import { EndOfStreamError } from 'peek-readable'; import { AbstractTokenizer } from './AbstractTokenizer.js'; export class BufferTokenizer extends AbstractTokenizer { /** * Construct BufferTokenizer * @param uint8Array - Uint8Array to tokenize * @param options Tokenizer options */ constructor(uint8Array, options) { super(options); this.uint8Array = uint8Array; this.fileInfo = { ...options?.fileInfo ?? {}, ...{ size: uint8Array.length } }; } /** * Read buffer from tokenizer * @param uint8Array - Uint8Array to tokenize * @param options - Read behaviour options * @returns {Promise} */ async readBuffer(uint8Array, options) { if (options?.position) { if (options.position < this.position) { throw new Error('`options.position` must be equal or greater than `tokenizer.position`'); } this.position = options.position; } const bytesRead = await this.peekBuffer(uint8Array, options); this.position += bytesRead; return bytesRead; } /** * Peek (read ahead) buffer from tokenizer * @param uint8Array * @param options - Read behaviour options * @returns {Promise} */ async peekBuffer(uint8Array, options) { const normOptions = this.normalizeOptions(uint8Array, options); const bytes2read = Math.min(this.uint8Array.length - normOptions.position, normOptions.length); if ((!normOptions.mayBeLess) && bytes2read < normOptions.length) { throw new EndOfStreamError(); } uint8Array.set(this.uint8Array.subarray(normOptions.position, normOptions.position + bytes2read), normOptions.offset); return bytes2read; } close() { return super.close(); } supportsRandomAccess() { return true; } setPosition(position) { this.position = position; } }