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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
/// <reference path="../../core/internal.d.ts" />
"use strict";
((window) => {  const core = window.Deno.core;  const ops = core.ops;  const webidl = window.__bootstrap.webidl;  const { MessageEvent, defineEventHandler, setTarget } =    window.__bootstrap.event;  const { EventTarget } = window.__bootstrap.eventTarget;  const { DOMException } = window.__bootstrap.domException;  const {    ArrayPrototypeIndexOf,    ArrayPrototypeSplice,    ArrayPrototypePush,    Symbol,    Uint8Array,  } = window.__bootstrap.primordials;
  const _name = Symbol("[[name]]");  const _closed = Symbol("[[closed]]");
  const channels = [];  let rid = null;
  async function recv() {    while (channels.length > 0) {      const message = await core.opAsync("op_broadcast_recv", rid);
      if (message === null) {        break;      }
      const [name, data] = message;      dispatch(null, name, new Uint8Array(data));    }
    core.close(rid);    rid = null;  }
  function dispatch(source, name, data) {    for (const channel of channels) {      if (channel === source) continue; // Don't self-send.      if (channel[_name] !== name) continue;      if (channel[_closed]) continue;
      const go = () => {        if (channel[_closed]) return;        const event = new MessageEvent("message", {          data: core.deserialize(data), // TODO(bnoordhuis) Cache immutables.          origin: "http://127.0.0.1",        });        setTarget(event, channel);        channel.dispatchEvent(event);      };
      defer(go);    }  }
  // Defer to avoid starving the event loop. Not using queueMicrotask()  // for that reason: it lets promises make forward progress but can  // still starve other parts of the event loop.  function defer(go) {    setTimeout(go, 1);  }
  class BroadcastChannel extends EventTarget {    [_name];    [_closed] = false;
    get name() {      return this[_name];    }
    constructor(name) {      super();
      const prefix = "Failed to construct 'BroadcastChannel'";      webidl.requiredArguments(arguments.length, 1, { prefix });
      this[_name] = webidl.converters["DOMString"](name, {        prefix,        context: "Argument 1",      });
      this[webidl.brand] = webidl.brand;
      ArrayPrototypePush(channels, this);
      if (rid === null) {        // Create the rid immediately, otherwise there is a time window (and a        // race condition) where messages can get lost, because recv() is async.        rid = ops.op_broadcast_subscribe();        recv();      }    }
    postMessage(message) {      webidl.assertBranded(this, BroadcastChannelPrototype);
      const prefix = "Failed to execute 'postMessage' on 'BroadcastChannel'";      webidl.requiredArguments(arguments.length, 1, { prefix });
      if (this[_closed]) {        throw new DOMException("Already closed", "InvalidStateError");      }
      if (typeof message === "function" || typeof message === "symbol") {        throw new DOMException("Uncloneable value", "DataCloneError");      }
      const data = core.serialize(message);
      // Send to other listeners in this VM.      dispatch(this, this[_name], new Uint8Array(data));
      // Send to listeners in other VMs.      defer(() => core.opAsync("op_broadcast_send", rid, this[_name], data));    }
    close() {      webidl.assertBranded(this, BroadcastChannelPrototype);      this[_closed] = true;
      const index = ArrayPrototypeIndexOf(channels, this);      if (index === -1) return;
      ArrayPrototypeSplice(channels, index, 1);      if (channels.length === 0) {        ops.op_broadcast_unsubscribe(rid);      }    }  }
  defineEventHandler(BroadcastChannel.prototype, "message");  defineEventHandler(BroadcastChannel.prototype, "messageerror");  const BroadcastChannelPrototype = BroadcastChannel.prototype;
  window.__bootstrap.broadcastChannel = { BroadcastChannel };})(this);