encoder wip

src/Data/ParserState.ts

@@ -28,9 +28,13 @@ export class ParserState {
 	public instanceBaselines: [Map<EntityId, SendProp[]>, Map<EntityId, SendProp[]>] = [new Map(), new Map()];
 	public skippedPackets: PacketTypeId[] = [];
 	public userInfoEntries: Map<string, BitStream> = new Map();
+	public tick: number = 0;
 
 	public handlePacket(packet: Packet) {
 		switch (packet.packetType) {
+			case 'netTick':
+				this.tick = packet.tick;
+				break;
 			case 'serverInfo':
 				this.version = packet.version;
 				break;

src/Demo.ts

@@ -4,13 +4,8 @@ import {PacketTypeId} from './Data/Packet';
 import {Parser} from './Parser';
 
 export class Demo {
-	public static fromNodeBuffer(nodeBuffer) {
+	public static fromNodeBuffer(nodeBuffer: Buffer) {
-		const arrayBuffer = new ArrayBuffer(nodeBuffer.length);
+		return new Demo(nodeBuffer.buffer as ArrayBuffer);
-		const view = new Uint8Array(arrayBuffer);
-		for (let i = 0; i < nodeBuffer.length; ++i) {
-			view[i] = nodeBuffer[i];
-		}
-		return new Demo(arrayBuffer);
 	}
 
 	public stream: BitStream;

src/Encoder.ts

@@ -0,0 +1,48 @@
+import {BitStream} from 'bit-buffer';
+import {Header} from './Data/Header';
+import {Message, MessageType} from './Data/Message';
+import {ParserState} from './Data/ParserState';
+import {messageHandlers} from './Parser';
+
+export class Encoder {
+	public readonly stream: BitStream;
+	public readonly parserState: ParserState;
+
+	constructor(stream: BitStream) {
+		this.stream = stream;
+		this.parserState = new ParserState();
+	}
+
+	public encodeHeader(header: Header) {
+		this.stream.writeASCIIString(header.type, 8);
+		this.stream.writeUint32(header.version);
+		this.stream.writeUint32(header.protocol);
+		this.stream.writeASCIIString(header.server, 260);
+		this.stream.writeASCIIString(header.nick, 260);
+		this.stream.writeASCIIString(header.map, 260);
+		this.stream.writeASCIIString(header.game, 260);
+		this.stream.writeFloat32(header.duration);
+		this.stream.writeUint32(header.ticks);
+		this.stream.writeUint32(header.frames);
+		this.stream.writeUint32(header.sigon);
+	}
+
+	public writeMessage(message: Message) {
+		this.stream.writeUint8(message.type);
+		const handler = messageHandlers.get(message.type);
+		if (!handler) {
+			throw new Error(`No handler for message of type ${MessageType[message.type]}`);
+		}
+		handler.encodeMessage(message, this.stream, this.parserState);
+		this.handleMessage(message);
+	}
+
+	protected handleMessage(message: Message) {
+		this.parserState.handleMessage(message);
+		if (message.type === MessageType.Packet) {
+			for (const packet of message.packets) {
+				this.parserState.handlePacket(packet);
+			}
+		}
+	}
+}

src/Parser.ts

@@ -6,18 +6,20 @@ import {ParserState} from './Data/ParserState';
 import {ConsoleCmdHandler} from './Parser/Message/ConsoleCmd';
 import {DataTableHandler} from './Parser/Message/DataTable';
 import {PacketMessageHandler} from './Parser/Message/Packet';
+import {StopHandler} from './Parser/Message/Stop';
 import {StringTableHandler} from './Parser/Message/StringTable';
 import {SyncTickHandler} from './Parser/Message/SyncTick';
 import {UserCmdHandler} from './Parser/Message/UserCmd';
 
-const messageHandlers: Map<MessageType, MessageHandler<Message>> = new Map<MessageType, MessageHandler<Message>>([
+export const messageHandlers: Map<MessageType, MessageHandler<Message>> = new Map<MessageType, MessageHandler<Message>>([
 	[MessageType.Sigon, PacketMessageHandler],
 	[MessageType.Packet, PacketMessageHandler],
 	[MessageType.ConsoleCmd, ConsoleCmdHandler],
 	[MessageType.UserCmd, UserCmdHandler],
 	[MessageType.DataTables, DataTableHandler],
 	[MessageType.StringTables, StringTableHandler],
-	[MessageType.SyncTick, SyncTickHandler]
+	[MessageType.SyncTick, SyncTickHandler],
+	[MessageType.Stop, StopHandler]
 ]);
 
 export class Parser {
@@ -50,22 +52,13 @@ export class Parser {
 	protected * getMessages(): Iterable<Message> {
 		while (true) {
 			const message = this.readMessage(this.stream, this.parserState);
-			if (message) {
 			yield message;
-			} else {
+			if (message.type === MessageType.Stop) {
 				return;
 			}
 		}
 	}
 
-	protected parseMessage(data: BitStream, type: MessageType, state: ParserState): Message {
-		const handler = messageHandlers.get(type);
-		if (!handler) {
-			throw new Error(`No handler for message of type ${MessageType[type]}`);
-		}
-		return handler.parseMessage(data, state);
-	}
-
 	protected parseHeader(stream): Header {
 		return {
 			type: stream.readASCIIString(8),
@@ -85,22 +78,28 @@ export class Parser {
 	protected * handleMessage(message: Message): Iterable<Packet> {
 		this.parserState.handleMessage(message);
 		if (message.type === MessageType.Packet) {
-			for (const packet of (message as PacketMessage).packets) {
+			for (const packet of message.packets) {
 				this.parserState.handlePacket(packet);
 				yield packet;
 			}
 		}
 	}
 
-	protected readMessage(stream: BitStream, state: ParserState): Message | false {
+	protected readMessage(stream: BitStream, state: ParserState): Message {
 		if (stream.bitsLeft < 8) {
-			return false;
+			throw new Error('Stream ended without stop packet');
 		}
 		const type: MessageType = stream.readUint8();
-		if (type === MessageType.Stop) {
+		if (type === 0) {
-			return false;
+			return {
+				type: MessageType.Stop,
+				rawData: stream.readBitStream(0)
+			};
 		}
-
+		const handler = messageHandlers.get(type);
-		return this.parseMessage(stream, type, state);
+		if (!handler) {
+			throw new Error(`No handler for message of type ${MessageType[type]}(${type})`);
+		}
+		return handler.parseMessage(this.stream, state);
 	}
 }

src/Parser/EntityDecoder.ts

@@ -9,11 +9,13 @@ export function getEntityUpdate(sendTable: SendTable, stream: BitStream): SendPr
 	let index = -1;
 	const allProps = sendTable.flattenedProps;
 	const props: Map<string, SendProp> = new Map();
+	let lastIndex = -1;
 	while (stream.readBoolean()) {
+		lastIndex = index;
 		index = readFieldIndex(stream, index);
 		if (index >= 4096 || index > allProps.length) {
-			throw new Error('prop index out of bounds while applying update for ' + sendTable.name + ' got ' + index
+			throw new Error(`prop index out of bounds while applying update for ${sendTable.name} 
-				+ ' property only has ' + allProps.length + ' properties');
+			got ${index} property only has ${allProps.length} properties (lastProp: ${lastIndex})`);
 		}
 
 		const propDefinition = allProps[index];
@@ -42,8 +44,8 @@ export function encodeEntityUpdate(props: SendProp[], sendTable: SendTable, stre
 		}
 
 		if (index < lastIndex) {
-			throw new Error(`Property index not incremental while encoding` +
+			throw new Error(`Property index not incremental while encoding ` +
-				`${prop.definition.fullName} after ${allProps[lastIndex].fullName}` +
+				`${prop.definition.fullName} after ${allProps[lastIndex].fullName} ` +
 				`in ${sendTable.name} (current: ${index}, last: ${lastIndex})`);
 		}
 		writeFieldIndex(index, stream, lastIndex);

src/Parser/Message/Stop.ts

@@ -0,0 +1,14 @@
+import {BitStream} from 'bit-buffer';
+import {MessageHandler, MessageType, StopMessage, SyncTickMessage} from '../../Data/Message';
+
+export const StopHandler: MessageHandler<StopMessage> = {
+	parseMessage: (stream: BitStream) => {
+		return {
+			type: MessageType.Stop,
+			rawData: stream.readBitStream(0)
+		};
+	},
+	encodeMessage: (message, stream) => {
+		// noop
+	}
+};

src/Parser/Packet/GameEventList.ts

@@ -4,8 +4,6 @@ import {GameEvent, GameEventType} from '../../Data/GameEventTypes';
 import {GameEventListPacket} from '../../Data/Packet';
 
 export function ParseGameEventList(stream: BitStream): GameEventListPacket { // 30: gameEventList
-	const s = stream.index;
-
 	// list of game events and parameters
 	const numEvents = stream.readBits(9);
 	const length = stream.readBits(20);
@@ -28,6 +26,7 @@ export function ParseGameEventList(stream: BitStream): GameEventListPacket { //
 			entries
 		});
 	}
+
 	return {
 		packetType: 'gameEventList',
 		eventList

src/Parser/Packet/PacketEntities.ts

@@ -133,6 +133,7 @@ export function ParsePacketEntities(
 	const updatedEntries = stream.readBits(11);
 	const length = stream.readBits(20);
 	const updatedBaseLine = stream.readBoolean();
+	const start = stream.index;
 	const end = stream.index + length;
 	let entityId = -1;
 
@@ -166,6 +167,10 @@ export function ParsePacketEntities(
 				if (!sendTable) {
 					throw new Error(`Unknown sendTable ${packetEntity.serverClass.dataTable}`);
 				}
+				if (entityId === 55) {
+					console.log(`decode preserve: ${entityId} = ${sendTable.name}, ${receivedEntities.length}/${i} ${stream.index} ${end} tick ${state.tick}`);
+					console.log(receivedEntities[receivedEntities.length - 1], start, entityId, diff);
+				}
 				const updatedProps = getEntityUpdate(sendTable, stream);
 				packetEntity.applyPropUpdate(updatedProps);
 				receivedEntities.push(packetEntity);
@@ -173,7 +178,7 @@ export function ParsePacketEntities(
 				const packetEntity = getPacketEntityForExisting(entityId, state, pvs);
 				receivedEntities.push(packetEntity);
 			} else {
-				// throw new Error(`No existing entity to update with id ${entityId}`);
+				throw new Error(`No existing entity to update with id ${entityId}`);
 			}
 		}
 
@@ -233,6 +238,9 @@ export function EncodePacketEntities(packet: PacketEntitiesPacket, stream: BitSt
 			writeEnterPVS(entity, stream, state, packet.baseLine);
 		} else if (entity.pvs === PVS.PRESERVE) {
 			const sendTable = getSendTable(state, entity.serverClass.dataTable);
+			if (entity.entityIndex === 55) {
+				console.log(`encode preserve: ${entity.entityIndex} = ${entity.serverClass.dataTable}`);
+			}
 			encodeEntityUpdate(entity.props, sendTable, stream);
 		}
 	}

src/Parser/readBitVar.ts

@@ -52,7 +52,7 @@ export const readUBitVar = readBitVar;
 export function readVarInt(stream: BitStream, signed: boolean = false) {
 	let result = 0;
 	for (let i = 0; i < 35; i += 7) {
-		const byte = stream.readBits(8);
+		const byte = stream.readUint8();
 		result |= ((byte & 0x7F) << i);
 
 		if ((byte >> 7) === 0) {

src/Transformer.ts

@@ -0,0 +1,38 @@
+import {BitStream} from 'bit-buffer';
+import {Parser} from './Parser';
+import {Encoder} from './Encoder';
+import {Packet} from './Data/Packet';
+import {Message, MessageType} from './Data/Message';
+
+export type PacketTransform = (packet: Packet) => Packet;
+
+export type MessageTransform = (message: Message) => Message;
+
+export function nullTransform<T extends Packet | Message>(input: T): T {
+	return input;
+}
+
+export class Transformer extends Parser {
+	private readonly encoder: Encoder;
+
+	constructor(sourceStream: BitStream, targetStream: BitStream) {
+		super(sourceStream);
+		this.encoder = new Encoder(targetStream);
+	}
+
+	public transform(packetTransform: PacketTransform, messageTransform: MessageTransform) {
+		this.encoder.encodeHeader(this.getHeader());
+
+		for (const message of this.getMessages()) {
+			this.parserState.handleMessage(message);
+			if (message.type === MessageType.Packet) {
+				for (const packet of message.packets) {
+					this.parserState.handlePacket(packet);
+				}
+				message.packets = message.packets.map(packetTransform);
+			}
+
+			this.encoder.writeMessage(messageTransform(message));
+		}
+	}
+}

src/tests/data/short.json

@@ -0,0 +1,695 @@
+{
+  "chat": [
+    {
+      "kind": "TF_Chat_All",
+      "from": "-[MG]-  Linc",
+      "text": "hf",
+      "tick": 41683
+    },
+    {
+      "kind": "TF_Chat_All",
+      "from": "-[MG]-  Linc",
+      "text": "gg",
+      "tick": 74952
+    },
+    {
+      "kind": "TF_Chat_All",
+      "from": "sientalprime",
+      "text": "gr",
+      "tick": 75279
+    }
+  ],
+  "users": {
+    "2": {
+      "classes": {},
+      "name": "SourceTV",
+      "steamId": "BOT",
+      "userId": 2
+    },
+    "3": {
+      "classes": {
+        "3": 12
+      },
+      "name": "Oneflower",
+      "steamId": "[U:1:72084]",
+      "userId": 3,
+      "team": "blue"
+    },
+    "4": {
+      "classes": {
+        "4": 10,
+        "5": 2
+      },
+      "name": "THG | The Bearded MIG",
+      "steamId": "[U:1:79943218]",
+      "userId": 4,
+      "team": "blue"
+    },
+    "5": {
+      "classes": {
+        "4": 3,
+        "5": 7,
+        "6": 1
+      },
+      "name": "sientalprime",
+      "steamId": "[U:1:315192136]",
+      "userId": 5,
+      "team": "blue"
+    },
+    "6": {
+      "classes": {
+        "1": 11,
+        "2": 2,
+        "6": 1,
+        "7": 4
+      },
+      "name": "Colonel Miggy-Bears",
+      "steamId": "[U:1:4783268]",
+      "userId": 6,
+      "team": "blue"
+    },
+    "7": {
+      "classes": {
+        "1": 11,
+        "2": 1
+      },
+      "name": "-[MG]-  Linc",
+      "steamId": "[U:1:25900190]",
+      "userId": 7,
+      "team": "blue"
+    },
+    "8": {
+      "classes": {
+        "3": 11
+      },
+      "name": "J1ll ✧ stipuha zavisimyy",
+      "steamId": "[U:1:70354528]",
+      "userId": 8,
+      "team": "red"
+    },
+    "9": {
+      "classes": {
+        "3": 10
+      },
+      "name": "dzapis",
+      "steamId": "[U:1:134795814]",
+      "userId": 9,
+      "team": "red"
+    },
+    "10": {
+      "classes": {
+        "1": 1,
+        "3": 10,
+        "8": 2
+      },
+      "name": "SAVE_THE_SPYCRABS",
+      "steamId": "[U:1:125755589]",
+      "userId": 10,
+      "team": "blue"
+    },
+    "11": {
+      "classes": {
+        "1": 9
+      },
+      "name": "skq",
+      "steamId": "[U:1:113575586]",
+      "userId": 11,
+      "team": "red"
+    },
+    "12": {
+      "classes": {
+        "4": 7
+      },
+      "name": "Dunkelheit",
+      "steamId": "[U:1:52631210]",
+      "userId": 12,
+      "team": "red"
+    },
+    "13": {
+      "classes": {
+        "1": 7
+      },
+      "name": "Alexander",
+      "steamId": "[U:1:101341390]",
+      "userId": 13,
+      "team": "red"
+    },
+    "14": {
+      "classes": {
+        "5": 6
+      },
+      "name": "Dr.Oetker",
+      "steamId": "[U:1:76315857]",
+      "userId": 14,
+      "team": "red"
+    }
+  },
+  "deaths": [
+    {
+      "killer": 3,
+      "assister": null,
+      "victim": 11,
+      "weapon": "quake_rl",
+      "tick": 41352
+    },
+    {
+      "killer": 11,
+      "assister": null,
+      "victim": 6,
+      "weapon": "scattergun",
+      "tick": 43136
+    },
+    {
+      "killer": 9,
+      "assister": 12,
+      "victim": 7,
+      "weapon": "quake_rl",
+      "tick": 43190
+    },
+    {
+      "killer": 11,
+      "assister": 12,
+      "victim": 10,
+      "weapon": "scattergun",
+      "tick": 43515
+    },
+    {
+      "killer": 11,
+      "assister": null,
+      "victim": 3,
+      "weapon": "scattergun",
+      "tick": 43817
+    },
+    {
+      "killer": 8,
+      "assister": 14,
+      "victim": 4,
+      "weapon": "shotgun_soldier",
+      "tick": 44729
+    },
+    {
+      "killer": 12,
+      "assister": 14,
+      "victim": 7,
+      "weapon": "tf_projectile_pipe_remote",
+      "tick": 45866
+    },
+    {
+      "killer": 3,
+      "assister": 7,
+      "victim": 8,
+      "weapon": "world",
+      "tick": 45900
+    },
+    {
+      "killer": 12,
+      "assister": 14,
+      "victim": 3,
+      "weapon": "tf_projectile_pipe_remote",
+      "tick": 45954
+    },
+    {
+      "killer": 12,
+      "assister": 14,
+      "victim": 6,
+      "weapon": "tf_projectile_pipe_remote",
+      "tick": 46185
+    },
+    {
+      "killer": 4,
+      "assister": null,
+      "victim": 13,
+      "weapon": "tf_projectile_pipe",
+      "tick": 46445
+    },
+    {
+      "killer": 11,
+      "assister": 12,
+      "victim": 10,
+      "weapon": "scattergun",
+      "tick": 46456
+    },
+    {
+      "killer": 9,
+      "assister": null,
+      "victim": 4,
+      "weapon": "quake_rl",
+      "tick": 46491
+    },
+    {
+      "killer": 12,
+      "assister": null,
+      "victim": 5,
+      "weapon": "tf_projectile_pipe",
+      "tick": 46607
+    },
+    {
+      "killer": 11,
+      "assister": 9,
+      "victim": 7,
+      "weapon": "scattergun",
+      "tick": 48554
+    },
+    {
+      "killer": 8,
+      "assister": 13,
+      "victim": 4,
+      "weapon": "cow_mangler",
+      "tick": 48693
+    },
+    {
+      "killer": 11,
+      "assister": 12,
+      "victim": 6,
+      "weapon": "scattergun",
+      "tick": 48763
+    },
+    {
+      "killer": 9,
+      "assister": 8,
+      "victim": 3,
+      "weapon": "quake_rl",
+      "tick": 48835
+    },
+    {
+      "killer": 13,
+      "assister": 14,
+      "victim": 10,
+      "weapon": "scattergun",
+      "tick": 48959
+    },
+    {
+      "killer": 11,
+      "assister": null,
+      "victim": 5,
+      "weapon": "scattergun",
+      "tick": 49312
+    },
+    {
+      "killer": 8,
+      "assister": null,
+      "victim": 4,
+      "weapon": "shotgun_soldier",
+      "tick": 51581
+    },
+    {
+      "killer": 10,
+      "assister": 3,
+      "victim": 8,
+      "weapon": "tf_projectile_rocket",
+      "tick": 51658
+    },
+    {
+      "killer": 12,
+      "assister": null,
+      "victim": 3,
+      "weapon": "tf_projectile_pipe_remote",
+      "tick": 51866
+    },
+    {
+      "killer": 12,
+      "assister": null,
+      "victim": 7,
+      "weapon": "tf_projectile_pipe_remote",
+      "tick": 51907
+    },
+    {
+      "killer": 6,
+      "assister": null,
+      "victim": 11,
+      "weapon": "degreaser",
+      "tick": 52054
+    },
+    {
+      "killer": 12,
+      "assister": 13,
+      "victim": 6,
+      "weapon": "tf_projectile_pipe",
+      "tick": 52087
+    },
+    {
+      "killer": 10,
+      "assister": null,
+      "victim": 12,
+      "weapon": "tf_projectile_rocket",
+      "tick": 52117
+    },
+    {
+      "killer": 9,
+      "assister": null,
+      "victim": 10,
+      "weapon": "quake_rl",
+      "tick": 52431
+    },
+    {
+      "killer": 5,
+      "assister": null,
+      "victim": 9,
+      "weapon": "ubersaw",
+      "tick": 52628
+    },
+    {
+      "killer": 14,
+      "assister": 13,
+      "victim": 5,
+      "weapon": "ubersaw",
+      "tick": 52721
+    },
+    {
+      "killer": 9,
+      "assister": 11,
+      "victim": 4,
+      "weapon": "quake_rl",
+      "tick": 55162
+    },
+    {
+      "killer": 3,
+      "assister": 4,
+      "victim": 9,
+      "weapon": "quake_rl",
+      "tick": 55369
+    },
+    {
+      "killer": 13,
+      "assister": 11,
+      "victim": 7,
+      "weapon": "pistol_scout",
+      "tick": 55645
+    },
+    {
+      "killer": 12,
+      "assister": 14,
+      "victim": 3,
+      "weapon": "tf_projectile_pipe",
+      "tick": 56902
+    },
+    {
+      "killer": 10,
+      "assister": 5,
+      "victim": 8,
+      "weapon": "tf_projectile_rocket",
+      "tick": 57415
+    },
+    {
+      "killer": 12,
+      "assister": null,
+      "victim": 5,
+      "weapon": "tf_projectile_pipe_remote",
+      "tick": 57785
+    },
+    {
+      "killer": 12,
+      "assister": 14,
+      "victim": 10,
+      "weapon": "tf_projectile_pipe",
+      "tick": 57963
+    },
+    {
+      "killer": 7,
+      "assister": null,
+      "victim": 13,
+      "weapon": "force_a_nature",
+      "tick": 58048
+    },
+    {
+      "killer": 4,
+      "assister": 7,
+      "victim": 11,
+      "weapon": "tf_projectile_pipe_remote",
+      "tick": 58164
+    },
+    {
+      "killer": 9,
+      "assister": 12,
+      "victim": 6,
+      "weapon": "quake_rl",
+      "tick": 58395
+    },
+    {
+      "killer": 7,
+      "assister": 3,
+      "victim": 12,
+      "weapon": "force_a_nature",
+      "tick": 58756
+    },
+    {
+      "killer": 9,
+      "assister": 14,
+      "victim": 7,
+      "weapon": "quake_rl",
+      "tick": 58758
+    },
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+}

src/tests/snapshot/transcode.ts

@@ -0,0 +1,39 @@
+import * as assert from 'assert';
+import {BitStream} from 'bit-buffer';
+import {readFileSync} from 'fs';
+import {DynamicBitStream} from '../../DynamicBitStream';
+import {nullTransform, Transformer} from '../../Transformer';
+import {Parser} from '../../Parser';
+import {Analyser} from '../../Analyser';
+
+function testDemo(name: string) {
+	const target = JSON.parse(readFileSync(`${__dirname}/../data/${name}.json`, 'utf8'));
+	const decodeStream = new BitStream(
+		readFileSync(`${__dirname}/../data/${name}.dem`).buffer as ArrayBuffer
+	);
+	const encodeStream = new DynamicBitStream(32 * 1024 * 1024);
+
+	const transformer = new Transformer(decodeStream, encodeStream);
+	transformer.transform(nullTransform, nullTransform);
+
+	const encodedLength = encodeStream.index;
+	encodeStream.index = 0;
+
+	console.log('start reparse');
+
+	const reParser = new Parser(encodeStream);
+	const analyser = new Analyser(reParser);
+	const parsed = analyser.getBody().getState();
+
+	const reParsedLength = encodeStream.index;
+
+	assert.equal(reParsedLength, encodedLength, 'Unexpected number of bits used when parsing encoding stream');
+
+	assert.deepEqual(JSON.parse(JSON.stringify(parsed)), target);
+}
+
+suite('Transcode demo', () => {
+	test('Noop transcode', () => {
+		testDemo('short');
+	});
+});