jetriBetter

// ==UserScript==
// @name        jetriBetter
// @namespace   jetriBetter
// @match       https://hololive.jetri.co/*
// @run-at      document-start
// @grant       none
// @version     1.0
// @author      トワ…
// @description Uses the APIs from holodex for the holotools website
// ==/UserScript==

"use strict";

// Emits 2 event types on `document`, where the event's `detail` property holds the jetri-fied API response:
//   "jetri-live": /v1/live
//   "jetri-channels": /v1/channels (`total` and `count` properties are always 1)

const jetriLiveFromHolodex = (x) => ({
  id: x.id,
  yt_video_key: x.id,
  bb_video_id: null,
  title: x.title,
  thumbnail: null,
  status: x.status,
  live_schedule: x.start_scheduled,
  live_start: x.start_actual ?? null,
  live_end: null,
  live_viewers: x.live_viewers ?? null,
  channel: {
    id: x.channel.id,
    yt_channel_id: x.channel.id,
    bb_space_id: null,
    name: x.channel.name,
    photo: x.channel.photo,
    published_at: null, // unused
    twitter_link: null, // unused
    view_count: 0,
    subscriber_count: 0,
    video_count: 0,
  },
});

const jetriChannelFromHolodex = (x, i) => ({
  id: x.id,
  yt_channel_id: x.id,
  bb_space_id: null,
  name: x.name,
  description: "",
  photo: x.photo,
  published_at: i, // used only for sorting
  twitter_link: x.twitter,
  view_count: 0,
  subscriber_count: x.subscriber_count,
  video_count: x.video_count,
  video_original: x.video_count,
});

const handleLive = ({ target }) => {
  const streams = [];
  for (const stream of JSON.parse(target.responseText)) {
    const isYoutubeStream = stream.placeholderType !== "external-stream"
      && (stream.status === "live" || stream.status === "upcoming");
    if (isYoutubeStream) {
      streams.push(jetriLiveFromHolodex(stream));
    }
  }

  const result = streams.reduce((a, stream) => {
    a[stream.status].push(stream);
    return a;
  }, {
    live: [],
    upcoming: [],
    ended: [],
    cached: true,
  });
  Object.defineProperty(target, "responseText", {
    value: JSON.stringify(result),
    writable: true,
    enumerable: true,
    configrable: true,
  });

  return result;
};

const handleChannels = ({ target }) => {
  const channels = JSON.parse(target.responseText).map(jetriChannelFromHolodex);

  Object.defineProperty(target, "responseText", {
    value: JSON.stringify({
      count: 1,
      total: 1,
      channels,
    }),
    writable: true,
    enumerable: true,
    configrable: true,
  });

  return channels;
};

const makeLoadHandler = (wrapper, name) => (fn) => (event) => {
  if (event.target.readyState === 4) {
    const detail = wrapper(event);
    document.dispatchEvent(new CustomEvent(name, { detail }));
  }
  fn.call(event.target, event);
};

const onreadystatechangeDescriptor =
  Object.getOwnPropertyDescriptor(XMLHttpRequest.prototype, "onreadystatechange");

const hijackReadystatechange = (xhr, wrapper) => void Object
  .defineProperty(xhr, "onreadystatechange", {
    get() {
      return onreadystatechangeDescriptor.get.call(this);
    },
    set(fn) {
      onreadystatechangeDescriptor.set.call(this, wrapper(fn));
    },
    enumerable: true,
    configrable: true,
  });

const origOpen = XMLHttpRequest.prototype.open;
const holodexLiveApiUrl =
  "https://holodex.net/api/v2/live?type=placeholder%2Cstream&org=Hololive";
const holodexChannelsApiUrl =
  "https://holodex.net/api/v2/channels?limit=100&offset=0&type=vtuber&org=Hololive&sort=suborg&order=asc";

Object.defineProperty(XMLHttpRequest.prototype, "open", {
  value: function open(method, url) {
    if (method.toUpperCase() === "GET") {
      const _url = new URL(url, "https://api.holotools.app/");
      if (_url.pathname === "/v1/live") {
        hijackReadystatechange(this, makeLoadHandler(handleLive, "jetri-live"));

        return origOpen.call(this, "GET", holodexLiveApiUrl);
      } else if (_url.pathname === "/v1/channels") {
        hijackReadystatechange(this, makeLoadHandler(handleChannels, "jetri-channels"));

        return origOpen.call(this, "GET", holodexChannelsApiUrl);
      }
    }

    return origOpen.apply(this, arguments);
  },
  writable: true,
  configrable: true,
});