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// Forked from https://github.com/stardazed/sd-streams/tree/8928cf04b035fd02fb1340b7eb541c76be37e546
// Copyright (c) 2018-Present by Arthur Langereis - @zenmumbler MIT
/* eslint-disable @typescript-eslint/no-explicit-any */
// TODO reenable this lint here
import { Queue, QueueImpl } from "./queue.ts";
import { isFiniteNonNegativeNumber } from "./shared-internals.ts";
export const queue_ = Symbol("queue_");
export const queueTotalSize_ = Symbol("queueTotalSize_");
export interface QueueElement<V> {
value: V;
size: number;
}
export interface QueueContainer<V> {
[queue_]: Queue<QueueElement<V>>;
[queueTotalSize_]: number;
}
export interface ByteQueueContainer {
[queue_]: Queue<{
buffer: ArrayBufferLike;
byteOffset: number;
byteLength: number;
}>;
[queueTotalSize_]: number;
}
export function dequeueValue<V>(container: QueueContainer<V>): V {
// Assert: container has[[queue]] and[[queueTotalSize]] internal slots.
// Assert: container.[[queue]] is not empty.
const pair = container[queue_].shift()!;
const newTotalSize = container[queueTotalSize_] - pair.size;
container[queueTotalSize_] = Math.max(0, newTotalSize); // < 0 can occur due to rounding errors.
return pair.value;
}
export function enqueueValueWithSize<V>(
container: QueueContainer<V>,
value: V,
size: number
): void {
// Assert: container has[[queue]] and[[queueTotalSize]] internal slots.
if (!isFiniteNonNegativeNumber(size)) {
throw new RangeError("Chunk size must be a non-negative, finite numbers");
}
container[queue_].push({ value, size });
container[queueTotalSize_] += size;
}
export function peekQueueValue<V>(container: QueueContainer<V>): V {
// Assert: container has[[queue]] and[[queueTotalSize]] internal slots.
// Assert: container.[[queue]] is not empty.
return container[queue_].front()!.value;
}
export function resetQueue<V>(
container: ByteQueueContainer | QueueContainer<V>
): void {
// Chrome (as of v67) has a steep performance cliff with large arrays
// and shift(), around about 50k elements. While this is an unusual case
// we use a simple wrapper around shift and push that is chunked to
// avoid this pitfall.
// @see: https://github.com/stardazed/sd-streams/issues/1
container[queue_] = new QueueImpl<any>();
// The code below can be used as a plain array implementation of the
// Queue interface.
// const q = [] as any;
// q.front = function() { return this[0]; };
// container[queue_] = q;
container[queueTotalSize_] = 0;
}
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