aes70/src/OCP1/response.js

A controller library for the AES70 protocol.

import { PDU } from './pdu.js';
import { EncodedArguments } from './encoded_arguments.js';

/**
 * Response packet.
 */
export class Response extends PDU {
  constructor(handle, status_code, param_count, parameters) {
    super();
    this.handle = handle;
    this.status_code = status_code | 0;
    this.param_count = param_count | 0;
    this.parameters = parameters || null;
  }

  static get messageType() {
    return 3;
  }

  encoded_length() {
    return 10 + (this.param_count ? this.parameters.byteLength : 0);
  }

  decode_from(data, pos, data_len) {
    let len = data.getUint32(pos);
    pos += 4;
    this.handle = data.getUint32(pos);
    pos += 4;
    this.status_code = data.getUint8(pos);
    pos++;
    this.param_count = data.getUint8(pos);
    pos++;
    len -= 10;
    if (len < 0) throw new Error('Bad Response length.');
    if (len > 0) {
      if (!this.param_count)
        throw new Error(
          'Decoding response with parameterCount=0 but %o bytes of parameters',
          len
        );
      this.parameters = data.buffer.slice(
        data.byteOffset + pos,
        data.byteOffset + pos + len
      );
      pos += len;
    }
    return pos;
  }

  encode_to(dst, pos) {
    dst.setUint32(pos, this.encoded_length());
    pos += 4;
    dst.setUint32(pos, this.handle);
    pos += 4;
    dst.setUint8(pos, this.status_code);
    pos++;
    dst.setUint8(pos, this.param_count);
    pos++;
    if (this.param_count) {
      if (this.parameters instanceof EncodedArguments) {
        pos = this.parameters.encodeTo(dst, pos);
      } else {
        new Uint8Array(dst.buffer).set(
          new Uint8Array(this.parameters),
          dst.byteOffset + pos
        );
        pos += this.parameters.byteLength;
      }
    }
    return pos;
  }
}