCESS! Skipping first byte works for V1");
const root = doc.getMap("root");
console.log(`root keys: ${JSON.stringify(Array.from(root.keys()))}`);
} catch (e) {
console.log(`FAILED: ${(e as Error).message}`);
}
// Or maybe the format is: first byte = version, rest = V2 update
console.log("\n--- Try skip first byte, apply as V2 ---");
try {
const doc = new Y.Doc();
Y.applyUpdateV2(doc, binary.slice(1));
console.log("SUCCESS! Skipping first byte works for V2");
const root = doc.getMap("root");
console.log(`root keys: ${JSON.stringify(Array.from(root.keys()))}`);
} catch (e) {
console.log(`FAILED: ${(e as Error).message}`);
}
// Try Y.encodeStateAsUpdate / Y.encodeStateAsUpdateV2 to understand expected format
console.log("\n--- Create a known doc, compare format ---");
const testDoc = new Y.Doc();
testDoc.getMap("root").set("test", "hello");
const v1Update = Y.encodeStateAsUpdate(testDoc);
const v2Update = Y.encodeStateAsUpdateV2(testDoc);
console.log(`V1 update first 20 bytes: [${Array.from(v1Update.slice(0, 20)).join(", ")}]`);
console.log(`V2 update first 20 bytes: [${Array.from(v2Update.slice(0, 20)).join(", ")}]`);
// What if the dump contains multiple updates concatenated?
// Or what if it's a document state (not an update)?
console.log("\n--- Try as document state (encodeStateVector + full state) ---");
// In the WebSocket protocol, the server sends syncStep2 which IS an update
// But the dump endpoint might use a different format
// Actually let me check: does the WS URL have encv2=true?
// Our V1 writer dropped encv2=true from the URL
// But maybe the server still stores in V2 format?
// Let me look at the actual binary content as text to see structure
console.log("\n--- Binary as text (showing readable segments) ---");
const text = new TextDecoder('utf-8', { fatal: false }).decode(binary);
const readable = text.replace(/[^\x20-\x7E\n]/g, '·');
// Show first 500 chars
console.log(readable.substring(0, 500));
}
main().catch(e => { console.error(e); process.exit(1); });
