@dderevjanik/termux-api/src/scripts/termux-brightness.ts

This library allows you to interact with your Android device from Node.js using termux-api

import { exec } from "child_process";

export interface BrightnessOptions {
  /**
   * Set the screen brightness between 0 and 255 or auto
   * @default 240
   */
  value: number | "auto";
}

/**
 * Set the screen brightness
 */
export async function brightness(options: BrightnessOptions): Promise<void> {
  if (options.value !== "auto" && (options.value < 0 || options.value > 255)) {
    throw new Error("Brightness value should be between 0 and 255");
  }
  return new Promise<void>((resolve, reject) => {
    const command = `termux-brightness ${options.value}`;
    exec(command, (error, stdout, stderr) => {
      if (error) {
        return reject(`Error: ${error.message}`);
      }
      if (stderr) {
        return reject(`Error: ${stderr}`);
      }
      return resolve();
    });
  });
}