openreplay/frontend/app/player/web/messages/MFileReader.ts

115 lines
3.3 KiB
TypeScript

import type { Message } from './message.gen';
import type { RawMessage } from './raw.gen';
import { MType } from './raw.gen';
import RawMessageReader from './RawMessageReader.gen';
import rewriteMessage from './rewriter/rewriteMessage'
import Logger from 'App/logger'
// TODO: composition instead of inheritance
// needSkipMessage() and next() methods here use buf and p protected properties,
export default class MFileReader extends RawMessageReader {
private pLastMessageID: number = 0
private currentTime: number
public error: boolean = false
private noIndexes: boolean = false
constructor(data: Uint8Array, private startTime?: number, private logger= console) {
super(data)
}
public checkForIndexes() {
// 0xff 0xff 0xff 0xff 0xff 0xff 0xff 0xff = no indexes + weird fail over (don't ask)
const skipIndexes = this.readCustomIndex(this.buf.slice(0, 8)) === 72057594037927940
|| this.readCustomIndex(this.buf.slice(0, 9)) === 72057594037927940
if (skipIndexes) {
if (!this.noIndexes) {
this.skip(8)
}
this.noIndexes = true
}
}
private needSkipMessage(): boolean {
if (this.p === 0) return false
for (let i = 7; i >= 0; i--) {
if (this.buf[ this.p + i ] !== this.buf[ this.pLastMessageID + i ]) {
return this.buf[ this.p + i ] < this.buf[ this.pLastMessageID + i ]
}
}
return false
}
private getLastMessageID(): number {
let id = 0
for (let i = 0; i< 8; i++) {
id += this.buf[ this.p + i ] * 2**(8*i)
}
return id
}
/**
* Reads the messages from byteArray, returns null if read ended
* will reset to last correct pointer if encountered bad read
* (i.e mobfile was split in two parts and it encountered partial message)
* then will proceed to read next message when next mobfile part will be added
* via super.append
* */
private readRawMessage(): RawMessage | null {
try {
if (!this.noIndexes) {
this.skip(8)
}
return super.readMessage()
} catch (e) {
this.logger.error("Read message error:", e)
this.error = true
return null
}
}
currentTab = 'back-compatability'
readNext(): Message & { tabId: string; _index?: number } | null {
if (this.error || !this.hasNextByte()) {
return null
}
while (!this.noIndexes && this.needSkipMessage()) {
const skippedMessage = this.readRawMessage()
if (!skippedMessage) {
return null
}
Logger.group("Openreplay: Skipping messages ", skippedMessage)
}
this.pLastMessageID = this.noIndexes ? 0 : this.p
const rMsg = this.readRawMessage()
if (!rMsg) {
return null
}
if (rMsg.tp === MType.TabData) {
this.currentTab = rMsg.tabId
return this.readNext()
}
if (rMsg.tp === MType.Timestamp) {
if (!this.startTime) {
this.startTime = rMsg.timestamp
}
this.currentTime = rMsg.timestamp - this.startTime
return {
tp: 9999,
tabId: '',
time: this.currentTime,
}
}
const index = this.noIndexes ? 0 : this.getLastMessageID()
const msg = Object.assign(rewriteMessage(rMsg), {
// @ts-ignore
time: this.currentTime ?? rMsg.timestamp - this.startTime!,
tabId: this.currentTab,
}, !this.noIndexes ? { _index: index } : {})
return msg
}
}