@energypatrikhu/keysender/src/utils/index.ts

Node.js keyboard and mouse inputs emulator, global hotkey register for Windows

import { Delay, RGB, WindowInfo } from "../types";
import { _WindowInfo } from "../addon";
import fs from "fs";
import { CancelableFunction, SetThisParameter } from "../types/utils";

const resolvedPromise = Promise.resolve();

export const random = (min: number, max: number) =>
  Math.floor(Math.random() * (max + 1 - min)) + min;

export const sleep = (delay: Delay) => {
  if (typeof delay != "number") {
    delay = random(delay[0], delay[1]);
  }

  return delay
    ? new Promise<void>((resolve) => {
        setTimeout(resolve, delay as number);
      })
    : resolvedPromise;
};

type StringsToBuffers<T extends any[]> = {
  [key in keyof T]: Extract<T[key], string> extends string
    ? Exclude<T[key], string> | Buffer
    : T[key];
};

export const stringsToBuffers = <T extends any[]>(args: T) =>
  args.map((item) =>
    typeof item === "string" ? Buffer.from(item, "ucs2") : item
  ) as StringsToBuffers<T>;

export const lazyGetters = <T extends {}, K extends keyof T>(
  self: T,
  modules: { [key in K]: () => T[key] }
) => {
  for (const key in modules) {
    Object.defineProperty(self, key, {
      configurable: true,
      get() {
        const value = modules[key]();

        Object.defineProperty(self, key, { value });

        return value;
      },
    });
  }
};

export const bindPick = <T extends {}, K extends keyof T>(
  worker: T,
  keys: K[]
) =>
  keys.reduce(
    (acc, key) => ({ ...acc, [key]: (worker[key] as Function).bind(worker) }),
    {} as { [key in K]: T[key] extends Function ? T[key] : never }
  );

export const noop = function () {};

const rgbToBgr = (color: number) =>
  ((color & 0xff) << 16) |
  (((color >> 8) & 0xff) << 8) |
  ((color >> 16) & 0xff);

export const toBGR = (color: number | string | RGB) => {
  switch (typeof color) {
    case "number":
      return rgbToBgr(color);

    case "string":
      return rgbToBgr(parseInt(color, 16));

    default:
      return (
        (color[0] & 0xff) | ((color[1] >> 8) & 0xff) | ((color[2] >> 16) & 0xff)
      );
  }
};

const getOffset = (data: DataView) => {
  for (let i = data.getUint16(4, false), pos = 12; i--; pos += 16) {
    if (
      String.fromCodePoint(
        data.getInt8(pos),
        data.getInt8(pos + 1),
        data.getInt8(pos + 2),
        data.getInt8(pos + 3)
      ) === "name"
    ) {
      return data.getUint32(pos + 8, false);
    }
  }
};

export const getFontName = (path: string) => {
  const data = new DataView(fs.readFileSync(path).buffer, 0);

  let offset = getOffset(data);

  if (offset !== undefined) {
    const keyPos = offset + data.getUint16(offset + 4);

    offset += 6;

    for (let i = data.getUint16(offset + 2); i--; ) {
      const t = data.getUint16(offset);

      offset += 6;

      if ((t === 0 || t === 3) && data.getUint16(offset) === 4) {
        const fontFullName = new Uint16Array(data.getUint16(offset + 2) / 2);

        for (
          let i = 0, charPos = keyPos + data.getUint16(offset + 4);
          i < fontFullName.length;
          i++, charPos += 2
        ) {
          fontFullName[i] = data.getUint16(charPos);
        }

        return Buffer.from(fontFullName);
      }

      offset += 6;
    }
  }

  throw new Error(`Something wrong with font '${path}'`);
};

export const normalizeWindowInfo = (windowInfo: _WindowInfo): WindowInfo => ({
  ...windowInfo,
  className: windowInfo.className.toString("ucs2"),
  title: windowInfo.title.toString("ucs2"),
});

type CancelRef = { isCanceled(): true | void; isCancelable?: true };

export const makeCancelable = <Fn extends (...args: any[]) => any>(
  fn: SetThisParameter<CancelRef, Fn>
) => {
  const cancelRef: CancelRef = { isCanceled: noop };

  const cancelableFn = fn.bind(cancelRef) as CancelableFunction<Fn>;

  let promise: Promise<void> | undefined;

  cancelableFn.cancelCurrent = () => {
    if (!promise && cancelRef.isCancelable) {
      promise = new Promise<void>((resolve) => {
        cancelRef.isCanceled = () => {
          cancelRef.isCanceled = noop;

          delete cancelRef.isCancelable;

          resolve();

          promise = undefined;

          return true;
        };
      });
    }

    return promise || resolvedPromise;
  };

  return cancelableFn;
};