| import { ERROR_PACKET, PACKET_TYPES_REVERSE, } from "./commons.js"; |
| import { decode } from "./contrib/base64-arraybuffer.js"; |
| const withNativeArrayBuffer = typeof ArrayBuffer === "function"; |
| export const decodePacket = (encodedPacket, binaryType) => { |
| if (typeof encodedPacket !== "string") { |
| return { |
| type: "message", |
| data: mapBinary(encodedPacket, binaryType), |
| }; |
| } |
| const type = encodedPacket.charAt(0); |
| if (type === "b") { |
| return { |
| type: "message", |
| data: decodeBase64Packet(encodedPacket.substring(1), binaryType), |
| }; |
| } |
| const packetType = PACKET_TYPES_REVERSE[type]; |
| if (!packetType) { |
| return ERROR_PACKET; |
| } |
| return encodedPacket.length > 1 |
| ? { |
| type: PACKET_TYPES_REVERSE[type], |
| data: encodedPacket.substring(1), |
| } |
| : { |
| type: PACKET_TYPES_REVERSE[type], |
| }; |
| }; |
| const decodeBase64Packet = (data, binaryType) => { |
| if (withNativeArrayBuffer) { |
| const decoded = decode(data); |
| return mapBinary(decoded, binaryType); |
| } |
| else { |
| return { base64: true, data }; // fallback for old browsers |
| } |
| }; |
| const mapBinary = (data, binaryType) => { |
| switch (binaryType) { |
| case "blob": |
| if (data instanceof Blob) { |
| // from WebSocket + binaryType "blob" |
| return data; |
| } |
| else { |
| // from HTTP long-polling or WebTransport |
| return new Blob([data]); |
| } |
| case "arraybuffer": |
| default: |
| if (data instanceof ArrayBuffer) { |
| // from HTTP long-polling (base64) or WebSocket + binaryType "arraybuffer" |
| return data; |
| } |
| else { |
| // from WebTransport (Uint8Array) |
| return data.buffer; |
| } |
| } |
| }; |