patchwork-mapconverter/src/wc3maptranslator/HexBuffer.ts

Executable wrapper for https://github.com/ChiefOfGxBxL/WC3MapTranslator

import ieee754 from 'ieee754'
import IntN from 'intn'

const intToHex = (intV: number, isShort: boolean): string[] => {
  // Creates a new 32-bit integer from the given number
  const intSize = isShort ? 16 : 32

  // eslint-disable-next-line @typescript-eslint/no-unsafe-call, @typescript-eslint/no-unsafe-assignment
  const intNSize = new IntN(intSize)
  // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment, @typescript-eslint/no-unsafe-member-access, @typescript-eslint/no-unsafe-call
  const byteNum = intNSize.fromInt(intV).bytes

  // Map decimal bytes to hex bytes
  // Bytes are already in correct little-endian form
  // eslint-disable-next-line @typescript-eslint/no-unsafe-return, @typescript-eslint/no-unsafe-member-access, @typescript-eslint/no-unsafe-call
  return byteNum.map((Byte: number) => {
    return '0x' + Byte.toString(16)
  })
}
const charToHex = (character: string): string => {
  return '0x' + character.charCodeAt(0).toString(16)
}

export class HexBuffer {
  private readonly _buffer: string[] = []

  public addString (str: string): void {
    this.addStringNoNewline(str)
    this.addNullTerminator()
  }

  // as opposed to addChar(s) it can handle any unicode char instead of blindly converting to ascii, thus loosing data.
  public addStringNoNewline (str: string): void {
    // Write each char to the buffer
    // "ascii" | "utf8" | "utf-8" | "utf16le" | "ucs2"
    // | "ucs-2" | "base64" | "latin1" | "binary" | "hex"
    const buf = Buffer.from(str, 'utf-8')

    for (let i = 0; i < buf.length; i++) {
      this._buffer.push('0x' + buf[i].toString(16))
    }
  }

  public addNewLine (): void {
    this._buffer.push('0x0d') // carriage return
    this._buffer.push('0x0a') // line feed
  }

  public addChar (char: string): void {
    this._buffer.push(charToHex(char))
  }

  public addChars (chars: string): void {
    chars.split('').forEach(char => {
      this.addChar(char)
    })
  }

  public addInt (int: number, isShort = false): void {
    this._buffer.push(...intToHex(int, isShort))
  }

  public addShort (short: number): void {
    this.addInt(short, true)
  }

  public addFloat (float: number): void {
    const buf = Buffer.alloc(4)

    // ieee754.write(buffer, value, buffer offset, little-endian, mantissa length, bytes);
    ieee754.write(buf, float, 0, true, 23, 4)

    buf.forEach((byte) => {
      this._buffer.push('0x' + byte.toString(16))
    })
  }

  public addByte (byte: number): void {
    this._buffer.push('0x' + byte.toString(16))
  }

  public addNullTerminator (): void {
    this._buffer.push('0x0')
  }

  public getBuffer (): Buffer {
    return Buffer.from(this._buffer as unknown as WithImplicitCoercion<string>, 'hex')
  }
}