/**
* @file Encoding/decoding functions for lanes-loudness packet
*
* @author aKuad
*/
import { typeof_detail } from "../util/typeof_detail.js";
import { LaneLoudness } from "./LaneLoudness.js";
/**
* Packet type ID of lanes-loudness packet
*/
export const LANES_LOUDNESS_PACKET_TYPE_ID = 0x40;
/**
* Create lanes-loudness packet
*
* @param {Array<LaneLoudness>} lanes_loudness LaneLoudness array to encode
* @returns {Uint8Array} Encoded packet
*
* @throws {TypeError} If `lanes_loudness` is not `Array`
* @throws {TypeError} If `lanes_loudness` has non `LaneLoudness` elements
*/
export function packet_lanes_loudness_encode(lanes_loudness) {
// Arguments type checking
if(!(lanes_loudness instanceof Array)) {
throw new TypeError(`lanes_loudness must be Array, but got ${typeof_detail(lanes_loudness)}`);
}
if(lanes_loudness.filter(e => !(e instanceof LaneLoudness)).length !== 0) {
throw new TypeError("Non LaneLoudness elements detected");
}
const packet_body = lanes_loudness.flatMap(e => Array.from(e.to_bytes()));
return Uint8Array.of(LANES_LOUDNESS_PACKET_TYPE_ID, ...packet_body);
}
/**
* Unpack lanes-loudness packet
*
* Note: About raises, see reference of `is_lanes_loudness_packet`.
*
* @param {Uint8Array} raw_packet Encoded packet
* @returns {Array<LaneLoudness>} Decoded data - Lane ID, current loudness
*/
export function packet_lanes_loudness_decode(raw_packet) {
is_lanes_loudness_packet(raw_packet, true);
const lanes_loudness = [];
for(let i = 1; i < raw_packet.length; i += 2) {
lanes_loudness.push(LaneLoudness.from_bytes(raw_packet.slice(i, i + 2)));
}
return lanes_loudness;
}
/**
* Verify the packet is lanes_loudness packet
*
* @param {Uint8Array} raw_packet Packet to verify
* @param {boolean} throw_on_invalid Toggle behavior when packet is invalid, true: raise exception, false: return false
* @returns {boolean} It is an lanes_loudness: true, otherwise: false (if throw_on_invalid === true, error will be thrown)
*
* @throws {TypeError} If `raw_packet` is not `Uint8Array`
* @throws {RangeError} If `raw_packet` is an empty array
* @throws {RangeError} If `raw_packet` has not an lanes_loudness packet type ID
* @throws {RangeError} If `raw_packet` is invalid length as lanes_loudness
*/
export function is_lanes_loudness_packet(raw_packet, throw_on_invalid = false) {
try {
// Arguments type checking
if(!(raw_packet instanceof Uint8Array)) {
throw new TypeError(`raw_packet must be Uint8Array, but got ${typeof_detail(raw_packet)}`);
}
// Packet content availability checking
if(raw_packet.length === 0) {
throw new RangeError("Empty array passed");
}
// Packet type ID checking
if(raw_packet[0] !== LANES_LOUDNESS_PACKET_TYPE_ID) {
throw new RangeError(`It has not an lanes_loudness packet type ID - should be ${LANES_LOUDNESS_PACKET_TYPE_ID}, but got ${raw_packet[0]}`);
}
// Packet length checking
if(((raw_packet.length - 1) % 2) !== 0) {
throw new RangeError("Invalid length bytes as lanes_loudness packet, may be broken");
}
} catch(e) {
if(throw_on_invalid) {
throw e;
} else {
return false;
}
}
return true;
}
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