archived-g-helper/app/ScreenBrightness.cs

namespace GHelper
{
    using System;
    using System.Diagnostics;
    using System.Management;

    public static class ScreenBrightness
    {
        public static int Get()
        {
            using var mclass = new ManagementClass("WmiMonitorBrightness")
            {
                Scope = new ManagementScope(@"\\.\root\wmi")
            };
            using var instances = mclass.GetInstances();
            foreach (ManagementObject instance in instances)
            {
                return (byte)instance.GetPropertyValue("CurrentBrightness");
            }
            return 0;
        }

        public static void Set(int brightness)
        {
            using var mclass = new ManagementClass("WmiMonitorBrightnessMethods")
            {
                Scope = new ManagementScope(@"\\.\root\wmi")
            };
            using var instances = mclass.GetInstances();
            var args = new object[] { 1, brightness };
            foreach (ManagementObject instance in instances)
            {
                instance.InvokeMethod("WmiSetBrightness", args);
            }
        }

        public static int Adjust(int delta)
        {
            int brightness = Get();
            Debug.WriteLine(brightness);
            brightness = Math.Min(100, Math.Max(0, brightness + delta));
            Set(brightness);
            return brightness;
        }

    }
}