taichunmin / chameleon-ultra.js / 16902739519

import { Buffer } from '@taichunmin/buffer'

import JSZip from 'jszip'

import * as _ from 'lodash-es'

import { setObject } from '../iifeExportHelper'

export default class DfuZip {

  #appImage?: DfuImage | null

  #baseImage?: DfuImage | null

  #gitVersion?: string | null

  #manifest: DfuManifest | null = null

  #zip: JSZip | null = null

  readonly #buf: Buffer

  constructor (buf: Buffer) {

    this.#buf = buf

  }

  async getManifest (): Promise<DfuManifest> {

    this.#zip ??= await JSZip.loadAsync(this.#buf)

    this.#manifest ??= await (async () => {

      const manifestJson = await this.#zip?.file('manifest.json')?.async('string')

      if (_.isNil(manifestJson)) throw new Error('Unable to find manifest, is this a proper DFU package?')

      return JSON.parse(manifestJson).manifest

    })()

    return this.#manifest as DfuManifest

  }

  async getFirstImageFile (types: DfuImageType[]): Promise<DfuImage | null> {

    const manifest = await this.getManifest()

    for (const type of types) {

      const image = manifest[type]

      if (_.isNil(image)) continue

      const [header, body] = await Promise.all(_.map([image.dat_file, image.bin_file], async file => {

        const u8 = await this.#zip?.file(file)?.async('uint8array')

        if (_.isNil(u8)) throw new Error(`Failed to read ${file} from DFU package`)

        return Buffer.fromView(u8)

      }))

      return { type, header, body }

    }

    return null

  }

  async getBaseImage (): Promise<DfuImage | null> {

    if (this.#baseImage === undefined) this.#baseImage = await this.getFirstImageFile(['softdevice', 'bootloader', 'softdevice_bootloader'])

    return this.#baseImage

  }

  async getAppImage (): Promise<DfuImage | null> {

    if (this.#appImage === undefined) this.#appImage = await this.getFirstImageFile(['application'])

    return this.#appImage

  }

  async getGitVersion (): Promise<string | null> {

    if (this.#gitVersion === undefined) {

      const image = await this.getAppImage()

      this.#gitVersion = image?.body.toString('utf8').match(/\x00(v\d+(?:\.\d+)*[\w-]*)\x00/)?.[1] ?? null

    }

    return this.#gitVersion

  }

}

setObject(globalThis, ['ChameleonUltraJS', 'DfuZip'], DfuZip)