openbrawl-client/ByteStream/ByteStream.js

class ByteStream {
  constructor(buffer = null) {
    this.buffer = buffer || Buffer.alloc(0)
    this.offset = 0
  }

  readUInt8() {
    if (this.offset >= this.buffer.length) {
      throw new Error("ByteStream: Cannot read beyond buffer length")
    }
    const value = this.buffer.readUInt8(this.offset)
    this.offset += 1
    return value
  }

  readUInt16() {
    if (this.offset + 2 > this.buffer.length) {
      throw new Error("ByteStream: Cannot read beyond buffer length")
    }
    const value = this.buffer.readUInt16BE(this.offset)
    this.offset += 2
    return value
  }

  readUInt24() {
    if (this.offset + 3 > this.buffer.length) {
      throw new Error("ByteStream: Cannot read beyond buffer length")
    }
    const value =
      (this.buffer.readUInt8(this.offset) << 16) |
      (this.buffer.readUInt8(this.offset + 1) << 8) |
      this.buffer.readUInt8(this.offset + 2)
    this.offset += 3
    return value
  }

  readUInt32() {
    if (this.offset + 4 > this.buffer.length) {
      throw new Error("ByteStream: Cannot read beyond buffer length")
    }
    const value = this.buffer.readUInt32BE(this.offset)
    this.offset += 4
    return value
  }

  readInt32() {
    if (this.offset + 4 > this.buffer.length) {
      throw new Error("ByteStream: Cannot read beyond buffer length")
    }
    const value = this.buffer.readInt32BE(this.offset)
    this.offset += 4
    return value
  }

  readString() {
    const length = this.readUInt32()
    if (length === 0) return ""

    if (this.offset + length > this.buffer.length) {
      throw new Error("ByteStream: Cannot read beyond buffer length")
    }

    const value = this.buffer.toString("utf8", this.offset, this.offset + length)
    this.offset += length
    return value
  }

  readBytes(length) {
    if (this.offset + length > this.buffer.length) {
      throw new Error("ByteStream: Cannot read beyond buffer length")
    }
    const value = this.buffer.slice(this.offset, this.offset + length)
    this.offset += length
    return value
  }

  writeUInt8(value) {
    const buf = Buffer.alloc(1)
    buf.writeUInt8(value, 0)
    this.buffer = Buffer.concat([this.buffer, buf])
    return this
  }

  writeUInt16(value) {
    const buf = Buffer.alloc(2)
    buf.writeUInt16BE(value, 0)
    this.buffer = Buffer.concat([this.buffer, buf])
    return this
  }

  writeUInt24(value) {
    const buf = Buffer.alloc(3)
    buf.writeUInt8((value >> 16) & 0xff, 0)
    buf.writeUInt8((value >> 8) & 0xff, 1)
    buf.writeUInt8(value & 0xff, 2)
    this.buffer = Buffer.concat([this.buffer, buf])
    return this
  }

  writeUInt32(value) {
    const buf = Buffer.alloc(4)
    buf.writeUInt32BE(value, 0)
    this.buffer = Buffer.concat([this.buffer, buf])
    return this
  }

  writeInt32(value) {
    const buf = Buffer.alloc(4)
    buf.writeInt32BE(value, 0)
    this.buffer = Buffer.concat([this.buffer, buf])
    return this
  }

  writeString(value) {
    this.writeUInt32(value.length)
    if (value.length > 0) {
      const buf = Buffer.from(value, "utf8")
      this.buffer = Buffer.concat([this.buffer, buf])
    }
    return this
  }

  writeBytes(bytes) {
    this.buffer = Buffer.concat([this.buffer, bytes])
    return this
  }

  // Utility methods
  getBuffer() {
    return this.buffer
  }

  getLength() {
    return this.buffer.length
  }

  getRemainingLength() {
    return this.buffer.length - this.offset
  }

  getOffset() {
    return this.offset
  }

  setOffset(offset) {
    if (offset < 0 || offset > this.buffer.length) {
      throw new Error("ByteStream: Invalid offset")
    }
    this.offset = offset
    return this
  }

  reset() {
    this.buffer = Buffer.alloc(0)
    this.offset = 0
    return this
  }

  clone() {
    const cloned = new ByteStream(Buffer.from(this.buffer))
    cloned.offset = this.offset
    return cloned
  }

  toHex() {
    return this.buffer.toString("hex")
  }

  static fromHex(hexString) {
    return new ByteStream(Buffer.from(hexString, "hex"))
  }
}

module.exports = ByteStream